Most of wheelchair athletes must have an excellent capacity for both aerobic and anaerobic work. The rate of doing work is defined as aerobic power and anaerobic power. Usually, the maximal aerobic power is indicated by the maximal oxygen consumption to perform the work; because of the difficulty in evaluating the amount of energy delivered anaerobically, the maximal anaerobic power is evaluated by determining the maximal mechanical power output of the subject. Whereas the methods for evaluating the maximal aerobic power of athletes are rather well documented (Coutts 1984; Glaser et al. 1980; Wicks et al. 1983), the methods for evaluating the maximal mechanical power output are less so; moreover, they include two major limitations: (a) the test is done on a wheelchair ergometer, and, therefore, there is no air resistance and (b) the duration of the test is too long, i.e., 30 s.