Evaluation of an innovative critical power model in intermittent vertical jump

The aim of this study was to test if the critical power model can be used to determine the critical rest interval (CRI) between vertical jumps. Ten males performed intermittent countermovement jumps on a force platform with different resting periods (4.1+/-0.3 s, 5.0+/-0.4 s, 5.9+/-0.6 s). Jump trials were interrupted when participants could no longer maintain 95% of their maximal jump height. After interruption, number of jumps, total exercise duration and total external work were computed. Time to exhaustion (s) and total external work (J) were used to solve the equation Work=a+b x time. The CRI (corresponding to the shortest resting interval that allowed jump height to be maintained for a long time without fatigue) was determined dividing the average external work needed to jump at a fixed height (J) by b parameter (J/s). In the final session, participants jumped at their calculated CRI. A high coefficient of determination (0.995+/-0.007) and the CRI (7.5+/-1.6 s) were obtained. In addition, the longer the resting period, the greater the number of jumps (44+/-13, 71+/-28, 105+/-30, 169+/-53 jumps; p<0.0001), time to exhaustion (179+/-50, 351+/-120, 610+/-141, 1,282+/-417s; p<0.0001) and total external work (28.0+/-8.3, 45.0+/-16.6, 67.6+/-17.8, 111.9+/-34.6kJ; p<0.0001). Therefore, the critical power model may be an alternative approach to determine the CRI during intermittent vertical jumps.