Efficiency and proficiency of bimanual cranking: differences between two cranking patterns.

The efficiency and motor proficiency of an arm ergometer exercise were evaluated for two different cranking methods, cranking in the forward and reverse directions. 8 young men participated. Their heart rates were measured as an index of energy consumption. The proficiency of elbow-joint motion was assessed in terms of its consistency (intrasubject variability in cycle period, peak velocity, and peak acceleration) and smoothness (jerk cost). Heart rates and jerk costs were lower during exercise in the forward direction than in the reverse direction. These results suggest that improved efficiency accompanied improved motor proficiency in terms of smoothness of movement for arm ergometer exercises under different cranking conditions.