Force and EMG power spectrum during eccentric and concentric actions

Abstract

These results suggest that it is difficult to maintain the maximal eccentric force throughout the whole range of motion. Maximal EMG activity and frequencies of the EMG power spectrum can be at the same level or lower in eccentric actions as compared with concentric actions, depending on the joint angle and preactivation mode. The results of the EMG power spectrum do not support the concept that in maximal eccentric actions fast units are selectively activated.