Effect of pedaling technique on muscle activity and cycling efficiency

The purpose of this study was to examine the acute effect of talocrural joint position on muscle activity and gross mechanical efficiency (GE). Eleven trained cyclists participated in three randomized 6-min cycling bouts at approximately 80% of maximal aerobic capacity on an electromagnetically braked cycle ergometer while oxygen consumption and muscle activity (EMG) were monitored during the subject's self-selected pedaling technique (control) and while using a dorsi- and plantarflexed pedaling technique. The mean differences in range of motion of the dorsi- and plantarflexed technique from the control position were 7.1 +/- 4.4 and 6.9 +/- 5.4 degrees , respectively. Gastrocnemius EMG activity was higher with the dorsiflexion technique than when using the self-selected control position (33.2 +/- 13.0 and 24.2 +/- 8.4 microV s, respectively; P < 0.05). Moreover, GE was 2.6% lower while riding with the dorsiflexion technique than the control position (19.0 +/- 1.2 and 19.5 +/- 1.3%, respectively; P < 0.05). The data suggested that introducing more dorsiflexion into the pedal stroke of a trained cyclist increases muscle activity of the gastrocnemius lateralis and decreased GE when compared to the self-selected pedal stroke.