TY - JOUR
A1 - Sammoud, Senda
A1 - Negra, Yassine
A1 - Bouguezzi, Raja
A1 - Hachana, Younes
A1 - Granacher, Urs
A1 - Chaabene, Helmi
T1 - The effects of plyometric jump training on jump and sport-specific performances in prepubertal female swimmers
JF - Journal of exercise science and fitness : JESF : official journal of The Society of Chinese Scholars on Exercise Physiology and Fitness and Hong Kong Association of Sports Medicine & Sports Science
N2 - Background/objective
Dry land-training (e.g., plyometric jump training) can be a useful mean to improve swimming performance. This study examined the effects of an 8-week plyometric jump training (PJT) program on jump and sport-specific performances in prepubertal female swimmers.
Methods
Twenty-two girls were randomly assigned to either a plyometric jump training group (PJTG; n = 12, age: 10.01 ± 0.57 years, maturity-offset = -1.50 ± 0.50, body mass = 36.39 ± 6.32 kg, body height = 146.90 ± 7.62 cm, body mass index = 16.50 ± 1.73 kg/m2) or an active control (CG; n = 10, age: 10.50 ± 0.28 years, maturity-offset = -1.34 ± 0.51, body mass = 38.41 ± 9.42 kg, body height = 143.60 ± 5.05 cm, body mass index = 18.48 ± 3.77 kg/m2). Pre- and post-training, tests were conducted for the assessment of muscle power (e.g., countermovement-jump [CMJ], standing-long-jump [SLJ]). Sport-specific-performances were tested using the timed 25 and 50-m front crawl with a diving-start, timed 25-m front crawl without push-off from the wall (25-m WP), and a timed 25-m kick without push-off from the wall (25-m KWP).
Results
Findings showed a significant main effect of time for the CMJ (d = 0.78), the SLJ (d = 0.91), 25-m front crawl test (d = 2.5), and the 25-m-KWP (d = 1.38) test. Significant group × time interactions were found for CMJ, SLJ, 25-m front crawl, 50-m front crawl, 25-m KWP, and 25-m WP test (d = 0.29–1.63) in favor of PJTG (d = 1.34–3.50). No significant pre-post changes were found for CG (p > 0.05).
Conclusion
In sum, PJT is effective in improving muscle power and sport-specific performances in prepubertal swimmers. Therefore, PJT should be included from an early start into the regular training program of swimmers.
KW - Stretch-shortening cycle
KW - Young swimmers
KW - Swimming performance
Y1 - 2020
U6 - https://doi.org/10.1016/j.jesf.2020.07.003
SN - 1728-869x
VL - 19
IS - 1
SP - 25
EP - 31
PB - Elsevier
CY - Singapore
ER -
TY - JOUR
A1 - Hammami, Raouf
A1 - Chaabene, Helmi
A1 - Kharrat, Fatma
A1 - Werfelli, Hanen
A1 - Duncan, Michael
A1 - Rebai, Haithem
A1 - Granacher, Urs
T1 - Acute effects of different balance exercise types on selected measures of physical fitness in youth female volleyball players
JF - BMC Sports Science, Medicine and Rehabilitation
N2 - Background
Earlier studies have shown that balance training (BT) has the potential to induce performance enhancements in selected components of physical fitness (i.e., balance, muscle strength, power, speed). While there is ample evidence on the long-term effects of BT on components of physical fitness in youth, less is known on the short-term or acute effects of single BT sessions on selected measures of physical fitness.
Objective
To examine the acute effects of different balance exercise types on balance, change-of-direction (CoD) speed, and jump performance in youth female volleyball players.
Methods
Eleven female players aged 14 years participated in this study. Three types of balance exercises (i.e., anterior, posterolateral, rotational type) were conducted in randomized order. For each exercise, 3 sets including 5 repetitions were performed. Before and after the performance of the balance exercises, participants were tested for their static balance (center of pressure surface area [CoP SA] and velocity [CoP V]) on foam and firm surfaces, CoD speed (T-Half test), and vertical jump height (countermovement jump [CMJ] height). A 3 (condition: anterior, mediolateral, rotational balance exercise type) × 2 (time: pre, post) analysis of variance was computed with repeated measures on time.
Results
Findings showed no significant condition × time interactions for all outcome measures (p > 0.05). However, there were small main effects of time for CoP SA on firm and foam surfaces (both d = 0.38; all p < 0.05) with no effect for CoP V on both surface conditions (p > 0.05). For CoD speed, findings showed a large main effect of time (d = 0.91; p < 0.001). However, for CMJ height, no main effect of time was observed (p > 0.05).
Conclusions
Overall, our results indicated small-to-large changes in balance and CoD speed performances but not in CMJ height in youth female volleyball players, regardless of the balance exercise type. Accordingly, it is recommended to regularly integrate balance exercises before the performance of sport-specific training to optimize performance development in youth female volleyball players.
KW - Postural stability
KW - Conditioning activity
KW - Short‐term effect
KW - Team sports
KW - Youth
Y1 - 2021
U6 - https://doi.org/10.1186/s13102-021-00249-5
SN - 1758-2555
VL - 13
PB - BioMed Central
CY - London
ER -
TY - JOUR
A1 - Brahms, Clemens Markus
A1 - Hortobágyi, Tibor
A1 - Kressig, Reto W.
A1 - Granacher, Urs
T1 - The Interaction between mobility status and exercise specificity in older adults
JF - Exercise and sport sciences reviews
N2 - Many adults older than 60 yr experience mobility limitations. Although physical exercise improves older adults' mobility, differences in baseline mobility produce large variations in individual responses to interventions, and these responses could further vary by the type and dose of exercise. Here, we propose an exercise prescription model for older adults based on their current mobility status.
KW - exercise prescription
KW - training intervention
KW - walking speed
KW - activities
KW - of daily living
KW - elderly
Y1 - 2021
U6 - https://doi.org/10.1249/JES.0000000000000237
SN - 0091-6331
SN - 1538-3008
VL - 49
IS - 1
SP - 15
EP - 22
PB - Lippincott Williams & Wilkins
CY - Hagerstown, Md.
ER -
TY - JOUR
A1 - Helm, Norman
A1 - Prieske, Olaf
A1 - Mühlbauer, Thomas
A1 - Krüger, Tom
A1 - Granacher, Urs
T1 - Effects of judo-specific resistance training on kinetic and electromyographic parameters of pulling exercises in judo athletes
T1 - Effekte eines judospezifischen Messplatztrainings auf kinetische und elektromyografische Parameter des Anreißens bei Wurfeingangsbewegungen von Judoka
JF - Sportverletzung, Sportschaden : Grundlagen, Prävention, Rehabilitation
N2 - Background In judo, rapid force production during pulling movements is an important component of athletic performance, which is why this capacity needs to be specifically exercised in judo. This study aimed at examining the effects of a judo-specific resistance training program using a judo ergometer system (PTJ) versus a traditional resistance training regime using a partner (PTP) on kinetics and muscle activity of judo-specific pulling exercises. Method Twenty-four male judo athletes (age: 22 +/- 4 years, training experience: 15 +/- 3 years) were randomly assigned to two groups. In a crossover design, the first group completed a 4-week PTJ followed by four weeks of PTP (each with three sessions per week). The second group conducted PTP prior to PTJ. PTJ and PTP were completed in addition to regular training. Before, 4 weeks and 8 weeks after training, tests were conducted to assess judo-specific pulling kinetics (i.e. maximal force, rate of force development [RFD], mechanical work) and electromyographic (EMG) shoulder/trunk muscle activity (i.e. biceps brachii muscle, deltoid muscle, trapezius muscle, erector spinae muscle) during pulling movements using a judo ergometer as well as unspecific strength tests (i.e. bench-pull, pull-ups). Results The statistical analysis revealed that in both groups ergometer pulling kinetics (p<.05, 0.83 <= d <= 1.77) and EMG activity (p<.05; 1.07 <= d <= 2.25) were significantly enhanced following 8 weeks of training. In addition, significantly larger gains in RFD, mechanical work, and EMG activity (i.e. deltoid muscle, erector spinae muscle, trapezius muscle) were found following PTJ compared to PTP (p<.05, 1.25 <= d <= 2.79). No significant enhancements were observed with the unspecific strength tests. Conclusion Our findings indicate that PTJ is superior to PTP regarding training-induced improvements in force production and muscle activity during judo-specific pulling exercises. Performance enhancements may partly be attributed to neural adaptations. No transfer effects on unspecific strength tests were detected following PTJ and PTP.
N2 - Hintergrund Schnellkräftige Wurfeingangsbewegungen stellen im Judo entscheidende Voraussetzungen für den Wettkampferfolg dar, weshalb das Training der Anrissbewegung ein zentrales Element des judospezifischen Trainings darstellt. Das Ziel der Studie bestand darin, die Effekte eines Anrisstrainings mit einem Judoergometer-System (ATJ) gegenüber einem tradierten Anrisstraining mit Partner (ATP) auf kinetische und elektromyografische Parameter des Anreißens bei Wurfeingangsbewegungen von Judoka zu untersuchen. Methode Männliche leistungsorientierte Judoka (N = 24, Alter: 22 ± 4 Jahre; Trainingserfahrung: 15 ± 3 Jahre) wurden randomisiert in zwei Gruppen aufgeteilt. Im Crossover-Design absolvierte die erste Gruppe über vier Wochen ein ATJ gefolgt von vier Wochen ATP (je 3x/ Woche). Die zweite Gruppe führte beide Trainingsvarianten in umgekehrter Reihenfolge durch. ATJ und ATP wurden zusätzlich zum bestehenden Training absolviert. Vor dem Training sowie nach vier und nach acht Wochen Training wurden Tests zur Erfassung kinetischer Parameter (dynamisch-realisierte Maximalkraft, Explosivkraft, mechanische Arbeit) und elektromyografischer (EMG) Schulter-/ Rumpfmuskelaktivitäten (M. biceps brachii, M. deltoideus, M. trapezius, M. erector spinae) für die Hub- und Zugarmseite bei Wurfeingangsbewegungen am Judoergometer sowie sportartunspezifische Krafttests (d. h. Liegend-Anreißen, Klimmziehen) durchgeführt.
Ergebnisse Die Ergebnisse der statistischen Analyse ergaben über den gesamten Interventionszeitraum (8 Wochen) für beide Trainingsgruppen signifikante Verbesserungen der kinetischen Parameter (p <,05; 0,83 ≤d≤ 1,77) und EMG-Aktivitäten (p <,05; 1,07 ≤d≤ 2,25). Darüber hinaus zeigten sich größere Zuwachsraten in der Explosivkraft, der mechanischen Arbeit und den Schulter-/Rumpfmuskelaktivitäten (M. deltoideus, M. erector spinae, M. trapezius) zugunsten von ATJ im Vergleich zu ATP (p <,05; 1,25 ≤d≤ 2,79). Für die sportartunspezifischen Kraftwerte wurden keine signifikanten Veränderungen festgestellt.
Schlussfolgerung Die vorliegenden Ergebnisse zeigen, dass ATJ gegenüber ATP größere Steigerungsraten von kinetischen und elektromyografischen Parametern des Anreißens bei Wurfeingangsbewegungen von Judoka bewirkt. Die trainingsbedingten Leistungssteigerungen scheinen zumindest teilweise auf neuronalen Anpassungen zu beruhen.
KW - combat sport
KW - athletic performance
KW - specific strength training
KW - surface electromyography
KW - Kampfsport
KW - sportliche Leistung
KW - spezifisches Krafttraining
KW - Oberflächenelektromyografie
Y1 - 2018
U6 - https://doi.org/10.1055/s-0043-122781
SN - 0932-0555
SN - 1439-1236
VL - 32
IS - 2
SP - 134
EP - 142
PB - Thieme
CY - Stuttgart
ER -
TY - JOUR
A1 - Jafarnezhadgero, AmirAli
A1 - Ghorbanloo, Farshad
A1 - Fatollahi, Amir
A1 - Dionisio, Valdeci Carlos
A1 - Granacher, Urs
T1 - Effects of an elastic resistance band exercise program on kinetics and muscle activities during walking in young adults with genu valgus
BT - A double-blinded randomized controlled trial
JF - Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics
N2 - Background:
This double-blinded randomized-controlled-trial aimed to identify the effects of an elastic band resistance training on walking kinetics and muscle activities in young adults with genu valgus.
Methods:
Forty-two male young adults aged 22.5(2.7) years with genu valgus were randomly allocated to two experimental groups. The intervention group (n = 21) conducted a 14-weeks elastic band resistance training. The control group was passive during the intervention period and received the same treatment after the post-tests. Pre and post training, ground reaction forces and lower limb muscle activities were recorded during walking.
Findings:
Results revealed significant group-by-time interactions for peak medial ground reaction force and timeto-peak for posterior ground reaction force in favor of the intervention group (p < 0.012; d = 0.83-3.76). Resistance training with elastic bands resulted in significantly larger peak medial ground reaction force (p < 0.001; d = 1.45) and longer time-to-peak for posterior ground reaction force (p < 0.001; d = 1.85). Finding showed significant group-by-time interactions for peak positive free moment amplitudes in favor of the intervention group (p < 0.001; d = 1.18-2.02). Resistance training resulted in a lower peak positive free moment amplitude (p = 0.001; d = 1.46). With regards to muscle activities, the analysis revealed significant group-by time interactions for rectus femoris and gluteus medius activities during the push-off phase in favor of the intervention group (p < 0.038; d = 0.68-0.89). Resistance training induced higher rectus femoris (p = 0.038; d = 0.84) and gluteus medius (p = 0.007; d = 0.54) activities.
Interpretation:
This study proved the effectiveness of resistance training using elastic bands on kinetics and muscle activities during walking in male adults with genu valgus disorder. Given that this training regime is low cost, effective, and easy-to-administer, we suggest that it should be implemented as a rehabilitative or preventive means for young adults with genu valgus.
KW - Free moment
KW - Gait
KW - Knee valgus
KW - Loading rate
KW - Theraband training
Y1 - 2021
U6 - https://doi.org/10.1016/j.clinbiomech.2020.105215
SN - 0268-0033
SN - 1879-1271
VL - 81
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Wick, Kristin
A1 - Kriemler, Susi
A1 - Granacher, Urs
T1 - Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children
JF - Journal of strength and conditioning research : the research journal of the NSCA
N2 - Wick, K, Kriemler, S, and Granacher, U. Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children. J Strength Cond Res 35(4): 983-990, 2021-Childhood is characterized by high neuroplasticity that affords qualitative rather than quantitative components of physical activity to maximize the potential to sufficiently develop motor skills and foster long-term engagement in regular physical activity. This study examined the effects of an integrative strength-dominated exercise program on measures of physical fitness and cognitive performance in preschool children. Children aged 4-6 years from 3 kindergartens were randomized into an intervention (INT) group (n = 32) or a control group (n = 22). The 10-week intervention period was conducted 3 times per week (each session lasted 30 minutes) and included exercises for the promotion of muscle strength and power, coordination, and balance. Pre and post training, tests were conducted for the assessment of muscle strength (i.e., handgrip strength), muscle power (i.e., standing long jump), balance (i.e., timed single-leg stand), coordination (hopping on right/left leg), and attentional span (i.e., "Konzentrations-Handlungsverfahren fur Vorschulkinder" [concentration-action procedure for preschoolers]). Results from 2 x 2 repeated-measures analysis of covariance revealed a significant (p <= 0.05) and near significant (p = 0.051) group x time interaction for the standing long jump test and the Konzentrations-Handlungsverfahren. Post hoc tests showed significant pre-post changes for the INT (p < 0.001; d = 1.53) but not the CON (p = 0.72; d = 0.83). Our results indicate that a 10-week strength-dominated exercise program increased jump performance with a concomitant trend toward improvements in attentional capacity of preschool children. Thus, we recommend implementing this type of exercise program for preschoolers.
KW - motor skills
KW - cognitive skills
KW - attention
KW - kindergarten
KW - structured
KW - physical activity program
Y1 - 2021
U6 - https://doi.org/10.1519/JSC.0000000000003942
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - 4
SP - 983
EP - 990
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Jafarnezhadgero, Amir Ali
A1 - Fatollahi, Amir
A1 - Granacher, Urs
T1 - Eight weeks of exercising on sand has positive effects on biomechanics of walking and muscle activities in individuals with pronated feet
BT - a randomized double-blinded controlled trial
JF - Sports : open access journal
N2 - This study aimed to investigate the effects of eight weeks of barefoot running exercise on sand versus control on measures of walking kinetics and muscle activities in individuals with diagnosed pronated feet. Sixty physically active male adults with pronated feet were randomly allocated into an intervention or a waiting control group. The intervention group conducted an 8-weeks progressive barefoot running exercise program on sand (e.g., short sprints) with three weekly sessions. Pre and post intervention, participants walked at a constant speed of 1.3 m/s +/- 5% on a 18 m walkway with a force plate embedded in the middle of the walkway. Results showed significant group-by-time interactions for peak impact vertical and lateral ground reaction forces. Training but not control resulted in significantly lower peak impact vertical and lateral ground reaction forces. Significant group-by-time interactions were observed for vastus lateralis activity during the loading phase. Training-induced increases were found for the vastus lateralis in the intervention but not in the control group. This study revealed that the applied exercise program is a suitable means to absorb ground reaction forces (e.g., lower impact vertical and lateral peaks) and increase activities of selected lower limb muscles (e.g., vastus lateralis) when walking on stable ground.
KW - flat foot
KW - free moment
KW - gait
KW - loading rate
KW - training
Y1 - 2022
U6 - https://doi.org/10.3390/sports10050070
SN - 2075-4663
VL - 10
IS - 5
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Saal, Christian
A1 - Chaabene, Helmi
A1 - Helm, Norman
A1 - Warnke, Torsten
A1 - Prieske, Olaf
T1 - Network analysis of associations between anthropometry, physical fitness, and sport-specific performance in young canoe sprint athletes
BT - The role of age and sex
JF - Frontiers in sports and active living
N2 - Introduction
Anthropometric and physical fitness data can predict sport-specific performance (e.g., canoe sprint race time) in young athletes. Of note, inter-item correlations (i.e., multicollinearity) may exist between tests assessing similar physical qualities. However, multicollinearity among tests may change across age and/or sex due to age-/sex-specific non-linear development of test performances. Therefore, the present study aimed at analyzing inter-item correlations between anthropometric, physical fitness, and sport-specific performance data as a function of age and sex in young canoe sprint athletes.
Methods
Anthropometric, physical fitness, and sport-specific performance data of 618 male and 297 female young canoe sprint athletes (discipline: male/female kayak, male canoe) were recorded during a national talent identification program between 1992 and 2019. For each discipline, a correlation matrix (i.e., network analysis) was calculated for age category (U13, U14, U15, U16) and sex including anthropometrics (e.g., standing body height, body mass), physical fitness (e.g., cardiorespiratory endurance, muscle power), and sport-specific performance (i.e., 250 and 2,000-m on-water canoe sprint time). Network plots were used to explore the correlation patterns by visual inspection. Further, trimmed means (mu(trimmed)) of inter-item Pearson's correlations coefficients were calculated for each discipline, age category, and sex. Effects of age and sex were analyzed using one-way ANOVAs.
Results
Visual inspection revealed consistent associations among anthropometric measures across age categories, irrespective of sex. Further, associations between physical fitness and sport-specific performance were lower with increasing age, particularly in males. In this sense, statistically significant differences for mu(trimmed) were observed in male canoeists (p < 0.01, xi = 0.36) and male kayakers (p < 0.01, xi = 0.38) with lower mu(trimmed) in older compared with younger athletes (i.e., >= U15). For female kayakers, no statistically significant effect of age on mu(trimmed) was observed (p = 0.34, xi = 0.14).
Discussion
Our study revealed that inter-item correlation patterns (i.e., multicollinearity) of anthropometric, physical fitness, and sport-specific performance measures were lower in older (U15, U16) versus younger (U13, U14) male canoe sprint athletes but not in females. Thus, age and sex should be considered to identify predictors for sport-specific performance and design effective testing batteries for talent identification programs in canoe sprint athletes.
KW - talent identification
KW - youth sports [MeSH]
KW - athletic performance
KW - race
KW - time
KW - relationship
KW - multicollinearity
Y1 - 2022
U6 - https://doi.org/10.3389/fspor.2022.1038350
SN - 2624-9367
VL - 4
PB - Frontiers Media
CY - Lausanne
ER -
TY - GEN
A1 - Wick, Kristin
A1 - Leeger-Aschmann, Claudia S.
A1 - Monn, Nico D.
A1 - Radtke, Thomas
A1 - Ott, Laura V.
A1 - Rebholz, Cornelia E.
A1 - Cruz, Sergio
A1 - Gerber, Natalie
A1 - Schmutz, Einat A.
A1 - Puder, Jardena J.
A1 - Munsch, Simone
A1 - Kakebeeke, Tanja H.
A1 - Jenni, Oskar G.
A1 - Granacher, Urs
A1 - Kriemler, Susi
T1 - Interventions to promote fundamental movement skills in childcare and kindergarten
BT - a systematic review and meta-analysis
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Background
Proficiency in fundamental movement skills (FMS) lays the foundation for being physically active and developing more complex motor skills. Improving these motor skills may provide enhanced opportunities for the development of a variety of perceptual, social, and cognitive skills.
Objective
The objective of this systematic review and meta-analysis was to assess the effects of FMS interventions on actual FMS, targeting typically developing young children.
Method
Searches in seven databases (CINAHL, Embase, MEDLINE, PsycINFO, PubMed, Scopus, Web of Science) up to August 2015 were completed. Trials with children (aged 2-6 years) in childcare or kindergarten settings that applied FMS-enhancing intervention programs of at least 4 weeks and meeting the inclusion criteria were included. Standardized data extraction forms were used. Risk of bias was assessed using a standard scoring scheme (Effective Public Health Practice Project-Quality Assessment Tool for Quantitative Studies [EPHPP]). We calculated effects on overall FMS, object control and locomotor subscales (OCS and LMS) by weighted standardized mean differences (SMDbetween) using random-effects models. Certainty in training effects was evaluated using GRADE (Grading of Recommendations Assessment, Development, and Evaluation System).
Results
Thirty trials (15 randomized controlled trials and 15 controlled trials) involving 6126 preschoolers (aged 3.3-5.5 years) revealed significant differences among groups in favor of the intervention group (INT) with small-to-large effects on overall FMS (SMDbetween 0.46), OCS (SMDbetween 1.36), and LMS (SMDbetween 0.94). Our certainty in the treatment estimates based on GRADE is very low.
Conclusions
Although there is relevant effectiveness of programs to improve FMS proficiency in healthy young children, they need to be interpreted with care as they are based on low-quality evidence and immediate post-intervention effects without long-term follow-up.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 702
KW - motor skill
KW - high effect size
KW - fundamental movement skill
KW - motivational climate
KW - locomotor skill
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-435463
SN - 1866-8364
IS - 702
ER -
TY - GEN
A1 - El-Ashker, Said
A1 - Chaabene, Helmi
A1 - Negra, Yassine
A1 - Prieske, Olaf
A1 - Granacher, Urs
T1 - Cardio-Respiratory endurance responses following a simulated 3 x 3 minutes amateur boxing contest in elite level boxers
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - This study aimed at examining physiological responses (i.e., oxygen uptake [VO2] and heart rate [HR]) to a semi-contact 3 x 3-min format, amateur boxing combat simulation in elite level male boxers. Eleven boxers aged 21.4 +/- 2.1 years (body height 173.4 +/- 3.7, body mass 74.9 +/- 8.6 kg, body fat 12.1 +/- 1.9, training experience 5.7 +/- 1.3 years) volunteered to participate in this study. They performed a maximal graded aerobic test on a motor-driven treadmill to determine maximum oxygen uptake (VO2max), oxygen uptake (VO2AT) and heart rate (HRAT) at the anaerobic threshold, and maximal heart rate (HRmax). Additionally, VO2 and peak HR (HRpeak) were recorded following each boxing round. Results showed no significant differences between VO2max values derived from the treadmill running test and VO2 outcomes of the simulated boxing contest (p > 0.05, d = 0.02 to 0.39). However, HRmax and HRpeak recorded from the treadmill running test and the simulated amateur boxing contest, respectively, displayed significant differences regardless of the boxing round (p < 0.01, d = 1.60 to 3.00). In terms of VO2 outcomes during the simulated contest, no significant between-round differences were observed (p = 0.19, d = 0.17 to 0.73). Irrespective of the boxing round, the recorded VO2 was >90% of the VO2max. Likewise, HRpeak observed across the three boxing rounds were >= 90% of the HRmax. In summary, the simulated 3 x 3-min amateur boxing contest is highly demanding from a physiological standpoint. Thus, coaches are advised to systematically monitor internal training load for instance through rating of perceived exertion to optimize training-related adaptations and to prevent boxers from overreaching and/or overtraining.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 675
KW - aerobic metabolism
KW - physiological strain
KW - striking combat sports
KW - elite athletes
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-472338
SN - 1866-8364
IS - 675
ER -
TY - JOUR
A1 - Thiele, Dirk
A1 - Prieske, Olaf
A1 - Chaabene, Helmi
A1 - Granacher, Urs
T1 - Effects of strength training on physical fitness and sport-specific performance in recreational, sub-elite, and elite rowers
BT - a systematic review with meta-analysis
JF - Journal of sports sciences
N2 - The purpose of this systematic review with meta-analysis was to examine the effects of strength training (ST) on selected components of physical fitness (e.g., lower/upper limb maximal strength, muscular endurance, jump performance, cardiorespiratory endurance) and sport-specific performance in rowers. Only studies with an active control group were included if they examined the effects of ST on at least one proxy of physical fitness and/or sport-specific performance in rowers. Weighted and averaged standardized mean differences (SMD) were calculated using random-effects models. Subgroup analyses were computed to identify effects of ST type or expertise level on sport-specific performance. Our analyses revealed significant small effects of ST on lower limb maximal strength (SMD = 0.42, p = 0.05) and on sport-specific performance (SMD = 0.32, p = 0.05). Non-significant effects were found for upper limb maximal strength, upper/lower limb muscular endurance, jump performance, and cardiorespiratory endurance. Subgroup analyses for ST type and expertise level showed non-significant differences between the respective subgroups of rowers (p >= 0.32). Our systematic review with meta-analysis indicated that ST is an effective means for improving lower limb maximal strength and sport-specific performance in rowers. However, ST-induced effects are neither modulated by ST type nor rowers' expertise level.
KW - resistance training
KW - plyometric training
KW - on-water performance
KW - race
KW - time
KW - oarsmen
KW - athletic performance
Y1 - 2020
U6 - https://doi.org/10.1080/02640414.2020.1745502
SN - 0264-0414
SN - 1466-447X
VL - 38
IS - 10
SP - 1186
EP - 1195
PB - Routledge, Taylor & Francis Group
CY - Abingdon
ER -
TY - JOUR
A1 - Ramirez-Campillo, Rodrigo
A1 - Moran, Jason
A1 - Oliver, Jonathan L.
A1 - Pedley, Jason S.
A1 - Lloyd, Rhodri S.
A1 - Granacher, Urs
T1 - Programming Plyometric-Jump Training in Soccer: A Review
JF - Sports
N2 - The aim of this review was to describe and summarize the scientific literature on programming parameters related to jump or plyometric training in male and female soccer players of different ages and fitness levels. A literature search was conducted in the electronic databases PubMed, Web of Science and Scopus using keywords related to the main topic of this study (e.g., “ballistic” and “plyometric”). According to the PICOS framework, the population for the review was restricted to soccer players, involved in jump or plyometric training. Among 7556 identified studies, 90 were eligible for inclusion. Only 12 studies were found for females. Most studies (n = 52) were conducted with youth male players. Moreover, only 35 studies determined the effectiveness of a given jump training programming factor. Based on the limited available research, it seems that a dose of 7 weeks (1–2 sessions per week), with ~80 jumps (specific of combined types) per session, using near-maximal or maximal intensity, with adequate recovery between repetitions (<15 s), sets (≥30 s) and sessions (≥24–48 h), using progressive overload and taper strategies, using appropriate surfaces (e.g., grass), and applied in a well-rested state, when combined with other training methods, would increase the outcome of effective and safe plyometric-jump training interventions aimed at improving soccer players physical fitness. In conclusion, jump training is an effective and easy-to-administer training approach for youth, adult, male and female soccer players. However, optimal programming for plyometric-jump training in soccer is yet to be determined in future research.
KW - human physical conditioning
KW - exercise
KW - resistance training
KW - muscle strength
KW - plyometric exercise
KW - musculoskeletal and neural physiological phenomena
KW - movement
KW - sports
KW - football
KW - youth sport
Y1 - 2022
U6 - https://doi.org/10.3390/sports10060094
SN - 2075-4663
VL - 10
SP - 1
EP - 20
PB - MDPI
CY - Basel, Schweiz
ET - 6
ER -
TY - GEN
A1 - Chaabene, Helmi
A1 - Prieske, Olaf
A1 - Lesinski, Melanie
A1 - Sandau, Ingo
A1 - Granacher, Urs
T1 - Short-term seasonal development of anthropometry, body composition, physical fitness, and sport-specific performance in young olympic weightlifters
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - The aim of this study is to monitor short-term seasonal development of young Olympic weightlifters’ anthropometry, body composition, physical fitness, and sport-specific performance. Fifteen male weightlifters aged 13.2 ± 1.3 years participated in this study. Tests for the assessment of anthropometry (e.g., body-height, body-mass), body-composition (e.g., lean-body-mass, relative fat-mass), muscle strength (grip-strength), jump performance (drop-jump (DJ) height, countermovement-jump (CMJ) height, DJ contact time, DJ reactive-strength-index (RSI)), dynamic balance (Y-balance-test), and sport-specific performance (i.e., snatch and clean-and-jerk) were conducted at different time-points (i.e., T1 (baseline), T2 (9 weeks), T3 (20 weeks)). Strength tests (i.e., grip strength, clean-and-jerk and snatch) and training volume were normalized to body mass. Results showed small-to-large increases in body-height, body-mass, lean-body-mass, and lower-limbs lean-mass from T1-to-T2 and T2-to-T3 (∆0.7–6.7%; 0.1 ≤ d ≤ 1.2). For fat-mass, a significant small-sized decrease was found from T1-to-T2 (∆13.1%; d = 0.4) and a significant increase from T2-to-T3 (∆9.1%; d = 0.3). A significant main effect of time was observed for DJ contact time (d = 1.3) with a trend toward a significant decrease from T1-to-T2 (∆–15.3%; d = 0.66; p = 0.06). For RSI, significant small increases from T1-to-T2 (∆9.9%, d = 0.5) were noted. Additionally, a significant main effect of time was found for snatch (d = 2.7) and clean-and-jerk (d = 3.1) with significant small-to-moderate increases for both tests from T1-to-T2 and T2-to-T3 (∆4.6–11.3%, d = 0.33 to 0.64). The other tests did not change significantly over time (0.1 ≤ d ≤ 0.8). Results showed significantly higher training volume for sport-specific training during the second period compared with the first period (d = 2.2). Five months of Olympic weightlifting contributed to significant changes in anthropometry, body-composition, and sport-specific performance. However, hardly any significant gains were observed for measures of physical fitness. Coaches are advised to design training programs that target a variety of fitness components to lay an appropriate foundation for later performance as an elite athlete.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 685
KW - strength
KW - monitoring
KW - young athletes
KW - weight training
KW - somatic variables
KW - periodization
KW - training load
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-472609
SN - 1866-8364
IS - 685
ER -
TY - GEN
A1 - Sammoud, Senda
A1 - Negra, Yassine
A1 - Bouguezzi, Raja
A1 - Hachana, Younes
A1 - Granacher, Urs
A1 - Chaabene, Helmi
T1 - The effects of plyometric jump training on jump and sport-specific performances in prepubertal female swimmers
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Background/objective
Dry land-training (e.g., plyometric jump training) can be a useful mean to improve swimming performance. This study examined the effects of an 8-week plyometric jump training (PJT) program on jump and sport-specific performances in prepubertal female swimmers.
Methods
Twenty-two girls were randomly assigned to either a plyometric jump training group (PJTG; n = 12, age: 10.01 ± 0.57 years, maturity-offset = -1.50 ± 0.50, body mass = 36.39 ± 6.32 kg, body height = 146.90 ± 7.62 cm, body mass index = 16.50 ± 1.73 kg/m2) or an active control (CG; n = 10, age: 10.50 ± 0.28 years, maturity-offset = -1.34 ± 0.51, body mass = 38.41 ± 9.42 kg, body height = 143.60 ± 5.05 cm, body mass index = 18.48 ± 3.77 kg/m2). Pre- and post-training, tests were conducted for the assessment of muscle power (e.g., countermovement-jump [CMJ], standing-long-jump [SLJ]). Sport-specific-performances were tested using the timed 25 and 50-m front crawl with a diving-start, timed 25-m front crawl without push-off from the wall (25-m WP), and a timed 25-m kick without push-off from the wall (25-m KWP).
Results
Findings showed a significant main effect of time for the CMJ (d = 0.78), the SLJ (d = 0.91), 25-m front crawl test (d = 2.5), and the 25-m-KWP (d = 1.38) test. Significant group × time interactions were found for CMJ, SLJ, 25-m front crawl, 50-m front crawl, 25-m KWP, and 25-m WP test (d = 0.29–1.63) in favor of PJTG (d = 1.34–3.50). No significant pre-post changes were found for CG (p > 0.05).
Conclusion
In sum, PJT is effective in improving muscle power and sport-specific performances in prepubertal swimmers. Therefore, PJT should be included from an early start into the regular training program of swimmers.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 658
KW - Stretch-shortening cycle
KW - Young swimmers
KW - Swimming performance
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-478272
SN - 1866-8364
IS - 658
ER -
TY - GEN
A1 - Jebabli, Nidhal
A1 - Granacher, Urs
A1 - Selmi, Mohamed Amin
A1 - Al-Haddabi, Badriya
A1 - Behm, David George
A1 - Chaouachi, Anis
A1 - Haj Sassi, Radhouane
T1 - Listening to preferred music improved running performance without changing the pacing pattern during a 6 minute run test with young male adults
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Several studies have investigated the effects of music on both submaximal and maximal exercise performance at a constant work-rate. However, there is a lack of research that has examined the effects of music on the pacing strategy during self-paced exercise. The aim of this study was to examine the effects of preferred music on performance and pacing during a 6 min run test (6-MSPRT) in young male adults. Twenty healthy male participants volunteered for this study. They performed two randomly assigned trials (with or without music) of a 6-MSPRT three days apart. Mean running speed, the adopted pacing strategy, total distance covered (TDC), peak and mean heart rate (HRpeak, HRmean), blood lactate (3 min after the test), and rate of perceived exertion (RPE) were measured. Listening to preferred music during the 6-MSPRT resulted in significant TDC improvement (?10%; p = 0.016; effect size (ES) = 0.80). A significantly faster mean running speed was observed when listening to music compared with no music. The improvement of TDC in the present study is explained by a significant overall increase in speed (main effect for conditions) during the music trial. Music failed to modify pacing patterns as suggested by the similar reversed “J-shaped” profile during the two conditions. Blood-lactate concentrations were significantly reduced by 9% (p = 0.006, ES = 1.09) after the 6-MSPRT with music compared to those in the control condition. No statistically significant differences were found between the test conditions for HRpeak, HRmean, and RPE. Therefore, listening to preferred music can have positive effects on exercise performance during the 6-MSPRT, such as greater TDC, faster running speeds, and reduced blood lactate levels but has no effect on the pacing strategy.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 696
KW - RPE
KW - work-rate distribution
KW - blood lactate
KW - aerobic exercise
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-471884
SN - 1866-8364
IS - 696
ER -
TY - GEN
A1 - Sandau, Ingo
A1 - Granacher, Urs
T1 - Effects of the barbell load on the acceleration phase during the snatch in Olympic weightlifting
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - The load-depended loss of vertical barbell velocity at the end of the acceleration phase limits the maximum weight that can be lifted. Thus, the purpose of this study was to analyze how increased barbell loads affect the vertical barbell velocity in the sub-phases of the acceleration phase during the snatch. It was hypothesized that the load-dependent velocity loss at the end of the acceleration phase is primarily associated with a velocity loss during the 1st pull. For this purpose, 14 male elite weightlifters lifted seven load-stages from 70–100% of their personal best in the snatch. The load–velocity relationship was calculated using linear regression analysis to determine the velocity loss at 1st pull, transition, and 2nd pull. A group mean data contrast analysis revealed the highest load-dependent velocity loss for the 1st pull (t = 1.85, p = 0.044, g = 0.49 [−0.05, 1.04]) which confirmed our study hypothesis. In contrast to the group mean data, the individual athlete showed a unique response to increased loads during the acceleration sub-phases of the snatch. With the proposed method, individualized training recommendations on exercise selection and loading schemes can be derived to specifically improve the sub-phases of the snatch acceleration phase. Furthermore, the results highlight the importance of single-subject assessment when working with elite athletes in Olympic weightlifting.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 681
KW - biomechanics
KW - barbell velocity
KW - performance
KW - training
KW - load–velocity relationship
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-471599
SN - 1866-8364
IS - 681
ER -
TY - JOUR
A1 - Sandau, Ingo
A1 - Granacher, Urs
T1 - Effects of the barbell load on the acceleration phase during the snatch in elite Olympic weightlifting
JF - Sports
N2 - The load-depended loss of vertical barbell velocity at the end of the acceleration phase limits the maximum weight that can be lifted. Thus, the purpose of this study was to analyze how increased barbell loads affect the vertical barbell velocity in the sub-phases of the acceleration phase during the snatch. It was hypothesized that the load-dependent velocity loss at the end of the acceleration phase is primarily associated with a velocity loss during the 1st pull. For this purpose, 14 male elite weightlifters lifted seven load-stages from 70-100% of their personal best in the snatch. The load-velocity relationship was calculated using linear regression analysis to determine the velocity loss at 1st pull, transition, and 2nd pull. A group mean data contrast analysis revealed the highest load-dependent velocity loss for the 1st pull (t = 1.85, p = 0.044, g = 0.49 [-0.05, 1.04]) which confirmed our study hypothesis. In contrast to the group mean data, the individual athlete showed a unique response to increased loads during the acceleration sub-phases of the snatch. With the proposed method, individualized training recommendations on exercise selection and loading schemes can be derived to specifically improve the sub-phases of the snatch acceleration phase. Furthermore, the results highlight the importance of single-subject assessment when working with elite athletes in Olympic weightlifting.
KW - biomechanics
KW - barbell velocity
KW - performance
KW - training
KW - load-velocity
KW - relationship
Y1 - 2020
U6 - https://doi.org/10.3390/sports8050059
SN - 2075-4663
VL - 8
IS - 5
PB - MDPI
CY - Basel
ER -
TY - GEN
A1 - Granacher, Urs
A1 - Hortobágyi, Tibor
T1 - Exercise to improve mobility in healthy aging
T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 897
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-432419
SN - 1866-8372
IS - 897
ER -
TY - GEN
A1 - Pavillon, Thomas
A1 - Tourny, Claire
A1 - Ben Abderrahman, Abderraouf
A1 - Salhi, Iyed
A1 - Zouita, Sghaeir
A1 - Rouissi, Mehdi
A1 - Hackney, Anthony C.
A1 - Granacher, Urs
A1 - Zouhal, Hassane
T1 - Sprint and jump performances in highly trained young soccer players of different chronological age
BT - Effects of linear VS. CHANGE–OF–DIRECTION sprint training
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Objective
The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season.
Methods
Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance.
Results
For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post.
Conclusions
The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes’ performance development.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 697
KW - Football
KW - Repeated sprint
KW - Performance
KW - Speed
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-490557
SN - 1866-8364
IS - 697
ER -
TY - GEN
A1 - Hammami, Raouf
A1 - Chaabene, Helmi
A1 - Kharrat, Fatma
A1 - Werfelli, Hanen
A1 - Duncan, Michael
A1 - Rebai, Haithem
A1 - Granacher, Urs
T1 - Acute effects of different balance exercise types on selected measures of physical fitness in youth female volleyball players
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Background
Earlier studies have shown that balance training (BT) has the potential to induce performance enhancements in selected components of physical fitness (i.e., balance, muscle strength, power, speed). While there is ample evidence on the long-term effects of BT on components of physical fitness in youth, less is known on the short-term or acute effects of single BT sessions on selected measures of physical fitness.
Objective
To examine the acute effects of different balance exercise types on balance, change-of-direction (CoD) speed, and jump performance in youth female volleyball players.
Methods
Eleven female players aged 14 years participated in this study. Three types of balance exercises (i.e., anterior, posterolateral, rotational type) were conducted in randomized order. For each exercise, 3 sets including 5 repetitions were performed. Before and after the performance of the balance exercises, participants were tested for their static balance (center of pressure surface area [CoP SA] and velocity [CoP V]) on foam and firm surfaces, CoD speed (T-Half test), and vertical jump height (countermovement jump [CMJ] height). A 3 (condition: anterior, mediolateral, rotational balance exercise type) × 2 (time: pre, post) analysis of variance was computed with repeated measures on time.
Results
Findings showed no significant condition × time interactions for all outcome measures (p > 0.05). However, there were small main effects of time for CoP SA on firm and foam surfaces (both d = 0.38; all p < 0.05) with no effect for CoP V on both surface conditions (p > 0.05). For CoD speed, findings showed a large main effect of time (d = 0.91; p < 0.001). However, for CMJ height, no main effect of time was observed (p > 0.05).
Conclusions
Overall, our results indicated small-to-large changes in balance and CoD speed performances but not in CMJ height in youth female volleyball players, regardless of the balance exercise type. Accordingly, it is recommended to regularly integrate balance exercises before the performance of sport-specific training to optimize performance development in youth female volleyball players.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 713
KW - Postural stability
KW - Conditioning activity
KW - Short‐term effect
KW - Team sports
KW - Youth
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-517477
SN - 1866-8364
IS - 713
ER -
TY - JOUR
A1 - Hortobagyi, Tibor
A1 - Deak, Dorina
A1 - Farkas, Dora
A1 - Blenyesi, Eszter
A1 - Torok, Katalin
A1 - Granacher, Urs
A1 - Tollar, Jozsef
T1 - Effects of exercise dose and detraining duration on mobility at late midlife
BT - a randomized clinical trial
JF - Gerontology
N2 - Background:
Office workers near retirement tend to be sedentary and can be prone to mobility limitations and diseases. We examined the dose effects of exergaming volume and duration of detraining on motor and cognitive function in office workers at late midlife to reduce sedentariness and mobility limitations.
Methods:
In an assessor-blinded randomized trial, 160 workers aged 55-65 years performed physically active video games in a nonimmersive form of virtual reality (exergaming) in small, supervised groups for 1 h, 1x, 2x, or 3x/week for 8 weeks followed by detraining for 8 and 16 weeks. Exergaming comprises high-intensity, full-body sensorimotor coordination, balance, endurance, and strengthening exercises. The primary outcome was the 6-minute walk test (6MWT), and secondary outcomes were body mass, self-reported physical activity, sleep quality, Berg Balance Scale, Short Physical Performance Battery, fast gait speed, dynamic balance, heart rate recovery after step test, and 6 cognitive tests.
Results:
The 3 groups were not different in any of the outcomes at baseline (all p > 0.05). The outcomes were stable and had acceptable reliability (intraclass correlation coefficients >= 0.334) over an 8-week control period. Training produced an inverted U-shaped dose response of no (1x), most (2x), and medium (3x/week) effects of exergaming volume in most motor and selected cognitive outcomes. The distance walked in the 6MWT (primary outcome) increased most (94 m, 19%, p < 0.05), medium (57 m, 12%, p < 0.05), and least (4 m, 1%) after exergaming 2x, 3x, or 0x (control) (all different p < 0.05). The highest responders tended to retain the exercise effects over 8 weeks of detraining, independent of training volume. This maintenance effect was less consistent after 16 weeks of detraining.
Conclusion:
Less was more during training and lasted longer after detraining. A medium dose volume of exergaming produced the largest clinically meaningful improvements in mobility and selected cognitive tests in 60-year-old office workers with mild mobility limitations and intact cognition.
KW - exercise
KW - dose response
KW - walking capacity
KW - cognitive function
Y1 - 2021
U6 - https://doi.org/10.1159/000513505
SN - 0304-324X
SN - 1423-0003
VL - 67
IS - 4
SP - 403
EP - 414
PB - Karger
CY - Basel
ER -
TY - JOUR
A1 - Pavillon, Thomas
A1 - Tourny, Claire
A1 - Ben Abderrahman, Abderraouf
A1 - Salhi, Iyed
A1 - Zouita, Sghaeir
A1 - Rouissi, Mehdi
A1 - Hackney, Anthony C.
A1 - Granacher, Urs
A1 - Zouhal, Hassane
T1 - Sprint and jump performances in highly trained young soccer players of different chronological age
BT - Effects of linear VS. CHANGE–OF–DIRECTION sprint training
JF - Journal of Exercise Science & Fitness
N2 - Objective
The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season.
Methods
Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance.
Results
For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post.
Conclusions
The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes’ performance development.
KW - Football
KW - Repeated sprint
KW - Performance
KW - Speed
Y1 - 2020
U6 - https://doi.org/10.1016/j.jesf.2020.10.003
SN - 1728-869x
VL - 19
IS - 2
SP - 81
EP - 90
PB - Elsevier
CY - Singapore
ER -
TY - JOUR
A1 - Lesinski, Melanie
A1 - Prieske, Olaf
A1 - Chaabene, Helmi
A1 - Granacher, Urs
T1 - Seasonal effects of strength endurance vs. power training in young female soccer athletes
JF - Journal of strength and conditioning research : the research journal of the NSCA
N2 - Lesinski, M, Prieske, O, Chaabene, H, and Granacher, U. Seasonal effects of strength endurance vs. power training in young female soccer athletes. J Strength Cond Res 35(12S): S90-S96, 2021-This study examined the seasonal effects of strength endurance training (SET) vs. power training (PT) on physical fitness and body composition in young female soccer players. Thirty-six young female elite soccer players (15 +/- 1 years; maturity offset +3 +/- 1 years) were allocated to progressive SET (n = 19) or PT (n = 17). Over the course of one soccer season, SET performed slow movement velocity, moderate intensity (50-60% of the 1 repetition maximum [1RM]; 20-40 repetitions) strength exercises while PT performed moderate-to-high intensity (50-95% of the 1RM; 3-8 repetitions), high movement velocity strength exercises (2 sessions center dot wk(-1)). Before and after training, tests were performed for the assessment of muscle strength (1RM leg press), jump performance (countermovement jump [CMJ], drop jump [DJ]), muscular endurance (ventral Bourban test), linear speed (10 m, 20 m), change-of-direction (CoD) speed (T-test), dynamic balance (Y-balance test), sport-specific performance (kicking velocity), and body composition (lean body mass and fat mass). An analysis of covariance was used to test for between-group differences at post-test with baseline values as covariate. No significant between-group differences were observed in terms of total training volume over the respective soccer seasons (p = 0.069; d = 0.68). At post-test, SET showed significantly better ventral Bourban and T-test performances (d = 1.28-2.28; p = 0.000-0.001) compared with PT. However, PT resulted in significantly better 1RM leg press, DJ, 10-m, and 20-m sprint performances (d = 0.85-1.44; p = 0.000-0.026). No significant between-group differences were observed at post-test for CMJ, Y-balance test, kicking performance, and body composition (d = 0.20-0.74, p = 0.051-0.594). Our findings are mainly in accordance with the principle of training specificity. Both SET and PT are recommended to be implemented in young female elite soccer players according to the respective training period.
KW - strength training
KW - elite
KW - training specificity
KW - soccer players
KW - muscle
KW - endurance
KW - periodization
Y1 - 2021
U6 - https://doi.org/10.1519/JSC.0000000000003564
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - Supplement 12
SP - S90
EP - S96
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Jafarnezhadgero, Amir Ali
A1 - Anvari, Maryam
A1 - Granacher, Urs
T1 - Long-term effects of shoe mileage on ground reaction forces and lower limb muscle activities during walking in individuals with genu varus
JF - Clinical biomechanics
N2 - 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.
KW - footwear
KW - electromyography
KW - loading rate
KW - patients
Y1 - 2020
U6 - https://doi.org/10.1016/j.clinbiomech.2020.01.006
SN - 0268-0033
SN - 1879-1271
VL - 73
SP - 55
EP - 62
PB - Elsevier
CY - Oxford
ER -
TY - JOUR
A1 - Davies, Michael J.
A1 - Drury, Benjamin
A1 - Ramirez-Campillo, Rodrigo
A1 - Chaabene, Helmi
A1 - Moran, Jason
T1 - Effect of plyometric training and biological maturation on jump and change of direction ability in female youth
JF - Journal of strength and conditioning research : the research journal of the NSCA / National Strength & Conditioning Association
N2 - Biological maturation has been shown to affect male youths' responses to plyometric training (PT). However, to date, no researcher has examined the effect of maturation on the effects of PT in female youth. We undertook the first controlled intervention study to examine this, focusing on adaptive responses to countermovement jump (CMJ), reactive strength index (RSI), and change of direction (COD) performance in groups of female youth divided by maturation status (years from peak height velocity [PHV]). The training program lasted 7 weeks with subjects undertaking 2 sessions of PT per week. In the mid-PHV group, there was a small increase (effect size; 90% confidence interval = 0.40; -0.23 to 1.03) in CMJ performance. No changes were observed in the post-PHV group (0.02; -0.68 to 0.72). For RSI, there was a moderate increase in the mid-PHV group (0.94; 0.29-1.59) with only a trivial increase in the post-PHV group (0.06; -0.65 to 0.76). The intervention exerted no positive effect on COD performance in any group. Plyometric training seems to enhance CMJ and RSI in female youth, although the magnitude of adaptation could be affected by maturation status. A twice-per-week program of multidirectional jumping and hopping, with bilateral and unilateral components, can be used as a preparatory precursor to physical education classes or recreational sport.
KW - girls
KW - exercise
KW - sport
KW - athlete
Y1 - 2021
U6 - https://doi.org/10.1519/JSC.0000000000003216
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - 10
SP - 2690
EP - 2697
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Puschmann, Anne-Katrin
A1 - Lin, Chiao-I
A1 - Wippert, Pia-Maria
T1 - Sustainability of a motor control exercise intervention
BT - Analysis of long-term effects in a low back pain study
JF - Frontiers in sports and active living
N2 - Development of chronic pain after a low back pain episode is associated with increased pain sensitivity, altered pain processing mechanisms and the influence of psychosocial factors. Although there is some evidence that multimodal therapy (such as behavioral or motor control therapy) may be an important therapeutic strategy, its long-term effect on pain reduction and psychosocial load is still unclear. Prospective longitudinal designs providing information about the extent of such possible long-term effects are missing. This study aims to investigate the long-term effects of a homebased uni- and multidisciplinary motor control exercise program on low back pain intensity, disability and psychosocial variables. 14 months after completion of a multicenter study comparing uni- and multidisciplinary exercise interventions, a sample of one study center (n = 154) was assessed once more. Participants filled in questionnaires regarding their low back pain symptoms (characteristic pain intensity and related disability), stress and vital exhaustion (short version of the Maastricht Vital Exhaustion Questionnaire), anxiety and depression experiences (the Hospital and Anxiety Depression Scale), and pain-related cognitions (the Fear Avoidance Beliefs Questionnaire). Repeated measures mixed ANCOVAs were calculated to determine the long-term effects of the interventions on characteristic pain intensity and disability as well as on the psychosocial variables. Fifty four percent of the sub-sample responded to the questionnaires (n = 84). Longitudinal analyses revealed a significant long-term effect of the exercise intervention on pain disability. The multidisciplinary group missed statistical significance yet showed a medium sized long-term effect. The groups did not differ in their changes of the psychosocial variables of interest. There was evidence of long-term effects of the interventions on pain-related disability, but there was no effect on the other variables of interest. This may be partially explained by participant's low comorbidities at baseline. Results are important regarding costless homebased alternatives for back pain patients and prevention tasks. Furthermore, this study closes the gap of missing long-term effect analysis in this field.
KW - MiSpEx
KW - low back pain
KW - long-term effects
KW - multidisciplinary intervention
KW - sustainability
Y1 - 2021
U6 - https://doi.org/10.3389/fspor.2021.659982
SN - 2624-9367
VL - 3
SP - 1
EP - 8
PB - Frontiers Media
CY - Lausanne, Schweiz
ER -
TY - GEN
A1 - Appiah-Dwomoh, Edem Korkor
A1 - Müller, Steffen
A1 - Hadzic, Miralem
A1 - Mayer, Frank
T1 - Star Excursion Balance Test in young athletes with back pain
N2 - 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.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 337
KW - young athletes
KW - back pain
KW - star excursion balance test
Y1 - 2017
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400441
ER -
TY - GEN
A1 - De Souza Silveira, Raul
A1 - Carlsohn, Anja
A1 - Langen, Georg
A1 - Mayer, Frank
A1 - Scharhag-Rosenberger, Friederike
T1 - Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - 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.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 423
KW - peak fat oxidation
KW - reliability
KW - variability
KW - running
KW - treadmill ergometry
Y1 - 2018
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-407334
IS - 423
ER -
TY - THES
A1 - Müller, Steffen
T1 - Die belastungsspezifische neuromuskuläre Antwort bei Athleten mit Tendinopathie der Achilles- oder Patellarsehne : Analysen der funktionalen und therapeutischen Effekte eines sensomotorischen Trainings
T1 - Neuromuscular response to physical stress in athletes with tendinopathie of the achilles- or patellartendon : funktional and therapeutic effects of an sensorimotor training
N2 - Tendinopathien der Achilles- oder Patellarsehne sind häufig in Sportarten mit zahlreichen repetitiven Belastungen im Dehnungs-Verkürzungs-Zyklus der unteren Extremität zu finden. Sowohl eine möglicherweise alterierte belastungsspezifische neuromuskuläre Antwort (NMA), als auch funktional begründete Therapiemaßnahmen mit möglichen positiven Effekten sind aktuell ungeklärt. Ziel der Arbeit war deshalb die Untersuchung der belastungsspezifischen neuromuskulären Antwort bei Athleten mit Tendinopathie der Achilles- oder Patellarsehne im Vergleich zu beschwerdefreien Athleten. Zusätzlich sollten mögliche funktionale und therapeutische Effekte eines sensomotorischen Trainings im randomisierten, kontrollierten und prospektiven Studiendesign überprüft werden. 51 Sportler mit unilateraler Tendinopathie (Achilles-/Patellarsehne n = 35/16) und 33 gesunde Sportler wurden zur Beurteilung der belastungsspezifischen neuromuskulären Antwort eingeschlossen. Zur Klärung der Effekte eines sensomotorischen Trainings im Längsschnitt konnten 26 Sportler mit Tendinopathie randomisiert zu einer Kontrollgruppe (n = 14) und einer Therapiegruppe mit sensomotorischem Training (n = 12) zugeordnet werden. Nach einer ersten biomechanischen Messung M1 (Belastungssituationen: Lauf-, Stabilisations-, Kraftbelastung) und der Erhebung der subjektiven Schmerzsymptomatik folgte eine 8-wöchige Therapiephase mit einer abschließenden Re-Test-Messung M2 identisch zu M1. Das sensomotorische Training war auf die gesamte untere Extremität ausgerichtet und wurde nach Einweisung regelmäßig kontrolliert. Die Erfassung der NMA erfolgte über die Quantifizierung der muskulären Aktivität (EMG). Zusätzlich wurde die Kinetik (z.B. Maximalkraft) belastungsspezifisch erfasst. Eine reduzierte NMA konnte für die Sportler mit Tendinopathie über veränderte EMG-Zeit- und Amplitudenmessgrößen, eine reduzierte aktive Stabilisationsfähigkeit und Maximalkraft (p < 0,05) nachgewiesen werden. In Abhängigkeit der Lokalisation (Achilles-/Patellarsehen) bzw. der Seite (Beschwerdeseite/gesunde Seite) ergaben sich keine relevanten Differenzen. Das sensomotorische Training zeigte eine Optimierung der NMA (z.B. erhöhte Maximalkraft) bei Tendinopathie der Achilles- oder Patellarsehne. Die Überprüfung der Beschwerdesymptomatik wies in allen Schmerz-Scores nach der Therapie reduzierte Werte und damit einen positiven therapeutischen Effekt gegenüber der Kontrollgruppe auf. Zusammenfassend kann eine systematisch reduzierte NMA bei Lauf-, Stabilisations- und Kraftbelastung der Sportler mit Tendinopathie nachgewiesen werden. Das sensomotorische Training ist funktional und therapeutisch als effiziente Therapiemaßnahme zu erachten.
N2 - Tendinopathies of the achilles- or patellartendon are common overuse unjuries in sports including high numbers of repetitive stretch-shortening-cycles of the lower limb. Possible alterations of the neuromuscular response (NMR) to physical stress and functionally justified therapies with potential positive effects are currently unknown. The aim of the study was therefore the analysis of the neuromuscular response in situations with physical stress in athletes with tendinopathie of the achilles or patellartendon compared to symptom free athletes. In addition, possible functional and therapeutic effects of a sensorimotor training were studied in a prospective, randomized and controlled study. 51 athletes with unilateral tendinopathy (achilles-/patellartendon n = 35/16) and 33 healthy athletes were included to assess the stress related neuromuscular response (NMR). To clarify the effects of a sensorimotor training 26 athletes with tendinopathy were randomized to a control group (n = 14) and a therapy group with sensorimotor training (n = 12). After initial biomechanical measurements M1 (situations: running, active postural stability and maximum strength test) and the collection of subjective complaints (pain) an 8-week treatment phase followed with a final re-test M2 measure identical to M1. The sensorimotor training was arranged for the entire lower extremity, and was checked after an initial briefing on a regular basis. The assessment of the NMR was quantified by muscle activity (EMG). In addition, the kinetics (e.g. maximum force) was acquired in the stabilization and maximum strength test. A reduced NMR could be proven for athletes with tendinopathy with changed EMG time and amplitude measurements, a reduced active postural stabilization ability and reduced maximum strength (p <0.05). No relevant differences could be observed in comparing localization (achilles-/patellartendon) and side (leg with complains/healthy leg). The sensorimotor training showed an optimization of NMR (e.g. increased maximum strength) for patient with tendinopathy of the achilles- or patellartendon. The examination of the complaints showed reduced values in all pain scores after therapy. The treatment had therefore positive therapeutic effects compared to the control group. In summary, a systematically reduced NMR in running, stabilization and strength tests are evident for athletes with tendinopathy. The sensorimotor training can be considered as an efficient treatment with functional and therapeutic effects.
KW - Tendinopathie
KW - neuromuskuläre Kontrolle
KW - sensomotorisches Training
KW - Reliabilität
KW - tendinopathy
KW - neuromuscular control
KW - sensorimotor training
KW - reproducibility
Y1 - 2008
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16454
SN - 978-3-940793-18-8
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - GEN
A1 - Appiah-Dwomoh, Edem Korkor
A1 - Carlsohn, Anja
A1 - Mayer, Frank
T1 - Assessment of Dietary Intake of Long-Distance Race Car Drivers
BT - A Pilot Study
T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Long-distance race car drivers are classified as athletes. The sport is physically and mentally demanding, requiring long hours of practice. Therefore, optimal dietary intake is essential for health and performance of the athlete. The aim of the study was to evaluate dietary intake and to compare the data with dietary recommendations for athletes and for the general adult population according to the German Nutrition Society (DGE). A 24-h dietary recall during a competition preparation phase was obtained from 16 male race car drivers (28.3 ± 6.1 years, body mass index (BMI) of 22.9 ± 2.3 kg/m2). The mean intake of energy, nutrients, water and alcohol was recorded. The mean energy, vitamin B2, vitamin E, folate, fiber, calcium, water and alcohol intake were 2124 ± 814 kcal/day, 1.3 ± 0.5 mg/day, 12.5 ± 9.5 mg/day, 231.0 ± 90.9 ug/day, 21.4 ± 9.4 g/day, 1104 ± 764 mg/day, 3309 ± 1522 mL/day and 0.8 ± 2.5 mL/day respectively. Our study indicated that many of the nutrients studied, including energy and carbohydrate, were below the recommended dietary intake for both athletes and the DGE.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 482
KW - long-distance race car driving
KW - dietary intake
KW - 24 h recall
KW - pilot study
Y1 - 2018
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-419997
IS - 482
ER -
TY - JOUR
A1 - Hagoort, Iris
A1 - Vuillerme, Nicolas
A1 - Hortobágyi, Tibor
A1 - Lamoth, Claudine J. C.
T1 - Outcome-dependent effects of walking speed and age on quantitative and qualitative gait measures
JF - Gait & posture
N2 - Background: Walking speed predicts many clinical outcomes in old age. However, a comprehensive assessment of how walking speed affects accelerometer based quantitative and qualitative gait measures in younger and older adults is lacking. Research question: What is the relationship between walking speed and quantitative and qualitative gait outcomes in younger and older adults? Methods: Younger (n = 27, age: 21.6) and older participants (n = 27, age: 69.5) completed 340 steps on a treadmill at speeds of 0.70 to a maximum of 1.75 m.s(-1). We used generalized additive mixed models to determine the relationship between walking speed and quantitative (stride length, stride time, stride frequency and their variability) and qualitative (stride regularity, stability, smoothness, symmetry, synchronization, predictability) gait measures extracted from trunk accelerations. Results: The type of relationship between walking speed and the majority of gait measures (quantitative and qualitative) was characterized as logarithmic, with more prominent speed-effects at speeds below 1.20 m.s(-1). Changes in quantitative measures included shorter strides, longer stride times, and a lower stride frequency, with more variability at lower speeds independent of age. For qualitative measures, we found a decrease in gait symmetry, stability and regularity in all directions with decreasing speeds, a decrease in gait predictability (Vertical, V, anterior-posterior, AP) and stronger gait synchronization (AP-mediolateral, ML, AP-V), and direction dependent effects of gait smoothness, which decreased in V direction, but increased in AP and ML directions with decreasing speeds. We found outcome-dependent effects of age on the quantitative and qualitative gait measures, with either no differences between age-groups, age-related differences that existed regardless of speed, and age-related differences in the type of relationship with walking speed. Significance: The relationship between walking speed and quantitative and qualitative gait measures, and the effects of age on this relationship, depends on the type of gait measure studied.
KW - Gait quality and quantity
KW - Aging
KW - Walking speed
KW - Treadmill
KW - Generalized
KW - additive mixed models
Y1 - 2022
U6 - https://doi.org/10.1016/j.gaitpost.2022.01.001
SN - 0966-6362
SN - 1879-2219
VL - 93
SP - 39
EP - 46
PB - Elsevier
CY - Clare
ER -
TY - GEN
A1 - Quarmby, Andrew James
A1 - Mönnig, Jamal
A1 - Mugele, Hendrik
A1 - Henschke, Jakob
A1 - Kim, MyoungHwee
A1 - Cassel, Michael
A1 - Engel, Tilman
T1 - Biomechanics and lower limb function are altered in athletes and runners with achilles tendinopathy compared with healthy controls: A systematic review
T2 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe
N2 - Achilles tendinopathy (AT) is a debilitating injury in athletes, especially for those engaged in repetitive stretch-shortening cycle activities. Clinical risk factors are numerous, but it has been suggested that altered biomechanics might be associated with AT. No systematic review has been conducted investigating these biomechanical alterations in specifically athletic populations. Therefore, the aim of this systematic review was to compare the lower-limb biomechanics of athletes with AT to athletically matched asymptomatic controls. Databases were searched for relevant studies investigating biomechanics during gait activities and other motor tasks such as hopping, isolated strength tasks, and reflex responses. Inclusion criteria for studies were an AT diagnosis in at least one group, cross-sectional or prospective data, at least one outcome comparing biomechanical data between an AT and healthy group, and athletic populations. Studies were excluded if patients had Achilles tendon rupture/surgery, participants reported injuries other than AT, and when only within-subject data was available.. Effect sizes (Cohen's d) with 95% confidence intervals were calculated for relevant outcomes. The initial search yielded 4,442 studies. After screening, twenty studies (775 total participants) were synthesised, reporting on a wide range of biomechanical outcomes. Females were under-represented and patients in the AT group were three years older on average. Biomechanical alterations were identified in some studies during running, hopping, jumping, strength tasks and reflex activity. Equally, several biomechanical variables studied were not associated with AT in included studies, indicating a conflicting picture. Kinematics in AT patients appeared to be altered in the lower limb, potentially indicating a pattern of “medial collapse”. Muscular activity of the calf and hips was different between groups, whereby AT patients exhibited greater calf electromyographic amplitudes despite lower plantar flexor strength. Overall, dynamic maximal strength of the plantar flexors, and isometric strength of the hips might be reduced in the AT group. This systematic review reports on several biomechanical alterations in athletes with AT. With further research, these factors could potentially form treatment targets for clinicians, although clinical approaches should take other contributing health factors into account. The studies included were of low quality, and currently no solid conclusions can be drawn.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 830
KW - achilles tendinopathy
KW - biomechanics
KW - neuromuscular
KW - kinetics
KW - electromyography
KW - athletes
KW - runners
KW - kinematics
Y1 - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-587603
SN - 1866-8364
IS - 830
ER -
TY - JOUR
A1 - Quarmby, Andrew James
A1 - Mönnig, Jamal
A1 - Mugele, Hendrik
A1 - Henschke, Jakob
A1 - Kim, MyoungHwee
A1 - Cassel, Michael
A1 - Engel, Tilman
T1 - Biomechanics and lower limb function are altered in athletes and runners with achilles tendinopathy compared with healthy controls: A systematic review
JF - Frontiers in Sports and Active Living
N2 - Achilles tendinopathy (AT) is a debilitating injury in athletes, especially for those engaged in repetitive stretch-shortening cycle activities. Clinical risk factors are numerous, but it has been suggested that altered biomechanics might be associated with AT. No systematic review has been conducted investigating these biomechanical alterations in specifically athletic populations. Therefore, the aim of this systematic review was to compare the lower-limb biomechanics of athletes with AT to athletically matched asymptomatic controls. Databases were searched for relevant studies investigating biomechanics during gait activities and other motor tasks such as hopping, isolated strength tasks, and reflex responses. Inclusion criteria for studies were an AT diagnosis in at least one group, cross-sectional or prospective data, at least one outcome comparing biomechanical data between an AT and healthy group, and athletic populations. Studies were excluded if patients had Achilles tendon rupture/surgery, participants reported injuries other than AT, and when only within-subject data was available.. Effect sizes (Cohen's d) with 95% confidence intervals were calculated for relevant outcomes. The initial search yielded 4,442 studies. After screening, twenty studies (775 total participants) were synthesised, reporting on a wide range of biomechanical outcomes. Females were under-represented and patients in the AT group were three years older on average. Biomechanical alterations were identified in some studies during running, hopping, jumping, strength tasks and reflex activity. Equally, several biomechanical variables studied were not associated with AT in included studies, indicating a conflicting picture. Kinematics in AT patients appeared to be altered in the lower limb, potentially indicating a pattern of “medial collapse”. Muscular activity of the calf and hips was different between groups, whereby AT patients exhibited greater calf electromyographic amplitudes despite lower plantar flexor strength. Overall, dynamic maximal strength of the plantar flexors, and isometric strength of the hips might be reduced in the AT group. This systematic review reports on several biomechanical alterations in athletes with AT. With further research, these factors could potentially form treatment targets for clinicians, although clinical approaches should take other contributing health factors into account. The studies included were of low quality, and currently no solid conclusions can be drawn.
KW - achilles tendinopathy
KW - biomechanics
KW - neuromuscular
KW - kinetics
KW - electromyography
KW - athletes
KW - runners
KW - kinematics
Y1 - 2023
U6 - https://doi.org/10.3389/fspor.2022.1012471
SN - 2624-9367
PB - Frontiers
CY - Lausanne, Schweiz
ER -
TY - THES
A1 - Chan, Yuan-Shuo
T1 - Zum Zusammenhang zwischen posturaler Balance und kognitiven bzw. somatischen Faktoren
T1 - The correlation between postural balance and cognitive/ somatic factors
N2 - Balance ist als die koordinative Fähigkeit anzusehen, die am meisten durch das Sinnes- und Nervensystem determiniert ist. Damit könnte sie als Indikator für Funktionseinschränkungen des Nervensystems - etwa bei Lernstörungen - von Wert sein. Aussagen über Zusammenhänge zwischen Balance und Kognition werden vielfach diskutiert, sind jedoch noch nicht hinreichend wissenschaftlich gesichert. Hieraus wird die zentrale Zielstellung der Arbeit abgeleitet, das Wissen über somatische und psychische Determinanten von Balance zu erweitern. Betrachtet werden daher bei Vorschulkindern mögliche Zusammenhänge mit dem Geschlecht, mit den anthropometrischen Parametern Körperhöhe und Fußgröße, mit Statikstörungen des Beckens und der Intelligenzleistung. An der Studie nahmen insgesamt 201 drei- bzw. vierjährige Kinder sowie 148 fünf- bzw. sechsjährige Kinder teil. Die Balancefähigkeit wurde mit Hilfe einer Kraftmomentenplattform sowie eines klinischen Tests erfasst und mit anthropometrischen Parametern, qualitativen statischen Befunden bzw. den Ergebnissen des BIVA-Intelligenztests nach SCHAARSCHMIDT verglichen. Für die Auswertung der Balanceparameter wurden sowohl lineare als auch nichtlineare Verfahren eingesetzt, die zum Teil gegenläufige Trends in Bezug auf Zusammenhänge lieferten. Im Ergebnis konnte ein starker Einfluss des Geschlechts nachgewiesen werden. Mädchen zeigten eine bessere Balanceleistung als Jungen sowohl bei 3-Jährigen als auch bei 6-Jährigen. Dies wird als Beleg für den geschlechtsspezifischen Vorsprung der sensomotorischen Entwicklung bei den Mädchen im Alter von 3 bis 6 Jahren angesehen. Außerdem gab es einige Hinweise auf einen Zusammenhang mit der Körperhöhe bzw. Fußlänge. Ein Zusammenhang mit den Umstellungen des ersten Gestaltwandels wird vermutet. Die Daten sprechen für einen statistisch schwachen Einfluss von Störungen der Beckenstatik (Beckenverwringung) auf die Balance bei den Kindern. Es wird vermutet, dass die Verrechnung Balance relevanter Inputs durch nozizeptive Impulse beeinträchtig werden kann. Dies könnte Anlass sein, diesen Aspekt bei Funktionsstörungen mit zu berücksichtigen. Signifikante Zusammenhänge mit Ergebnissen des BIVA-Intelligenztests konnten kaum gefunden werden. Allerdings fallen überzufällig viele Mittelwertvergleiche in Richtung der Hypothese aus, erreichen jedoch nicht Signifikanzniveau. Dies könnte ein Hinweis auf einen schwachen Zusammenhang darstellen, der jedoch mit einer größeren Gruppe noch bestätigt werden müsste. Weitere Forschung auf diesem Gebiet ist erforderlich. Sollte hinreichende Evidenz erreicht werden können, so könnte in der Förderung koordinativer Fähigkeiten und insbesondere der posturalen Balance eine wichtige pädagogische Reserve liegen.
N2 - Balance is considered a coordinative ability, which is mostly affected by the sensory and nervous systems. It can be used as an indicator for the functional ability of the nervous system, such as learning disability. Although the relationship between balance and cognition has long been postulated, this interaction has not yet been scientifically well established. The aim of this study is to examine the somatic and psychological determinants of balance. Preschool children were used to analyse the balance-cognition relationship with respect to gender, anthropometric parameters of body height and foot length, pelvic static and intelligence ability. 201 three to four years old children, as well as 148 five to six years old children, were used in this study. A clinical test involving a force moment platform was used to examine the balance ability. Results obtained were compared with specific anthropometric parameters and findings obtained from the BIVA-intelligent tests (SCHAARSCHMIDT). In the results, there is a strong effect of gender on balance. Girls showed a better balance ability than boys in the age groups of three and six years old. This finding provides evidence of an earlier gender specific advantage of sensor-motor development in girls between the ages of 3 to 6 years old. A relationship between postural balance and body height/ foot length was found. This may be attributed to the transposition of the body developmental changes. The results show a weak statistical effect of pelvic static disorders on balance in children. It can be suggested that inputs through the nociceptive impulse pathway can have a negative effect on balance. This can be factored as an aspect of a function disorder. Slight significant relationship could be found from the results of BIVA-intelligent tests. This can provide information on the weak relationship, which might show in larger group size. Further studies in this research area are necessary. Sufficient evidence should be reached, regarding the support of coordination ability and particularly postural balance, and the relationship could play an important role in education
KW - Sensomotorik
KW - Gleichgewicht
KW - Intelligenz
KW - Balance
KW - Kind
KW - Kognition
KW - Somatik
KW - balance
KW - cognition
KW - sensorimotor function
KW - child
Y1 - 2006
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-10237
ER -
TY - JOUR
A1 - Behrens, Martin
A1 - Gube, Martin
A1 - Chaabene, Helmi
A1 - Prieske, Olaf
A1 - Zenon, Alexandre
A1 - Broscheid, Kim-Charline
A1 - Schega, Lutz
A1 - Husmann, Florian
A1 - Weippert, Matthias
T1 - Fatigue and human performance
BT - an updated framework
JF - Sports medicine : an international journal of applied medicine and science in sport and exercise
N2 - Fatigue has been defined differently in the literature depending on the field of research. The inconsistent use of the term fatigue complicated scientific communication, thereby limiting progress towards a more in-depth understanding of the phenomenon. Therefore, Enoka and Duchateau (Med Sci Sports Exerc 48:2228-38, 2016, [3]) proposed a fatigue framework that distinguishes between trait fatigue (i.e., fatigue experienced by an individual over a longer period of time) and motor or cognitive task-induced state fatigue (i.e., self-reported disabling symptom derived from the two interdependent attributes performance fatigability and perceived fatigability). Thereby, performance fatigability describes a decrease in an objective performance measure, while perceived fatigability refers to the sensations that regulate the integrity of the performer. Although this framework served as a good starting point to unravel the psychophysiology of fatigue, several important aspects were not included and the interdependence of the mechanisms driving performance fatigability and perceived fatigability were not comprehensively discussed. Therefore, the present narrative review aimed to (1) update the fatigue framework suggested by Enoka and Duchateau (Med Sci Sports Exerc 48:2228-38, 2016, [3]) pertaining the taxonomy (i.e., cognitive performance fatigue and perceived cognitive fatigue were added) and important determinants that were not considered previously (e.g., effort perception, affective valence, self-regulation), (2) discuss the mechanisms underlying performance fatigue and perceived fatigue in response to motor and cognitive tasks as well as their interdependence, and (3) provide recommendations for future research on these interactions. We propose to define motor or cognitive task-induced state fatigue as a psychophysiological condition characterized by a decrease in motor or cognitive performance (i.e., motor or cognitive performance fatigue, respectively) and/or an increased perception of fatigue (i.e., perceived motor or cognitive fatigue). These dimensions are interdependent, hinge on different determinants, and depend on body homeostasis (e.g., wakefulness, core temperature) as well as several modulating factors (e.g., age, sex, diseases, characteristics of the motor or cognitive task). Consequently, there is no single factor primarily determining performance fatigue and perceived fatigue in response to motor or cognitive tasks. Instead, the relative weight of each determinant and their interaction are modulated by several factors.
Y1 - 2022
U6 - https://doi.org/10.1007/s40279-022-01748-2
SN - 0112-1642
SN - 1179-2035
VL - 53
IS - 1
SP - 7
EP - 31
PB - Springer
CY - Heidelberg
ER -
TY - THES
A1 - Stamm, Raini
T1 - Significance of the anthropometric factor in young female volleyballers´ physical abilities, technical skills, psychophysiological properties and performance in the game
T1 - Bedeutung des anthropometrischen Faktors bei der körperlichen Fähigkeiten, volleyballtechnischen Geschicklichkeiten, psychophysiologischen Eigenschaften und Spielleistung
N2 - Aim The aim of the present study was to examine young female volleyballers’ body build, physical abilities, technical skills and psychophysiological properties in relation to their performance at competitions. The sample consisted of 46 female volleyballers aged 13-16 years. 49 basic anthropometric measurements were measured and 65 proportions and body composition characteristics were calculated. 9 physical ability tests, 9 volleyball technical skills tests and 21 psychophysiological tests were carried out. The game performance was recorded by the computer program Game. The program enabled to fix the performance of technical elements in case of each player. The computer program Game calculated the index of proficiency in case of each girl for each element. The first control group consisted of 74 female volleyballers aged 13–15 years with whom reduced anthropometry was provided and 28 games were recorded. The second control group consisted of 586 ordinary schoolgirls aged 13–16 years with whom full anthropometry was provided. Results In order to systematize all anthropometric characteristics, we first studied the essence of the anthropometric structure of the body as a whole. It turned out to be a characteristic system where all variables are in significant correlation between one another and where the leading characteristics are height and weight. Therefore we based the classification on the mean height and weight of the whole sample. We formed a 5 class SD classification. There are three classes of concordance between height and weight: small height – small weight, medium height – medium height, big height – big weight. The other two classes were classes of disconcordance between height and weight- pycnomorphs and leptomorphs. We managed to show that gradual increase in height and weight brought about statistically significant increase in length, breadth and depth measurements, circumferences, bone thicknesses and skinfolds. There were also systematic changes in indeces and body composition characteristics. Pycnomorphs and leptomorphs also showed differences specific to their body types in body measurements and body composition. The results of all tests were submitted to basic statistical analysis and all correlations were found between all the tests (volleyball technical skills, psychophysiological abilities, physical abilities), and all basic anthropometric variables (n = 49) and all proportions and body composition characteristics (n = 65). All anthropometric measurements and test results were correlated with the index of proficiency for all elements of the game. The best linear regression models were calculated for predicting proficiency in different elements of the game. We can see that body build and all kind of tests took part in predicting the proficiency of the game. The most essential for performing attack, block and feint were anthropometric and psychophysiological models. The studied complex of body build characteristics and tests results determine the players’ proficiency at competitions, are an important tool for testing the player’s individual development, enable to choose volleyballers from among schoolgirls and represent the whole body constitutional model of a young female volleyballer. Outlook Our outlook for the future is to continue recording of all Estonian championship games with the computer program Game, to continue the players’ anthropometric measuring and psychophysiological testing at competitions and to compile a national register for assessment of development of individual players and teams.
N2 - Ziel Das Ziel dieser Untersuchung war den Körperbau, die körperliche Fähigkeiten, die technische Geschicklichkeiten und psychophysiologische Fähigkeiten der jungen Volleyballspielerinnen in Bezug auf ihre Leistung bei den Wettkämpfen zu untersuchen. Die Auswahl bestand aus 46 Volleyballspielerinnen im Alter 13-16 Jahren. Es wurden 49 anthropometrische Masse gemessen, 65 Proportionen und Körperbaumerkmale kalkuliert, 9 Tests der physischen Fähigkeit und 9 Testen der volleyballtechnischen Geschicken ausgeführt. Die Spielleistung wurde mit dem Computerprogramm Game gespeichert. Das Programm machte es möglich, die Leistung der technischen Elementen im Falle von jeder Spielerinnen zu bestimmen. Das Computerprogramm Game kalkulierte den Leistungsindex im Falle von jedem Mädchen für jedes Element. Die erste Kontrollgruppe bestand von 74 Volleyballspielerinnen im Alter von 13–15 Jahren, mit wem reduzierte Anthropometrie durchgeführt wurde und 28 Spiele gespeichert wurden. Die andere Kontrollgruppe bestand aus 586 gewöhnliche Schulmädchen im Alter von 13–16 Jahren, mit wem volle Anthropometrie durchgeführt wurde. Ergebnisse Um alle anthropometrische Merkmale zu systematisieren, haben wir zunächst das Wesen der anthropometrischen Struktur des Körpers als Ganzes geforscht. Es hat sich erwiesen, dass es um einem characteristischen System handelt, bei dem alle Merkmale in aussagekräftiger Beziehung miteinander sind und die führende Merkmale die Höhe und das Gewicht sind. Darum haben wir die Klassifikation auf die durchschnittliche Höhe und das durchschnittliche Gewicht der ganzen Auswahl gegründet. Wir haben eine Klass 5 SD Klassifikation gebildet. Es gibt drei Übereinstimmungsklassen zwischen Höhe und Gewicht: kleine Höhe – kleines Gewicht, mittlere Höhe – mittleres Gewicht, grosse Höhe – grosses Gewicht. Die andere zwei Klassen waren die Nichtübereinstimmungsklassen zwischen Höhe und Gewicht - Pyknomorphe und Leptomorphe. Es ist uns gelungen, zu beweisen, dass der stufenartige Anstieg in der Höhe und in dem Gewicht einen statistisch bedeutsamen Anstieg in den Merkmalen der Länge, Breite und Tiefe, in den Umkreisen, in den Dicken des Knochens und in den Hautfalten veranlassen. Es bestanden auch systematische Änderungen in den Indexen und Körperbaumerkmalen. Auch die Pyknomorphen und Leptomorphen zeigten Unterschiede für ihre Körpermasse und Körperbau spezifische Unterschiede. Die Ergebnisse von allen Testen wurden der statistischen Grundanalyse unterworfen und alle Korrelationen zwischen allen Testen (volleyballtechnische Geschicke, psychophysiologische Fähigkeiten, physische Fähigkeiten) und allen anthropometrischen Grundvariablen (n = 49) und allen Proportionen und Körperbaumerkmalen (n = 65) gefunden. Alle anthropometrische Merkmale und Testresultaten wurden im Falle von allen Spielelementen mit dem Leistungsindex korreliert. Die besten lineare Regressionmodellen, um die Leistung in verschiedenen Spielelementen vorauszusagen, wurden kalkuliert. Es ist sichtbar, dass der Körperbau und alle Testarten in der Voraussage der Spielleistung mitgemacht haben. Das Wichtigste um einen Angriff, einen Block und eine Finte durchzuführen, waren anthropometrische und psychophysiologische Modelle. Der geforschte Komplex der Körperbaumerkmalen und der Testergebnissen bestimmen die Leistung der Spielerin in den Wettbewerben, sind ein wichtiges Mittel für das Testen der individuellen Entwicklung der Spielerin, ermöglichen die Volleyballspielerinnen aus den Schulmädchen zu wählen und vertreten das ganze Körperbaumodell einer jungen Volleyballspielerin. Die Aussicht Unsere Aussicht für die Zukunft ist, das Speichern von allen Spielen der estnischen Meisterschaftswettbewerben mit dem Computerprogramm Game, die anthropometrische Messung und das psychophysiologisches Testen der Spielerinnen während Wettbewerben fortzusetzen und ein staatliches Register für die Bewertung der Entwicklung der individuellen Spielerinnen und Teamen zusammenzustellen.
KW - Anthropometrie
KW - Jugendliche
KW - Testen
KW - Volleyball
KW - Spielleistung
KW - anthropometry
KW - adolescents
KW - testing
KW - volleyball
KW - performance
Y1 - 2007
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-13005
ER -
TY - JOUR
A1 - Chaabene, Helmi
A1 - Negra, Yassine
A1 - Moran, Jason
A1 - Prieske, Olaf
A1 - Sammoud, Senda
A1 - Ramirez-Campillo, Rodrigo
A1 - Granacher, Urs
T1 - Plyometric training improves not only measures of linear speed, power, and change-of-direction speed but also repeated sprint ability in young female handball players
JF - Journal of strength and conditioning research : the research journal of the NSCA
N2 - This study examined the effects of an 8-week plyometric training (PT) program on components of physical fitness in young female handball players. Twenty-one female adolescent handball players were assigned to an experimental group (EG, n = 12; age = 15.9 +/- 0.2 years) or an active control group (CG, n = 9, age = 15.9 +/- 0.3 years). While EG performed plyometric exercises in replacement of some handball-specific drills, CG maintained the regular training schedule. Baseline and follow-up tests were performed for the assessment of linear speed (i.e., 5-, 10-, and 20-m time), change-of-direction (CoD) speed (i.e., T-test time), muscle power (i.e., countermovement jump [CMJ] height and reactive strength index [RSI]), and repeated sprint ability (RSA) (RSA total time [RSA(total)], RSA best time [RSA(best)], and RSA fatigue index [RSA(FI)]). Data were analyzed using magnitude-based inferences. Within-group analyses for the EG revealed moderate-to-large improvements for the 5-m (effect size [ES] = 0.81 [0.1-1.5]), 10-m sprint time (ES = 0.84 [0.1-1.5]), RSI (ES = 0.75 [0.1-1.4]), RSA(FI) (ES = 0.65 [0.0-1.3]), and T-test time (ES = 1.46 [0.7-2.2]). Trivial-to-small ES was observed for RSA(best) (ES = 0.18 [-0.5 to 0.9]), RSA(total) (ES = 0.45 [-0.2 to 1.1]), 20-m sprint time (ES = 0.56 [-0.1 to 1.2]), and CMJ height (ES = 0.57 [-0.1 to 1.3]). For the CG, within-group analyses showed a moderate performance decline for T-test time (ES = -0.71 [-1.5 to 0.1]), small decreases for 5-m sprint time (ES = -0.46 [-1.2 to 0.3]), and a trivial decline for 10-m (ES = -0.10 [-0.9 to 0.7]) and 20-m sprint times (ES = -0.16 [-0.9 to 0.6]), RSA(total) (ES = 0.0 [-0.8 to 0.8]), and RSA(best) (ES = -0.20 [-0.9 to 0.6]). The control group achieved trivial-to-small improvements for CMJ height (ES = 0.10 [-0.68 to 0.87]) and RSI (ES = 0.30 [-0.5 to 1.1]). In conclusion, a short-term in-season PT program, in replacement of handball-specific drills, is effective in improving measures of physical fitness (i.e., linear/CoD speed, jumping, and RSA) in young female handball players.
KW - stretch-shortening cycle
KW - physical fitness
KW - young athletes
Y1 - 2021
U6 - https://doi.org/10.1519/JSC.0000000000003128
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - 8
SP - 2230
EP - 2235
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Quarmby, Andrew James
A1 - Khajooei, Mina
A1 - Engel, Tilman
A1 - Kaplick, Hannes
A1 - Mayer, Frank
T1 - The feasibility of a split-belt instrumented treadmill running protocol with perturbations
JF - Journal of biomechanics
N2 - 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.
KW - Lower-extremity perturbations
KW - Split-belt treadmill
KW - Running
KW - Stumbling
KW - EMC
Y1 - 2020
U6 - https://doi.org/10.1016/j.jbiomech.2019.109493
SN - 0021-9290
SN - 1873-2380
VL - 98
PB - Elsevier
CY - Oxford
ER -
TY - JOUR
A1 - Schomöller, Anne
A1 - Schugardt, Monique
A1 - Kotsch, Peggy
A1 - Mayer, Frank
T1 - The effect of body composition on cycling power during an incremental test in young athletes
JF - Journal of strength and conditioning research : the research journal of the NSCA / National Strength & Conditioning Association
N2 - 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.
KW - youth competitive sport
KW - body fat
KW - fat-free mass
KW - cycling performance
Y1 - 2020
U6 - https://doi.org/10.1519/JSC.0000000000003271
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - 11
SP - 3225
EP - 3231
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Henschke, Jakob
A1 - Zecher, Mahli Megan
A1 - Mayer, Frank
A1 - Engel, Tilman
T1 - Contralateral repeated bout effect following preconditioning exercises
BT - a systematic review
JF - Sport sciences for health
N2 - Background Recent studies indicate the existence of a repeated bout effect on the contralateral untrained limb following eccentric and isometric contractions. Aims This review aims to summarize the evidence for magnitude, duration and differences of this effect following isometric and eccentric preconditioning exercises. Methods Medline, Cochrane, and Web of science were searched from January 1971 until September 2020. Randomized controlled trials, case-control studies and cross-sectional studies were identified by combining keywords and synonyms (e.g., "contralateral", "exercise", "preconditioning", "protective effect"). At least two of the following outcome parameters were mandatory for study inclusion: strength, muscle soreness, muscle swelling, limb circumference, inflammatory blood markers or protective index (relative change of aforementioned measures). Results After identifying 1979 articles, 13 studies were included. Most investigations examined elbow flexors and utilized eccentric isokinetic protocols to induce the contralateral repeated bout effect. The magnitude of protection was observed in four studies, smaller values of the contralateral when compared to the ipsilateral repeated bout effect were noted in three studies. The potential mechanism is thought to be of neural central nature since no differences in peripheral muscle activity were observed. Time course was examined in three investigations. One study showed a smaller protective effect following isometric preconditioning when compared to eccentric preconditioning exercises. Conclusions The contralateral repeated bout effect demonstrates a smaller magnitude and lasts shorter than the ipsilateral repeated bout effect. Future research should incorporate long-term controlled trials including larger populations to identify central mechanisms. This knowledge should be used in clinical practice to prepare immobilized limbs prospectively for an incremental load.
KW - musculoskeletal physiological phenomena
KW - muscle damage
KW - adaptation
KW - Crossover
KW - muscle soreness
KW - isometric contraction
Y1 - 2021
U6 - https://doi.org/10.1007/s11332-021-00804-0
SN - 1824-7490
SN - 1825-1234
VL - 18
IS - 1
SP - 1
EP - 10
PB - Soringer Italia
CY - Milan
ER -
TY - JOUR
A1 - Appiah-Dwomoh, Edem Korkor
A1 - Carlsohn, Anja
A1 - Mayer, Frank
T1 - Assessment of Dietary Intake of Long-Distance Race Car Drivers
BT - A Pilot Study
JF - Sports
N2 - Long-distance race car drivers are classified as athletes. The sport is physically and mentally demanding, requiring long hours of practice. Therefore, optimal dietary intake is essential for health and performance of the athlete. The aim of the study was to evaluate dietary intake and to compare the data with dietary recommendations for athletes and for the general adult population according to the German Nutrition Society (DGE). A 24-h dietary recall during a competition preparation phase was obtained from 16 male race car drivers (28.3 ± 6.1 years, body mass index (BMI) of 22.9 ± 2.3 kg/m2). The mean intake of energy, nutrients, water and alcohol was recorded. The mean energy, vitamin B2, vitamin E, folate, fiber, calcium, water and alcohol intake were 2124 ± 814 kcal/day, 1.3 ± 0.5 mg/day, 12.5 ± 9.5 mg/day, 231.0 ± 90.9 ug/day, 21.4 ± 9.4 g/day, 1104 ± 764 mg/day, 3309 ± 1522 mL/day and 0.8 ± 2.5 mL/day respectively. Our study indicated that many of the nutrients studied, including energy and carbohydrate, were below the recommended dietary intake for both athletes and the DGE.
KW - long-distance race car driving
KW - dietary intake
KW - 24 h recall
KW - pilot study
Y1 - 2018
U6 - https://doi.org/10.3390/sports6040118
SN - 2075-4663
VL - 6
IS - 4
SP - 1
EP - 7
PB - MDPI
CY - Basel
ER -
TY - GEN
A1 - Hirschmueller, Anja
A1 - Baur, Heiner
A1 - Braun, Sepp
A1 - Kreuz, Peter C.
A1 - Suedkamp, Norbert P
A1 - Niemeyer, Philipp
T1 - Rehabilitation after autologous chondrocyte implantation for isolated cartilage defects of the knee
N2 - Autologous chondrocyte implantation for treatment of isolated cartilage defects of the knee has become well established. Although various publications report technical modifications, clinical results, and cell-related issues, little is known about appropriate and optimal rehabilitation after autologous chondrocyte implantation. This article reviews the literature on rehabilitation after autologous chondrocyte implantation and presents a rehabilitation protocol that has been developed considering the best available evidence and has been successfully used for several years in a large number of patients who underwent autologous chondrocyte implantation for cartilage defects of the knee.
T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 367
KW - autologous chondrocyte implantation
KW - cartilage repair
KW - cartilage defect
KW - cell transplantation
KW - knee joint
KW - rehabilitation
Y1 - 2017
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-403170
ER -
TY - JOUR
A1 - Herold, Fabian
A1 - Theobald, Paula
A1 - Gronwald, Thomas
A1 - Rapp, Michael A.
A1 - Müller, Notger Germar
T1 - Going digital – a commentary on the terminology used at the intersection of physical activity and digital health
JF - European review of aging and physical activity
N2 - In recent years digital technologies have become a major means for providing health-related services and this trend was strongly reinforced by the current Coronavirus disease 2019 (COVID-19) pandemic. As it is well-known that regular physical activity has positive effects on individual physical and mental health and thus is an important prerequisite for healthy aging, digital technologies are also increasingly used to promote unstructured and structured forms of physical activity. However, in the course of this development, several terms (e.g., Digital Health, Electronic Health, Mobile Health, Telehealth, Telemedicine, and Telerehabilitation) have been introduced to refer to the application of digital technologies to provide health-related services such as physical interventions. Unfortunately, the above-mentioned terms are often used in several different ways, but also relatively interchangeably. Given that ambiguous terminology is a major source of difficulty in scientific communication which can impede the progress of theoretical and empirical research, this article aims to make the reader aware of the subtle differences between the relevant terms which are applied at the intersection of physical activity and Digital Health and to provide state-of-art definitions for them.
KW - Digital Health
KW - Electronic Health
KW - Mobile Health
KW - Telehealth
KW - Telemedicine
KW - Physical activity
KW - Physical training
KW - Aging
Y1 - 2022
U6 - https://doi.org/10.1186/s11556-022-00296-y
SN - 1861-6909
VL - 19
PB - Springer
CY - Berlin ; Heidelberg
ER -
TY - JOUR
A1 - Teich, Paula
A1 - Fühner, Thea Heidi
A1 - Baehr, Florian
A1 - Puta, Christian
A1 - Granacher, Urs
A1 - Kliegl, Reinhold
T1 - Covid pandemic effects on the physical fitness of primary school children
BT - results of the german EMOTIKON project
JF - Sports Medicine - Open
N2 - BackgroundIn spring of 2020, the Sars-CoV-2 incidence rate increased rapidly in Germany and around the world. Throughout the next 2 years, schools were temporarily closed and social distancing measures were put in place to slow the spread of the Covid-19 virus. Did these social restrictions and temporary school lockdowns affect children's physical fitness? The EMOTIKON project annually tests the physical fitness of all third-graders in the Federal State of Brandenburg, Germany. The tests assess cardiorespiratory endurance (6-min-run test), coordination (star-run test), speed (20-m sprint test), lower (powerLOW, standing long jump test), and upper (powerUP, ball-push test) limbs muscle power, and static balance (one-legged stance test with eyes closed). A total of 125,893 children were tested in the falls from 2016 to 2022. Primary analyses focused on 98,510 keyage third-graders (i.e., school enrollment according to the legal key date, aged 8 to 9 years) from 515 schools. Secondary analyses included 27,383 older-than-keyage third-graders (i.e., OTK, delayed school enrollment or repetition of a grade, aged 9 to 10 years), who have been shown to exhibit lower physical fitness than expected for their age. Linear mixed models fitted pre-pandemic quadratic secular trends, and took into account differences between children and schools.ResultsThird-graders exhibited lower cardiorespiratory endurance, coordination, speed and powerUP in the Covid pandemic cohorts (2020-2022) compared to the pre-pandemic cohorts (2016-2019). Children's powerLOW and static balance were higher in the pandemic cohorts compared to the pre-pandemic cohorts. From 2020 to 2021, coordination, powerLOW and powerUP further declined. Evidence for some post-pandemic physical fitness catch-up was restricted to powerUP. Cohen's |ds| for comparisons of the pandemic cohorts 2020-2022 with pre-pandemic cohorts 2016-2019 ranged from 0.02 for powerLOW to 0.15 for coordination. Within the pandemic cohorts, keyage children exhibited developmental losses ranging from approximately 1 month for speed to 5 months for cardiorespiratory endurance. For powerLOW and static balance, the positive pandemic effects translate to developmental gains of 1 and 7 months, respectively. Pre-pandemic secular trends may account for some of the observed differences between pandemic and pre-pandemic cohorts, especially in powerLOW, powerUP and static balance. The pandemic further increased developmental delays of OTK children in cardiorespiratory endurance, powerUP and balance.ConclusionsThe Covid-19 pandemic was associated with declines in several physical fitness components in German third-graders. Pandemic effects are still visible in 2022. Health-related interventions should specifically target those physical fitness components that were negatively affected by the pandemic (cardiorespiratory endurance, coordination, speed).
KW - Sars-CoV-2
KW - Cohort study
KW - Cardiorespiratory endurance
KW - Muscle power
KW - Physical fitness
KW - Youth
KW - EMOTIKON
KW - Linear mixed models
Y1 - 2023
U6 - https://doi.org/10.1186/s40798-023-00624-1
SN - 2198-9761
VL - 9
IS - 1
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Jebabli, Nidhal
A1 - Zouhal, Hassane
A1 - Boullosa, Daniel
A1 - Govindasamy, Karuppasamy
A1 - Tourny, Claire
A1 - Hackney, Anthony C.
A1 - Granacher, Urs
A1 - Ben Abderrahman, Abderraouf
T1 - The effects of preferred music and its timing on performance, pacing, and psychophysiological responses during the 6-min test
JF - Journal of human kinetics
N2 - The aim of this study was to investigate the effects of listening to preferred music during a warm up or exercise, on performance during a 6-min all-out exercise test (6-MT) in young adult males. Twenty-five healthy males volunteered to participate in this study. Following a within subject design, participants performed three test conditions (MDT: music during the test; MDW: music during the warm-up; WM: without music) in random order. Outcomes included mean running speed over the 6-min test (MRS6), total distance covered (TDC), heart rate responses (HRpeak, HRmean), blood lactate (3-min after the test), and the rating of perceived exertion (RPE); additionally, feeling scale scores were recorded. Listening to preferred music during running resulted in significant TDC (Delta up arrow 10%, p=0.006, ES=0.80) and MRS6 (Delta up arrow 14%, p=0.012, ES=1.02) improvement during the 6-MT, improvement was also noted for the warm-up with music condition (TDC:Delta up arrow 8%, p=0.028, ES=0.63; MRS6:Delta up arrow 8%, p=0.032, ES=0.61). A similar reverse "J-shaped" pacing profile was detected during the three conditions. Blood lactate was lower in the MDT condition by 8% (p=0.01, ES=1.10), but not the MDW condition, compared to MW. In addition, no statistically significant differences were found between the test sessions for the HR, RPE, and feeling scale scores. In conclusion, listening to music during exercise testing would be more beneficial for optimal TDC and MRS6 performances compared to MDW and WM.
KW - rating of perceived exertion
KW - work-rate distribution
KW - blood lactate;
KW - aerobic exercise
Y1 - 2022
U6 - https://doi.org/10.2478/hukin-2022-0038
SN - 1640-5544
SN - 1899-7562
VL - 82
IS - 1
SP - 123
EP - 133
PB - Academy of Physical Education
CY - Katowice
ER -
TY - JOUR
A1 - Saidi, Karim
A1 - Zouhal, Hassane
A1 - Boullosa, Daniel
A1 - Dupont, Gregory
A1 - Hackney, Anthony C.
A1 - Bideau, Benoit
A1 - Granacher, Urs
A1 - Ben Abderrahman, Abderraouf
T1 - Biochemical markers and wellness status during a congested match play period in elite soccer players
JF - International journal of sports physiology and performance : IJSSP
N2 - Objectives:
To analyze biochemical markers, wellness status, and physical fitness in elite soccer players in relation to changes in training and match exposure during a congested period of match play.
Methods:
Fourteen elite soccer players were evaluated 3 times (T1, T2, and T3) over 12 weeks (T1-T2: 6-wk regular period of match play and T2-T3: 6-wk congested period of match play). Players performed vertical jump tests, repeated shuttle sprint ability test, and the Yo-Yo Intermittent Recovery Test at T1, T2, and T3. Plasma C-reactive protein, creatinine, and creatine kinase were analyzed at T1, T2, and T3. Wellness status was measured daily using the Hopper questionnaire (delayed onset of muscle soreness, stress, fatigue, and sleep quality). Training session rating of perceived exertion was also recorded on a daily basis.
Results:
A significant increase was found in stress, fatigue, delayed onset of muscle soreness scores, and Hopper index during the congested period (between T2 and T3) compared with the regular period (between T1 and T2) (.001 < P < .008, 0.8 < ES < 2.3). Between T2 and T3, significant relationships were found between the percentage variations (Delta%) of C-reactive protein, and Delta% of creatine kinase with the Hopper Index, and the Delta% of fatigue score. In addition, the Delta% of fatigue score and Delta% of delayed onset of muscle soreness score correlated with Delta% Yo-Yo Intermittent Recovery Test and Delta% best of repeated shuttle sprint ability test (.49 < r < P < .01).
Conclusions:
An intensive period of congested match play significantly compromised elite soccer players' physical fitness and wellness status. Elite soccer players' wellness status reflects declines in physical fitness during this period while biochemical changes do not.
KW - training
KW - congested calendar
KW - overtraining
KW - overreaching
KW - recovery
Y1 - 2022
U6 - https://doi.org/10.1123/ijspp.2020-0914
SN - 1555-0265
SN - 1555-0273
VL - 17
IS - 4
SP - 605
EP - 620
PB - Human Kinetics Publ.
CY - Champaign
ER -
TY - JOUR
A1 - Negra, Yassine
A1 - Sammoud, Senda
A1 - Uthoff, Aaron
A1 - Moran, Jason
A1 - Ramirez-Campillo, Rodrigo
A1 - Chaabene, Helmi
T1 - The effects of repeated backward running training on measures of physical fitness in youth male soccer players
JF - Journal of sports sciences
N2 - This study explored the effects of an 8-week repeated backward running training (RBRT) programme on measures of physical fitness in youth male soccer players. Youth male soccer players were randomly allocated into a RBRT group (n = 20; 13.95 +/- 0.22y) or a control group (CG; n = 16; 14.86 +/- 0.29y). The CG continued normal soccer training, while the RBRT group replaced some soccer drills with RBRT twice per week. Within-group analysis revealed that RBRT improved all performance variables ( increment -9.99% to 14.50%; effect size [ES] = -1.79 to 1.29; p <= 0.001). Meanwhile, trivial-to-moderate detrimental effects on sprinting and change of direction (CoD) speed ( increment 1.55% to 10.40%; p <= 0.05) were noted in the CG. The number of individuals improving performance above the smallest worthwhile change ranged from 65-100% across all performance variables in the RBRT group, whereas<50% in the CG reached that threshold. The between-group analysis indicated that the RBRT group improved performance on all performance tasks more than the CG (ES = -2.23 to 1.10; p <= 0.05). These findings demonstrate that substituting part of a standard soccer training regimen with RBRT can enhance youth soccer players' sprinting, CoD, jumping, and RSA performance.
KW - musculoskeletal and neural physiological phenomena
KW - human physical conditioning
KW - movement
KW - muscle strength
KW - youth team sports
Y1 - 2023
U6 - https://doi.org/10.1080/02640414.2023.2184770
SN - 0264-0414
SN - 1466-447X
VL - 40
IS - 24
SP - 2688
EP - 2696
PB - Routledge, Taylor & Francis Group
CY - London
ER -
TY - JOUR
A1 - Prieske, Olaf
A1 - Chaabene, Helmi
A1 - Puta, Christian
A1 - Behm, David George
A1 - Büsch, Dirk
A1 - Granacher, Urs
T1 - Effects of Drop Height on Jump Performance in Male and Female Elite Adolescent Handball Players
JF - International journal of sports physiology and performance
N2 - Purpose: To examine the effects of drop height on drop-jump (DJ) performance and on associations between DJ and horizontal-jump/sprint performances in adolescent athletes. Methods: Male (n = 119, 2.5 [0.6] y post-peak-height velocity) and female (n = 120, 2.5 [0.5] y post-peak-height velocity) adolescent handball players (national level) performed DJs in randomized order using 3 drop heights (20, 35, and 50 cm). DJ performance (jump height, reactive strength index [RSI]) was analyzed using the Optojump Next system. In addition, correlations were computed between DJ height and RSI with standing-long-jump and 20-m linear-sprint performances. Results: Statistical analyses revealed medium-size main effects of drop height for DJ height and RSI (P <.001, 0.63 <= d <= 0.71). Post hoc tests indicated larger DJ heights from 20 to 35 and 35 to 50 cm (P <=.031, 0.33 <= d <= 0.71) and better RSI from 20- to 35-cm drop height (P <.001, d = 0.77). No significant difference was found for RSI between 35- and 50-cm drop height. Irrespective of drop height, associations of DJ height and RSI were small with 5-m-split time (-.27 <= r <=.05), medium with 10-m-split time (-.44 <= r <=.14), and medium to large with 20-m sprint time and standing-long-jump distance (-.57 <= r <=.22). Conclusions: The present findings indicate that, irrespective of sex, 35-cm drop heights are best suited to induce rapid and powerful DJ performance (ie, RSI) during reactive strength training in elite adolescent handball players. Moreover, training-related gains in DJ performance may at least partly translate to gains in horizontal jump and longer sprint distances (ie, >= 20-m) and/or vice versa in male and female elite adolescent athletes, irrespective of drop height.
KW - stretch-shortening cycle
KW - plyometric training
KW - strength training
KW - tendon stiffness
KW - young athletes
Y1 - 2019
U6 - https://doi.org/10.1123/ijspp.2018-0482
SN - 1555-0265
SN - 1555-0273
VL - 14
IS - 5
SP - 674
EP - 680
PB - Human Kinetics Publ.
CY - Champaign
ER -
TY - JOUR
A1 - Brand, Johannes
A1 - Franke, Vanessa
T1 - Verantwortungseigentum und Profifußball
BT - eine Organisationsform für werteorientierte Fußballvereine?
JF - Zeitschrift für Sport und Recht
N2 - Verantwortungseigentum ist mittlerweile mehr als ein Nischenthema innerhalb der Rechtswissenschaft und unternehmerischen Praxis. Unternehmen werden in Verantwortungseigentum gegründet oder umgewandelt, also die persönlichen Gewinne der Gesellschafter perpetuiert und die Nachfolge reguliert. Auch der Profifußball stellt sich immer wieder die Frage nach der richtigen Balance zwischen Gewinnstreben und Gemeinwohl. Das wirft Fragen nach alternativen Gestaltungsmöglichkeiten auf, für die das Verantwortungseigentum eine Lösung bieten könnte.
Y1 - 2023
UR - https://beck-online.beck.de/Bcid/Y-300-Z-SPURT-B-2023-S-196-N-1
SN - 0945-3873
VL - 30
IS - 3
SP - 196
EP - 201
PB - Beck
CY - München
ER -
TY - JOUR
A1 - Lehmann, Nico
A1 - Kuhn, Yves-Alain
A1 - Keller, Martin
A1 - Aye, Norman
A1 - Herold, Fabian
A1 - Draganski, Bogdan
A1 - Taube, Wolfgang
A1 - Taubert, Marco
T1 - Brain activation during active balancing and its behavioral relevance in younger and older adults
BT - a functional near-infrared spectroscopy (fNIRS) study
JF - Frontiers in Aging Neuroscience
N2 - Age-related deterioration of balance control is widely regarded as an important phenomenon influencing quality of life and longevity, such that a more comprehensive understanding of the neural mechanisms underlying this process is warranted.
Specifically, previous studies have reported that older adults typically show higher neural activity during balancing as compared to younger counterparts, but the implications of this finding on balance performance remain largely unclear.
Using functional near-infrared spectroscopy (fNIRS), differences in the cortical control of balance between healthy younger (n = 27) and older (n = 35) adults were explored.
More specifically, the association between cortical functional activity and balance performance across and within age groups was investigated. To this end, we measured hemodynamic responses (i.e., changes in oxygenated and deoxygenated hemoglobin) while participants balanced on an unstable device.
As criterion variables for brain-behavior-correlations, we also assessed postural sway while standing on a free-swinging platform and while balancing on wobble boards with different levels of difficulty.
We found that older compared to younger participants had higher activity in prefrontal and lower activity in postcentral regions.
Subsequent robust regression analyses revealed that lower prefrontal brain activity was related to improved balance performance across age groups, indicating that higher activity of the prefrontal cortex during balancing reflects neural inefficiency.
We also present evidence supporting that age serves as a moderator in the relationship between brain activity and balance, i.e., cortical hemodynamics generally appears to be a more important predictor of balance performance in the older than in the younger. Strikingly, we found that age differences in balance performance are mediated by balancing-induced activation of the superior frontal gyrus, thus suggesting that differential activation of this region reflects a mechanism involved in the aging process of the neural control of balance.
Our study suggests that differences in functional brain activity between age groups are not a mere by-product of aging, but instead of direct behavioral relevance for balance performance.
Potential implications of these findings in terms of early detection of fall-prone individuals and intervention strategies targeting balance and healthy aging are discussed.
KW - aging
KW - neuroimaging
KW - functional near-infrared spectroscopy (fNIRS)
KW - balance
KW - postural control
KW - prefrontal cortex
KW - neural inefficiency
Y1 - 2022
U6 - https://doi.org/10.3389/fnagi.2022.828474
SN - 1663-4365
VL - 14
PB - Frontiers Media
CY - Lausanne
ER -
TY - JOUR
A1 - Keller, Sebastian
A1 - Notbohm, Hannah Lisa
A1 - Bloch, Wilhelm
A1 - Schumann, Moritz
T1 - Reduced serum concentrations of reactive oxygen and nitrogen species following strenuous exercise in the heat are not associated with an upregulation in serum antioxidative capacity
JF - Baltic Journal of Health and Physical Activity
N2 - Introduction:
Reactive oxygen and nitrogen species (RONS) are produced as a response to exercise and play a part in guiding the adaptive response to physical training.
Exercise in the heat has been shown to further increase accumulation of RONS in systemic circulation; however, a high antioxidative response or heat acclimatization mechanisms could attenuate this response.
In a previous study, we found reduced RONS concentrations in trained athletes following strenuous cycling in the heat. Therefore, this secondary analysis assessed whether these reduced RONS serum concentrations are induced by an increased serum antioxidant capacity.
Methods:
Twelve male cyclists (V?O2peak: 60 +/- 4 ml center dot kg-1 center dot min-1) completed a 60-minute constant workload trial (55% peak power output, ambient temperature 30.4 +/- 0.6 degrees C) with and without ice vest in a randomized order.
The core body temperature (Tcore) was measured by an ingestible capsule. Blood samples were collected before and after each trial to determine superoxide dismutase (SOD) and catalase (CAT) activity, total antioxidant capacity (TAC) and RONS.
Due to the absence of between-group differences, data of both conditions were pooled. Results: Tcore statistically increased (p < 0.001) over the experimental trials (+6.0 +/- 1.6%, effect size (ES) = 5.6). Concentrations of RONS (-17.2 +/- 15.5%, p < 0.001, ES = 1.0) and TAC (-8.9 +/- 22.9%, p = 0.04, ES = 0.7) statistically decreased, while the activity of CAT (+15.5 +/- 84.0%, p = 0.90, ES = 0.04) and SOD (+9.2 +/- 58.7%, p = 0.98, ES = 0.01) remained unchanged.
Conclusions:
Reduced serum RONS concentrations after strenuous cycling in the heat were not associated with upregulation of serum antioxidant capacity in trained athletes.
The prooxidant-antioxidant balance may rather be regulated at a myocellular level and should be further assessed in future studies.
KW - total antioxidant
KW - capacity
KW - antioxidants
KW - catalase
KW - reactive oxygen
KW - species
KW - superoxide dismutase
KW - sports medicine
Y1 - 2022
U6 - https://doi.org/10.29359/BJHPA.14.4.03
SN - 2080-9999
VL - 14
IS - 4
PB - Gda`nsk Academy; Versita, Warsaw
CY - Gdansk
ER -