ESTIMATION OF POWER OUTPUT FROM LEG EXTENSOR MUSCLES IN THE ACCELERATION PHASE OF THE SPRINT

The purpose of this study was to estimate the transfer of mechanical power from hip to knee, and from knee to ankle, performed by the RF and GAS muscles during the acceleration phase of sprinting. The energy transfer was estimated using a muscular skeletal model. The energy transferred by RF from hip to knee during the push off phase was 72.6±14.5 J (34.4±5.5 % of net knee joint work) and the transfer of energy by GAS from knee to ankle was 23.3±3.6 J (24.9±7.3 % of net ankle joint work). This energy transfer allows high power output on the more distal joint, and could provide a partial explanation of why the moments of force on actual explosive sport movements exceed the values obtained in an isometric test.