The effect of movement velocity and eccentric contractions on the bilateral deficit
Abstract
This study was performed to examine the effects of movement velocity and eccentric contractions on the bilateral deficit. To accomplish this, 18 participants performed bilateral and unilateral contractions eccentrically and concentrically across 6 movement velocities (30, 60, 90, 120, 150, and 180{dollar}\sp\circ{dollar}/s). Repeated measures ANOVA's revealed that for both eccentric and concentric contractions, significant differences existed between bilateral and summed unilateral contractions; and at each of the six tested velocities. Further analyses revealed that the degree of the bilateral deficit increased as movement velocity increased. It is believed that the decreased tension developed during bilateral eccentric and concentric contractions, is attributed to incomplete activation of fast twitch muscle fibers recruited during unilateral contractions.