TY  - JOUR
PY  - 2013//
TI  - Child-adult differences in the kinetics of torque development
JO  - Journal of sports sciences
A1  - Dotan, Raffy
A1  - Mitchell, Cameron
A1  - Cohen, Rotem
A1  - Gabriel, David
A1  - Klentrou, Panagiota
A1  - Falk, Bareket
SP  - 945
EP  - 953
VL  - 31
IS  - 9
N2  - Abstract Children have lower size-normalised maximal voluntary force, speed, and power than adults. It has been hypothesised that these and other age-related performance differences are due to lesser type-II motor-unit utilisation in children. This should be manifested as slower force kinetics in explosive muscle contractions. The purpose of this study was to investigate the nature of child-adult force-kinetics differences and whether the latter could support that hypothesis. Untrained boys (n = 20) and men (n = 20) (10.1 ± 1.3 and 22.9 ± 4.4 years, respectively), performed maximal, explosive, isometric elbow flexions and knee extensions on a Biodex dynamometer. Peak torque (MVC), times to 10-100% MVC, and other kinetics parameters were determined. The boys' body-mass-normalised knee extension MVC, peak rate of torque development, and %MVC at 100 ms were 26, 17 and 23% lower compared with the men and their times to 30% and 80% MVC were 24 and 48% longer, respectively. Elbow flexion kinetics showed similar or greater differences. The findings illuminate boys' inherent disadvantage in tasks requiring speed or explosive force. It is demonstrated that the extent of the boys-men kinetics disparity cannot be explained by muscle-composition and/or musculo-tendinous-stiffness differences. We suggest therefore that the findings indirectly support children's lower utilisation of type-II motor units.<p />  <p>Language: en</p>
LA  - en
SN  - 0264-0414
UR  - http://dx.doi.org/10.1080/02640414.2012.757343
ID  - ref1
ER  -