Past, present and future of the critical power concept

Current knowledge. - The critical power concept was proposed in the studies carried Out by Scherrer from 1954 to 1960. These studies found a linear relationship between the time to exhaustion and the total work performed during a local exercise. The slope of this relationship has the meaning of a critical power, i.e. a power output sustainable during a long time. Y intercept of this relationship has the dimension of an energy store. In 1958, Scherrer proposed the application of the critical power concept to athlete testing in running and swimming. In fact, the time limit-work limit is not perfectly linear as noted by Scherrer. The main consequence of this linear approximation is an overestimation of the true critical power and of the prediction of exhaustion times around critical power. The results of studies rediscovering the application of critical power to general exercises are presented, especially those carried out in Monod's Laboratory showing that critical power is close to a steady state of several physiological parameters, provided that this power if computed with exhaustion times ranging from 4 up to 30 min. The corollary of the unaccuracy of the prediction of exhaustion times is that the computation of critical power is insensitive to large differences in exhaustion times. Prospects. - Critical power will stay an interesting index of the aptitude to long lasting exercises, especially local exercises. On the other hand, it is unlikely that Y intercept will be used as an index of anaerobic capacity. (C) 2008 Elsevier Masson SAS. Tous droits reserves.