@article{CarlsohnScharhagRosenbergerHeydenreichetal.2013, author = {Carlsohn, Anja and Scharhag-Rosenberger, Friederike and Heydenreich, Juliane and Mayer, Frank}, title = {Vitamin-D-Status of athletes with higher UV-exposure during training}, series = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis}, volume = {60}, journal = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis}, number = {10}, publisher = {Umschau-Zeitschriftenverl.}, address = {Frankfurt, Main}, issn = {0174-0008}, pages = {174 -- 176}, year = {2013}, language = {de} } @article{MuellerBaurHirschmuelleretal.2006, author = {M{\"u}ller, Steffen and Baur, Heiner and Hirschmueller, Anja and Mayer, Frank}, title = {Validit{\"a}t des COP-Verlaufes zur Quantifizierung der funktionalen Gangentwicklung bei Kindern}, year = {2006}, abstract = {Functional gait development in children is discussed controversially. Differentiated information about the roll- over process of the foot, represented by the "Center of Pressure" (COP), are still missing. The purpose of the study was the validation of the COP-path to quantify the functional gait development of children. Plantar pressure distribution was measured barefoot with an individual speed on a walkway (tartan) - in 255 children aged between 2 and 15 years. The medial and lateral area enclosed between the COP-path and the bisection of plantar angle (A(med), A(lat), Sigma: A(ml)) was calculated from plantar pressure data. Furthermore, the duration of the COP-path in the heel (COPtimeF), midfoot (COPtimeM) and forefoot (COPtimeV) was analysed. The load distribution under the medial and lateral forefoot was also calculated. The variation coefficient (VC) was calculated as a measure of interindividual variability. The medio-lateral divergency of the COP (Aml) initially decreases with advancing age (-20.2\%), followed by a continuous increase (+27.2\%). No changes in VC (A(med), A(lat), and A(ml)) appeared during age-related development. COPtimeM remains constant in all children over time. In contrast to COPtimeM, Cop(time)F decreases from youngest to oldest children (-31.0\%), and COPtimeV increases (+41.7\%). After initial descent up to 8 years of age, VC (COPtimeF, COPtimeM, COPtimeV) remains constant. The mediolateral load under the forefoot did not change. The COP-Path is able to characterise the functional gait development of children. VC values indicate high individual variability of gait pattern. In this context, age-based standard values should be critically discussed}, language = {de} } @article{CarlsohnScharhagRosenbergerSchappetal.2012, author = {Carlsohn, Anja and Scharhag-Rosenberger, Friederike and Schapp, Lukas and Fusch, Gerhard and Mayer, Frank}, title = {Validity of the determination of energy input from a dietary record in persons of normal weight - dependence on the level of energy input comparison between elite sportsmen with very high energy intake and a control group of persons of normal weight}, series = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis}, volume = {59}, journal = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis}, number = {10}, publisher = {Umschau-Zeitschriftenverl.}, address = {Frankfurt, Main}, issn = {0174-0008}, doi = {10.4455/eu.2012.958}, pages = {572 -- 577}, year = {2012}, abstract = {Dietary records are often biased, especially those of overweight individuals. The purpose of the study was to investigate underreporting among persons of normal weight with a very high energy intake (El). The total energy expenditure (TEE) of 16 elite athletes (BMI 24 +/- 2 kg/m(2)) and 17 controls (BMI 23 3 kg/m2) was measured using the doubly-labeled water technique (DLW, 14d). El was estimated using 2 x 3-day dietary records. Underreporters were identified by BLACK'S cut-off (El:TEE < 0.76). 44\% of athletes (El: 3584 824 kcal/d; TEE: 4621 1460 kcal/d) and 29\% of controls (El: 2552 680 kcal/d; TEE: 3151 822 kcal/d) were identified as underreporters. TEE explains 52\% of underreporting. In summary, a high energy intake seems to strongly predict underreporting. Prevalence and magnitude of underreporting increase with increasing energy intake.}, language = {de} } @article{MuellerStollMuelleretal.2012, author = {M{\"u}ller, Steffen and Stoll, Josefine and M{\"u}ller, Juliane and Mayer, Frank}, title = {Validity of isokinetic trunk measurements with respect to healthy adults, athletes and low back pain patients}, series = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, volume = {20}, journal = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, number = {4}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0959-3020}, doi = {10.3233/IES-2012-00482}, pages = {255 -- 266}, year = {2012}, abstract = {Background: Isokinetic measurements are widely used to assess strength capacity in a clinical or research context. Nevertheless, the validity of isokinetic measures for identifying strength deficits and the evaluation of therapeutic process regarding different pathologies is yet to be established. Therefore, the purpose of this review is to evaluate the validity of isokinetic measures in a specific case: that of muscular capacity in low back pain (LBP). Methods: A literature search (PubMed; ISI Web of Knowledge; The Cochrane Library) covering the last 10 years was performed. Relevant papers regarding isokinetic trunk strength measures in healthy and patients with low back pain (PLBP) were searched. Peak torque values [Nm] and peak torque normalized to body weight [Nm/kg BW] were extracted for healthy and PLBP. Ranked mean values across studies were calculated for the concentric peak torque at 60 degrees/s as well as the flexion/extension (F/E) ratio. Results: 34 publications (31 flexion/extension; 3 rotation) were suitable for reporting detailed isokinetic strength measures in healthy or LBP (untrained adults, adolescents, athletes). Adolescents and athletes were different compared to normal adults in terms of absolute trunk strength values and the F/E ratio. Furthermore, isokinetic measures evaluating therapeutic process and isokinetic rehabilitation training were infrequent in literature (8 studies). Conclusion: Isokinetic measurements are valid for measuring trunk flexion/extension strength and F/E ratio in athletes, adolescents and (untrained) adults with/without LBP. The validity of trunk rotation is questionable due to a very small number of publications whereas no reliable source regarding lateral flexion could be traced. Therefore, isokinetic dynamometry may be utilized for identifying trunk strength deficits in healthy adults and PLBP.}, language = {en} } @inproceedings{EngelMuellerMuelleretal.2013, author = {Engel, Tilman and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Reschke, Antje and Kopinski, Stephan and Mayer, Frank}, title = {Validity and reliability of a new customised split-belt treadmill provoking unexpected walking perturbations}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {462 -- 462}, year = {2013}, language = {en} } @article{EngelMuellerKopinskietal.2017, author = {Engel, Tilman and Mueller, Juliane and Kopinski, Stephan and Reschke, Antje and Mueller, Steffen and Mayer, Frank}, title = {Unexpected walking perturbations: Reliability and validity of a new treadmill protocol to provoke muscular reflex activities at lower extremities and the trunk}, series = {Journal of biomechanics}, volume = {55}, journal = {Journal of biomechanics}, publisher = {Elsevier}, address = {Oxford}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2017.02.026}, pages = {152 -- 155}, year = {2017}, abstract = {Instrumented treadmills offer the potential to generate standardized walking perturbations, which are particularly rapid and powerful. However, technical requirements to release adequate perturbations regarding timing, duration and amplitude are demanding. This study investigated the test-retest reliability and validity of a new treadmill perturbation protocol releasing rapid and unexpected belt perturbations to provoke muscular reflex responses at lower extremities and the trunk. Fourteen healthy participants underwent two identical treadmill walking protocols, consisting of 10 superimposed one-sided belt perturbations (100 ms duration; 2 m/s amplitude), triggered by a plantar pressure insole 200 ms after heel contact. Delay, duration and amplitude of applied perturbations were recorded by 3D-motion capture. Muscular reflex responses (within 200 ms) were measured at lower extremities and the trunk (10-lead EMG). Data was analyzed descriptively (mean +/- SD). Reliability was analyzed using test-retest variability (TRV\%) and limits of agreement (LoA, bias +/- 1.96*SD). Perturbation delay was 202 14 ms, duration was 102 +/- 4 ms and amplitude was 2.1 +/- 0.01 m/s. TRV for perturbation delay, duration and amplitude ranged from 5.0\% to 5.7\%. LoA reached 3 +/- 36 ms for delay, 2 +/- 13 ms for duration and 0.0 +/- 0.3 m/s for amplitude. EMG amplitudes following perturbations ranged between 106 +/- 97\% and 909 +/- 979\% of unperturbed gait and EMG latencies between 82 +/- 14 ms and 106 +/- 16 ms. Minor differences between preset and observed perturbation characteristics and results of test-retest analysis prove a high validity with excellent reliability of the setup. Therefore, the protocol tested can be recommended to provoke muscular reflex responses at lower extremities and the trunk in perturbed walking. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{QuarmbyKhajooeiKurtzetal.2023, author = {Quarmby, Andrew James and Khajooei, Mina and Kurtz, Philip and Henschke, Jakob and Kim, MyoungHwee and Mayer, Frank and Engel, Tilman}, title = {Unexpected running perturbations}, series = {Frontiers in sports and active living}, volume = {5}, journal = {Frontiers in sports and active living}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {2624-9367}, doi = {10.3389/fspor.2023.1129058}, pages = {14}, year = {2023}, abstract = {Introduction Balance is vital for human health and experiments have been conducted to measure the mechanisms of postural control, for example studying reflex responses to simulated perturbations. Such studies are frequent in walking but less common in running, and an understanding of reflex responses to trip-like disturbances could enhance our understanding of human gait and improve approaches to training and rehabilitation. Therefore, the primary aim of this study was to investigate the technical validity and reliability of a treadmill running protocol with perturbations. A further exploratory aim was to evaluate the associated neuromuscular reflex responses to the perturbations, in the lower limbs. Methods Twelve healthy participants completed a running protocol (9 km/h) test-retest (2 weeks apart), whereby 30 unilateral perturbations were executed via the treadmill belts (presets:2.0 m/s amplitude;150 ms delay (post-heel contact);100ms duration). Validity of the perturbations was assessed via mean +/- SD comparison, percentage error calculation between the preset and recorded perturbation characteristics (PE\%), and coefficient of variation (CV\%). Test-retest reliability (TRV\%) and Bland-Altman analysis (BLA; bias +/- 1.96 * SD) was calculated for reliability. To measure reflex activity, electromyography (EMG) was applied in both legs. EMG amplitudes (root mean square normalized to unperturbed strides) and latencies [ms] were analysed descriptively. Results Left-side perturbation amplitude was 1.9 +/- 0.1 m/s, delay 105 +/- 2 ms, and duration 78 +/- 1 ms. Right-side perturbation amplitude was 1.9 +/- 0.1 m/s, delay 118 +/- 2 ms, duration 78 +/- 1 ms. PE\% ranged from 5-30\% for the recorded perturbations. CV\% of the perturbations ranged from 19.5-76.8\%. TRV\% for the perturbations was 6.4-16.6\%. BLA for the left was amplitude: 0.0 +/- 0.3m/s, delay: 0 +/- 17 ms, duration: 2 +/- 13 ms, and for the right was amplitude: 0.1 +/- 0.7, delay: 4 +/- 40 ms, duration: 1 +/- 35 ms. EMG amplitudes ranged from 175 +/- 141\%-454 +/- 359\% in both limbs. Latencies were 109 +/- 12-116 +/- 23 ms in the tibialis anterior, and 128 +/- 49-157 +/- 20 ms in the biceps femoris. Discussion Generally, this study indicated sufficient validity and reliability of the current setup considering the technical challenges and limitations, although the reliability of the right-sided perturbations could be questioned. The protocol provoked reflex responses in the lower extremities, especially in the leading leg. Acute neuromusculoskeletal adjustments to the perturbations could be studied and compared in clinical and healthy running populations, and the protocol could be utilised to monitor chronic adaptations to interventions over time.}, language = {en} } @inproceedings{IntziegianniCasselMuelleretal.2012, author = {Intziegianni, Konstantina and Cassel, Michael and M{\"u}ller, Steffen and Mayer, Frank}, title = {Ultrasound evaluation of the patellar tendon cross-sectional area and its relation to maximum force}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {714 -- 714}, year = {2012}, language = {en} } @article{KopinskiEngelCasseletal.2015, author = {Kopinski, Stephan and Engel, Tilman and Cassel, Michael and Fr{\"o}hlich, Katja and Mayer, Frank and Carlsohn, Anja}, title = {Ultrasound Applied to Subcutaneous Fat Tissue Measurements in International Elite Canoeists}, series = {International journal of sports medicine}, volume = {36}, journal = {International journal of sports medicine}, number = {14}, publisher = {Thieme}, address = {Stuttgart}, issn = {0172-4622}, doi = {10.1055/s-0035-1555857}, pages = {1134 -- 1141}, year = {2015}, abstract = {Subcutaneous adipose tissue (SAT) measurements with ultrasound have recently been introduced to assess body fat in elite athletes. However, appropriate protocols and data on various groups of athletes are missing. We investigated intra-rater reliability of SAT measurements using ultrasound in elite canoe athletes. 25 international level canoeists (18 male, 7 female; 23 +/- 4 years; 81 +/- 11 kg; 1.83 +/- 0.09 m; 20 +/- 3 training h/wk) were measured on 2 consecutive days. SAT was assessed with B-mode ultrasound at 8 sites (ISAK): triceps, subscapular, biceps, iliac crest, supraspinal, abdominal, front thigh, medial calf, and quantified using image analysis software. Data was analyzed descriptively (mean +/- SD, [range]). Coefficient of variation (CV \%), intraclass correlation coefficient (ICC, 2.1) and absolute (LoA) and ratio limits of agreement (RLoA) were calculated for day-to-day reliability. Mean sum of SAT thickness was 30.0 +/- 19.4 mm [8.0, 80.1 mm], with 3.9 +/- 1.8 mm [1.2 mm subscapular, 8.0 mm abdominal] for individual sites. CV for the sum of sites was 4.7 \%, ICC 0.99, LoA 1.7 +/- 3.6 mm, RLoA 0.940 (*/divided by 1.155). Measuring SAT with ultrasound has proved to have excellent day-to-day reliability in elite canoe athletes. Recommendations for standardization of the method will further increase accuracy and reproducibility.}, language = {en} } @article{IntziegianniCasselKoenigetal.2015, author = {Intziegianni, Konstantina and Cassel, Michael and K{\"o}nig, Niklas and M{\"u}ller, Steffen and Fr{\"o}hlich, Katja and Mayer, Frank}, title = {Ultrasonography for the assessment of the structural properties of the Achilles tendon in asymptomatic individuals: An intra-rater reproducibility study}, series = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, volume = {23}, journal = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, number = {4}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0959-3020}, doi = {10.3233/IES-150586}, pages = {263 -- 270}, year = {2015}, abstract = {BACKGROUND: Reproducible measurements of tendon structural properties are a prerequisite for accurate diagnosis of tendon disorders and for determination of their mechanical properties. Despite the widely used application of Ultrasonography (US) in musculoskeletal assessment, its operator dependency and lack of standardization influences the consistency of the measurement. OBJECTIVE: To evaluate the intra-rater reproducibility of a standardized US method assessing the structural properties of the Achilles tendon (AT). METHODS: Sixteen asymptomatic participants were positioned prone on an isokinetic dynamometer with the knee extended and ankle at 90. flexion. US was used to assess AT-length, cross-sectional area (CSA), and AT-elongation during isometric plantarflexion contraction. The intra-rater reproducibility was assessed by ICC (2.1), Test-Retest Variability (TRV, \%), Bland-Altman analyses (Bias +/- LoA [1.96*SD]), and Standard-Error of Measurement (SEM). RESULTS: Measurements of AT-length demonstrated an ICC of 0.93, TRV of 4.5 +/- 3.9\%, Bias +/- LoA of -2.8 +/- 25.0 mm and SEM of 6.6 mm. AT-CSA showed an ICC of 0.79, TRV of 8.7 +/- 9.6\%, Bias +/- LoA of 1.7 +/- 19.4 mm(2) and SEM of 5.3 mm(2). AT-elongation revealed an ICC of 0.92, TRV of 12.9 +/- 8.9\%, Bias +/- LoA of 0.3 +/- 5.7 mm and SEM of 1.5 mm. CONCLUSIONS: The presented methodology allows a reproducible assessment of Achilles tendon structural properties when performed by a single rater.}, language = {en} } @inproceedings{MuellerCasselMuelleretal.2014, author = {M{\"u}ller, Steffen and Cassel, Michael and M{\"u}ller, Juliane and Stoll, Josefine and Baur, Heiner and Mayer, Frank}, title = {Trunk strength in adolescent athletes with Spondylolisthesis with/without back pain during training: Pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {46}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {642 -- 642}, year = {2014}, language = {en} } @misc{MuellerStollCasseletal.2017, author = {M{\"u}ller, Steffen and Stoll, Josefine and Cassel, Michael and Mayer, Frank}, title = {Trunk Muscle Activity during Drop Jump Performance in Adolescent Athletes with Back Pain}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-395261}, pages = {9}, year = {2017}, abstract = {In the context of back pain, great emphasis has been placed on the importance of trunk stability, especially in situations requiring compensation of repetitive, intense loading induced during high-performance activities, e.g., jumping or landing. This study aims to evaluate trunk muscle activity during drop jump in adolescent athletes with back pain (BP) compared to athletes without back pain (NBP). Eleven adolescent athletes suffering back pain (BP: m/f: n = 4/7; 15.9 ± 1.3 y; 176 ± 11 cm; 68 ± 11 kg; 12.4 ± 10.5 h/we training) and 11 matched athletes without back pain (NBP: m/f: n = 4/7; 15.5 ± 1.3 y; 174 ± 7 cm; 67 ± 8 kg; 14.9 ± 9.5 h/we training) were evaluated. Subjects conducted 3 drop jumps onto a force plate (ground reaction force). Bilateral 12-lead SEMG (surface Electromyography) was applied to assess trunk muscle activity. Ground contact time [ms], maximum vertical jump force [N], jump time [ms] and the jump performance index [m/s] were calculated for drop jumps. SEMG amplitudes (RMS: root mean square [\%]) for all 12 single muscles were normalized to MIVC (maximum isometric voluntary contraction) and analyzed in 4 time windows (100 ms pre- and 200 ms post-initial ground contact, 100 ms pre- and 200 ms post-landing) as outcome variables. In addition, muscles were grouped and analyzed in ventral and dorsal muscles, as well as straight and transverse trunk muscles. Drop jump ground reaction force variables did not differ between NBP and BP (p > 0.05). Mm obliquus externus and internus abdominis presented higher SEMG amplitudes (1.3-1.9-fold) for BP (p < 0.05). Mm rectus abdominis, erector spinae thoracic/lumbar and latissimus dorsi did not differ (p > 0.05). The muscle group analysis over the whole jumping cycle showed statistically significantly higher SEMG amplitudes for BP in the ventral (p = 0.031) and transverse muscles (p = 0.020) compared to NBP. Higher activity of transverse, but not straight, trunk muscles might indicate a specific compensation strategy to support trunk stability in athletes with back pain during drop jumps. Therefore, exercises favoring the transverse trunk muscles could be recommended for back pain treatment.}, language = {en} } @article{MuellerStollMuelleretal.2017, author = {M{\"u}ller, Steffen and Stoll, Josefine and Mueller, Juliane and Cassel, Michael and Mayer, Frank}, title = {Trunk Muscle Activity during Drop Jump Performance in Adolescent Athletes with Back Pain}, series = {Frontiers in physiology}, volume = {8}, journal = {Frontiers in physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2017.00274}, pages = {124 -- 132}, year = {2017}, abstract = {In the context of back pain, great emphasis has been placed on the importance of trunk stability, especially in situations requiring compensation of repetitive, intense loading induced during high-performance activities, e.g., jumping or landing. This study aims to evaluate trunk muscle activity during drop jump in adolescent athletes with back pain (BP) compared to athletes without back pain (NBP). Eleven adolescent athletes suffering back pain (BP: m/f: n = 4/7; 15.9 +/- 1.3 y; 176 +/- 11 cm; 68 +/- 11 kg; 12.4 +/- 10.5 h/we training) and 11 matched athletes without back pain (NBP: m/f: n = 4/7; 15.5 +/- 1.3 y; 174 +/- 7 cm; 67 +/- 8 kg; 14.9 +/- 9.5 h/we training) were evaluated. Subjects conducted 3 drop jumps onto a force plate (ground reaction force). Bilateral 12-lead SEMG (surface Electromyography) was applied to assess trunk muscle activity. Ground contact time [ms], maximum vertical jump force [N], jump time [ms] and the jump performance index [m/s] were calculated for drop jumps. SEMG amplitudes (RMS: root mean square [\%]) for all 12 single muscles were normalized toMIVC (maximum isometric voluntary contraction) and analyzed in 4 time windows (100 ms pre- and 200 ms post-initial ground contact, 100 ms pre- and 200 ms post-landing) as outcome variables. In addition, muscles were grouped and analyzed in ventral and dorsal muscles, as well as straight and transverse trunk muscles. Drop jump ground reaction force variables did not differ between NBP and BP (p > 0.05). Mm obliquus externus and internus abdominis presented higher SEMG amplitudes (1.3-1.9-fold) for BP (p < 0.05). Mm rectus abdominis, erector spinae thoracic/lumbar and latissimus dorsi did not differ (p > 0.05). The muscle group analysis over the whole jumping cycle showed statistically significantly higher SEMG amplitudes for BP in the ventral (p = 0.031) and transverse muscles (p = 0.020) compared to NBP. Higher activity of transverse, but not straight, trunk muscles might indicate a specific compensation strategy to support trunk stability in athletes with back pain during drop jumps. Therefore, exercises favoring the transverse trunk muscles could be recommended for back pain treatment.}, language = {en} } @article{MuellerStollCasseletal.2017, author = {M{\"u}ller, Steffen and Stoll, Josefine and Cassel, Michael and Mayer, Frank}, title = {Trunk Muscle Activity during Drop Jump Performance in Adolescent Athletes with Back Pain}, series = {Frontiers in physiology}, volume = {8}, journal = {Frontiers in physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2017.00274}, year = {2017}, abstract = {In the context of back pain, great emphasis has been placed on the importance of trunk stability, especially in situations requiring compensation of repetitive, intense loading induced during high-performance activities, e.g., jumping or landing. This study aims to evaluate trunk muscle activity during drop jump in adolescent athletes with back pain (BP) compared to athletes without back pain (NBP). Eleven adolescent athletes suffering back pain (BP: m/f: n = 4/7; 15.9 ± 1.3 y; 176 ± 11 cm; 68 ± 11 kg; 12.4 ± 10.5 h/we training) and 11 matched athletes without back pain (NBP: m/f: n = 4/7; 15.5 ± 1.3 y; 174 ± 7 cm; 67 ± 8 kg; 14.9 ± 9.5 h/we training) were evaluated. Subjects conducted 3 drop jumps onto a force plate (ground reaction force). Bilateral 12-lead SEMG (surface Electromyography) was applied to assess trunk muscle activity. Ground contact time [ms], maximum vertical jump force [N], jump time [ms] and the jump performance index [m/s] were calculated for drop jumps. SEMG amplitudes (RMS: root mean square [\%]) for all 12 single muscles were normalized to MIVC (maximum isometric voluntary contraction) and analyzed in 4 time windows (100 ms pre- and 200 ms post-initial ground contact, 100 ms pre- and 200 ms post-landing) as outcome variables. In addition, muscles were grouped and analyzed in ventral and dorsal muscles, as well as straight and transverse trunk muscles. Drop jump ground reaction force variables did not differ between NBP and BP (p > 0.05). Mm obliquus externus and internus abdominis presented higher SEMG amplitudes (1.3-1.9-fold) for BP (p < 0.05). Mm rectus abdominis, erector spinae thoracic/lumbar and latissimus dorsi did not differ (p > 0.05). The muscle group analysis over the whole jumping cycle showed statistically significantly higher SEMG amplitudes for BP in the ventral (p = 0.031) and transverse muscles (p = 0.020) compared to NBP. Higher activity of transverse, but not straight, trunk muscles might indicate a specific compensation strategy to support trunk stability in athletes with back pain during drop jumps. Therefore, exercises favoring the transverse trunk muscles could be recommended for back pain treatment.}, language = {en} } @article{MuellerMuellerStolletal.2014, author = {M{\"u}ller, Juliane and M{\"u}ller, Steffen and Stoll, Josefine and Baur, Heiner and Mayer, Frank}, title = {Trunk extensor and flexor strength capacity in healthy young elite athletes aged 11-15 Years}, series = {Journal of strength and conditioning research : the research journal of the NSCA}, volume = {28}, journal = {Journal of strength and conditioning research : the research journal of the NSCA}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {1064-8011}, doi = {10.1519/JSC.0000000000000280}, pages = {1328 -- 1334}, year = {2014}, abstract = {Mueller, J, Mueller, S, Stoll, J, Baur, H, and Mayer, F. Trunk extensor and flexor strength capacity in healthy young elite athletes aged 11-15 years. J Strength Cond Res 28(5): 1328-1334, 2014-Differences in trunk strength capacity because of gender and sports are well documented in adults. In contrast, data concerning young athletes are sparse. The purpose of this study was to assess the maximum trunk strength of adolescent athletes and to investigate differences between genders and age groups. A total of 520 young athletes were recruited. Finally, 377 (n = 233/144 M/F; 13 +/- 1 years; 1.62 +/- 0.11 m height; 51 +/- 12 kg mass; training: 4.5 +/- 2.6 years; training sessions/week: 4.3 +/- 3.0; various sports) young athletes were included in the final data analysis. Furthermore, 5 age groups were differentiated (age groups: 11, 12, 13, 14, and 15 years; n = 90, 150, 42, 43, and 52, respectively). Maximum strength of trunk flexors (Flex) and extensors (Ext) was assessed in all subjects during isokinetic concentric measurements (60 degrees center dot s(-1); 5 repetitions; range of motion: 55 degrees). Maximum strength was characterized by absolute peak torque (Flex(abs), Ext(abs); N center dot m), peak torque normalized to body weight (Flex(norm), Ext(norm); N center dot m center dot kg(-1) BW), and Flex(abs)/Ext(abs) ratio (RKquot). Descriptive data analysis (mean +/- SD) was completed, followed by analysis of variance (alpha = 0.05; post hoc test [Tukey-Kramer]). Mean maximum strength for all athletes was 97 +/- 34 N center dot m in Flex(abs) and 140 +/- 50 N center dot m in Ext(abs) (Flex(norm) = 1.9 +/- 0.3 N center dot m center dot kg(-1) BW, Ext(norm) = 2.8 +/- 0.6 N center dot m center dot kg(-1) BW). Males showed statistically significant higher absolute and normalized values compared with females (p < 0.001). Flex(abs) and Ext(abs) rose with increasing age almost 2-fold for males and females (Flex(abs), Ext(abs): p < 0.001). Flex(norm) and Ext(norm) increased with age for males (p < 0.001), however, not for females (Flex(norm): p = 0.26; Ext(norm): p = 0.20). RKquot (mean +/- SD: 0.71 +/- 0.16) did not reveal any differences regarding age (p = 0.87) or gender (p = 0.43). In adolescent athletes, maximum trunk strength must be discussed in a gender- and age-specific context. The Flex(abs)/Ext(abs) ratio revealed extensor dominance, which seems to be independent of age and gender. The values assessed may serve as a basis to evaluate and discuss trunk strength in athletes.}, language = {en} } @article{MartinezValdesNegroLaineetal.2017, author = {Martinez-Valdes, Eduardo Andr{\´e}s and Negro, F. and Laine, C. M. and Falla, D. and Mayer, Frank and Farina, Dario}, title = {Tracking motor units longitudinally across experimental sessions with high-density surface electromyography}, series = {The Journal of Physiology}, volume = {595}, journal = {The Journal of Physiology}, publisher = {Wiley}, address = {Hoboken}, issn = {0022-3751}, doi = {10.1113/JP273662}, pages = {1479 -- 1496}, year = {2017}, abstract = {A new method is proposed for tracking individual motor units (MUs) across multiple experimental sessions on different days. The technique is based on a novel decomposition approach for high-density surface electromyography and was tested with two experimental studies for reliability and sensitivity. Experiment I (reliability): ten participants performed isometric knee extensions at 10, 30, 50 and 70\% of their maximum voluntary contraction (MVC) force in three sessions, each separated by 1 week. Experiment II (sensitivity): seven participants performed 2 weeks of endurance training (cycling) and were tested pre-post intervention during isometric knee extensions at 10 and 30\% MVC. The reliability (Experiment I) and sensitivity (Experiment II) of the measured MU properties were compared for the MUs tracked across sessions, with respect to all MUs identified in each session. In Experiment I, on average 38.3\% and 40.1\% of the identified MUs could be tracked across two sessions (1 and 2 weeks apart), for the vastus medialis and vastus lateralis, respectively. Moreover, the properties of the tracked MUs were more reliable across sessions than those of the full set of identified MUs (intra-class correlation coefficients ranged between 0.63-0.99 and 0.39-0.95, respectively). In Experiment II, similar to 40\% of the MUs could be tracked before and after the training intervention and training-induced changes in MU conduction velocity had an effect size of 2.1 (tracked MUs) and 1.5 (group of all identified motor units). These results show the possibility of monitoring MU properties longitudinally to document the effect of interventions or the progression of neuromuscular disorders.}, language = {en} } @inproceedings{KopinskiEngelMuelleretal.2013, author = {Kopinski, Stephan and Engel, Tilman and M{\"u}ller, Steffen and Mayer, Frank}, title = {Torque-EMG relationship of lower back muscles - a pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {7 -- 8}, year = {2013}, language = {en} } @inproceedings{ReschkeMuellerMuelleretal.2013, author = {Reschke, Antje and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Engel, Tilman and Mayer, Frank}, title = {Three-dimensional spine kinematics during perturbed treadmill walking - a pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {172 -- 172}, year = {2013}, language = {en} } @inproceedings{WangMayerDorenkampetal.2012, author = {Wang, Victor C. and Mayer, Frank and Dorenkamp, Marc and Bonaventura, Klaus}, title = {Three-dimensional global area tracking is a valuable quantitative parameter for left ventricular function in athletes}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {850 -- 850}, year = {2012}, language = {en} } @misc{BaurHirschmuellerJahnetal.2008, author = {Baur, Heiner and Hirschm{\"u}ller, Anja and Jahn, Michael and M{\"u}ller, Steffen and Mayer, Frank}, title = {Therapeutic efficiency and biomechanical effects of sport insoles in female runners}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {624}, issn = {1866-8364}, doi = {10.25932/publishup-43552}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-435525}, pages = {4}, year = {2008}, language = {en} } @misc{LinMayerWippert2022, author = {Lin, Chiao-I and Mayer, Frank and Wippert, Pia-Maria}, title = {The prevalence of chronic ankle instability in basketball athletes: a cross-sectional study}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Gesundheitswissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Gesundheitswissenschaftliche Reihe}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, doi = {10.25932/publishup-56589}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-565898}, pages = {1 -- 9}, year = {2022}, abstract = {Background Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence. Methods In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 ± 3.8 years, 23.3 ± 2.2 kg/m2) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test. Results In the surveyed cohort, 26\% had unilateral CAI while 50\% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05). Conclusions CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration.}, language = {en} } @article{LinMayerWippert2022, author = {Lin, Chiao-I and Mayer, Frank and Wippert, Pia-Maria}, title = {The prevalence of chronic ankle instability in basketball athletes: a cross-sectional study}, series = {BMC Sports Science, Medicine and Rehabilitation}, volume = {14}, journal = {BMC Sports Science, Medicine and Rehabilitation}, publisher = {BioMed Central Ltd}, address = {London}, issn = {2052-1847}, doi = {10.1186/s13102-022-00418-0}, pages = {1 -- 9}, year = {2022}, abstract = {Background Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence. Methods In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 ± 3.8 years, 23.3 ± 2.2 kg/m2) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test. Results In the surveyed cohort, 26\% had unilateral CAI while 50\% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05). Conclusions CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration.}, language = {en} } @article{LinMayerWippert2022, author = {Lin, Chiao-I and Mayer, Frank and Wippert, Pia-Maria}, title = {The prevalence of chronic ankle instability in basketball athletes}, series = {BMC sports science, medicine \& rehabilitation}, volume = {14}, journal = {BMC sports science, medicine \& rehabilitation}, number = {1}, publisher = {BMC}, address = {London}, issn = {2052-1847}, doi = {10.1186/s13102-022-00418-0}, pages = {9}, year = {2022}, abstract = {Background Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence. Methods In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 +/- 3.8 years, 23.3 +/- 2.2 kg/m(2)) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test. Results In the surveyed cohort, 26\% had unilateral CAI while 50\% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X-2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X-2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05). Conclusions CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration.}, language = {en} } @misc{MayerScharhagRosenbergerCarlsohnetal.2011, author = {Mayer, Frank and Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Cassel, Michael and M{\"u}ller, Steffen and Scharhag, J{\"u}rgen}, title = {The intensity and effects of strength training in the elderly}, series = {Deutsches {\"A}rzteblatt international : a weekly online journal of clinical medicine and public health}, volume = {108}, journal = {Deutsches {\"A}rzteblatt international : a weekly online journal of clinical medicine and public health}, number = {21}, publisher = {Dt. {\"A}rzte-Verl.}, address = {Cologne}, issn = {1866-0452}, doi = {10.3238/arztebl.2011.0359}, pages = {359 -- U30}, year = {2011}, abstract = {Background: The elderly need strength training more and more as they grow older to stay mobile for their everyday activities. The goal of training is to reduce the loss of muscle mass and the resulting loss of motor function. The dose-response relationship of training intensity to training effect has not yet been fully elucidated. Methods: PubMed was selectively searched for articles that appeared in the past 5 years about the effects and dose-response relationship of strength training in the elderly. Results: Strength training in the elderly (> 60 years) increases muscle strength by increasing muscle mass, and by improving the recruitment of motor units, and increasing their firing rate. Muscle mass can be increased through training at an intensity corresponding to 60\% to 85\% of the individual maximum voluntary strength. Improving the rate of force development requires training at a higher intensity (above 85\%), in the elderly just as in younger persons. It is now recommended that healthy old people should train 3 or 4 times weekly for the best results; persons with poor performance at the outset can achieve improvement even with less frequent training. Side effects are rare. Conclusion: Progressive strength training in the elderly is efficient, even with higher intensities, to reduce sarcopenia, and to retain motor function.}, language = {en} } @article{QuarmbyKhajooeiEngeletal.2019, author = {Quarmby, Andrew James and Khajooei, Mina and Engel, Tilman and Kaplick, Hannes and Mayer, Frank}, title = {The feasibility of a split-belt instrumented treadmill running protocol with perturbations}, series = {Journal of biomechanics}, volume = {98}, journal = {Journal of biomechanics}, publisher = {Elsevier}, address = {Oxford}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2019.109493}, pages = {5}, year = {2019}, abstract = {Unexpected perturbations during locomotion can occur during daily life or sports performance. Adequate compensation for such perturbations is crucial in maintaining effective postural control. Studies utilising instrumented treadmills have previously validated perturbed walking protocols, however responses to perturbed running protocols remain less investigated. Therefore, the purpose of this study was to investigate the feasibility of a new instrumented treadmill-perturbed running protocol.
Fifteen participants (age = 2 8 +/- 3 years; height = 172 +/- 9 cm; weight = 69 +/- 10 kg; 60\% female) completed an 8-minute running protocol at baseline velocity of 2.5 m/s (9 km/h), whilst 15 one-sided belt perturbations were applied (pre-set perturbation characteristics: 150 ms delay (post-heel contact); 2.0 m/s amplitude; 100 ms duration). Perturbation characteristics and EMG responses were recorded. Bland-Altman analysis (BLA) was employed (bias +/- limits of agreement (LOA; bias +/- 1.96*SD)) and intra-individual variability of repeated perturbations was assessed via Coefficients of Variation (CV) (mean +/- SD).
On average, 9.4 +/- 2.2 of 15 intended perturbations were successful. Perturbation delay was 143 +/- 10 ms, amplitude was 1.7 +/- 0.2 m/s and duration was 69 +/- 10 ms. BLA showed -7 +/- 13 ms for delay, -0.3 +/- 0.1 m/s for amplitude and -30 +/- 10 ms for duration. CV showed variability of 19 +/- 4.5\% for delay, 58 +/- 12\% for amplitude and 30 +/- 7\% for duration. EMG RMS amplitudes of the legs and trunk ranged from 113 +/- 25\% to 332 +/- 305\% when compared to unperturbed gait. This study showed that the application of sudden perturbations during running can be achieved, though with increased variability across individuals. The perturbations with the above characteristics appear to have elicited a neuromuscular response during running.}, language = {en} } @misc{LinHoutenbosLuetal.2021, author = {Lin, Chiao-I and Houtenbos, Sanne and Lu, Yu-Hsien and Mayer, Frank and Wippert, Pia-Maria}, title = {The epidemiology of chronic ankle instability with perceived ankle instability}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, issn = {1866-8364}, doi = {10.25932/publishup-53137}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-531375}, pages = {13}, year = {2021}, abstract = {Background: Chronic ankle instability, developing from ankle sprain, is one of the most common sports injuries. Besides it being an ankle issue, chronic ankle instability can also cause additional injuries. Investigating the epidemiology of chronic ankle instability is an essential step to develop an adequate injury prevention strategy. However, the epidemiology of chronic ankle instability remains unknown. Therefore, the purpose of this study was to investigate the epidemiology of chronic ankle instability through valid and reliable self-reported tools in active populations. Methods: An electronic search was performed on PubMed and Web of Science in July 2020. The inclusion criteria for articles were peer-reviewed, published between 2006 and 2020, using one of the valid and reliable tools to evaluate ankle instability, determining chronic ankle instability based on the criteria of the International Ankle Consortium, and including the outcome of epidemiology of chronic ankle instability. The risk of bias of the included studies was evaluated with an adapted tool for the sports injury review method. Results: After removing duplicated studies, 593 articles were screened for eligibility. Twenty full-texts were screened and finally nine studies were included, assessing 3804 participants in total. The participants were between 15 and 32 years old and represented soldiers, students, athletes and active individuals with a history of ankle sprain. The prevalence of chronic ankle instability was 25\%, ranging between 7 and 53\%. The prevalence of chronic ankle instability within participants with a history of ankle sprains was 46\%, ranging between 9 and 76\%. Five included studies identified chronic ankle instability based on the standard criteria, and four studies applied adapted exclusion criteria to conduct the study. Five out of nine included studies showed a low risk of bias. Conclusions: The prevalence of chronic ankle instability shows a wide range. This could be due to the different exclusion criteria, age, sports discipline, or other factors among the included studies. For future studies, standardized criteria to investigate the epidemiology of chronic ankle instability are required. The epidemiology of CAI should be prospective. Factors affecting the prevalence of chronic ankle instability should be investigated and clearly described.}, language = {en} } @article{LinHoutenbosLuetal.2021, author = {Lin, Chiao-I and Houtenbos, Sanne and Lu, Yu-Hsien and Mayer, Frank and Wippert, Pia-Maria}, title = {The epidemiology of chronic ankle instability with perceived ankle instability}, series = {Journal of foot and ankle research / Australasian Podiatry Council; Society of Chiropodists and Podiatrists (UK)}, volume = {14}, journal = {Journal of foot and ankle research / Australasian Podiatry Council; Society of Chiropodists and Podiatrists (UK)}, publisher = {BioMed Central}, address = {London}, issn = {1757-1146}, doi = {10.1186/s13047-021-00480-w}, pages = {11}, year = {2021}, abstract = {Background: Chronic ankle instability, developing from ankle sprain, is one of the most common sports injuries. Besides it being an ankle issue, chronic ankle instability can also cause additional injuries. Investigating the epidemiology of chronic ankle instability is an essential step to develop an adequate injury prevention strategy. However, the epidemiology of chronic ankle instability remains unknown. Therefore, the purpose of this study was to investigate the epidemiology of chronic ankle instability through valid and reliable self-reported tools in active populations. Methods: An electronic search was performed on PubMed and Web of Science in July 2020. The inclusion criteria for articles were peer-reviewed, published between 2006 and 2020, using one of the valid and reliable tools to evaluate ankle instability, determining chronic ankle instability based on the criteria of the International Ankle Consortium, and including the outcome of epidemiology of chronic ankle instability. The risk of bias of the included studies was evaluated with an adapted tool for the sports injury review method. Results: After removing duplicated studies, 593 articles were screened for eligibility. Twenty full-texts were screened and finally nine studies were included, assessing 3804 participants in total. The participants were between 15 and 32 years old and represented soldiers, students, athletes and active individuals with a history of ankle sprain. The prevalence of chronic ankle instability was 25\%, ranging between 7 and 53\%. The prevalence of chronic ankle instability within participants with a history of ankle sprains was 46\%, ranging between 9 and 76\%. Five included studies identified chronic ankle instability based on the standard criteria, and four studies applied adapted exclusion criteria to conduct the study. Five out of nine included studies showed a low risk of bias. Conclusions: The prevalence of chronic ankle instability shows a wide range. This could be due to the different exclusion criteria, age, sports discipline, or other factors among the included studies. For future studies, standardized criteria to investigate the epidemiology of chronic ankle instability are required. The epidemiology of CAI should be prospective. Factors affecting the prevalence of chronic ankle instability should be investigated and clearly described.}, language = {en} } @misc{DeWittHubertsNiedererWippertetal.2017, author = {De Witt Huberts, Jessie and Niederer, Daniel and Wippert, Pia-Maria and Mayer, Frank}, title = {The effects of a new practical and synergetic multimodal treatment for chronic back pain on pain-related cognitions and wellbeing}, series = {Psychosomatic medicine}, volume = {79}, journal = {Psychosomatic medicine}, number = {4}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0033-3174}, pages = {A22 -- A23}, year = {2017}, language = {en} } @misc{EichlerSalzwedelRabeetal.2019, author = {Eichler, Sarah and Salzwedel, Annett and Rabe, Sophie and Mueller, Steffen and Mayer, Frank and Wochatz, Monique and Hadzic, Miralem and John, Michael and Wegscheider, Karl and V{\"o}ller, Heinz}, title = {The Effectiveness of Telerehabilitation as a Supplement to Rehabilitation in Patients After Total Knee or Hip Replacement}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {589}, issn = {1866-8364}, doi = {10.25932/publishup-44096}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-440965}, pages = {14}, year = {2019}, abstract = {Background: Telerehabilitation can contribute to the maintenance of successful rehabilitation regardless of location and time. The aim of this study was to investigate a specific three-month interactive telerehabilitation routine regarding its effectiveness in assisting patients with physical functionality and with returning to work compared to typical aftercare. Objective: The aim of the study was to investigate a specific three-month interactive telerehabilitation with regard to effectiveness in functioning and return to work compared to usual aftercare. Methods: From August 2016 to December 2017, 111 patients (mean 54.9 years old; SD 6.8; 54.3\% female) with hip or knee replacement were enrolled in the randomized controlled trial. At discharge from inpatient rehabilitation and after three months, their distance in the 6-minute walk test was assessed as the primary endpoint. Other functional parameters, including health related quality of life, pain, and time to return to work, were secondary endpoints. Results: Patients in the intervention group performed telerehabilitation for an average of 55.0 minutes (SD 9.2) per week. Adherence was high, at over 75\%, until the 7th week of the three-month intervention phase. Almost all the patients and therapists used the communication options. Both the intervention group (average difference 88.3 m; SD 57.7; P=.95) and the control group (average difference 79.6 m; SD 48.7; P=.95) increased their distance in the 6-minute-walk-test. Improvements in other functional parameters, as well as in quality of life and pain, were achieved in both groups. The higher proportion of working patients in the intervention group (64.6\%; P=.01) versus the control group (46.2\%) is of note. Conclusions: The effect of the investigated telerehabilitation therapy in patients following knee or hip replacement was equivalent to the usual aftercare in terms of functional testing, quality of life, and pain. Since a significantly higher return-to-work rate could be achieved, this therapy might be a promising supplement to established aftercare.}, language = {en} } @article{EichlerSalzwedelRabeetal.2019, author = {Eichler, Sarah and Salzwedel, Annett and Rabe, Sophie and Mueller, Steffen and Mayer, Frank and Wochatz, Monique and Hadzic, Miralem and John, Michael and Wegscheider, Karl and V{\"o}ller, Heinz}, title = {The Effectiveness of Telerehabilitation as a Supplement to Rehabilitation in Patients After Total Knee or Hip Replacement}, series = {JMIR Rehabilitation and Assistive Technologies}, volume = {6}, journal = {JMIR Rehabilitation and Assistive Technologies}, number = {2}, publisher = {jmir rehab}, address = {Toronto}, issn = {2369-2529}, doi = {10.2196/14236}, pages = {12}, year = {2019}, abstract = {Background: Telerehabilitation can contribute to the maintenance of successful rehabilitation regardless of location and time. The aim of this study was to investigate a specific three-month interactive telerehabilitation routine regarding its effectiveness in assisting patients with physical functionality and with returning to work compared to typical aftercare. Objective: The aim of the study was to investigate a specific three-month interactive telerehabilitation with regard to effectiveness in functioning and return to work compared to usual aftercare. Methods: From August 2016 to December 2017, 111 patients (mean 54.9 years old; SD 6.8; 54.3\% female) with hip or knee replacement were enrolled in the randomized controlled trial. At discharge from inpatient rehabilitation and after three months, their distance in the 6-minute walk test was assessed as the primary endpoint. Other functional parameters, including health related quality of life, pain, and time to return to work, were secondary endpoints. Results: Patients in the intervention group performed telerehabilitation for an average of 55.0 minutes (SD 9.2) per week. Adherence was high, at over 75\%, until the 7th week of the three-month intervention phase. Almost all the patients and therapists used the communication options. Both the intervention group (average difference 88.3 m; SD 57.7; P=.95) and the control group (average difference 79.6 m; SD 48.7; P=.95) increased their distance in the 6-minute-walk-test. Improvements in other functional parameters, as well as in quality of life and pain, were achieved in both groups. The higher proportion of working patients in the intervention group (64.6\%; P=.01) versus the control group (46.2\%) is of note. Conclusions: The effect of the investigated telerehabilitation therapy in patients following knee or hip replacement was equivalent to the usual aftercare in terms of functional testing, quality of life, and pain. Since a significantly higher return-to-work rate could be achieved, this therapy might be a promising supplement to established aftercare.}, language = {en} } @inproceedings{ReschkeWolterSchoepflinetal.2012, author = {Reschke, Antje and Wolter, Martin and Sch{\"o}pflin, Marlene and K{\"o}nig, Niklas and Mayer, Frank and Baur, Heiner}, title = {The effect of foot orthoses on peroneal H-reflex in treadmill walking a pilot study}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {943 -- 943}, year = {2012}, language = {en} } @misc{LinKhajooeiEngeletal.2012, author = {Lin, Chiao-I and Khajooei, Mina and Engel, Tilman and Nair, Alexandra and Heikkila, Mika and Kaplick, Hannes and Mayer, Frank}, title = {The effect of chronic ankle instability on muscle activations in lower extremities}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, issn = {1866-8364}, doi = {10.25932/publishup-51563}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-515632}, pages = {17}, year = {2012}, abstract = {Background/Purpose Muscular reflex responses of the lower extremities to sudden gait disturbances are related to postural stability and injury risk. Chronic ankle instability (CAI) has shown to affect activities related to the distal leg muscles while walking. Its effects on proximal muscle activities of the leg, both for the injured- (IN) and uninjured-side (NON), remain unclear. Therefore, the aim was to compare the difference of the motor control strategy in ipsilateral and contralateral proximal joints while unperturbed walking and perturbed walking between individuals with CAI and matched controls. Materials and methods In a cross-sectional study, 13 participants with unilateral CAI and 13 controls (CON) walked on a split-belt treadmill with and without random left- and right-sided perturbations. EMG amplitudes of muscles at lower extremities were analyzed 200 ms after perturbations, 200 ms before, and 100 ms after (Post100) heel contact while walking. Onset latencies were analyzed at heel contacts and after perturbations. Statistical significance was set at alpha≤0.05 and 95\% confidence intervals were applied to determine group differences. Cohen's d effect sizes were calculated to evaluate the extent of differences. Results Participants with CAI showed increased EMG amplitudes for NON-rectus abdominus at Post100 and shorter latencies for IN-gluteus maximus after heel contact compared to CON (p<0.05). Overall, leg muscles (rectus femoris, biceps femoris, and gluteus medius) activated earlier and less bilaterally (d = 0.30-0.88) and trunk muscles (bilateral rectus abdominus and NON-erector spinae) activated earlier and more for the CAI group than CON group (d = 0.33-1.09). Conclusion Unilateral CAI alters the pattern of the motor control strategy around proximal joints bilaterally. Neuromuscular training for the muscles, which alters motor control strategy because of CAI, could be taken into consideration when planning rehabilitation for CAI.}, language = {en} } @article{LinKhajooeiEngeletal.2021, author = {Lin, Chiao-I and Khajooei, Mina and Engel, Tilman and Nair, Alexandra and Heikkila, Mika and Kaplick, Hannes and Mayer, Frank}, title = {The effect of chronic ankle instability on muscle activations in lower extremities}, series = {PLOS ONE / Public Library of Science}, volume = {16}, journal = {PLOS ONE / Public Library of Science}, number = {2}, publisher = {PLOS}, address = {San Francisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0247581}, pages = {15}, year = {2021}, abstract = {Background/Purpose Muscular reflex responses of the lower extremities to sudden gait disturbances are related to postural stability and injury risk. Chronic ankle instability (CAI) has shown to affect activities related to the distal leg muscles while walking. Its effects on proximal muscle activities of the leg, both for the injured- (IN) and uninjured-side (NON), remain unclear. Therefore, the aim was to compare the difference of the motor control strategy in ipsilateral and contralateral proximal joints while unperturbed walking and perturbed walking between individuals with CAI and matched controls. Materials and methods In a cross-sectional study, 13 participants with unilateral CAI and 13 controls (CON) walked on a split-belt treadmill with and without random left- and right-sided perturbations. EMG amplitudes of muscles at lower extremities were analyzed 200 ms after perturbations, 200 ms before, and 100 ms after (Post100) heel contact while walking. Onset latencies were analyzed at heel contacts and after perturbations. Statistical significance was set at alpha≤0.05 and 95\% confidence intervals were applied to determine group differences. Cohen's d effect sizes were calculated to evaluate the extent of differences. Results Participants with CAI showed increased EMG amplitudes for NON-rectus abdominus at Post100 and shorter latencies for IN-gluteus maximus after heel contact compared to CON (p<0.05). Overall, leg muscles (rectus femoris, biceps femoris, and gluteus medius) activated earlier and less bilaterally (d = 0.30-0.88) and trunk muscles (bilateral rectus abdominus and NON-erector spinae) activated earlier and more for the CAI group than CON group (d = 0.33-1.09). Conclusion Unilateral CAI alters the pattern of the motor control strategy around proximal joints bilaterally. Neuromuscular training for the muscles, which alters motor control strategy because of CAI, could be taken into consideration when planning rehabilitation for CAI.}, language = {en} } @article{SchomoellerSchugardtKotschetal.2021, author = {Schom{\"o}ller, Anne and Schugardt, Monique and Kotsch, Peggy and Mayer, Frank}, title = {The effect of body composition on cycling power during an incremental test in young athletes}, series = {Journal of strength and conditioning research : the research journal of the NSCA / National Strength \& Conditioning Association}, volume = {35}, journal = {Journal of strength and conditioning research : the research journal of the NSCA / National Strength \& Conditioning Association}, number = {11}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {1064-8011}, doi = {10.1519/JSC.0000000000003271}, pages = {3225 -- 3231}, year = {2021}, abstract = {Schomoller, A, Schugardt, M, Kotsch, P, and Mayer, F. The effect of body composition on cycling power during an incremental test in young athletes. J Strength Cond Res 35(11): 3225-3231, 2021-As body composition (BC) is a modifiable factor influencing sports performance, it is of interest for athletes and coaches to optimize BC to fulfill the specific physical demands of one sport discipline. The purpose of this study is to test the impact of body fat (BF) and fat-free mass (FFM) on aerobic performance in young athletes. Body composition parameters were evaluated among gender and age groups of young athletes undergoing their mandatory health examination. The maximal power (in Watts per kilogram body mass) of a stepwise incremental ergometer test was compared between 6 BC types: high BF, high FFM, high BF and high FFM, normal BC values, low BF, and low FFM. With increasing age (11-13 vs. 14-16 years) BF decreased and FFM increased in both genders. Both BC parameters, as well as body mass, correlated moderately with performance output (r = 0.36-0.6). Subjects with high BF or high FFM or both had significantly lower ergometer test results compared with those with low BF and FFM in all age and gender groups (p < 0.05). The finding that high levels of BF and FFM are detrimental for cycle power output is important to consider in disciplines that demand high levels of aerobic and anaerobic performance.}, language = {en} } @article{HenschkeStollKopinskietal.2020, author = {Henschke, Jakob and Stoll, Josefine and Kopinski, Stephan and Lu, Yu-Hsien and Mayer, Frank}, title = {The effect of a low volume trunk-stabilisation exercise protocol on biomechanical function and compliance}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {52}, journal = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {17}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, doi = {10.1249/01.mss.0000678760.27551.f6}, pages = {446 -- 447}, year = {2020}, language = {en} } @inproceedings{WeberMuellerOttoetal.2012, author = {Weber, Josefine and M{\"u}ller, Juliane and Otto, Christoph and Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Mayer, Frank}, title = {Test-retest-reliability of metabolic and cardiovascular load during isokinetic strength testing}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {375 -- 376}, year = {2012}, language = {en} } @article{CasselCarlsohnFroehlichetal.2016, author = {Cassel, Michael and Carlsohn, Anja and Fr{\"o}hlich, Katja and John, Mareike and Riegels, N. and Mayer, Frank}, title = {Tendon Adaptation to Sport-specific Loading in Adolescent Athletes}, series = {International journal of sports medicine}, volume = {37}, journal = {International journal of sports medicine}, publisher = {Thieme}, address = {Stuttgart}, issn = {0172-4622}, doi = {10.1055/s-0035-1559772}, pages = {159 -- 164}, year = {2016}, abstract = {Tendon adaptation due to mechanical loading is controversially discussed. However, data concerning the development of tendon thickness in adolescent athletes is sparse. The purpose of this study was to examine possible differences in Achilles (AT) and patellar tendon (PT) thickness in adolescent athletes while considering age, gender and sport-specific loading. In 500 adolescent competitive athletes of 16 different sports and 40 recreational controls both ATs and PTs were sonographically measured. Subjects were divided into 2 age groups (< 13; \&\#8805; 13 years) and 6 sport type categories (ball, combat, and water sports, combined disciplines, cycling, controls). In addition, 3 risk groups (low, moderate, high) were created according to the athlete's risk of developing tendinopathy. AT and PT thickness did not significantly differ between age groups (AT/PT:<13: 5.4±0.7 mm/3.6±0.5 mm;\&\#8805;13: 5.3±0.7 mm/3.6±0.5 mm). In both age groups males presented higher tendon thickness than females (p<0.001). AT thickness was highest in ball sports/cyclists and lowest in controls (p\&\#8804;0.002). PT thickness was greatest in water sports and lowest in controls (p=0.02). High risk athletes presented slightly higher AT thickness compared to the low risk group (p=0.03). Increased AT and PT thickness in certain sport types compared to controls supports the hypothesis of structural tendon adaptation due to sport-specific loading.}, language = {en} } @article{CasselStollMayer2015, author = {Cassel, Michael and Stoll, Josefine and Mayer, Frank}, title = {Tendinopathies of the Lower Extremities in Sport - Diagnostics and Therapy}, series = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation}, volume = {29}, journal = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation}, number = {2}, publisher = {Thieme}, address = {Stuttgart}, issn = {0932-0555}, doi = {10.1055/s-0034-1399668}, pages = {87 -- 98}, year = {2015}, abstract = {Tendinopathies are frequently the cause of chronic, load-dependent complaints of the lower extremity. Commonly, the large tendons of the ankle and knee joints are affected, especially the Achilles and patellar tendons. Repeated overuse in sports and/or daily activities is assumed as the aetiology. Besides the clinical examination including a comprehensive anamnesis of pain and training/loading, sonographic imaging has a high training/loading relevance for the diagnosis of tendon pathologies of the lower extremity. Training concepts are considered in first line as the treatment of choice. A combination with physical therapy interventions can be useful. In cases of a more severe pathology and long-standing complaints multimodal therapeutic options should be employed. The use of surgical treatment procedures should only be taken into account in case of failed response to conservative treatment.}, language = {de} } @article{MuellerMuellerEngeletal.2016, author = {M{\"u}ller, Juliane and M{\"u}ller, Steffen and Engel, Tilman and Reschke, Antje and Baur, Heiner and Mayer, Frank}, title = {Stumbling reactions during perturbed walking: Neuromuscular reflex activity and 3-D kinematics of the trunk - A pilot study}, series = {Journal of biomechanics}, volume = {49}, journal = {Journal of biomechanics}, publisher = {Elsevier}, address = {Oxford}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2015.09.041}, pages = {933 -- 938}, year = {2016}, abstract = {Stumbling led to an increase in ROM, compared to unperturbed gait, in all segments and planes. These increases ranged between 107 +/- 26\% (UTA/rotation) and 262 +/- 132\% (UTS/lateral flexion), significant only in lateral flexion. EMG activity of the trunk was increased during stumbling (abdominal: 665 +/- 283\%; back: 501 +/- 215\%), without significant differences between muscles. Provoked stumbling leads to a measurable effect on the trunk, quantifiable by an increase in ROM and EMG activity, compared to normal walking. Greater abdominal muscle activity and ROM of lateral flexion may indicate a specific compensation pattern occurring during stumbling. (C) 2015 Elsevier Ltd. All rights reserved.}, language = {en} } @misc{PuschmannDriessleinBecketal.2020, author = {Puschmann, Anne-Katrin and Drießlein, David and Beck, Heidrun and Arampatzis, Adamantios and Moreno Catal{\´a}, Maria and Schiltenwolf, Marcus and Mayer, Frank and Wippert, Pia-Maria}, title = {Stress and Self-Efficacy as Long-Term Predictors for Chronic Low Back Pain}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, issn = {1866-8364}, doi = {10.25932/publishup-46013}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-460134}, pages = {613 -- 621}, year = {2020}, abstract = {Purpose: Psychosocial variables are known risk factors for the development and chronification of low back pain (LBP). Psychosocial stress is one of these risk factors. Therefore, this study aims to identify the most important types of stress predicting LBP. Self-efficacy was included as a potential protective factor related to both, stress and pain. Participants and Methods: This prospective observational study assessed n = 1071 subjects with low back pain over 2 years. Psychosocial stress was evaluated in a broad manner using instruments assessing perceived stress, stress experiences in work and social contexts, vital exhaustion and life-event stress. Further, self-efficacy and pain (characteristic pain intensity and disability) were assessed. Using least absolute shrinkage selection operator regression, important predictors of characteristic pain intensity and pain-related disability at 1-year and 2-years follow-up were analyzed. Results: The final sample for the statistic procedure consisted of 588 subjects (age: 39.2 (± 13.4) years; baseline pain intensity: 27.8 (± 18.4); disability: 14.3 (± 17.9)). In the 1-year follow-up, the stress types "tendency to worry", "social isolation", "work discontent" as well as vital exhaustion and negative life events were identified as risk factors for both pain intensity and pain-related disability. Within the 2-years follow-up, Lasso models identified the stress types "tendency to worry", "social isolation", "social conflicts", and "perceived long-term stress" as potential risk factors for both pain intensity and disability. Furthermore, "self-efficacy" ("internality", "self-concept") and "social externality" play a role in reducing pain-related disability. Conclusion: Stress experiences in social and work-related contexts were identified as important risk factors for LBP 1 or 2 years in the future, even in subjects with low initial pain levels. Self-efficacy turned out to be a protective factor for pain development, especially in the long-term follow-up. Results suggest a differentiation of stress types in addressing psychosocial factors in research, prevention and therapy approaches.}, language = {en} } @article{PuschmannDriessleinBecketal.2020, author = {Puschmann, Anne-Katrin and Drießlein, David and Beck, Heidrun and Arampatzis, Adamantios and Moreno Catal{\´a}, Maria and Schiltenwolf, Marcus and Mayer, Frank and Wippert, Pia-Maria}, title = {Stress and Self-Efficacy as Long-Term Predictors for Chronic Low Back Pain}, series = {Journal of Pain Research}, volume = {13}, journal = {Journal of Pain Research}, publisher = {Dove Medical Press}, address = {Albany, Auckland}, issn = {1178-7090}, doi = {10.2147/JPR.S223893}, pages = {613 -- 621}, year = {2020}, abstract = {Purpose: Psychosocial variables are known risk factors for the development and chronification of low back pain (LBP). Psychosocial stress is one of these risk factors. Therefore, this study aims to identify the most important types of stress predicting LBP. Self-efficacy was included as a potential protective factor related to both, stress and pain. Participants and Methods: This prospective observational study assessed n = 1071 subjects with low back pain over 2 years. Psychosocial stress was evaluated in a broad manner using instruments assessing perceived stress, stress experiences in work and social contexts, vital exhaustion and life-event stress. Further, self-efficacy and pain (characteristic pain intensity and disability) were assessed. Using least absolute shrinkage selection operator regression, important predictors of characteristic pain intensity and pain-related disability at 1-year and 2-years follow-up were analyzed. Results: The final sample for the statistic procedure consisted of 588 subjects (age: 39.2 (± 13.4) years; baseline pain intensity: 27.8 (± 18.4); disability: 14.3 (± 17.9)). In the 1-year follow-up, the stress types "tendency to worry", "social isolation", "work discontent" as well as vital exhaustion and negative life events were identified as risk factors for both pain intensity and pain-related disability. Within the 2-years follow-up, Lasso models identified the stress types "tendency to worry", "social isolation", "social conflicts", and "perceived long-term stress" as potential risk factors for both pain intensity and disability. Furthermore, "self-efficacy" ("internality", "self-concept") and "social externality" play a role in reducing pain-related disability. Conclusion: Stress experiences in social and work-related contexts were identified as important risk factors for LBP 1 or 2 years in the future, even in subjects with low initial pain levels. Self-efficacy turned out to be a protective factor for pain development, especially in the long-term follow-up. Results suggest a differentiation of stress types in addressing psychosocial factors in research, prevention and therapy approaches.}, language = {en} } @article{MuellerCarlsohnMuelleretal.2012, author = {M{\"u}ller, Steffen and Carlsohn, Anja and M{\"u}ller, Juliane and Baur, Heiner and Mayer, Frank}, title = {Static and dynamic foot characteristics in children aged 1-13 years a cross-sectional study}, series = {Gait \& posture}, volume = {35}, journal = {Gait \& posture}, number = {3}, publisher = {Elsevier}, address = {Clare}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2011.10.357}, pages = {389 -- 394}, year = {2012}, abstract = {The aim of this study was to acquire static and dynamic foot geometry and loading in childhood, and to establish data for age groups of a population of 1-13 year old infants and children. A total of 10,382 children were recruited and 7788 children (48\% males and 52\% females) were finally included into the data analysis. For static foot geometry foot length and foot width were quantified in a standing position. Dynamic foot geometry and loading were assessed during walking on a walkway with self selected speed (Novel Emed X, 100 Hz, 4 sensors/cm(2)). Contact area (CA), peak pressure (PP), force time integral (FTI) and the arch index were calculated for the total, fore-, mid- and hindfoot. Results show that most static and dynamic foot characteristics change continuously during growth and maturation. Static foot length and width increased with age from 13.1 +/- 0.8 cm (length) and 5.7 +/- 0.4 cm (width) in the youngest to 24.4 +/- 1.5 cm (length) and 8.9 +/- 0.6 cm (width) in the oldest. A mean walking velocity of 0.94 +/- 0.25 m/s was observed. Arch-index ranged from 0.32 +/- 0.04 [a.u.] in the one-year old to 0.21 +/- 0.13 [a.u.] in the 5-year olds and remains constant afterwards. This study provides data for static and dynamic foot characteristics in children based on a cohort of 7788 subjects. Static and dynamic foot measures change differently during growth and maturation. Dynamic foot measurements provide additional information about the children's foot compared to static measures.}, language = {en} } @misc{AppiahDwomohMuellerHadzicetal.2017, author = {Appiah-Dwomoh, Edem Korkor and M{\"u}ller, Steffen and Hadzic, Miralem and Mayer, Frank}, title = {Star Excursion Balance Test in young athletes with back pain}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-400441}, pages = {11}, year = {2017}, abstract = {The Star Excursion Balance Test (SEBT) is effective in measuring dynamic postural control (DPC). This research aimed to determine whether DPC measured by the SEBT in young athletes (YA) with back pain (BP) is different from those without BP (NBP). 53 BP YA and 53 NBP YA matched for age, height, weight, training years, training sessions/week and training minutes/session were studied. Participants performed 4 practice trials after which 3 measurements in the anterior, posteromedial and posterolateral SEBT reach directions were recorded. Normalized reach distance was analyzed using the mean of all 3 measurements. There was no statistical significant difference (p > 0.05) between the reach distance of BP (87.2 ± 5.3, 82.4 ± 8.2, 78.7 ± 8.1) and NBP (87.8 ± 5.6, 82.4 ± 8.0, 80.0 ± 8.8) in the anterior, posteromedial and posterolateral directions respectively. DPC in YA with BP, as assessed by the SEBT, was not different from NBP YA.}, language = {en} } @inproceedings{RischBashfordKuligetal.2020, author = {Risch, Lucie and Bashford, Greg and Kulig, Kornelia and Kaplick, Hannes and Mayer, Frank and Cassel, Michael}, title = {Spatial frequency analysis identifies altered local Micromorphology in adolescent athletes with Achilles tendinopathy}, series = {Medicine and science in sports and exercise : MSSE ; official journal of the American College of Sports Medicine}, volume = {52}, booktitle = {Medicine and science in sports and exercise : MSSE ; official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, doi = {10.1249/01.mss.0000670932.99564.57}, pages = {82 -- 82}, year = {2020}, language = {en} } @misc{NairLinKhajooeietal.2020, author = {Nair, Alexandra and Lin, Chiao-I and Khajooei, Mina and Heikkila, Mika and Engel, Tilman and Mayer, Frank}, title = {Side comparison of knee muscle activities in response to perturbed walking of unilateral ankle instability}, series = {Medicine and science in sports and exercise : MSSE}, volume = {52}, journal = {Medicine and science in sports and exercise : MSSE}, number = {17}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, doi = {10.1249/01.mss.0000671088.10003.6b}, pages = {97 -- 97}, year = {2020}, abstract = {Acute ankle sprain leads in 40\% of all cases to chronic ankle instability (CAI). CAI is related to a variety of motor adaptations at the lower extremities. Previous investigations identified increased muscle activities while landing in CAI compared to healthy control participants. However, it remains unclear whether muscular alterations at the knee muscles are limited to the involved (unstable) ankle or are also present at the uninvolved leg. The latter might potentially indicate a risk of ankle sprain or future injury on the uninvolved leg. Purpose: To assess if there is a difference of knee muscle activities between the involved and uninvolved leg in participants with CAI during perturbed walking. Method: 10 participants (6 females; 4 males; 26±4 years; 169±9 cm; 65±7 kg) with unilateral CAI walked on a split-belt treadmill (1m/s) for 5 minutes of baseline walking and 6 minutes of perturbed walking (left and right side, each 10 perturbations). Electromyography (EMG) measurements were performed at biceps femoris (BF) and rectus femoris (RF). EMG amplitude (RMS; normalized to MVIC) were analyzed for 200ms pre-heel contact (Pre200), 100ms post heel contact (Post100) and 200ms after perturbation (Pert200). Data was analyzed by paired t-test/Wilcoxon test based on presence or absence of normal distribution (Bonferroni adjusted α level p≤ 0.0125). Results: No statistical difference was found between involved and uninvolved leg for RF (Pre200: 4±2\% and 11± 22\%, respectively, p= 0.878; Post100: 10± 5 and 18±31\%, p=0.959; Pert200: 6±3\% and 13±24\%, p=0.721) as well as for BF (Pre200: 12±7\% and 11±6, p=0.576; Post100: 10±7\% and 9±7\%, p=0.732; Pert200: 7±4 and 7±7\%, p=0.386). Discussion: No side differences in muscle activity could be revealed for assessed feedforward and feedback responses (perturbed and unperturbed) in unilateral CAI. Reduced inter-individual variability of muscular activities at the involved leg might indicate a rather stereotypical response pattern. It remains to be investigated, whether muscular control at the knee is not affected by CAI, or whether both sides adapted in a similar style to the chronic condition at the ankle.}, language = {en} } @article{MuellerEngelMuelleretal.2018, author = {Mueller, Steffen and Engel, Tilman and M{\"u}ller, Juliane and Stoll, Josefine and Baur, Heiner and Mayer, Frank}, title = {Sensorimotor exercises and enhanced trunk function}, series = {International journal of sports medicine}, volume = {39}, journal = {International journal of sports medicine}, number = {7}, publisher = {Thieme}, address = {Stuttgart}, issn = {0172-4622}, doi = {10.1055/a-0592-7286}, pages = {555 -- 563}, year = {2018}, abstract = {The aim of this study was to investigate the effect of a 6-week sensorimotor or resistance training on maximum trunk strength and response to sudden, high-intensity loading in athletes. Interventions showed no significant difference for maximum strength in concentric and eccentric testing (p>0.05). For perturbation compensation, higher peak torque response following SMT (Extension: +24Nm 95\%CI +/- 19Nm; Rotation: + 19Nm 95\%CI +/- 13Nm) and RT (Extension: +35Nm 95\%CI +/- 16Nm; Rotation: +5Nm 95\%CI +/- 4Nm) compared to CG (Extension: -4Nm 95\%CI +/- 16Nm; Rotation: -2Nm 95\%CI +/- 4Nm) was present (p<0.05).}, language = {en} } @article{WochatzRabeEngeletal.2021, author = {Wochatz, Monique and Rabe, Sophie and Engel, Tilman and M{\"u}ller, Steffen and Mayer, Frank}, title = {Scapular kinematics during unloaded and maximal loaded isokinetic concentric and eccentric shoulder flexion and extension movements}, series = {Journal of electromyography \& kinesiology : official journal of the International Society of Electrophysiology and Kinesiology}, volume = {57}, journal = {Journal of electromyography \& kinesiology : official journal of the International Society of Electrophysiology and Kinesiology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1050-6411}, doi = {10.1016/j.jelekin.2021.102517}, pages = {8}, year = {2021}, abstract = {Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms.}, language = {en} } @article{SchomoellerWeisvonBarbyetal.2019, author = {Schom{\"o}ller, Anne and Weis, Katharina and von Barby, Reena and H{\"u}bler, Axel and Mayer, Frank and Erler, Thomas}, title = {Restless legs syndrome in childhood and adolescence}, series = {Somnologie : Schlafforschung und Schlafmedizin ; Organ der Deutschen Gesellschaft f{\"u}r Schlafforschung und Schlafmedizin (DGSM)}, volume = {23}, journal = {Somnologie : Schlafforschung und Schlafmedizin ; Organ der Deutschen Gesellschaft f{\"u}r Schlafforschung und Schlafmedizin (DGSM)}, number = {2}, publisher = {Springer}, address = {Cham}, issn = {1432-9123}, doi = {10.1007/s11818-018-0188-y}, pages = {104 -- 108}, year = {2019}, language = {en} } @misc{CarlsohnScharhagRosenbergerCasseletal.2017, author = {Carlsohn, Anja and Scharhag-Rosenberger, Friederike and Cassel, Michael and Mayer, Frank}, title = {Resting Metabolic Rate in Elite Rowers and Canoeists: Difference between Indirect Calorimetry and Prediction}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-399837}, pages = {6}, year = {2017}, abstract = {Background: Athletes may differ in their resting metabolic rate (RMR) from the general population. However, to estimate the RMR in athletes, prediction equations that have not been validated in athletes are often used. The purpose of this study was therefore to verify the applicability of commonly used RMR predictions for use in athletes. Methods: The RMR was measured by indirect calorimetry in 17 highly trained rowers and canoeists of the German national teams (BMI 24 ± 2 kg/m2, fat-free mass 69 ± 15 kg). In addition, the RMR was predicted using Cunningham (CUN) and Harris-Benedict (HB) equations. A two-way repeated measures ANOVA was calculated to test for differences between predicted and measured RMR (α = 0.05). The root mean square percentage error (RMSPE) was calculated and the Bland-Altman procedure was used to quantify the bias for each prediction. Results: Prediction equations significantly underestimated the RMR in males (p < 0.001). The RMSPE was calculated to be 18.4\% (CUN) and 20.9\% (HB) in the entire group. The bias was 133 kcal/24 h for CUN and 202 kcal/24 h for HB. Conclusions: Predictions significantly underestimate the RMR in male heavyweight endurance athletes but not in females. In athletes with a high fat-free mass, prediction equations might therefore not be applicable to estimate energy requirements. Instead, measurement of the resting energy expenditure or specific prediction equations might be needed for the individual heavyweight athlete.}, language = {en} } @article{CarlsohnScharhagRosenbergerCasseletal.2011, author = {Carlsohn, Anja and Scharhag-Rosenberger, Friederike and Cassel, Michael and Mayer, Frank}, title = {Resting metabolic rate in elite rowers and canoeists difference between indirect calorimetry and prediction}, series = {Annals of nutrition \& metabolism : journal of nutrition, metabolic diseases and dietetics ; an official journal of International Union of Nutritional Sciences (IUNS)}, volume = {58}, journal = {Annals of nutrition \& metabolism : journal of nutrition, metabolic diseases and dietetics ; an official journal of International Union of Nutritional Sciences (IUNS)}, number = {3}, publisher = {Karger}, address = {Basel}, issn = {0250-6807}, doi = {10.1159/000330119}, pages = {239 -- 244}, year = {2011}, abstract = {Background: Athletes may differ in their resting metabolic rate (RMR) from the general population. However, to estimate the RMR in athletes, prediction equations that have not been validated in athletes are often used. The purpose of this study was therefore to verify the applicability of commonly used RMR predictions for use in athletes. Methods: The RMR was measured by indirect calorimetry in 17 highly trained rowers and canoeists of the German national teams (BMI 24 +/- 2 kg/m(2), fat-free mass 69 +/- 15 kg). In addition, the RMR was predicted using Cunningham (CUN) and Harris-Benedict (HB) equations. A two-way repeated measures ANOVA was calculated to test for differences between predicted and measured RMR (alpha = 0.05). The root mean square percentage error (RMSPE) was calculated and the Bland-Altman procedure was used to quantify the bias for each prediction. Results: Prediction equations significantly underestimated the RMR in males (p < 0.001). The RMSPE was calculated to be 18.4\% (CUN) and 20.9\% (HB) in the entire group. The bias was 133 kcal/24 h for CUN and 202 kcal/24 h for HB. Conclusions: Predictions significantly underestimate the RMR in male heavyweight endurance athletes but not in females. In athletes with a high fat-free mass, prediction equations might therefore not be applicable to estimate energy requirements. Instead, measurement of the resting energy expenditure or specific prediction equations might be needed for the individual heavyweight athlete.}, language = {en} } @misc{AppiahDwomohMuellerMayer2018, author = {Appiah-Dwomoh, Edem Korkor and M{\"u}ller, Steffen and Mayer, Frank}, title = {Reproducibility of Static and Dynamic Postural Control Measurement in Adolescent Athletes with Back Pain}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {470}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-417526}, pages = {8}, year = {2018}, abstract = {Static (one-legged stance) and dynamic (star excursion balance) postural control tests were performed by 14 adolescent athletes with and 17 without back pain to determine reproducibility. The total displacement, mediolateral and anterior-posterior displacements of the centre of pressure in mm for the static, and the normalized and composite reach distances for the dynamic tests were analysed. Intraclass correlation coefficients, 95\% confidence intervals, and a Bland-Altman analysis were calculated for reproducibility. Intraclass correlation coefficients for subjects with (0.54 to 0.65), (0.61 to 0.69) and without (0.45 to 0.49), (0.52 to 0.60) back pain were obtained on the static test for right and left legs, respectively. Likewise, (0.79 to 0.88), (0.75 to 0.93) for subjects with and (0.61 to 0.82), (0.60 to 0.85) for those without back pain were obtained on the dynamic test for the right and left legs, respectively. Systematic bias was not observed between test and retest of subjects on both static and dynamic tests. The one-legged stance and star excursion balance tests have fair to excellent reliabilities on measures of postural control in adolescent athletes with and without back pain. They can be used as measures of postural control in adolescent athletes with and without back pain.}, language = {en} } @article{AppiahDwomohMuellerMayer2018, author = {Appiah-Dwomoh, Edem Korkor and M{\"u}ller, Steffen and Mayer, Frank}, title = {Reproducibility of Static and Dynamic Postural Control Measurement in Adolescent Athletes with Back Pain}, series = {Rehabilitation Research and Practice}, volume = {2018}, journal = {Rehabilitation Research and Practice}, publisher = {Hindawi}, address = {New York}, issn = {2090-2875}, doi = {10.1155/2018/8438350}, pages = {1 -- 8}, year = {2018}, abstract = {Static (one-legged stance) and dynamic (star excursion balance) postural control tests were performed by 14 adolescent athletes with and 17 without back pain to determine reproducibility. The total displacement, mediolateral and anterior-posterior displacements of the centre of pressure in mm for the static, and the normalized and composite reach distances for the dynamic tests were analysed. Intraclass correlation coefficients, 95\% confidence intervals, and a Bland-Altman analysis were calculated for reproducibility. Intraclass correlation coefficients for subjects with (0.54 to 0.65), (0.61 to 0.69) and without (0.45 to 0.49), (0.52 to 0.60) back pain were obtained on the static test for right and left legs, respectively. Likewise, (0.79 to 0.88), (0.75 to 0.93) for subjects with and (0.61 to 0.82), (0.60 to 0.85) for those without back pain were obtained on the dynamic test for the right and left legs, respectively. Systematic bias was not observed between test and retest of subjects on both static and dynamic tests. The one-legged stance and star excursion balance tests have fair to excellent reliabilities on measures of postural control in adolescent athletes with and without back pain. They can be used as measures of postural control in adolescent athletes with and without back pain.}, language = {en} } @article{WochatzRabeWolteretal.2017, author = {Wochatz, Monique and Rabe, Sophie and Wolter, Martin and Engel, Tilman and Mueller, Steffen and Mayer, Frank}, title = {Reproducibility of scapular muscle activity in isokinetic shoulder flexion and extension}, series = {Journal of electromyography and kinesiology}, volume = {34}, journal = {Journal of electromyography and kinesiology}, publisher = {Elsevier}, address = {Oxford}, issn = {1050-6411}, doi = {10.1016/j.jelekin.2017.04.006}, pages = {86 -- 92}, year = {2017}, abstract = {Repetitive overhead movements have been identified as a main risk factor to develop shoulder complaints with scapular muscle activity being altered. Reliable assessment of muscle activity is essential to differentiate between symptomatic and asymptomatic individuals. Therefore, the present study aimed to investigate the intra-and inter-session reliability of scapular muscle activity during maximal isokinetic shoulder flexion and extension. Eleven asymptomatic adults performed maximum effort isokinetic shoulder flexion and extension (concentric and eccentric at 60 degrees/s) in a test-retest design. Muscle activity of the upper and lower trapezius and serratus anterior was assessed by sEMG. Root Mean Square was calculated for whole ROM and single movement phases of absolute and normalized muscle activity. Absolute (Bland-Altman analysis (Bias, LoA), Minimal detectable change (MDC)) and relative reliability parameters (Intraclass correlation coefficient (ICC), coefficient of variation (CV)/test-retest variability (TRV)) were utilized for the evaluation of reproducibility. Intra-session reliability revealed ICCs between 0.56 and 0.98, averaged CVs of 18\% and average MDCs of 81 mV. Inter-session reliability resulted in ICCs between 0.13 and 0.93, averaged TRVs of 21\%, average MDCs of 15\% and systematic and random error between -8 +/- 60\% and 12 +/- 36\%. Scapular muscle activity assessed in overhead movements can be measured reliably under maximum load conditions, though variability is dependent on the movement phase. Measurement variability does not exceed magnitudes of altered scapular muscle activities as reported in previous studies. Therefore, maximum load application is a promising approach for the evaluation of changes in scapular control related to pathologies. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{RectorIntziegianniMuelleretal.2017, author = {Rector, Michael V. and Intziegianni, Konstantina and M{\"u}ller, Steffen and Mayer, Frank and Cassel, Michael}, title = {Reproducibility of an ankle joint rotation correction method for assessment of Achilles tendon elongation}, series = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, volume = {25}, journal = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, number = {1}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0959-3020}, doi = {10.3233/IES-160644}, pages = {47 -- 52}, year = {2017}, abstract = {BACKGROUND: The Achilles tendon (AT) requires optimal material and mechanical properties to function properly. Calculation of these properties depends on accurate measurement of input parameters (i.e. tendon elongation). However, the measurement of AT elongation with ultrasound during maximum voluntary isometric contraction (MVIC) is overestimated by ankle joint rotation (AJR). Methods to correct the influence of this rotation on AT elongation exist, yet their reproducibility in clinical settings is unknown. OBJECTIVE: To evaluate the test-retest reproducibility of AT elongation during MVIC after AJR correction. METHODS: Ten participants attended test and retest measurements where they performed plantar-flexion MVIC on a dynamometer. Simultaneously, ultrasound recorded AT elongation as the displacement of the medial gastrocnemius-myotendinous junction, while an electrogoniometer measured AJR. The ankle was then passively rotated to the AJR achieved during MVIC and AT elongation again determined. Elongation was corrected by subtracting this passive AT elongation from the total AT elongation during MVIC. Reproducibility was evaluated using ICC (2.1), test-retest variability (TRV, \%), Bland-Altman analyses (Bias +/- LoA [1.96*SD]) and standard error of the measurement (SEM). RESULTS: Corrected AT elongation reproducibility exhibited an ICC = 0.79, SEM = 0.2 cm and TRV = 20 +/- 19\%. Bias +/- LoA were determined to be 0.0 +/- 0.8 cm. CONCLUSIONS: Using this ultrasound and electrogoniometer-based method, corrected AT elongation can be assessed reproducibly.}, language = {en} } @misc{BisiBalogunCasselMayer2017, author = {Bisi-Balogun, Adebisi and Cassel, Michael and Mayer, Frank}, title = {Reliability of various measurement stations for determining plantar fascia thickness and echogenicity}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-400615}, pages = {11}, year = {2017}, abstract = {This study aimed to determine the relative and absolute reliability of ultrasound (US) measurements of the thickness and echogenicity of the plantar fascia (PF) at different measurement stations along its length using a standardized protocol. Twelve healthy subjects (24 feet) were enrolled. The PF was imaged in the longitudinal plane. Subjects were assessed twice to evaluate the intra-rater reliability. A quantitative evaluation of the thickness and echogenicity of the plantar fascia was performed using Image J, a digital image analysis and viewer software. A sonography evaluation of the thickness and echogenicity of the PF showed a high relative reliability with an Intra class correlation coefficient of 0.88 at all measurement stations. However, the measurement stations for both the PF thickness and echogenicity which showed the highest intraclass correlation coefficient (ICCs) did not have the highest absolute reliability. Compared to other measurement stations, measuring the PF thickness at 3 cm distal and the echogenicity at a region of interest 1 cm to 2 cm distal from its insertion at the medial calcaneal tubercle showed the highest absolute reliability with the least systematic bias and random error. Also, the reliability was higher using a mean of three measurements compared to one measurement. To reduce discrepancies in the interpretation of the thickness and echogenicity measurements of the PF, the absolute reliability of the different measurement stations should be considered in clinical practice and research rather than the relative reliability with the ICC.}, language = {en} } @article{BisiBalogunCasselMayer2016, author = {Bisi-Balogun, Adebisi and Cassel, Michael and Mayer, Frank}, title = {Reliability of Various Measurement Stations for Determining Plantar Fascia Thickness and Echogenicity}, series = {Diagnostics : open access journal}, volume = {6}, journal = {Diagnostics : open access journal}, publisher = {MDPI}, address = {Basel}, issn = {2075-4418}, doi = {10.3390/diagnostics6020015}, pages = {506 -- 519}, year = {2016}, abstract = {This study aimed to determine the relative and absolute reliability of ultrasound (US) measurements of the thickness and echogenicity of the plantar fascia (PF) at different measurement stations along its length using a standardized protocol. Twelve healthy subjects (24 feet) were enrolled. The PF was imaged in the longitudinal plane. Subjects were assessed twice to evaluate the intra-rater reliability. A quantitative evaluation of the thickness and echogenicity of the plantar fascia was performed using Image J, a digital image analysis and viewer software. A sonography evaluation of the thickness and echogenicity of the PF showed a high relative reliability with an Intra class correlation coefficient of 0.88 at all measurement stations. However, the measurement stations for both the PF thickness and echogenicity which showed the highest intraclass correlation coefficient (ICCs) did not have the highest absolute reliability. Compared to other measurement stations, measuring the PF thickness at 3 cm distal and the echogenicity at a region of interest 1 cm to 2 cm distal from its insertion at the medial calcaneal tubercle showed the highest absolute reliability with the least systematic bias and random error. Also, the reliability was higher using a mean of three measurements compared to one measurement. To reduce discrepancies in the interpretation of the thickness and echogenicity measurements of the PF, the absolute reliability of the different measurement stations should be considered in clinical practice and research rather than the relative reliability with the ICC.}, language = {en} } @inproceedings{IntziegianniCasselKoenigetal.2013, author = {Intziegianni, Konstantina and Cassel, Michael and K{\"o}nig, Niklas and Mayer, Frank}, title = {Reliability of variables defining mechanical and material properties of the achilles tendon}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {238 -- 239}, year = {2013}, language = {en} } @inproceedings{KopinskiEngelCasseletal.2014, author = {Kopinski, Stephan and Engel, Tilman and Cassel, Michael and Carlsohn, Anja and Mayer, Frank}, title = {Reliability of ultrasound measurements for subcutaneous adipose tissue in elite canoe athletes}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {46}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {539 -- 539}, year = {2014}, language = {en} } @article{BuschBangerterMayeretal.2023, author = {Busch, Aglaja and Bangerter, Christian and Mayer, Frank and Baur, Heiner}, title = {Reliability of the active knee joint position sense test and influence of limb dominance and sex}, series = {Scientific reports}, volume = {13}, journal = {Scientific reports}, publisher = {Macmillan Publishers Limited, part of Springer Nature}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-022-26932-2}, pages = {10}, year = {2023}, abstract = {The output of a sensorimotor performance can be measured with the joint position sense (JPS) test. However, investigations of leg dominance, sex and quality measures on this test are limited. Therefore, these potential influencing factors as well as reliability and consistency measures were evaluated for angular reproduction performance and neuromuscular activity during the active knee JPS test in healthy participants. Twenty healthy participants (10 males; 10 females; age 29 +/- 8 years; height 165 +/- 39 cm; body mass 69 +/- 13 kg) performed a seated knee JPS test with a target angle of 50 degrees. Measurements were conducted in two sessions separated by two weeks and consisted of two blocks of continuous angular reproduction (three minutes each block). The difference between reproduced and target angle was identified as angular error measured by an electrogoniometer. During reproduction, the neuromuscular activity of the quadriceps muscle was assessed by surface electromyography. Neuromuscular activity was normalized to submaximal voluntary contraction (subMVC) and displayed per muscle and movement phase. Differences between leg dominance and sex were calculated using Friedman-test (alpha = 0.05). Reliability measures including intraclass correlation coefficient (ICC), Bland-Altman analysis (bias +/- limits of agreement (LoA)) and minimal detectable change (MDC) were analysed. No significant differences between leg dominance and sex were found in angular error and neuromuscular activity. Angular error demonstrated inter-session ICC scores of 0.424 with a bias of 2.4 degrees (+/- 2.4 degrees LoA) as well as MDC of 6.8 degrees and moderate intra-session ICC (0.723) with a bias of 1.4 degrees (+/- 1.65 degrees LoA) as well as MDC of 4.7 degrees. Neuromuscular activity for all muscles and movement phases illustrated inter-session ICC ranging from 0.432 to 0.809 with biases between - 2.5 and 13.6\% subMVC and MDC from 13.4 to 63.9\% subMVC. Intra-session ICC ranged from 0.705 to 0.987 with biases of - 7.7 to 2.4\% subMVC and MDC of 2.7 to 46.5\% subMVC. Leg dominance and sex seem not to influence angular reproduction performance and neuromuscular activity. Poor to excellent relative reliability paired with an acceptable consistency confirm findings of previous studies. Comparisons to pathological populations should be conducted with caution.}, language = {en} } @inproceedings{IntziegianniCasselHainetal.2014, author = {Intziegianni, Konstantina and Cassel, Michael and Hain, Gerrit and Fr{\"o}hlic, Katja and Mayer, Frank}, title = {Reliability of sonographic assessment of Achilles tendon cross-sectional area at rest and maximal voluntary contraction}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {46}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {47 -- 47}, year = {2014}, language = {en} } @article{RischWochatzMesserschmidtetal.2017, author = {Risch, Lucie and Wochatz, Monique and Messerschmidt, Janin and Engel, Tilman and Mayer, Frank and Cassel, Michael}, title = {Reliability of evaluating achilles tendon vascularization assessed with doppler ultrasound advanced dynamic flow}, series = {Journal of ultrasound in medicine}, volume = {37}, journal = {Journal of ultrasound in medicine}, number = {3}, publisher = {Wiley}, address = {Hoboken}, issn = {0278-4297}, doi = {10.1002/jum.14414}, pages = {737 -- 744}, year = {2017}, abstract = {The reliability of quantifying intratendinous vascularization by high-sensitivity Doppler ultrasound advanced dynamic flow has not been examined yet. Therefore, this study aimed to investigate the intraobserver and interobserver reliability of evaluating Achilles tendon vascularization by advanced dynamic flow using established scoring systems. Methods-Three investigators evaluated vascularization in 67 recordings in a test-retest design, applying the Ohberg score, a modified Ohberg score, and a counting score. Intraobserver and interobserver agreement for the Ohberg score and modified Ohberg score was analyzed by the Cohen kappa and Fleiss kappa coefficients (absolute), Kendall tau b coefficient, and Kendall coefficient of concordance (W; relative). The reliability of the counting score was analyzed by intraclass correlation coefficients (ICC) 2.1 and 3.1, the standard error of measurement (SEM), and Bland-Altman analysis (bias and limits of agreement [LoA]). Results-Intraobserver and interobserver agreement (absolute/relative) ranged from 0.61 to 0.87/0.87 to 0.95 and 0.11 to 0.66/0.76 to 0.89 for the Ohberg score and from 0.81 to 0.87/0.92 to 0.95 and 0.64 to 0.80/0.88 to 0.93 for the modified Ohberg score, respectively. The counting score revealed an intraobserver ICC of 0.94 to 0.97 (SEM, 1.0-1.5; bias, -1; and LoA, 3-4 vessels). The interobserver ICC for the counting score ranged from 0.91 to 0.98 (SEM, 1.0-1.9; bias, 0; and LoA, 3-5 vessels). Conclusions-The modified Ohberg score and counting score showed excellent reliability and seem convenient for research and clinical practice. The Ohberg score revealed decent intraobserver but unexpected low interobserver reliability and therefore cannot be recommended.}, language = {en} } @inproceedings{HainMuellerMuelleretal.2013, author = {Hain, Gerrit and M{\"u}ller, Juliane and M{\"u}ller, Steffen and Reschke, Antje and Mayer, Frank}, title = {Reliability of an in-vivo 3-segmental kinematic trunk model in a one-handed lifting task}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {45}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {174 -- 174}, year = {2013}, language = {en} } @article{WochatzTilgnerMuelleretal.2019, author = {Wochatz, Monique and Tilgner, Nina and Mueller, Steffen and Rabe, Sophie and Eichler, Sarah and John, Michael and V{\"o}ller, Heinz and Mayer, Frank}, title = {Reliability and validity of the Kinect V2 for the assessment of lower extremity rehabilitation exercises}, series = {Gait \& posture}, volume = {70}, journal = {Gait \& posture}, publisher = {Elsevier}, address = {Clare}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2019.03.020}, pages = {330 -- 335}, year = {2019}, abstract = {Research question: The purpose of this study was to evaluate the test-retest reliability of lower extremity kinematics during squat, hip abduction and lunge exercises captured by the Kinect and to evaluate the agreement to a reference 3D camera-based motion system. Methods: Twenty-one healthy individuals performed five repetitions of each lower limb exercise on two different days. Movements were simultaneously assessed by the Kinect and the reference 3D motion system. Joint angles and positions of the lower limb were calculated for sagittal and frontal plane. For the inter-session reliability and the agreement between the two systems standard error of measurement (SEM), bias with limits of agreement (LoA) and Pearson Correlation Coefficient (r) were calculated. Results: Parameters indicated varying reliability for the assessed joint angles and positions and decreasing reliability with increasing task complexity. Across all exercises, measurement deviations were shown especially for small movement amplitudes. Variability was acceptable for joint angles and positions during the squat, partially acceptable during the hip abduction and predominately inacceptable during the lunge. The agreement between systems was characterized by systematic errors. Overestimations by the Kinect were apparent for hip flexion during the squat and hip abduction/adduction during the hip abduction exercise as well as for the knee positions during the lunge. Knee and hip flexion during hip abduction and lunge were underestimated by the Kinect. Significance: The Kinect system can reliably assess lower limb joint angles and positions during simple exercises. The validity of the system is however restricted. An application in the field of early orthopedic rehabilitation without further development of post-processing techniques seems so far limited.}, language = {en} } @article{SilveiraCarlsohnLangenetal.2016, author = {Silveira, Raul De Souza and Carlsohn, Anja and Langen, Georg and Mayer, Frank and Scharhag-Rosenberger, Friederike}, title = {Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry}, series = {Journal of the International Society of Sports Nutrition}, volume = {13}, journal = {Journal of the International Society of Sports Nutrition}, publisher = {BioMed Central}, address = {London}, issn = {1550-2783}, doi = {10.1186/s12970-016-0115-1}, pages = {7}, year = {2016}, abstract = {Background: Exercising at intensities where fat oxidation rates are high has been shown to induce metabolic benefits in recreational and health-oriented sportsmen. The exercise intensity (Fat(peak)) eliciting peak fat oxidation rates is therefore of particular interest when aiming to prescribe exercise for the purpose of fat oxidation and related metabolic effects. Although running and walking are feasible and popular among the target population, no reliable protocols are available to assess Fat(peak) as well as its actual velocity (VPFO) during treadmill ergometry. Our purpose was therefore, to assess the reliability and day-to-day variability of VPFO and Fat(peak) during treadmill ergometry running. Conclusion: In summary, relative and absolute reliability indicators for V-PFO and Fat(peak) were found to be excellent. The observed LoA may now serve as a basis for future training prescriptions, although fat oxidation rates at prolonged exercise bouts at this intensity still need to be investigated.}, language = {en} } @misc{DeSouzaSilveiraCarlsohnLangenetal.2016, author = {De Souza Silveira, Raul and Carlsohn, Anja and Langen, Georg and Mayer, Frank and Scharhag-Rosenberger, Friederike}, title = {Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {423}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-407334}, pages = {7}, year = {2016}, abstract = {Background: Exercising at intensities where fat oxidation rates are high has been shown to induce metabolic benefits in recreational and health-oriented sportsmen. The exercise intensity (Fat peak ) eliciting peak fat oxidation rates is therefore of particular interest when aiming to prescribe exercise for the purpose of fat oxidation and related metabolic effects. Although running and walking are feasible and popular among the target population, no reliable protocols are available to assess Fat peak as well as its actual velocity (V PFO ) during treadmill ergometry. Our purpose was therefore, to assess the reliability and day-to-day variability of V PFO and Fat peak during treadmill ergometry running. Methods: Sixteen recreational athletes (f = 7, m = 9; 25 ± 3 y; 1.76 ± 0.09 m; 68.3 ± 13.7 kg; 23.1 ± 2.9 kg/m 2 ) performed 2 different running protocols on 3 different days with standardized nutrition the day before testing. At day 1, peak oxygen uptake (VO 2peak ) and the velocities at the aerobic threshold (V LT ) and respiratory exchange ratio (RER) of 1.00 (V RER ) were assessed. At days 2 and 3, subjects ran an identical submaximal incremental test (Fat-peak test) composed of a 10 min warm-up (70 \% V LT ) followed by 5 stages of 6 min with equal increments (stage 1 = V LT , stage 5 = V RER ). Breath-by-breath gas exchange data was measured continuously and used to determine fat oxidation rates. A third order polynomial function was used to identify V PFO and subsequently Fat peak . The reproducibility and variability of variables was verified with an int raclass correlation coef ficient (ICC), Pearson ' s correlation coefficient, coefficient of variation (CV) an d the mean differences (bias) ± 95 \% limits of agreement (LoA). Results: ICC, Pearson ' s correlation and CV for V PFO and Fat peak were 0.98, 0.97, 5.0 \%; and 0.90, 0.81, 7.0 \%, respectively. Bias ± 95 \% LoA was - 0.3 ± 0.9 km/h for V PFO and - 2±8\%ofVO 2peak for Fat peak. Conclusion: In summary, relative and absolute reliability indicators for V PFO and Fat peak were found to be excellent. The observed LoA may now serve as a basis for future training prescriptions, although fat oxidation rates at prolonged exercise bouts at this intensity still need to be investigated.}, language = {en} } @inproceedings{SilveiraCarlsohnLangenetal.2014, author = {Silveira, Raul De Souza and Carlsohn, Anja and Langen, Georg and Otto, Christoph and Hain, Gerrit and Mayer, Frank}, title = {Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {46}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {631 -- 632}, year = {2014}, language = {en} } @article{BaurMuellerHirschmuelleretal.2006, author = {Baur, Heiner and M{\"u}ller, Steffen and Hirschm{\"u}ller, Anja and Huber, Georg and Mayer, Frank}, title = {Reactivity, stability, and strength performance capacity in motor sports}, series = {British journal of sports medicine : the journal of sport and exercise medicine}, volume = {40}, journal = {British journal of sports medicine : the journal of sport and exercise medicine}, publisher = {BMJ Publ. Group}, address = {London}, issn = {0306-3674}, doi = {10.1136/bjsm.2006.025783}, pages = {906 -- 910}, year = {2006}, abstract = {Background: Racing drivers require multifaceted cognitive and physical abilities in a multitasking situation. A knowledge of their physical capacities may help to improve fitness and performance. Objective: To compare reaction time, stability performance capacity, and strength performance capacity of elite racing drivers with those of age-matched, physically active controls. Methods: Eight elite racing drivers and 10 physically active controls matched for age and weight were tested in a reaction and determination test requiring upper and lower extremity responses to visual and audio cues. Further tests comprised evaluation of one-leg postural stability on a two-dimensional moveable platform, measures of maximum strength performance capacity of the extensors of the leg on a leg press, and a test of force capacity of the arms in a sitting position at a steering wheel. An additional arm endurance test consisted of isometric work at the steering wheel at + 30 degrees and -30 degrees where an eccentric threshold load of 30 N.m was applied. Subjects had to hold the end positions above this threshold until exhaustion. Univariate one way analysis of variance (alpha = 0.05) including a Bonferroni adjustment was used to detect group differences between the drivers and controls. Results: The reaction time of the racing drivers was significantly faster than the controls ( p = 0.004). The following motor reaction time and reaction times in the multiple determination test did not differ between the groups. No significant differences (p> 0.05) were found for postural stability, leg extensor strength, or arm strength and endurance. Conclusions: Racing drivers have faster reaction times than age-matched physically active controls. Further development of motor sport-specific test protocols is suggested. According to the requirements of motor racing, strength and sensorimotor performance capacity can potentially be improved.}, language = {en} } @article{WippertArampatzisBanzeretal.2019, author = {Wippert, Pia-Maria and Arampatzis, Adamantios and Banzer, Winfried and Beck, Heidrun and Hasenbring, Monika Ilona and Schiltenwolf, Marcus and Schneider, Christian and Stengel, Dirk and Platen, Petra and Mayer, Frank}, title = {Psychosoziale Risikofaktoren in der Entstehung von chronisch unspezifischen R{\"u}ckenschmerzen}, series = {Zeitschrift f{\"u}r Sportpsychologie}, volume = {26}, journal = {Zeitschrift f{\"u}r Sportpsychologie}, number = {1}, publisher = {Hogrefe}, address = {G{\"o}ttingen}, issn = {1612-5010}, doi = {10.1026/1612-5010/a000245}, pages = {25 -- 35}, year = {2019}, abstract = {Chronisch unspezifische R{\"u}ckenschmerzen (CURS) geh{\"o}ren international zu den h{\"a}ufigsten Schmerzph{\"a}nomenen und k{\"o}nnen f{\"u}r Athletinnen und Athleten karrierelimitierend sein. Knapp ein Drittel der j{\"a}hrlichen Trainingsausfallzeiten werden auf CURS zur{\"u}ckgef{\"u}hrt. In der Entstehung von chronischen Schmerzen ist ein multifaktorielles {\"A}tiologiemodell mit einem signifikanten Einfluss psychosozialer Risikofaktoren evident. Obwohl dies in der Allgemeinbev{\"o}lkerung bereits gut erforscht ist, gibt es in der Sportwissenschaft vergleichsweise wenige Arbeiten dar{\"u}ber. Dieses Thema wird daher in drei Multicenterstudien und zahlreichen Teilstudien des MiSpEx-Netzwerks (Medicine in Spine-Exercise-Network, F{\"o}rderzeitraum 2011 - 2018) aufgegriffen. Entsprechend der Empfehlung einer fr{\"u}hzeitigen Diagnostik von Chronifizierungsfaktoren in der „Nationalen Versorgungsleitlinie Kreuzschmerz", besch{\"a}ftigt sich das Netzwerk u. a. mit der {\"U}berpr{\"u}fung, Entwicklung und Evaluation diagnostischer M{\"o}glichkeiten. Der vorliegende Beitrag beschreibt die Entwicklung einer Diagnostik von psychosozialen Risikofaktoren, die einerseits eine Einsch{\"a}tzung des Risikos der Entwicklung von CURS und andererseits eine individuelle Zuweisung zu (Trainings)Interventionen erlaubt. Es wird die Entwicklungsrationale beschrieben und dabei verschiedene methodische Herangehensweisen und Entscheidungssequenzen reflektiert.}, language = {de} } @misc{WippertNiedererDriessleinetal.2021, author = {Wippert, Pia-Maria and Niederer, Daniel and Drießlein, David and Beck, Heidrun and Banzer, Winfried Eberhard and Schneider, Christian and Schiltenwolf, Marcus and Mayer, Frank}, title = {Psychosocial Moderators and Mediators of Sensorimotor Exercise in Low Back Pain: A Randomized Multicenter Controlled Trial}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1866-8364}, doi = {10.25932/publishup-54327}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-543277}, pages = {1 -- 16}, year = {2021}, abstract = {The effects of exercise interventions on unspecific chronic low back pain (CLBP) have been investigated in many studies, but the results are inconclusive regarding exercise types, efficiency, and sustainability. This may be because the influence of psychosocial factors on exercise induced adaptation regarding CLBP is neglected. Therefore, this study assessed psychosocial characteristics, which moderate and mediate the effects of sensorimotor exercise on LBP. A single-blind 3-arm multicenter randomized controlled trial was conducted for 12-weeks. Three exercise groups, sensorimotor exercise (SMT), sensorimotor and behavioral training (SMT-BT), and regular routines (CG) were randomly assigned to 662 volunteers. Primary outcomes (pain intensity and disability) and psychosocial characteristics were assessed at baseline (M1) and follow-up (3/6/12/24 weeks, M2-M5). Multiple regression models were used to analyze whether psychosocial characteristics are moderators of the relationship between exercise and pain, meaning that psychosocial factors and exercise interact. Causal mediation analysis were conducted to analyze, whether psychosocial characteristics mediate the exercise effect on pain. A total of 453 participants with intermittent pain (mean age = 39.5 ± 12.2 years, f = 62\%) completed the training. It was shown, that depressive symptomatology (at M4, M5), vital exhaustion (at M4), and perceived social support (at M5) are significant moderators of the relationship between exercise and the reduction of pain intensity. Further depressive mood (at M4), social-satisfaction (at M4), and anxiety (at M5 SMT) significantly moderate the exercise effect on pain disability. The amount of moderation was of clinical relevance. In contrast, there were no psychosocial variables which mediated exercise effects on pain. In conclusion it was shown, that psychosocial variables can be moderators in the relationship between sensorimotor exercise induced adaptation on CLBP which may explain conflicting results in the past regarding the merit of exercise interventions in CLBP. Results suggest further an early identification of psychosocial risk factors by diagnostic tools, which may essential support the planning of personalized exercise therapy. Level of Evidence: Level I. Clinical Trial Registration: DRKS00004977, LOE: I, MiSpEx: grant-number: 080102A/11-14. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML\&TRIAL_ID=DRKS00004977.}, language = {en} } @article{WippertNiedererDriessleinetal.2020, author = {Wippert, Pia-Maria and Niederer, Daniel and Drießlein, David and Beck, Heidrun and Banzer, Winfried Eberhard and Schneider, Christian and Schiltenwolf, Marcus and Mayer, Frank}, title = {Psychosocial Moderators and Mediators of Sensorimotor Exercise in Low Back Pain: A Randomized Multicenter Controlled Trial}, series = {Frontiers in Psychiatry}, volume = {12}, journal = {Frontiers in Psychiatry}, publisher = {Frontiers Research Foundation}, address = {Lausanne, Schweiz}, issn = {1664-0640}, doi = {10.3389/fpsyt.2021.629474}, pages = {1 -- 16}, year = {2020}, abstract = {The effects of exercise interventions on unspecific chronic low back pain (CLBP) have been investigated in many studies, but the results are inconclusive regarding exercise types, efficiency, and sustainability. This may be because the influence of psychosocial factors on exercise induced adaptation regarding CLBP is neglected. Therefore, this study assessed psychosocial characteristics, which moderate and mediate the effects of sensorimotor exercise on LBP. A single-blind 3-arm multicenter randomized controlled trial was conducted for 12-weeks. Three exercise groups, sensorimotor exercise (SMT), sensorimotor and behavioral training (SMT-BT), and regular routines (CG) were randomly assigned to 662 volunteers. Primary outcomes (pain intensity and disability) and psychosocial characteristics were assessed at baseline (M1) and follow-up (3/6/12/24 weeks, M2-M5). Multiple regression models were used to analyze whether psychosocial characteristics are moderators of the relationship between exercise and pain, meaning that psychosocial factors and exercise interact. Causal mediation analysis were conducted to analyze, whether psychosocial characteristics mediate the exercise effect on pain. A total of 453 participants with intermittent pain (mean age = 39.5 ± 12.2 years, f = 62\%) completed the training. It was shown, that depressive symptomatology (at M4, M5), vital exhaustion (at M4), and perceived social support (at M5) are significant moderators of the relationship between exercise and the reduction of pain intensity. Further depressive mood (at M4), social-satisfaction (at M4), and anxiety (at M5 SMT) significantly moderate the exercise effect on pain disability. The amount of moderation was of clinical relevance. In contrast, there were no psychosocial variables which mediated exercise effects on pain. In conclusion it was shown, that psychosocial variables can be moderators in the relationship between sensorimotor exercise induced adaptation on CLBP which may explain conflicting results in the past regarding the merit of exercise interventions in CLBP. Results suggest further an early identification of psychosocial risk factors by diagnostic tools, which may essential support the planning of personalized exercise therapy. Level of Evidence: Level I. Clinical Trial Registration: DRKS00004977, LOE: I, MiSpEx: grant-number: 080102A/11-14. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML\&TRIAL_ID=DRKS00004977.}, language = {en} } @article{CasselBaurHirschmuelleretal.2015, author = {Cassel, Michael and Baur, Heiner and Hirschmueller, Anja and Carlsohn, Anja and Fr{\"o}hlich, Katja and Mayer, Frank}, title = {Prevalence of Achilles and patellar tendinopathy and their association to intratendinous changes in adolescent athletes}, series = {Scandinavian journal of medicine \& science in sports}, volume = {25}, journal = {Scandinavian journal of medicine \& science in sports}, number = {3}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0905-7188}, doi = {10.1111/sms.12318}, pages = {e310 -- e318}, year = {2015}, abstract = {Achilles (AT) and patellar tendons (PT) are commonly affected by tendinopathy in adult athletes but prevalence of symptoms and morphological changes in adolescents is unclear. The study aimed to determine prevalence of tendinopathy and intratendinous changes in ATs and PTs of adolescent athletes. A total of 760 adolescent athletes (13.0 +/- 1.9 years; 160 +/- 13cm; 50 +/- 14kg) were examined. History, local clinical examination, and longitudinal Doppler ultrasound analysis for both ATs and PTs were performed including identification of intratendinous echoic changes and vascularization. Diagnosis of tendinopathy was complied clinically in case of positive history of tendon pain and tendon pain on palpation. Achilles tendinopathy was diagnosed in 1.8\% and patellar tendinopathy in 5.8\%. Vascularizations were visible in 3.0\% of ATs and 11.4\% of PTs, hypoechogenicities in 0.7\% and 3.2\% as well as hyperechogenicities in 0\% and 0.3\%, respectively. Vascularizations and hypoechogenicities were statistically significantly more often in males than in females (P0.02). Subjects with patellar tendinopathy had higher prevalence of structural intratendinous changes than those without PT symptoms (P0.001). In adolescent athletes, patellar tendinopathy is three times more frequent compared with Achilles tendinopathy. Longitudinal studies are necessary to investigate physiological or pathological origin of vascularizations and its predictive value in development of tendinopathy.}, language = {en} } @article{HirschmuellerFreyDeibertetal.2010, author = {Hirschmueller, Anja and Frey, Virginie and Deibert, Peter and Konstantinidis, Lukas and Mayer, Frank and Suedkamp, Norbert and Helwig, Peter}, title = {Powerdopplersonografische Befunde der Achillessehnen von 953 Langstreckenlaeufern : eine Querschnittsstudie}, issn = {0172-4614}, doi = {10.1055/s-0029-1245189}, year = {2010}, abstract = {Aim: The aim of this cross-sectional study was to assess the frequency of tendinopathy-typical Doppler sonographic changes in the Achilles tendons of long distance runners and to correlate these findings with anamnestic and anthropometric data of the subjects. Materials and Methods: 1906 Achilles tendons of 953 long distance runners were examined by ultrasound and power Doppler (Toshiba Aplio SSA-770A/80 12 MHz). Ultrasound images (spindle-shaped thickening, hypoechoic/hyperechoic lesions, neovascularizations) were analyzed in relation to the runners' anthropometrical data and history of Achilles tendon complaints. Results: In asymptomatic runners as well as in the overall group, there was a statistically significant correlation between tendon thickness and age, height and weight (CC 0.24 - 0.38, p < 0.001). Runners with current or healed Achilles tendon complaints displayed a statistically significant thickening of the tendons, as well as an increase in hypoechoic lesions and neovascularizations (p < 0.001). While grayscale abnormalities were rarely found in asymptomatic runners (< 10\%), neovascularization was detected in 35\% of healthy test persons using the high-resolution power Doppler "Advanced Dynamic Flow". Conclusion: Contrary to frequent assumption, neovascularization is often found in tendons of asymptomatic runners, using modern power Doppler equipment. The pathological relevance of single microvessels in asymptomatic tendons must, therefore, be critically discussed.}, language = {de} } @article{KoenigReschkeWolteretal.2013, author = {K{\"o}nig, Niklas and Reschke, Antje and Wolter, Martin and M{\"u}ller, Steffen and Mayer, Frank and Baur, Heiner}, title = {Plantar pressure trigger for reliable nerve stimulus application during dynamic H-reflex measurements}, series = {Gait \& posture}, volume = {37}, journal = {Gait \& posture}, number = {4}, publisher = {Elsevier}, address = {Clare}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2012.09.021}, pages = {637 -- 639}, year = {2013}, abstract = {In dynamic H-reflex measurements, the standardisation of the nerve stimulation to the gait cycle is crucial to avoid misinterpretation due to altered pre-synaptic inhibition. In this pilot study, a plantar pressure sole was used to trigger the stimulation of the tibialis nerve with respect to the gait cycle. Consequently, the intersession reliability of the soleus muscle H-reflex during treadmill walking was investigated. Seven young participants performed walking trials on a treadmill at 5 km/h. The stimulating electrode was placed on the tibial nerve in the popliteal fossa. An EMG was recorded from the soleus muscle. To synchronize the stimulus to the gait cycle, initial heel strike was detected with a plantar pressure sole. Maximum H-reflex amplitude and M-wave amplitude were obtained and the Hmax/Mmax ratio was calculated. Data reveals excellent reliability, ICC = 0.89. Test-retest variability was 13.0\% (+/- 11.8). The Bland-Altman analysis showed a systematic error of 2.4\%. The plantar pressure sole was capable of triggering the stimulation of the tibialis nerve in a reliable way and offers a simple technique for the evaluation of reflex activity during walking.}, language = {en} } @article{CasselIntziegianniRischetal.2017, author = {Cassel, Michael and Intziegianni, Konstantina and Risch, Lucie and Mueller, Steffen and Engel, Tilman and Mayer, Frank}, title = {Physiological Tendon Thickness Adaptation in Adolescent Elite Athletes: A Longitudinal Study}, series = {Frontiers in physiology}, volume = {8}, journal = {Frontiers in physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2017.00795}, pages = {599 -- 611}, year = {2017}, abstract = {Increased Achilles (AT) and Patellar tendon (PT) thickness in adolescent athletes compared to non-athletes could be shown. However, it is unclear, if changes are of pathological or physiological origin due to training. The aim of this study was to determine physiological AT and PT thickness adaptation in adolescent elite athletes compared to non-athletes, considering sex and sport. In a longitudinal study design with two measurement days (M1/M2) within an interval of 3.2 +/- 0.8 years, 131 healthy adolescent elite athletes (m/f: 90/41) out of 13 different sports and 24 recreationally active controls (m/f: 6/18) were included. Both ATs and PTs were measured at standardized reference points. Athletes were divided into 4 sport categories [ball (B), combat (C), endurance (E) and explosive strength sports (S)]. Descriptive analysis (mean SD) and statistical testing for group differences was performed (cy = 0.05). AT thickness did not differ significantly between measurement days, neither in athletes (5.6 +/- 0.7 mm/5.6 +/- 0.7 mm) nor in controls (4.8 +/- 0.4 mm/4.9 +/- 0.5 mm, p > 0.05). For PTs, athletes presented increased thickness at M2 (Ml: 3.5 +/- 0.5 mm, M2: 3.8 +/- 0.5 mm, p < 0.001). In general, males had thicker ATs and PTs than females (p < 0.05). Considering sex and sports, only male athletes from B, C, and S showed significant higher PT-thickness at M2 compared to controls (p <= 0.01). Sport-specific adaptation regarding tendon thickness in adolescent elite athletes can be detected in PTs among male athletes participating in certain sports with high repetitive jumping and strength components. Sonographic microstructural analysis might provide an enhanced insight into tendon material properties enabling the differentiation of sex and influence of different sports.}, language = {en} } @misc{CasselIntziegianniRischetal.2017, author = {Cassel, Michael and Intziegianni, Konstantina and Risch, Lucie and M{\"u}ller, Steffen and Engel, Tilman and Mayer, Frank}, title = {Physiological Tendon Thickness Adaptation in Adolescent Elite Athletes}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-403823}, pages = {8}, year = {2017}, abstract = {Increased Achilles (AT) and Patellar tendon (PT) thickness in adolescent athletes compared to non-athletes could be shown. However, it is unclear, if changes are of pathological or physiological origin due to training. The aim of this study was to determine physiological AT and PT thickness adaptation in adolescent elite athletes compared to non-athletes, considering sex and sport. In a longitudinal study design with two measurement days (M1/M2) within an interval of 3.2 ± 0.8 years, 131 healthy adolescent elite athletes (m/f: 90/41) out of 13 different sports and 24 recreationally active controls (m/f: 6/18) were included. Both ATs and PTs were measured at standardized reference points. Athletes were divided into 4 sport categories [ball (B), combat (C), endurance (E) and explosive strength sports (S)]. Descriptive analysis (mean ± SD) and statistical testing for group differences was performed (α = 0.05). AT thickness did not differ significantly between measurement days, neither in athletes (5.6 ± 0.7 mm/5.6 ± 0.7 mm) nor in controls (4.8 ± 0.4 mm/4.9 ± 0.5 mm, p > 0.05). For PTs, athletes presented increased thickness at M2 (M1: 3.5 ± 0.5 mm, M2: 3.8 ± 0.5 mm, p < 0.001). In general, males had thicker ATs and PTs than females (p < 0.05). Considering sex and sports, only male athletes from B, C, and S showed significant higher PT-thickness at M2 compared to controls (p ≤ 0.01). Sport-specific adaptation regarding tendon thickness in adolescent elite athletes can be detected in PTs among male athletes participating in certain sports with high repetitive jumping and strength components. Sonographic microstructural analysis might provide an enhanced insight into tendon material properties enabling the differentiation of sex and influence of different sports.}, language = {en} } @article{CasselIntziegianniRischetal.2017, author = {Cassel, Michael and Intziegianni, Konstantina and Risch, Lucie and M{\"u}ller, Steffen and Engel, Tilman and Mayer, Frank}, title = {Physiological Tendon Thickness Adaptation in Adolescent Elite Athletes}, series = {Frontiers in physiology}, volume = {8}, journal = {Frontiers in physiology}, publisher = {Frontiers}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2017.00795}, pages = {1 -- 8}, year = {2017}, abstract = {Increased Achilles (AT) and Patellar tendon (PT) thickness in adolescent athletes compared to non-athletes could be shown. However, it is unclear, if changes are of pathological or physiological origin due to training. The aim of this study was to determine physiological AT and PT thickness adaptation in adolescent elite athletes compared to non-athletes, considering sex and sport. In a longitudinal study design with two measurement days (M1/M2) within an interval of 3.2 ± 0.8 years, 131 healthy adolescent elite athletes (m/f: 90/41) out of 13 different sports and 24 recreationally active controls (m/f: 6/18) were included. Both ATs and PTs were measured at standardized reference points. Athletes were divided into 4 sport categories [ball (B), combat (C), endurance (E) and explosive strength sports (S)]. Descriptive analysis (mean ± SD) and statistical testing for group differences was performed (α = 0.05). AT thickness did not differ significantly between measurement days, neither in athletes (5.6 ± 0.7 mm/5.6 ± 0.7 mm) nor in controls (4.8 ± 0.4 mm/4.9 ± 0.5 mm, p > 0.05). For PTs, athletes presented increased thickness at M2 (M1: 3.5 ± 0.5 mm, M2: 3.8 ± 0.5 mm, p < 0.001). In general, males had thicker ATs and PTs than females (p < 0.05). Considering sex and sports, only male athletes from B, C, and S showed significant higher PT-thickness at M2 compared to controls (p ≤ 0.01). Sport-specific adaptation regarding tendon thickness in adolescent elite athletes can be detected in PTs among male athletes participating in certain sports with high repetitive jumping and strength components. Sonographic microstructural analysis might provide an enhanced insight into tendon material properties enabling the differentiation of sex and influence of different sports.}, language = {en} } @inproceedings{ScharhagRosenbergerCarlsohnSchueleretal.2012, author = {Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Sch{\"u}ler, Stefan and Lundby, Carsten and Mayer, Frank and Scharhag, J{\"u}rgen}, title = {Physiological changes over four maximal incremental cycling tests within one day}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {933 -- 934}, year = {2012}, language = {en} } @article{CarlsohnRohnMayeretal.2010, author = {Carlsohn, Anja and Rohn, Sascha and Mayer, Frank and Schweigert, Florian J.}, title = {Physical activity, antioxidant status, and protein modification in adolescent athletes}, issn = {0195-9131}, doi = {10.1249/Mss.0b013e3181c74f7b}, year = {2010}, abstract = {Exercise may increase reactive oxygen species production, which might impair cell integrity and contractile function of muscle cells. However, little is known about the effect of regular exercise on the antioxidant status of adolescents. Purpose: This study aimed to evaluate the impact of exercise on the antioxidant status and protein modifications in adolescent athletes. Methods: In 90 athletes and 18 controls (16 +/- 2 yr), exercise-related energy expenditure was calculated on the basis of a 7-d activity protocol. Antioxidant intake and plasma concentrations of alpha-tocopherol, carotenoids, and uric acid were analyzed. Plasma antioxidant activity was determined by Trolox equivalent (TE) antioxidant capacity and electron spin resonance spectrometry. Protein modifications were assessed with structural changes of transthyretin using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Data were analyzed by two-way ANOVA and post hoc by the Tukey-Kramer test (alpha = 0.05). Results: Antioxidant intake correlated with energy intake and was within the recommended daily allowance for vitamins C and E and beta-carotene. Plasma levels of neither nutritional antioxidants nor uric acid differed between the groups. TE antioxidant capacity was higher in athletes (men = 1.47 perpendicular to 0.2 mmol TE per liter, women = 1.45 perpendicular to 0.2 mmol TE per liter) compared with controls (men = 1.17 +/- 0.04 mmol TE per liter, women = 1.14 +/- 0.04 mmol TE per liter) and increased with exercise-related energy expenditure (P = 0.007). Transthyretin cysteinylation rate differed between the groups, with the highest rate of protein modifications in moderately active subjects (P = 0.007). Conclusions: Results suggest that if the nutritional choice of athletes is well balanced, enough antioxidants are provided to meet recommended amounts. Moreover, regular exercise increases blood antioxidant capacity in young athletes, whereas chronic exercise was not shown to promote protein modifications. Thus, in young athletes who are sufficiently supplied with antioxidants, beneficial effects of exercise on antioxidant status rather than on oxidative stress may be anticipated.}, language = {en} } @article{CarlsohnScharhagRosenbergerCasseletal.2011, author = {Carlsohn, Anja and Scharhag-Rosenberger, Friederike and Cassel, Michael and Weber, Josefine and Guzman, Annette de Guzman and Mayer, Frank}, title = {Physical activity levels to estimate the energy requirement of adolescent athletes}, series = {Pediatric exercise science}, volume = {23}, journal = {Pediatric exercise science}, number = {2}, publisher = {Human Kinetics Publ.}, address = {Champaign}, issn = {0899-8493}, pages = {261 -- 269}, year = {2011}, abstract = {Adequate energy intake in adolescent athletes is considered important. Total energy expenditure (TEE) can be calculated from resting energy expenditure (REE) and physical activity level (PAL). However, validated PAL recommendations are available for adult athletes only. Purpose was to comprise physical activity data in adolescent athletes and to establish PAL recommendations for this population. In 64 competitive athletes (15.3 +/- 1.5yr, 20.5 +/- 2.0kg/m(2)) and 14 controls (15.1 +/- 1.1yr, 21 +/- 2.1kg/m(2)) TEE was calculated using 7-day activity protocols validated against doubly-labeled water. REE was estimated by Schofield-HW equation, and PAL was calculated as TEE:REE. Observed PAL in adolescent athletes (1.90 +/- 0.35) did not differ compared with controls (1.84 +/- 0.32, p = .582) and was lower than recommended for adult athletes by the WHO. In conclusion, applicability of PAL values recommended for adult athletes to estimate energy requirements in adolescent athletes must be questioned. Instead, a PAL range of 1.75-2.05 is suggested.}, language = {en} } @article{DiehlMayerMayeretal.2015, author = {Diehl, Katharina and Mayer, Manfred and Mayer, Frank and G{\"o}rig, Tatiana and Bock, Christina and Herr, Raphael M. and Schneider, Sven}, title = {Physical Activity Counseling by Primary Care Physicians: Attitudes, Knowledge, Implementation, and Perceived Success}, series = {Journal of physical activity and health}, volume = {12}, journal = {Journal of physical activity and health}, number = {2}, publisher = {Human Kinetics Publ.}, address = {Champaign}, issn = {1543-3080}, doi = {10.1123/jpah.2013-0273}, pages = {216 -- 223}, year = {2015}, abstract = {Background: In physical activity (PA) counseling, primary care physicians (PCPs) play a key role because they are in regular contact with large sections of the population and are important contact people in all health-related issues. However, little is known about their attitudes, knowledge, and perceived success, as well as about factors associated with the implementation of PA counseling. Methods: We collected data from 4074 PCPs including information on physician and practice characteristics, attitudes toward cardiovascular disease (CVD) prevention, and measures used during routine practice to prevent CVD. Here, we followed widely the established 5 A's strategy (Assess, Advise, Agree, Assist, Arrange). Results: The majority (87.2\%) of PCPs rated their own level of competence in PA counseling as 'high,' while 52.3\% rated their own capability to motivate patients to increase PA as 'not good.' Nine of ten PCPs routinely provided at least 1 measure of the modified 5 A's strategy, while 9.5\% routinely used all 5 intervention strategies. Conclusions: The positive attitude toward PA counseling among PCPs should be supported by other stakeholders in the field of prevention and health promotion. An example would be the reimbursement of health counseling services by compulsory health insurance, which would enable PCPs to invest more time in individualized health promotion.}, language = {en} } @misc{WippertPuschmannDriessleinetal.2020, author = {Wippert, Pia-Maria and Puschmann, Anne-Katrin and Drießlein, David and Banzer, Winfried and Beck, Heidrun and Schiltenwolf, Marcus and Schneider, Christian and Mayer, Frank}, title = {Personalized treatment suggestions}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {690}, issn = {1866-8364}, doi = {10.25932/publishup-47199}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-471993}, pages = {13}, year = {2020}, abstract = {Background: The back pain screening tool Risk-Prevention-Index Social (RPI-S) identifies the individual psychosocial risk for low back pain chronification and supports the allocation of patients at risk in additional multidisciplinary treatments. The study objectives were to evaluate (1) the prognostic validity of the RPI-S for a 6-month time frame and (2) the clinical benefit of the RPI-S. Methods: In a multicenter single-blind 3-armed randomized controlled trial, n = 660 persons (age 18-65 years) were randomly assigned to a twelve-week uni- or multidisciplinary exercise intervention or control group. Psychosocial risk was assessed by the RPI-S domain social environment (RPI-SSE) and the outcome pain by the Chronic Pain Grade Questionnaire (baseline M1, 12-weeks M4, 24-weeks M5). Prognostic validity was quantified by the root mean squared error (RMSE) within the control group. The clinical benefit of RPI-SSE was calculated by repeated measures ANOVA in intervention groups. Results: A subsample of n = 274 participants (mean = 38.0 years, SD 13.1) was analyzed, of which 30\% were classified at risk in their psychosocial profile. The half-year prognostic validity was good (RMSE for disability of 9.04 at M4 and of 9.73 at M5; RMSE for pain intensity of 12.45 at M4 and of 14.49 at M5). People at risk showed significantly stronger reduction in pain disability and intensity at M4/M5, if participating in a multidisciplinary exercise treatment. Subjects at no risk showed a smaller reduction in pain disability in both interventions and no group differences for pain intensity. Regarding disability due to pain, around 41\% of the sample would gain an unfitted treatment without the back pain screening. Conclusion: The RPI-SSE prognostic validity demonstrated good applicability and a clinical benefit confirmed by a clear advantage of an individualized treatment possibility.}, language = {en} } @article{CasselStollSchugardtetal.2019, author = {Cassel, Michael and Stoll, Josefine and Schugardt, Monique and Mayer, Frank}, title = {Overuse and injury prevention}, series = {Elite youth cycling}, journal = {Elite youth cycling}, publisher = {Routledge}, address = {London}, isbn = {978-1-315-11077-6}, pages = {141 -- 159}, year = {2019}, language = {en} } @misc{CasselMuellerMoseretal.2019, author = {Cassel, Michael and M{\"u}ller, Juliane and Moser, Othmar and Strempler, Mares Elaine and Reso, Judith and Mayer, Frank}, title = {Orthopedic Injury Profiles in Adolescent Elite Athletes}, series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, number = {559}, issn = {1866-8364}, doi = {10.25932/publishup-43495}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-434953}, pages = {10}, year = {2019}, abstract = {Aim: The aim of the study was to identify common orthopedic sports injury profiles in adolescent elite athletes with respect to age, sex, and anthropometrics. Methods: A retrospective data analysis of 718 orthopedic presentations among 381 adolescent elite athletes from 16 different sports to a sports medical department was performed. Recorded data of history and clinical examination included area, cause and structure of acute and overuse injuries. Injury-events were analyzed in the whole cohort and stratified by age (11-14/15-17 years) and sex. Group differences were tested by chi-squared-tests. Logistic regression analysis was applied examining the influence of factors age, sex, and body mass index (BMI) on the outcome variables area and structure (a = 0.05). Results: Higher proportions of injury-events were reported for females (60\%) and athletes of the older age group (66\%) than males and younger athletes. The most frequently injured area was the lower extremity (47\%) followed by the spine (30.5\%) and the upper extremity (12.5\%). Acute injuries were mainly located at the lower extremity (74.5\%), while overuse injuries were predominantly observed at the lower extremity (41\%) as well as the spine (36.5\%). Joints (34\%), muscles (22\%), and tendons (21.5\%) were found to be the most often affected structures. The injured structures were different between the age groups (p = 0.022), with the older age group presenting three times more frequent with ligament pathology events (5.5\%/2\%) and less frequent with bony problems (11\%/20.5\%) than athletes of the younger age group. The injured area differed between the sexes (p = 0.005), with males having fewer spine injury-events (25.5\%/34\%) but more upper extremity injuries (18\%/9\%) than females. Regression analysis showed statistically significant influence for BMI (p = 0.002) and age (p = 0.015) on structure, whereas the area was significantly influenced by sex (p = 0.005). Conclusion: Events of soft-tissue overuse injuries are the most common reasons resulting in orthopedic presentations of adolescent elite athletes. Mostly, the lower extremity and the spine are affected, while sex and age characteristics on affected area and structure must be considered. Therefore, prevention strategies addressing the injury-event profiles should already be implemented in early adolescence taking age, sex as well as injury entity into account.}, language = {en} } @article{CasselMuellerMoseretal.2019, author = {Cassel, Michael and M{\"u}ller, Juliane and Moser, Othmar and Strempler, Mares Elaine and Reso, Judith and Mayer, Frank}, title = {Orthopedic Injury Profiles in Adolescent Elite Athletes}, series = {Frontiers in Physiology}, volume = {10}, journal = {Frontiers in Physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2019.00544}, pages = {10}, year = {2019}, abstract = {Aim: The aim of the study was to identify common orthopedic sports injury profiles in adolescent elite athletes with respect to age, sex, and anthropometrics. Methods: A retrospective data analysis of 718 orthopedic presentations among 381 adolescent elite athletes from 16 different sports to a sports medical department was performed. Recorded data of history and clinical examination included area, cause and structure of acute and overuse injuries. Injury-events were analyzed in the whole cohort and stratified by age (11-14/15-17 years) and sex. Group differences were tested by chi-squared-tests. Logistic regression analysis was applied examining the influence of factors age, sex, and body mass index (BMI) on the outcome variables area and structure (a = 0.05). Results: Higher proportions of injury-events were reported for females (60\%) and athletes of the older age group (66\%) than males and younger athletes. The most frequently injured area was the lower extremity (47\%) followed by the spine (30.5\%) and the upper extremity (12.5\%). Acute injuries were mainly located at the lower extremity (74.5\%), while overuse injuries were predominantly observed at the lower extremity (41\%) as well as the spine (36.5\%). Joints (34\%), muscles (22\%), and tendons (21.5\%) were found to be the most often affected structures. The injured structures were different between the age groups (p = 0.022), with the older age group presenting three times more frequent with ligament pathology events (5.5\%/2\%) and less frequent with bony problems (11\%/20.5\%) than athletes of the younger age group. The injured area differed between the sexes (p = 0.005), with males having fewer spine injury-events (25.5\%/34\%) but more upper extremity injuries (18\%/9\%) than females. Regression analysis showed statistically significant influence for BMI (p = 0.002) and age (p = 0.015) on structure, whereas the area was significantly influenced by sex (p = 0.005). Conclusion: Events of soft-tissue overuse injuries are the most common reasons resulting in orthopedic presentations of adolescent elite athletes. Mostly, the lower extremity and the spine are affected, while sex and age characteristics on affected area and structure must be considered. Therefore, prevention strategies addressing the injury-event profiles should already be implemented in early adolescence taking age, sex as well as injury entity into account.}, language = {en} } @article{MuellerEngelKopinskietal.2017, author = {M{\"u}ller, Juliane and Engel, Tilman and Kopinski, Stephan and Mayer, Frank and M{\"u}ller, Steffen}, title = {Neuromuscular trunk activation patterns in back pain patients during one-handed lifting}, series = {World journal of orthopedics}, volume = {8}, journal = {World journal of orthopedics}, number = {2}, publisher = {Baishideng Publishing Group}, address = {Pleasanton}, issn = {2218-5836}, doi = {10.5312/wjo.v8.i2.142}, pages = {142 -- 148}, year = {2017}, abstract = {AIM To analyze neuromuscular activity patterns of the trunk in healthy controls (H) and back pain patients (BPP) during one-handed lifting of light to heavy loads. METHODS RESULTS Seven subjects (3m/4f; 32 +/- 7 years; 171 +/- 7 cm; 65 +/- 11 kg) were assigned to BPP (pain grade >= 2) and 36 (13m/23f; 28 +/- 8 years; 174 +/- 10 cm; 71 +/- 12 kg) to H (pain grade <= 1). H and BPP did not differ significantly in anthropometrics (P > 0.05). All subjects were able to lift the light and middle loads, but 57\% of BPP and 22\% of H were not able to lift the heavy load (all women) chi(2) analysis revealed statistically significant differences in task failure between H vs BPP (P = 0.03). EMG-RMS ranged from 33\% +/- 10\%/30\% +/- 9\% (DL, 1 kg) to 356\% +/- 148\%/283\% +/- 80\% (VR, 20 kg) in H/BPP with no statistical difference between groups regardless of load (P > 0.05). However, the EMG-RMS of the VR was greatest in all lifting tasks for both groups and increased with heavier loads. CONCLUSION Heavier loading leads to an increase (2-to 3-fold) in trunk muscle activity with comparable patterns. Heavy loading (20 kg) leads to task failure, especially in women with back pain.}, language = {en} } @unpublished{Mayer2014, author = {Mayer, Frank}, title = {Neuromuscular training reduces cruciate ligament ruptures}, series = {Der Orthop{\"a}de}, volume = {43}, journal = {Der Orthop{\"a}de}, number = {9}, publisher = {Springer}, address = {New York}, issn = {0085-4530}, pages = {858 -- 858}, year = {2014}, language = {de} } @article{BaritelloKhajooeiEngeletal.2020, author = {Baritello, Omar and Khajooei, Mina and Engel, Tilman and Kopinski, Stephan and Quarmby, Andrew James and M{\"u}ller, Steffen and Mayer, Frank}, title = {Neuromuscular shoulder activity during exercises with different combinations of stable and unstable weight mass}, series = {BMC sports science, medicine and rehabilitation}, volume = {12}, journal = {BMC sports science, medicine and rehabilitation}, number = {1}, publisher = {BioMed Central}, address = {London}, issn = {2052-1847}, doi = {10.1186/s13102-020-00168-x}, pages = {14}, year = {2020}, abstract = {Background Recent shoulder injury prevention programs have utilized resistance exercises combined with different forms of instability, with the goal of eliciting functional adaptations and thereby reducing the risk of injury. However, it is still unknown how an unstable weight mass (UWM) affects the muscular activity of the shoulder stabilizers. Aim of the study was to assess neuromuscular activity of dynamic shoulder stabilizers under four conditions of stable and UWM during three shoulder exercises. It was hypothesized that a combined condition of weight with UWM would elicit greater activation due to the increased stabilization demand. Methods Sixteen participants (7 m/9 f) were included in this cross-sectional study and prepared with an EMG-setup for the: Mm. upper/lower trapezius (U.TA/L.TA), lateral deltoid (DE), latissimus dorsi (LD), serratus anterior (SA) and pectoralis major (PE). A maximal voluntary isometric contraction test (MVIC; 5 s.) was performed on an isokinetic dynamometer. Next, internal/external rotation (In/Ex), abduction/adduction (Ab/Ad) and diagonal flexion/extension (F/E) exercises (5 reps.) were performed with four custom-made-pipes representing different exercise conditions. First, the empty-pipe (P; 0.5 kg) and then, randomly ordered, water-filled-pipe (PW; 1 kg), weight-pipe (PG; 4.5 kg) and weight + water-filled-pipe (PWG; 4.5 kg), while EMG was recorded. Raw root-mean-square values (RMS) were normalized to MVIC (\%MVIC). Differences between conditions for RMS\%MVIC, scapular stabilizer (SR: U.TA/L.TA; U.TA/SA) and contraction (CR: concentric/eccentric) ratios were analyzed (paired t-test; p <= 0.05; Bonferroni adjusted alpha = 0.008). Results PWG showed significantly greater muscle activity for all exercises and all muscles except for PE compared to P and PW. Condition PG elicited muscular activity comparable to PWG (p > 0.008) with significantly lower activation of L.TA and SA in the In/Ex rotation. The SR ratio was significantly higher in PWG compared to P and PW. No significant differences were found for the CR ratio in all exercises and for all muscles. Conclusion Higher weight generated greater muscle activation whereas an UWM raised the neuromuscular activity, increasing the stabilization demands. Especially in the In/Ex rotation, an UWM increased the RMS\%MVIC and SR ratio. This might improve training effects in shoulder prevention and rehabilitation programs.}, language = {en} } @misc{BaritelloKhajooeiEngeletal.2020, author = {Baritello, Omar and Khajooei, Mina and Engel, Tilman and Kopinski, Stephan and Quarmby, Andrew James and M{\"u}ller, Steffen and Mayer, Frank}, title = {Neuromuscular shoulder activity during exercises with different combinations of stable and unstable weight mass}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {1}, issn = {1866-8364}, doi = {10.25932/publishup-50936}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-509366}, pages = {16}, year = {2020}, abstract = {Background Recent shoulder injury prevention programs have utilized resistance exercises combined with different forms of instability, with the goal of eliciting functional adaptations and thereby reducing the risk of injury. However, it is still unknown how an unstable weight mass (UWM) affects the muscular activity of the shoulder stabilizers. Aim of the study was to assess neuromuscular activity of dynamic shoulder stabilizers under four conditions of stable and UWM during three shoulder exercises. It was hypothesized that a combined condition of weight with UWM would elicit greater activation due to the increased stabilization demand. Methods Sixteen participants (7 m/9 f) were included in this cross-sectional study and prepared with an EMG-setup for the: Mm. upper/lower trapezius (U.TA/L.TA), lateral deltoid (DE), latissimus dorsi (LD), serratus anterior (SA) and pectoralis major (PE). A maximal voluntary isometric contraction test (MVIC; 5 s.) was performed on an isokinetic dynamometer. Next, internal/external rotation (In/Ex), abduction/adduction (Ab/Ad) and diagonal flexion/extension (F/E) exercises (5 reps.) were performed with four custom-made-pipes representing different exercise conditions. First, the empty-pipe (P; 0.5 kg) and then, randomly ordered, water-filled-pipe (PW; 1 kg), weight-pipe (PG; 4.5 kg) and weight + water-filled-pipe (PWG; 4.5 kg), while EMG was recorded. Raw root-mean-square values (RMS) were normalized to MVIC (\%MVIC). Differences between conditions for RMS\%MVIC, scapular stabilizer (SR: U.TA/L.TA; U.TA/SA) and contraction (CR: concentric/eccentric) ratios were analyzed (paired t-test; p <= 0.05; Bonferroni adjusted alpha = 0.008). Results PWG showed significantly greater muscle activity for all exercises and all muscles except for PE compared to P and PW. Condition PG elicited muscular activity comparable to PWG (p > 0.008) with significantly lower activation of L.TA and SA in the In/Ex rotation. The SR ratio was significantly higher in PWG compared to P and PW. No significant differences were found for the CR ratio in all exercises and for all muscles. Conclusion Higher weight generated greater muscle activation whereas an UWM raised the neuromuscular activity, increasing the stabilization demands. Especially in the In/Ex rotation, an UWM increased the RMS\%MVIC and SR ratio. This might improve training effects in shoulder prevention and rehabilitation programs.}, language = {en} } @article{MuellerEngelMuelleretal.2016, author = {Mueller, Juliane and Engel, Tilman and Mueller, Steffen and Kopinski, Stephan and Baur, Heiner and Mayer, Frank}, title = {Neuromuscular response of the trunk to sudden gait disturbances: Forward vs. backward perturbation}, series = {Journal of electromyography and kinesiology}, volume = {30}, journal = {Journal of electromyography and kinesiology}, publisher = {Elsevier}, address = {Oxford}, issn = {1050-6411}, doi = {10.1016/j.jelekin.2016.07.005}, pages = {168 -- 176}, year = {2016}, abstract = {The study aimed to analyse neuromuscular activity of the trunk comparing four different perturbations during gait. Thirteen subjects (28 +/- 3 yrs) walked (1 m/s) on a split-belt treadmill, while 4 (belt) perturbations (F1, F2, B1, B2) were randomly applied. Perturbations differed, related to treadmill belt translation, in direction (forward (F)/backward (B)) and amplitude (20 m/s(2) (1)/40 m/s(2) (2)). Trunk muscle activity was assessed with a 12-lead-EMG. EMG-RMS [\%] (0-200 ms after perturbation; normalized to RMS of normal gait) was analyzed for muscles and four trunk areas (ventral left/right; dorsal left/right). Ratio of ventral: dorsal muscles were calculated. Muscle onset [ms] was determined. Data analysis was conducted descriptively, followed by ANOVA (post hoc Tukey-Kramer (alpha = 0.05)). All perturbations lead to an increase in EMG-RMS (428 +/- 289\%). F1 showed the lowest and F2 the highest increase for the flexors. B2 showed the highest increase for the extensors. Significant differences between perturbations could be observed for 6 muscles, as well as the 4 trunk areas. Ratio analysis revealed no significant differences (range 1.25 (B1) to 1.71 (F2) between stimuli. Muscle response time (ventral: 87.0 +/- 21.7 ms; dorsal: 88.4 +/- 17.0 ms) between stimuli was only significant (p = 0.005) for the dorsal muscles. Magnitude significantly influences neuromuscular trunk response patterns in healthy adults. Regardless of direction ventral muscles always revealed higher relative increase of activity while compensating the walking perturbations. (C) 2016 Elsevier Ltd. All rights reserved.}, language = {en} } @article{BaurHirschmuellerMuelleretal.2011, author = {Baur, Heiner and Hirschm{\"u}ller, Anja and M{\"u}ller, Steffen and Mayer, Frank}, title = {Neuromuscular activity of the peroneal muscle after foot orthoses therapy in runners}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {43}, journal = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {8}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, doi = {10.1249/MSS.0b013e31820c64ae}, pages = {1500 -- 1506}, year = {2011}, abstract = {BAUR, H., A. HIRSCHMULLER, S. MULLER, and F. MAYER. Neuromuscular Activity of the Peroneal Muscle after Foot Orthoses Therapy in Runners. Med. Sci. Sports Exerc., Vol. 43, No. 8, pp. 1500-1506, 2011. Purpose: Foot orthoses are a standard option to treat overuse injury. Biomechanical data providing mechanisms of foot orthoses' effectiveness are sparse. Stability of the ankle joint complex might be a key factor. The purpose was therefore to analyze neuromuscular activity of the musculus peroneus longus in runners with overuse injury symptoms treated with foot orthoses. Methods: A total of 99 male and female runners with overuse injury symptoms randomized in a control group (CO) and an orthoses group (OR) were analyzed on a treadmill at 3.3 m.s(-1) before and after an 8-wk foot orthoses intervention. Muscular activity of the musculus peroneus longus was measured and quantified in the time domain (initial onset of activation (T-ini), time of maximal activity (T-max), total time of activation (T-tot)) and amplitude domain (amplitude in preactivation (A(pre)), weight acceptance (A(wa)), push-off (A(po))). Results: Peroneal activity in the time domain did not differ initially between CO and OR, and no effect was observed after therapy (T-ini: CO = -0.88 +/- 0.09, OR = -0.88 +/- 0.08 / T-max: CO = 0.14 +/- 0.06, OR = 0.15 +/- 0.06 / T-tot: CO = 0.40 +/- 0.09, OR = 0.41 +/- 0.09; P > 0.05). In preactivation (Apre), muscle activity was higher in OR after intervention (CO = 0.97 +/- 0.32, 95\% confidence interval = 0.90-1.05; OR = 1.18 +/- 0.43, 95\% confidence interval = 1.08-1.28; P = 0.003). There was no group or intervention effect during stance (A(wa): CO = 2.33 +/- 0.66, OR = 2.33 +/- 0.74 / A(po): CO = 0.80 +/- 0.41, OR = 0.88 +/- 0.40; P > 0.05). Conclusions: Enhanced muscle activation of the musculus peroneus longus in preactivation suggests an altered preprogrammed activity, which might lead to better ankle stability providing a possible mode of action for foot orthoses therapy.}, language = {en} } @article{WochatzRabeWolteretal.2017, author = {Wochatz, Monique and Rabe, Sophie and Wolter, Martin and Engel, Tilman and Mueller, Steffen and Mayer, Frank}, title = {Muscle activity of upper and lower trapezius and serratus anterior during unloaded and maximal loaded shoulder flexion and extension}, series = {International Biomechanics}, volume = {4}, journal = {International Biomechanics}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, doi = {https://doi.org/10.1080/23335432.2017.1364668}, pages = {68 -- 76}, year = {2017}, abstract = {Altered scapular muscle activity is mostly described under unloaded and submaximal loaded conditions in impingement patients. However, there is no clear evidence on muscle activity with respect to movement phases under maximum load in healthy subjects. Therefore, this study aimed to investigate scapular muscle activity under unloaded and maximum loaded isokinetic shoulder flexion and extension in regard to the movement phase. Fourteen adults performed unloaded (continuous passive motion [CPM]) as well as maximum loaded (concentric [CON], eccentric [ECC]) isokinetic shoulder flexion (Flex) and extension (Ext). Simultaneously, scapular muscle activity was measured by EMG. Root mean square was calculated for the whole ROM and four movement phases. Data were analyzed descriptively and by two-way repeated measures ANOVA. CPMFlex resulted in a linear increase of muscle activity for all muscles. Muscle activity during CONFlex and ECCFlex resulted in either constant activity levels or in an initial increase followed by a plateau in the second half of movement. CPMExt decreased with the progression of movement, whereas CONExt and ECCExt initially decreased and either levelled off or increased in the second half of movement. Scapular muscle activity of unloaded shoulder flexion and extension changed under maximum load showing increased activity levels and an altered pattern over the course of movement.}, language = {en} } @article{KhajooeiLinMayeretal.2019, author = {Khajooei, Mina and Lin, Chiao-I and Mayer, Frank and Mueller, Steffen}, title = {Muscle activity and strength in maximum isokinetic legpress testing with unstable footplates in active individuals}, series = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, volume = {27}, journal = {Isokinetics and exercise science : official journal of the European Isokinetic Society}, number = {3}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0959-3020}, doi = {10.3233/IES-182206}, pages = {177 -- 183}, year = {2019}, abstract = {BACKGROUND: Compensating unstable situations is an important functional capability to maintain joint stability, to compensate perturbations and to prevent (re-)injury. Therefore, reduced maximum strength and altered neuromuscular activity are expected by inducing instability to load test situations. Possible effects are not clear for induced instability during maximum legpress tests in healthy individuals. OBJECTIVE: To compare isokinetic legpress (LP) strength and lower-leg muscle activity using stable (S) and unstable (UN) footplates. METHODS: 16 males (28 +/- 4 yrs, 179 +/- 7 cm, 75 +/- 8 kg) performed five maximum LP in concentric (CON) and eccentric (ECC) mode. The maximum force (Fmax) and muscle activity were measured under conditions of S and UN footplates. The tested muscles comprised of the tibialis anterior (TA), peroneus longus (PL) and soleus (SOL) and their activity were quantified against the MVIC of each muscle respectively. RESULTS: The main finding revealed a significant reduction in Fmax under UN condition: 11.9 +/- 11.3\% in CON and 23.5 +/- 47.8\% in ECC (P < 0.05). Significant findings were also noted regarding the RMS derived values of the EMG of PL and TA. CONCLUSION: Unstable LP reduced force generation and increased the activity of PL and TA muscles which confirmed greater neuromuscular effort to compensate instability. This may have some implications for resistance testing and training coupled with an unstable base in the prevention and rehabilitation of injury to the neuromusculoskeletal system.}, language = {en} } @article{LaineMartinezValdesFallaetal.2015, author = {Laine, Christopher M. and Martinez-Valdes, Eduardo Andr{\´e}s and Falla, Deborah and Mayer, Frank and Farina, Dario}, title = {Motor Neuron Pools of Synergistic Thigh Muscles Share Most of Their Synaptic Input}, series = {The journal of neuroscience}, volume = {35}, journal = {The journal of neuroscience}, number = {35}, publisher = {Society for Neuroscience}, address = {Washington}, issn = {0270-6474}, doi = {10.1523/JNEUROSCI.0240-15.2015}, pages = {12207 -- 12216}, year = {2015}, abstract = {Neural control of synergist muscles is not well understood. Presumably, each muscle in a synergistic group receives some unique neural drive and some drive that is also shared in common with other muscles in the group. In this investigation, we sought to characterize the strength, frequency spectrum, and force dependence of the neural drive to the human vastus lateralis and vastus medialis muscles during the production of isometric knee extension forces at 10 and 30\% of maximum voluntary effort. High-density surface electromyography recordings were decomposed into motor unit action potentials to examine the neural drive to each muscle. Motor unit coherence analysis was used to characterize the total neural drive to each muscle and the drive shared between muscles. Using a novel approach based on partial coherence analysis, we were also able to study specifically the neural drive unique to each muscle (not shared). The results showed that the majority of neural drive to the vasti muscles was a cross-muscle drive characterized by a force-dependent strength and bandwidth. Muscle-specific neural drive was at low frequencies (<5 Hz) and relatively weak. Frequencies of neural drive associated with afferent feedback (6 - 12 Hz) and with descending cortical input (similar to 20 Hz) were almost entirely shared by the two muscles, whereas low-frequency (<5 Hz) drive comprised shared (primary) and muscle-specific (secondary) components. This study is the first to directly investigate the extent of shared versus independent control of synergist muscles at the motor neuron level.}, language = {en} } @misc{SchraplauBlockHaeusleretal.2021, author = {Schraplau, Anne and Block, Andrea and H{\"a}usler, Andreas and Wippert, Pia-Maria and Rapp, Michael A. and V{\"o}ller, Heinz and Bonaventura, Klaus and Mayer, Frank}, title = {Mobile diagnostics and consultation for the prevention of the metabolic syndrome and its secondary diseases in Brandenburg—study protocol of a regional prospective cohort study: the Mobile Brandenburg Cohort}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1866-8364}, doi = {10.25932/publishup-54950}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-549506}, pages = {1 -- 11}, year = {2021}, abstract = {Background The metabolic syndrome (MetS) is a risk cluster for a number of secondary diseases. The implementation of prevention programs requires early detection of individuals at risk. However, access to health care providers is limited in structurally weak regions. Brandenburg, a rural federal state in Germany, has an especially high MetS prevalence and disease burden. This study aims to validate and test the feasibility of a setup for mobile diagnostics of MetS and its secondary diseases, to evaluate the MetS prevalence and its association with moderating factors in Brandenburg and to identify new ways of early prevention, while establishing a "Mobile Brandenburg Cohort" to reveal new causes and risk factors for MetS. Methods In a pilot study, setups for mobile diagnostics of MetS and secondary diseases will be developed and validated. A van will be equipped as an examination room using point-of-care blood analyzers and by mobilizing standard methods. In study part A, these mobile diagnostic units will be placed at different locations in Brandenburg to locally recruit 5000 participants aged 40-70 years. They will be examined for MetS and advice on nutrition and physical activity will be provided. Questionnaires will be used to evaluate sociodemographics, stress perception, and physical activity. In study part B, participants with MetS, but without known secondary diseases, will receive a detailed mobile medical examination, including MetS diagnostics, medical history, clinical examinations, and instrumental diagnostics for internal, cardiovascular, musculoskeletal, and cognitive disorders. Participants will receive advice on nutrition and an exercise program will be demonstrated on site. People unable to participate in these mobile examinations will be interviewed by telephone. If necessary, participants will be referred to general practitioners for further diagnosis. Discussion The mobile diagnostics approach enables early detection of individuals at risk, and their targeted referral to local health care providers. Evaluation of the MetS prevalence, its relation to risk-increasing factors, and the "Mobile Brandenburg Cohort" create a unique database for further longitudinal studies on the implementation of home-based prevention programs to reduce mortality, especially in rural regions. Trial registration German Clinical Trials Register, DRKS00022764; registered 07 October 2020—retrospectively registered.}, language = {en} } @article{SchraplauBlockHaeusleretal.2021, author = {Schraplau, Anne and Block, Andrea and H{\"a}usler, Andreas and Wippert, Pia-Maria and Rapp, Michael A. and V{\"o}ller, Heinz and Bonaventura, Klaus and Mayer, Frank}, title = {Mobile diagnostics and consultation for the prevention of the metabolic syndrome and its secondary diseases in Brandenburg—study protocol of a regional prospective cohort study}, series = {Pilot and Feasibility Studies}, volume = {7}, journal = {Pilot and Feasibility Studies}, publisher = {BioMed Central (Springer Nature)}, address = {London}, issn = {2055-5784}, doi = {10.1186/s40814-021-00898-w}, pages = {1 -- 11}, year = {2021}, abstract = {Background The metabolic syndrome (MetS) is a risk cluster for a number of secondary diseases. The implementation of prevention programs requires early detection of individuals at risk. However, access to health care providers is limited in structurally weak regions. Brandenburg, a rural federal state in Germany, has an especially high MetS prevalence and disease burden. This study aims to validate and test the feasibility of a setup for mobile diagnostics of MetS and its secondary diseases, to evaluate the MetS prevalence and its association with moderating factors in Brandenburg and to identify new ways of early prevention, while establishing a "Mobile Brandenburg Cohort" to reveal new causes and risk factors for MetS. Methods In a pilot study, setups for mobile diagnostics of MetS and secondary diseases will be developed and validated. A van will be equipped as an examination room using point-of-care blood analyzers and by mobilizing standard methods. In study part A, these mobile diagnostic units will be placed at different locations in Brandenburg to locally recruit 5000 participants aged 40-70 years. They will be examined for MetS and advice on nutrition and physical activity will be provided. Questionnaires will be used to evaluate sociodemographics, stress perception, and physical activity. In study part B, participants with MetS, but without known secondary diseases, will receive a detailed mobile medical examination, including MetS diagnostics, medical history, clinical examinations, and instrumental diagnostics for internal, cardiovascular, musculoskeletal, and cognitive disorders. Participants will receive advice on nutrition and an exercise program will be demonstrated on site. People unable to participate in these mobile examinations will be interviewed by telephone. If necessary, participants will be referred to general practitioners for further diagnosis. Discussion The mobile diagnostics approach enables early detection of individuals at risk, and their targeted referral to local health care providers. Evaluation of the MetS prevalence, its relation to risk-increasing factors, and the "Mobile Brandenburg Cohort" create a unique database for further longitudinal studies on the implementation of home-based prevention programs to reduce mortality, especially in rural regions. Trial registration German Clinical Trials Register, DRKS00022764; registered 07 October 2020—retrospectively registered.}, language = {en} } @inproceedings{HeydenreichCarlsohnLinneetal.2012, author = {Heydenreich, Juliane and Carlsohn, Anja and Linne, Karsten and Mayer, Frank}, title = {Micronutrient intake in young athletes}, series = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, volume = {44}, booktitle = {Medicine and science in sports and exercise : official journal of the American College of Sports Medicine}, number = {1}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0195-9131}, pages = {951 -- 951}, year = {2012}, language = {en} } @article{NiedererVogtWippertetal.2016, author = {Niederer, Daniel and Vogt, Lutz and Wippert, Pia-Maria and Puschmann, Anne-Katrin and Pfeifer, Ann-Christin and Schiltenwolf, Marcus and Banzer, Winfried and Mayer, Frank}, title = {Medicine in spine exercise (MiSpEx) for nonspecific low back pain patients: study protocol for a multicentre, single-blind randomized controlled trial}, series = {Trials}, volume = {17}, journal = {Trials}, publisher = {BioMed Central}, address = {London}, issn = {1745-6215}, doi = {10.1186/s13063-016-1645-1}, pages = {9}, year = {2016}, abstract = {Background: Arising from the relevance of sensorimotor training in the therapy of nonspecific low back pain patients and from the value of individualized therapy, the present trial aims to test the feasibility and efficacy of individualized sensorimotor training interventions in patients suffering from nonspecific low back pain. Methods and study design: A multicentre, single-blind two-armed randomized controlled trial to evaluate the effects of a 12-week (3 weeks supervised centre-based and 9 weeks home-based) individualized sensorimotor exercise program is performed. The control group stays inactive during this period. Outcomes are pain, and pain-associated function as well as motor function in adults with nonspecific low back pain. Each participant is scheduled to five measurement dates: baseline (M1), following centre-based training (M2), following home-based training (M3) and at two follow-up time points 6 months (M4) and 12 months (M5) after M1. All investigations and the assessment of the primary and secondary outcomes are performed in a standardized order: questionnaires - clinical examination biomechanics (motor function). Subsequent statistical procedures are executed after the examination of underlying assumptions for parametric or rather non-parametric testing. Discussion: The results and practical relevance of the study will be of clinical and practical relevance not only for researchers and policy makers but also for the general population suffering from nonspecific low back pain.}, language = {en} } @misc{NiedererVogtWippertetal.2016, author = {Niederer, Daniel and Vogt, Lutz and Wippert, Pia-Maria and Puschmann, Anne-Katrin and Pfeifer, Ann-Christin and Schiltenwolf, Marcus and Banzer, Winfried and Mayer, Frank}, title = {Medicine in spine exercise (MiSpEx) for nonspecific low back pain patients}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {444}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-407308}, pages = {9}, year = {2016}, abstract = {Background: Arising from the relevance of sensorimotor training in the therapy of nonspecific low back pain patients and from the value of individualized therapy, the present trial aims to test the feasibility and efficacy of individualized sensorimotor training interventions in patients suffering from nonspecific low back pain. Methods and study design: A multicentre, single-blind two-armed randomized controlled trial to evaluate the effects of a 12-week (3 weeks supervised centre-based and 9 weeks home-based) individualized sensorimotor exercise program is performed. The control group stays inactive during this period. Outcomes are pain, and pain-associated function as well as motor function in adults with nonspecific low back pain. Each participant is scheduled to five measurement dates: baseline (M1), following centre-based training (M2), following home-based training (M3) and at two follow-up time points 6 months (M4) and 12 months (M5) after M1. All investigations and the assessment of the primary and secondary outcomes are performed in a standardized order: questionnaires - clinical examination - biomechanics (motor function). Subsequent statistical procedures are executed after the examination of underlying assumptions for parametric or rather non-parametric testing. Discussion: The results and practical relevance of the study will be of clinical and practical relevance not only for researchers and policy makers but also for the general population suffering from nonspecific low back pain. Trial registration: Identification number DRKS00010129. German Clinical Trial registered on 3 March 2016.}, language = {en} } @article{MayerBonaventuraCasseletal.2012, author = {Mayer, Frank and Bonaventura, Klaus and Cassel, Michael and M{\"u}ller, Steffen and Weber, Josefine and Scharhag-Rosenberger, Friederike and Carlsohn, Anja and Baur, Heiner and Scharhag, J{\"u}rgen}, title = {Medical results of preparticipation examination in adolescent athletes}, series = {British journal of sports medicine : the journal of sport and exercise medicine}, volume = {46}, journal = {British journal of sports medicine : the journal of sport and exercise medicine}, number = {7}, publisher = {BMJ Publ. Group}, address = {London}, issn = {0306-3674}, doi = {10.1136/bjsports-2011-090966}, pages = {524 -- 530}, year = {2012}, abstract = {Background Preparticipation examinations (PPE) are frequently used to evaluate eligibility for competitive sports in adolescent athletes. Nevertheless, the effectiveness of these examinations is under debate since costs are high and its validity is discussed controversial. Purpose To analyse medical findings and consequences in adolescent athletes prior to admission to a sports school. Methods In 733 adolescent athletes (318 girls, 415 boys, age 12.3+/-0.4, 16 sports disciplines), history and clinical examination (musculoskeletal, cardiovascular, general medicine) was performed to evaluate eligibility. PPE was completed by determination of blood parameters, ECG at rest and during ergometry, echocardiography and x-rays and ultrasonography if indicated. Eligibility was either approved or rated with restriction. Recommendations for therapy and/or prevention were given to the athletes and their parents. Results Historical (h) and clinical (c) findings (eg, pain, verified pathologies) were more frequent regarding the musculoskeletal system (h: 120, 16.4\%; c: 247, 33.7\%) compared to cardiovascular (h: 9, 1.2\%; c: 23, 3.1\%) or general medicine findings (h: 116, 15.8\%; c: 71, 9.7\%). ECG at rest was moderately abnormal in 46 (6.3\%) and severely abnormal in 25 athletes (3.4\%). Exercise ECG was suspicious in 25 athletes (3.4\%). Relevant echocardiographic abnormalities were found in 17 athletes (2.3\%). In 52 of 358 cases (14.5\%), x-rays led to diagnosis (eg, Spondylolisthesis). Eligibility was temporarily restricted in 41 athletes (5.6\%). Three athletes (0.4\%) had to be excluded from competitive sports. Therapy (eg, physiotherapy, medication) and/or prevention (sensorimotor training, vaccination) recommendations were deduced due to musculoskeletal (t:n = 76,10.3\%; p:n = 71,9.8\%) and general medicine findings (t:n = 80, 10.9\%; p:n = 104, 14.1\%). Conclusion Eligibility for competitive sports is restricted in only 5.5\% of adolescent athletes at age 12. Eligibility refusals are rare. However, recommendations for therapy and prevention are frequent, mainly regarding the musculoskeletal system. In spite of time and cost consumption, adolescent preparticipation before entering a career in high-performance sports is supported.}, language = {en} } @article{AppiahDwomohMuellerMayer2019, author = {Appiah-Dwomoh, Edem Korkor and M{\"u}ller, Steffen and Mayer, Frank}, title = {Is there an association between variables of static and dynamic postural control in adolescent athletes with back pain?}, series = {German Journal of Exercise and Sport Research}, volume = {49}, journal = {German Journal of Exercise and Sport Research}, number = {2}, publisher = {Springer}, address = {New York}, issn = {2509-3142}, doi = {10.1007/s12662-019-00573-6}, pages = {150 -- 155}, year = {2019}, abstract = {An association between static and dynamic postural control exists in adults with back pain. We aimed to determine whether this association also exists in adolescent athletes with the same condition. In all, 128 athletes with and without back pain performed three measurements of 15s of static (one-legged stance) and dynamic (star excursion balance test) postural control tests. All subjects and amatched subgroup of athletes with and without back pain were analyzed. The smallest center of pressure mediolateral and anterior-posterior displacements (mm) and normalized highest reach distance were the outcome measures. No association was found between variables of the static and dynamic tests for all subjects and the matched group with and without back pain. The control of static and dynamic posture in adolescent athletes with and without back pain might not be related.}, language = {en} }