Bicycle pedalling forces as a function of pedalling rate and power output

Eleven men with recreational bicycling experience rode a bicycle ergometer with instrumented force pedals to determine the effects of pedalling rate and power output on the total resultant pedal force, Fr, and the component of the force perpendicular to the crank arm. The force patterns were obtained at power outputs of 100 W and 200 W for pedalling rates of 40-120 rpm in intervals of 10 rpm. Data were not obtained at 40 rpm at the 200 W power output. The Fr averaged over a crank cycle (Far) was lowest at 90 rpm and 100 W, a value statically different (P less than 0.05) from those at 40, 50, and 120 rpm. At 200 W, the Fr was lowest at 100 rpm, a value statistically different (P less than 0.05) from those at 50, 60, and 70 rpm. The Far varied widely (range of 30% of mean for all subjects) for individuals at a given power output. The results suggest that pedalling at 90-100 rpm may minimize peripheral forces and therefore peripheral muscle fatigue even though this rate may result in higher oxygen uptake.