Efficiency of pedal forces during ergometer cycling.

The aim of this study was to record the forces applied to the pedal during ergometer cycling and to calculate the effectiveness of these force vectors. Six healthy subjects rode a weight-braked bicycle ergometer at different work loads, pedaling rates, saddle heights, and pedal foot positions. The left lower limb and crank motions were recorded by a cinefilm camera and pedal reaction forces by a Kistler force measuring transducer mounted on the left pedal. The force effectiveness was computed as a ratio between the force tangential to instantaneous direction of pedal movement and the resultant force. The mean force efficiency ratio significantly increased by an increase of the ergometer work load or use of the anterior foot position instead of the posterior. It was not significantly changed due to alterations of the pedaling rate or saddle height.