Physiological efficiency of constant power output at varying pedal rates

Abstract The study investigated the absolute and relative (% maximal) physiological demands of constant power output at three pedal rates chosen to incorporate the range used by racing cyclists. Following the assessment of maximal exercise capabilities utilizing a recently developed racing cycle ergometry system, ten highly trained racing cyclists undertook a randomized sequence of work bouts at low (70.0 ± 1.1), medium (94.8 ± 0.8) and high (126.5 ± 1.1) pedal rates per minute at constant power output under an unloaded (free wheel) condition and under a loaded (196.2 ± 8.0 W) condition which demanded approximately 75% VO2 max. In both the unloaded and loaded conditions absolute cardiorespiratory demands of work at the highest pedal rate were significantly higher than those at the low and medium pedal rates (P<0.05). Similarly, the relative (% max) cardiorespiratory demands of unloaded work at the highest pedalling rate were significantly greater that at low and medium pedal rates (P < 0.05). There were c...

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