Critical power of knee extension exercises does not depend upon maximal strength

Abstract : A possible dependence of critical power (CP) and the Y-intercept of the work/exhaustion time relationship (Yintcrccpt) on maximal muscular strength of the same muscle group has been studied in nine endurance-trained subjects. seven gymnasts. and seven weight-lift-ers. CP was calculated as being equal to the slope of the linear rel a tionship between exhaustion ti me and the work performed at exhaustion on a knee extension er-gometer. Yinterccpt was equal to the intercept between this relationship and the work axis. The muscular strength of the knee was evaluated by measuring the torques exerted on a Biodex knee isokinetic dynamometer at four angular velocities: 0° · s-1 (T 0). 90° · Ç 1 (T 90). usoo · s-1 (T1xol and 240° · s-1 (T 240). The results of the present study do not support the hypothesis that CP depends upon maximal strength. Indeed. CP was not correlated with To. T 90· T 1 xo or T 240 (r < 0.01). Yintcrccpt was significantly and positively correlated only with T 90 .