5 th Asia-Pacific Congress on Sports Technology (APCST)

To optimize training relating to the coordinative skills of athletes, a special cycle ergometer ARES with decoupled cranks was developed. The system is equipped with a measurement system to measure radial and tangential forces on the pedals, additionally to the acquisition of angle velocities of the two crank wheels. Due to the decoupled cranks, every leg performs its own revolution, and has to be active even at the pulling phase, without direct support of the opposite legs downstroke. To explore the unique possibilities of ARES, 4 subjects were tested on the ergometer in a first trial. After a short acclimatization phase to get familiar with the characteristics of the bike, the following tests were performed: (1) normal biking at different numbers of revolution with the challenge to keep a 180° phase angle, and (2) special coordination tasks: a) biking with 0° phase angle, b) Stop-and-go procedures with re-synchronization of the movement, c) counter-movement with both legs moving into opposite direction, and d) a lower half circle swing. During the exercises, forces on the pedals, the crank positions and current cadence were acquired. Out of this data, torque, power, angle velocities and an efficiency parameter were determined for the left and right leg. Variations in cadence, forces and torque as a function of pedal angle are clearly visible. A dependency on number of revolutions seems to be evident, caused by the higher coordinative challenge at high velocities. © 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of RMIT University