ACUTE EFFECTS OF SMALL CHANGES IN CRANK LENGTH ON TORQUE WAVEFORM DURING SUBMAXIMAL PEDALLING

The purpose of the present study was to evaluate the acute effects of small changes in crank-arm length and pedalling power on crank torque-angle profile during seated cycling. Twelve amateur cyclists participated and performed 12 sets of 5-min submaximal pedalling on a special cycle ergometer (4 intensities x 3 crank lengths). Principal Component Analysis technique was used to analyse ten crank torque-angle curves of the right leg. A longer crank increased the crank torque of the front leg (30-125º) in order to lift the rear leg (200-320º), contrary to the effect of increasing pedalling power. Furthermore, pedalling with the longest crank required higher torque values after reaching peak torque (110-170º) compared to the shortest ones. In conclusion, contrary to the lore, a longer crank requires a higher mechanical effort compared to a shorter crank for pedalling at the same intensity