@article{JafarnezhadgeroAnvariGranacher2020,
  author    = {Jafarnezhadgero, Amir Ali and Anvari, Maryam and Granacher, Urs},
  title     = {Long-term effects of shoe mileage on ground reaction forces and lower limb muscle activities during walking in individuals with genu varus},
  series = {Clinical biomechanics},
  volume    = {73},
  journal   = {Clinical biomechanics},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0268-0033},
  doi       = {10.1016/j.clinbiomech.2020.01.006},
  pages     = {55 -- 62},
  year      = {2020},
  abstract  = {Background: Shoe mileage is an important factor that may influence the risk of sustaining injuries during walking. The aims of this study were to examine the effects of shoe mileage on ground reaction forces and activity of lower limb muscles during walking in genu varus individuals compared with controls. Methods: Fifteen healthy and 15 genu varus females received a new pair of running shoes. They were asked to wear these shoes over 6 months. Pre and post intervention, mechanical shoe testing was conducted and ground reaction forces and muscle activities of the right leg were recorded during walking at preferred gait speed. Findings: Significant group-by-time interactions were found for shoe stiffness, antero-posterior and vertical impact peak. We observed higher shoe stiffness and lower impact peaks after intervention in both groups with larger effect sizes in genu varus. Significant group-by-time interactions were identified for vastus medialis (loading phase) and rectus femoris (loading and push-off). For vastus medialis, significant decreases were found from pre-to-post during the loading phase in the control group. Rectus femoris activity was higher post intervention during the loading and push-off phases in both groups with larger effect sizes in genu varus. Interpretation: Our findings indicate that the observed changes in ground reaction forces are more prominent in genu varus individuals. Together with our findings on shoe stiffness, it seems appropriate to change running shoes after an intense wearing time of 6 months, particularly in genu varus individuals.},
  language  = {en}
}
@article{JararnezhadgeroMamashliGranacher2021,
  author    = {Jararnezhadgero, AmirAli and Mamashli, Elaheh and Granacher, Urs},
  title     = {An Endurance-Dominated Exercise Program Improves Maximum Oxygen Consumption, Ground Reaction Forces, and Muscle Activities in Patients With Moderate Diabetic Neuropathy},
  series = {Frontiers in physiology / Frontiers Research Foundation},
  volume    = {12},
  journal   = {Frontiers in physiology / Frontiers Research Foundation},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne, Schweiz},
  issn      = {1664-042X},
  doi       = {10.3389/fphys.2021.654755},
  pages     = {1 -- 15},
  year      = {2021},
  abstract  = {Background: The prevalence of diabetes worldwide is predicted to increase from 2.8\% in 2000 to 4.4\% in 2030. Diabetic neuropathy (DN) is associated with damage to nerve glial cells, their axons, and endothelial cells leading to impaired function and mobility. Objective: We aimed to examine the effects of an endurance-dominated exercise program on maximum oxygen consumption (VO2max), ground reaction forces, and muscle activities during walking in patients with moderate DN. Methods: Sixty male and female individuals aged 45-65 years with DN were randomly assigned to an intervention (IG, n = 30) or a waiting control (CON, n = 30) group. The research protocol of this study was registered with the Local Clinical Trial Organization (IRCT20200201046326N1). IG conducted an endurance-dominated exercise program including exercises on a bike ergometer and gait therapy. The progressive intervention program lasted 12 weeks with three sessions per week, each 40-55 min. CON received the same treatment as IG after the post-tests. Pre- and post-training, VO2max was tested during a graded exercise test using spiroergometry. In addition, ground reaction forces and lower limbs muscle activities were recorded while walking at a constant speed of ∼1 m/s. Results: No statistically significant baseline between group differences was observed for all analyzed variables. Significant group-by-time interactions were found for VO2max (p < 0.001; d = 1.22). The post-hoc test revealed a significant increase in IG (p < 0.001; d = 1.88) but not CON. Significant group-by-time interactions were observed for peak lateral and vertical ground reaction forces during heel contact and peak vertical ground reaction force during push-off (p = 0.001-0.037; d = 0.56-1.53). For IG, post-hoc analyses showed decreases in peak lateral (p < 0.001; d = 1.33) and vertical (p = 0.004; d = 0.55) ground reaction forces during heel contact and increases in peak vertical ground reaction force during push-off (p < 0.001; d = 0.92). In terms of muscle activity, significant group-by-time interactions were found for vastus lateralis and gluteus medius during the loading phase and for vastus medialis during the mid-stance phase, and gastrocnemius medialis during the push-off phase (p = 0.001-0.044; d = 0.54-0.81). Post-hoc tests indicated significant intervention-related increases in vastus lateralis (p = 0.001; d = 1.08) and gluteus medius (p = 0.008; d = 0.67) during the loading phase and vastus medialis activity during mid-stance (p = 0.001; d = 0.86). In addition, post-hoc tests showed decreases in gastrocnemius medialis during the push-off phase in IG only (p < 0.001; d = 1.28). Conclusions: This study demonstrated that an endurance-dominated exercise program has the potential to improve VO2max and diabetes-related abnormal gait in patients with DN. The observed decreases in peak vertical ground reaction force during the heel contact of walking could be due to increased vastus lateralis and gluteus medius activities during the loading phase. Accordingly, we recommend to implement endurance-dominated exercise programs in type 2 diabetic patients because it is feasible, safe and effective by improving aerobic capacity and gait characteristics.},
  language  = {en}
}
@misc{JararnezhadgeroMamashliGranacher2021,
  author    = {Jararnezhadgero, AmirAli and Mamashli, Elaheh and Granacher, Urs},
  title     = {An Endurance-Dominated Exercise Program Improves Maximum Oxygen Consumption, Ground Reaction Forces, and Muscle Activities in Patients With Moderate Diabetic Neuropathy},
  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-54118},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-541182},
  pages     = {1 -- 15},
  year      = {2021},
  abstract  = {Background: The prevalence of diabetes worldwide is predicted to increase from 2.8\% in 2000 to 4.4\% in 2030. Diabetic neuropathy (DN) is associated with damage to nerve glial cells, their axons, and endothelial cells leading to impaired function and mobility. Objective: We aimed to examine the effects of an endurance-dominated exercise program on maximum oxygen consumption (VO2max), ground reaction forces, and muscle activities during walking in patients with moderate DN. Methods: Sixty male and female individuals aged 45-65 years with DN were randomly assigned to an intervention (IG, n = 30) or a waiting control (CON, n = 30) group. The research protocol of this study was registered with the Local Clinical Trial Organization (IRCT20200201046326N1). IG conducted an endurance-dominated exercise program including exercises on a bike ergometer and gait therapy. The progressive intervention program lasted 12 weeks with three sessions per week, each 40-55 min. CON received the same treatment as IG after the post-tests. Pre- and post-training, VO2max was tested during a graded exercise test using spiroergometry. In addition, ground reaction forces and lower limbs muscle activities were recorded while walking at a constant speed of ∼1 m/s. Results: No statistically significant baseline between group differences was observed for all analyzed variables. Significant group-by-time interactions were found for VO2max (p < 0.001; d = 1.22). The post-hoc test revealed a significant increase in IG (p < 0.001; d = 1.88) but not CON. Significant group-by-time interactions were observed for peak lateral and vertical ground reaction forces during heel contact and peak vertical ground reaction force during push-off (p = 0.001-0.037; d = 0.56-1.53). For IG, post-hoc analyses showed decreases in peak lateral (p < 0.001; d = 1.33) and vertical (p = 0.004; d = 0.55) ground reaction forces during heel contact and increases in peak vertical ground reaction force during push-off (p < 0.001; d = 0.92). In terms of muscle activity, significant group-by-time interactions were found for vastus lateralis and gluteus medius during the loading phase and for vastus medialis during the mid-stance phase, and gastrocnemius medialis during the push-off phase (p = 0.001-0.044; d = 0.54-0.81). Post-hoc tests indicated significant intervention-related increases in vastus lateralis (p = 0.001; d = 1.08) and gluteus medius (p = 0.008; d = 0.67) during the loading phase and vastus medialis activity during mid-stance (p = 0.001; d = 0.86). In addition, post-hoc tests showed decreases in gastrocnemius medialis during the push-off phase in IG only (p < 0.001; d = 1.28). Conclusions: This study demonstrated that an endurance-dominated exercise program has the potential to improve VO2max and diabetes-related abnormal gait in patients with DN. The observed decreases in peak vertical ground reaction force during the heel contact of walking could be due to increased vastus lateralis and gluteus medius activities during the loading phase. Accordingly, we recommend to implement endurance-dominated exercise programs in type 2 diabetic patients because it is feasible, safe and effective by improving aerobic capacity and gait characteristics.},
  language  = {en}
}
@phdthesis{Krueger2005,
  author    = {Kr{\"u}ger, Tom},
  title     = {Zum Einfluss der Lateralit{\"a}t in zyklischen Sportarten bei Nachwuchsathleten},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-5810},
  school      = {Universit{\"a}t Potsdam},
  year      = {2005},
  abstract  = {Die Auspr{\"a}gung der Lateralit{\"a}t der K{\"o}rperextremit{\"a}ten steht in engem Zusammenhang mit der Hemisph{\"a}renspezialisierung des menschlichen Gehirns. Die Lateralit{\"a}t und die Dominanz einer Hemisph{\"a}re mit ihren Auswirkungen auf die Leistungsf{\"a}higkeit ist ein bislang unvollst{\"a}ndig untersuchtes Ph{\"a}nomen im Sport. In der vorliegenden Arbeit soll daher die Bedeutung der Seitigkeitsauspr{\"a}gung im Rahmen sportlicher Bewegungsabl{\"a}ufe gepr{\"u}ft werden. Sowohl bei Messungen im "Freiwasser", als auch in der "Kanu-Gegenstromanlage" im Bereich des Kanurennsportes werden seit einigen Jahren sich in Qualit{\"a}t und Quantit{\"a}t unterscheidende Kraft-Zeit-Funktionen der linken und rechten K{\"o}rperseite beobachtet, die zwar dokumentiert, aber bislang ungepr{\"u}ft in ihrer Bedeutung als leistungsbeeinflussend angenommen werden. Im Zeitraum von Oktober 1997 bis Oktober 2000 wurden 275 Kajakfahrer und Canadierfahrer im Alter zwischen 11 und 20 Jahren zweimal j{\"a}hrlich (M{\"a}rz und Oktober) mit einem umfangreichen trainings- und bewegungswissenschaftlichen sowie biomechanischen Instrumentarium untersucht. Die Athleten geh{\"o}ren zum Nachwuchs- und Anschlusskader des LKV Brandenburg. Schwerpunkt der Fragestellung ist der Zusammenhang von auftretenden Kraftdifferenzen zwischen der linken und rechten oberen Extremit{\"a}t und sportartspezifischen Leistungen unter Laborbedingungen und Feldbedingungen. Es wurden objektive Daten zu ausgew{\"a}hlten Kraftf{\"a}higkeiten der oberen Arm-Beuge-Schlinge an einem Kraftdiagnoseger{\"a}t, Kraftverl{\"a}ufe am Messpaddel w{\"a}hrend Leistungs{\"u}berpr{\"u}fungen im "Kanu-Gegenstromkanal" und im "Freiwasser" {\"u}ber 250 m und 2.000 m im Jahresverlauf erhoben. Die Ergebnisse zeigen einen Trend der im Altersverlauf ansteigenden Differenz der Mittelwertunterschiede in der Maximalkraft zwischen dem linken und rechten Arm. Bei bestehenden Maximalkraftdifferenzen zwischen linker und rechter oberer Extremit{\"a}t in der L{\"a}ngsschnittgruppe liegen die Leistungen mit dem rechten Arm deutlich {\"u}ber den Kraftleistungen des linken Arms und sind nicht zuf{\"a}llig. Mit steigendem Maximalkraftniveau nimmt {\"u}berraschenderweise auch die Differenz der Maximalkraft zwischen der linken und rechten oberen Extremit{\"a}t trotz bilateralen Trainings zu. Die Ergebnisse der EMG-Analyse best{\"a}tigen, dass die Maximalkraft leistungsbestimmend f{\"u}r die Bootsleistungen ist. In den EMG-Signalverl{\"a}ufen werden die unterschiedlichen Belastungen der Labor- und Feldbedingungen mit individuellen Charakteristika nachgezeichnet. Deutlich unterscheiden sich die Kraftverl{\"a}ufe im "Freiwasser" gegen{\"u}ber den Kraftverl{\"a}ufen in der "Kanu-Gegenstromanlage". Bei der vorliegenden Untersuchung handelt es sich um eine erste empirische Arbeit zur Auswirkung von Seitigkeitsunterschieden in zyklischen Sportarten auf der Expertiseebene. In der Untersuchung wurden methodische Verfahren eingesetzt, die dem derzeitigen Forschungsstand in der Trainings- und Bewegungswissenschaft entsprechen. Neben varianzanalytischen Verfahren der Auswertung zur Darstellung von Mittelwertunterschieden und Zusammenh{\"a}nge pr{\"u}fenden Verfahren wurden ebenso explorative EMG-Analysen angewandt. Die Ergebnisse aus dem L{\"a}ngsschnitt belegen bei ausschließlich rechtsh{\"a}ndigen Probanden, dass die Schlussfolgerung von bevorzugter Extremit{\"a}t auf ein h{\"o}heres Kraftniveau nicht eineindeutig ist. Zwischen den oberen Extremit{\"a}ten bei Kanurennsportlern bestehen nicht nur zuf{\"a}llige Kraftunterschiede, trotz des bilateralen Trainings. Kontrovers diskutiert wird die Beziehung von bevorzugter Extremit{\"a}t und der H{\"o}he der Kraftentfaltung. Im Alltagsverst{\"a}ndnis wird h{\"a}ufig angenommen, dass ein h{\"o}heres Maximalkraftniveau in der Extremit{\"a}t vorliegen muss, die auch die bevorzugte (z.B. Schreibhand) ist (WIRTH \& LIPHARDT, 1999). Diese Eindeutigkeit konnte in der durchgef{\"u}hrten Untersuchung nicht best{\"a}tigt werden. Wie die Ergebnisse dieser Untersuchung deutlich zeigen, nimmt mit der h{\"o}heren Maximalkraft aber auch die Differenz der Kraftleistungen zwischen dem linken und rechten Arm bei bilateral ausgerichtetem Training zu. FISCHER (1988; 1992) wies nach, dass sich ein Training auf der subdominanten Seite in einem kontralateralen Leistungstransfer auf der dominanten Seite positiv auswirkte. Erkenntnisse von KUHN (1986) und HOLLMANN \& HETTINGER (2000) unterst{\"u}tzen nachhaltig die Ergebnisse. Die EMG-Ergebnisse zeigen die individuelle Reaktion auf die Belastungsanforderungen. Die elektromyographischen Daten beziehen sich auf den neuromuskul{\"a}ren Komplex. Somit sprechen hohe Amplitudenwerte einerseits f{\"u}r eine hohe Innervation der beteiligten motorischen Einheiten an der Bewegungsausf{\"u}hrung und andererseits f{\"u}r einsetzende Erm{\"u}dungserscheinungen im Muskel. In Bezug auf die Erm{\"u}dung der oberen Extremit{\"a}tenmuskeln der rechten und linken Seite beschreiben WILLIAMS, SHARMA \& BILODEAU (2002) keine signifikanten Unterschiede zwischen der dominanten und nichtdominanten Handseite.},
  subject      = {Kanurennsport},
  language  = {de}
}
@phdthesis{Lesinski2019,
  author    = {Lesinski, Melanie},
  title     = {Modulating factors for drop jump performance},
  school      = {Universit{\"a}t Potsdam},
  pages     = {viii, 57, xiii},
  year      = {2019},
  abstract  = {Background and objectives: Drop jumps (DJs) are well-established exercise drills during plyometric training. Several sports are performed under unstable surface conditions (e.g., soccer, beach volleyball, gymnastics). To closely mimic sport-specific demands, plyometric training includes DJs on both stable and unstable surfaces. According to the mechanical properties of the unstable surface (e.g., thickness, stiffness), altered temporal, mechanical, and physiological demands have been reported from previous cross-sectional studies compared with stable conditions. However, given that the human body simultaneously interacts with various factors (e.g., drop height, footwear, gender) during DJs on unstable surfaces, the investigation of isolated effects of unstable surface conditions might not be sufficient for designing an effective and safe DJ stimulus. Instead, the combined investigation of different factors and their interaction with surface instability have to be taken into consideration. Therefore, the present doctoral thesis seeks to complement our knowledge by examining the main and interaction effects of surface instability, drop height, footwear, and gender on DJ performance, knee joint kinematics, and neuromuscular activation. Methods: Healthy male and female physically active sports science students aged 19-26 years participated in the cross-sectional studies. Jump performance, sagittal and frontal plane knee joint kinematics, and leg muscle activity were measured during DJs on stable (i.e., firm force plate) and (highly) unstable surfaces (i.e., one or two AIREX® balance pads) from different drop heights (i.e., 20 cm, 40 cm, 60 cm) or under multiple footwear conditions (i.e., barefoot, minimal shoes, cushioned shoes). Results: Findings revealed that surface instability caused a DJ performance decline, reduced sagittal plane knee joint kinematics, and lower leg muscle activity during DJs. Sagittal plane knee joint kinematics as well as leg muscle activity decreased even more with increasing surface instability (i.e., two vs. one AIREX® balance pads). Higher (60 cm) compared to lower drop heights (≤ 40 cm) resulted in a DJ performance decline. In addition, increased sagittal plane knee joint kinematics as well as higher shank muscle activity were found during DJs from higher (60 cm) compared to lower drop heights (≤ 40 cm). Footwear properties almost exclusively affected frontal plane knee joint kinematics, indicating larger maximum knee valgus angles when performing DJs barefoot compared to shod. Between the different shoe properties (i.e., minimal vs. cushioned shoes), no significant differences during DJs were found at all. Only a few significant surface-drop height as well as surface-footwear interactions were found during DJs. They mainly indicated that drop height- and footwear-related effects are more pronounced during DJs on unstable compared to stable surfaces. In this regard, the maximum knee valgus angle was significantly greater when performing DJs from high drop heights (60 cm), but only on highly unstable surface. Further, braking and push-off times were significantly longer when performing DJs barefoot compared to shod, but only on unstable surface. Finally, analyses indicated no significant interactions with the gender factor. Conclusions: The findings of the present cumulative thesis indicate that stable rather than unstable surfaces as well as moderate (≤ 40 cm) rather than high (60 cm) drop heights provide sufficient stimuli to perform DJs. Furthermore, findings suggest that DJs on highly unstable surfaces (i.e., two AIREX® balance pads) from high drop heights (60 cm) as well as barefoot compared to shod seem to increase maximal knee valgus angle/stress by providing a more harmful DJ stimulus. Neuromuscular activation strategies appear to be modified by surface instability and drop height. However, leg muscle activity is only marginally effected by footwear and by the interactions of various external factors i.e., surface instability, drop height, footwear). Finally, gender did not significantly modulate the main or interaction effects of the observed external factors during DJs.},
  language  = {en}
}
@article{MuehlbauerGranacherJockeletal.2013,
  author    = {M{\"u}hlbauer, Thomas and Granacher, Urs and Jockel, Bj{\"o}rn and Kittel, R{\´e}ne},
  title     = {Analyse der Muskelaktivit{\"a}t therapeutischer Kletter{\"u}bungen},
  series = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation},
  volume    = {27},
  journal   = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation},
  number    = {3},
  publisher = {Thieme},
  address   = {Stuttgart},
  issn      = {0932-0555},
  doi       = {10.1055/s-0033-1335595},
  pages     = {162 -- 168},
  year      = {2013},
  abstract  = {Background: Therapeutic climbing exercises are employed for the treatment of shoulder-and knee-joint injuries. However, there is a void in the literature regarding muscle activation levels during the performance of these exercises. Thus, the purpose of this study was to investigate differences in muscle activation during therapeutic climbing exercises depending on the degree of task difficulty. Participants/Material and Methods: A sample of 10 healthy subjects (sex: 4 females, 6 males; age: 27 +/- 3 years; climbing experience: 5 +/- 3 years) performed three shoulder girdle (i.e., wide shoulder pull, narrow shoulder pull, shoulder row) and two leg extensor (i.e., ascending frontal, ascending sidewards) exercises. Electromyographic (EMG) data were recorded on the right side for eleven muscles and then normalised using the maximum voluntary contractions for each muscle. Results: With increasing task difficulty, muscle activity in all but one muscle (i.e., m. trapezius ascendens) increased significantly for the three shoulder girdle exercises. For the two leg extensor exercises, an increase in task difficulty produced a tendency towards yet not significantly higher muscle activity. Conclusion: Shoulder row was the most effective therapeutic climbing exercise in the ability to activate muscles while showing the highest EMG signals. The absence of significant differences in muscle activity between the two leg extensor exercises indicates their equivalent use for muscle activation during therapy.},
  language  = {de}
}
@article{MuehlbauerMettlerRothetal.2014,
  author    = {M{\"u}hlbauer, Thomas and Mettler, Claude and Roth, Ralf and Granacher, Urs},
  title     = {One-leg standing performance and muscle activity: Are there limb differences?},
  series = {Journal of applied biomechanics},
  volume    = {30},
  journal   = {Journal of applied biomechanics},
  number    = {3},
  publisher = {Human Kinetics Publ.},
  address   = {Champaign},
  issn      = {1065-8483},
  doi       = {10.1123/jab.2013-0230},
  pages     = {407 -- 414},
  year      = {2014},
  abstract  = {The purpose of this study was to compare static balance performance and muscle activity during one-leg standing on the dominant and nondominant leg under various sensory conditions with increased levels of task difficulty. Thirty healthy young adults (age: 23 +/- 2 years) performed one-leg standing tests for 30 s under three sensory conditions (ie, eyes open/firm ground; eyes open/foam ground [elastic pad on top of the balance plate]; eyes closed/firm ground). Center of pressure displacements and activity of four lower leg muscles (ie, m. tibialis anterior [TA], m. soleus [SOL], m. gastrocnemius medialis [GAS], m. peroneus longus [PER]) were analyzed. An increase in sensory task difficulty resulted in deteriorated balance performance (P < .001, effect size [ES] = .57-2.54) and increased muscle activity (P < .001, ES = .50-1.11) for all but two muscles (ie, GAS, PER). However, regardless of the sensory condition, one-leg standing on the dominant as compared with the nondominant limb did not produce statistically significant differences in various balance (P > .05, ES = .06-.22) and electromyographic (P > .05, ES = .03-.13) measures. This indicates that the dominant and the nondominant leg can be used interchangeably during static one-leg balance testing in healthy young adults.},
  language  = {en}
}
@phdthesis{Mueller2017,
  author    = {M{\"u}ller, Juliane},
  title     = {Trunk loading and back pain},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-102428},
  school      = {Universit{\"a}t Potsdam},
  pages     = {ix, 123},
  year      = {2017},
  abstract  = {An essential function of the trunk is the compensation of external forces and loads in order to guarantee stability. Stabilising the trunk during sudden, repetitive loading in everyday tasks, as well as during performance is important in order to protect against injury. Hence, reduced trunk stability is accepted as a risk factor for the development of back pain (BP). An altered activity pattern including extended response and activation times as well as increased co-contraction of the trunk muscles as well as a reduced range of motion and increased movement variability of the trunk are evident in back pain patients (BPP). These differences to healthy controls (H) have been evaluated primarily in quasi-static test situations involving isolated loading directly to the trunk. Nevertheless, transferability to everyday, dynamic situations is under debate. Therefore, the aim of this project is to analyse 3-dimensional motion and neuromuscular reflex activity of the trunk as response to dynamic trunk loading in healthy (H) and back pain patients (BPP). A measurement tool was developed to assess trunk stability, consisting of dynamic test situations. During these tests, loading of the trunk is generated by the upper and lower limbs with and without additional perturbation. Therefore, lifting of objects and stumbling while walking are adequate represents. With the help of a 12-lead EMG, neuromuscular activity of the muscles encompassing the trunk was assessed. In addition, three-dimensional trunk motion was analysed using a newly developed multi-segmental trunk model. The set-up was checked for reproducibility as well as validity. Afterwards, the defined measurement set-up was applied to assess trunk stability in comparisons of healthy and back pain patients. Clinically acceptable to excellent reliability could be shown for the methods (EMG/kinematics) used in the test situations. No changes in trunk motion pattern could be observed in healthy adults during continuous loading (lifting of objects) of different weights. In contrast, sudden loading of the trunk through perturbations to the lower limbs during walking led to an increased neuromuscular activity and ROM of the trunk. Moreover, BPP showed a delayed muscle response time and extended duration until maximum neuromuscular activity in response to sudden walking perturbations compared to healthy controls. In addition, a reduced lateral flexion of the trunk during perturbation could be shown in BPP. It is concluded that perturbed gait seems suitable to provoke higher demands on trunk stability in adults. The altered neuromuscular and kinematic compensation pattern in back pain patients (BPP) can be interpreted as increased spine loading and reduced trunk stability in patients. Therefore, this novel assessment of trunk stability is suitable to identify deficits in BPP. Assignment of affected BPP to therapy interventions with focus on stabilisation of the trunk aiming to improve neuromuscular control in dynamic situations is implied. Hence, sensorimotor training (SMT) to enhance trunk stability and compensation of unexpected sudden loading should be preferred.},
  language  = {en}
}
@article{PrieskeMuehlbauerBordeetal.2016,
  author    = {Prieske, Olaf and M{\"u}hlbauer, Thomas and Borde, Ron and Gube, M. and Bruhn, S. and Behm, David George and Granacher, Urs},
  title     = {Neuromuscular and athletic performance following core strength training in elite youth soccer: Role of instability},
  series = {Learning and individual differences},
  volume    = {26},
  journal   = {Learning and individual differences},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0905-7188},
  doi       = {10.1111/sms.12403},
  pages     = {48 -- 56},
  year      = {2016},
  abstract  = {Cross-sectional studies revealed that inclusion of unstable elements in core-strengthening exercises produced increases in trunk muscle activity and thus potential extra stimuli to induce more pronounced performance enhancements in youth athletes. Thus, the purpose of the study was to investigate changes in neuromuscular and athletic performance following core strength training performed on unstable (CSTU) compared with stable surfaces (CSTS) in youth soccer players. Thirty-nine male elite soccer players (age: 17 +/- 1 years) were assigned to two groups performing a progressive core strength-training program for 9 weeks (2-3 times/week) in addition to regular in-season soccer training. CSTS group conducted core exercises on stable (i.e., floor, bench) and CSTU group on unstable (e.g., Thera-Band (R) Stability Trainer, Togu (c) Swiss ball) surfaces. Measurements included tests for assessing trunk muscle strength/activation, countermovement jump height, sprint time, agility time, and kicking performance. Statistical analysis revealed significant main effects of test (pre vs post) for trunk extensor strength (5\%, P<0.05, d=0.86), 10-20-m sprint time (3\%, P<0.05, d=2.56), and kicking performance (1\%, P<0.01, d=1.28). No significant Groupxtest interactions were observed for any variable. In conclusion, trunk muscle strength, sprint, and kicking performance improved following CSTU and CSTS when conducted in combination with regular soccer training.},
  language  = {en}
}
@article{PrieskeWickGranacher2014,
  author    = {Prieske, Olaf and Wick, Ditmar and Granacher, Urs},
  title     = {Intrasession and intersession reliability in maximal and explosive isometric torque production of the elbow flexors},
  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    = {6},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {1064-8011},
  pages     = {1771 -- 1777},
  year      = {2014},
  abstract  = {The purpose of this study was to assess intrasession and intersession reliability of maximal and explosive isometric torque production of the elbow flexors and its respective neuromuscular activation pattern. Subjects (13 men, age: 24.8 +/- 3.1 years, height: 1.9 +/- 0.1 m, body mass: 83.7 +/- 12.7 kg; and 6 women, age: 26.5 +/- 1.4 years, height: 1.7 +/- 0.1 m, body mass: 62.7 +/- 7.0 kg) were tested and retested 2-7 days later performing unilateral maximal isometric elbow flexions. Absolute (coefficient of variation[CV], test-retest variability[TRV], Bland-Altman plots with 95\% limits of agreement) and relative reliability statistics (intraclass correlation coefficient) were calculated for various mechanical (i.e., maximal isometric torque, rate of torque development, impulse) and electromyographical measures (i.e., mean average voltage) at different time intervals relative to onset of torque (i. e., 30, 50, 100, 200, 300, 400, 100-200 ms). Intraclass correlation coefficient values were >= 0.61 for all mechanical and electromyographical measures and time intervals indicating good to excellent intrasession and intersession reliability. BlandAltman plots confirmed these findings by showing that only 0-2 (<= 3.3\%) data points were beyond the limits of agreement. Regarding torque and electromyographic measures, CV (11.9-32.3\%) and TRV (18.4-53.8\%) values were high during the early intervals of torque development (<= 100 ms) indicating high variability. During the later intervals (>100 ms), lower CV (i. e., 5.0-29.9\%) and TRV values (i.e., 5.4-34.6\%) were observed indicating lower variability. The present study revealed that neuromuscular performance during explosive torque production of the elbow flexors is reproducible in time intervals >100 ms after onset of isometric actions, whereas during earlier time intervals variability is high.},
  language  = {en}
}