MEASUREMENT OF THE POWER OUTPUT DURING THE ACCELERATION PHASE OF ALL-OUT ARM CRANKING EXERCISE

The purpose of this study was to develop an original friction loaded e rgometer allowing measurement of the resisting torque (M-b) and the an gular velocity (omega) by means of a force transducer and an optical p ick-up during all-out arm cranking exercises. Taking into account the kinetic energy variations of the flywheel, the peak power developed at the cranke (P-peak(c)) and the peak angular velocity (omega(peak)) we re determined in 6 male and 6 female able-bodied subjects during 6-8 b outs of 3 s duration, performed at maximal velocity, with Mh varying f rom 0.07 to 0.87 Nm . kg(-1), In each subject, the M-b increase was re lated to a decrease of omega(peak). This relationship was expressed th rough a negative linear regression (0.92<R-2<0.99) for omega(peak) bet ween 13 and 28 rad . s(-1) for the males and 10 and 24 rad . s(-1) for the females. The relationship between P-peak(c) and M-b did not fit w ell for all subjects (0.01<R-2<0.93) with a parabolic equation, indica ting that for upper limb testing, the maximal power should be defined as the highest power measured during several bouts performed with appr opriate resisting torque. The present study also demonstrated the impo rtance of talking into account the inertia of the moving flywheel duri ng the acceleration phase of an all-out arm crank exercise, when deter mining the peak power output.