Maximal mechanical power output and capacity of cyclists and young adults.

The maximal average power output (Wmax) has been examined in 10 male students, 22 pursuit and 12 sprint cyclists. In 24 of these subjects (8 students, 10 pursuit and 6 sprint cyclists), estimates of the maximal capacity (Wcap) of the short-term anaerobic energy yielding processes were made. The results show that the sprinters had a higher absolute Wmax (1241 +/- 266 W) and Wcap (16.7 +/- 4.9 kJ) than either the students (1019 +/- 183 W, 14.7 +/- 2.8 kJ) or the pursuit cyclists (962 +/- 206 W, 14.0 +/- 2.9 kJ). However, the differences were removed when the values were standardised for muscle size. In the sprinters the Wmax was attained at an optimal pedal frequency Vopt of 132 +/- 3 min-1 and the estimated maximal velocity of pedalling (V0) was 262 +/- 8 min-1. The comparable figures in the students and pursuit cyclists were 118 +/- 8 min-1, 235 +/- 17 min-1 and 122 +/- 6 min-1, 242 +/- 12 min-1 respectively. The coefficient of variation of duplicate measurements of Wcap was found to be +/- 9%. Using data of Wilkie (1968) for muscle phosphagen and glycolytic stores (27 mmol.kg-1), it was estimated that the probable efficiency of the anaerobic processes during maximal cycling was 0.22. It was concluded that Wmax and Wcap are largely determined by body size and muscularity. The efficiency of anaerobiosis appears to be of the same order of magnitude as found for oxidative work.