Figure 3. Influence of movement velocity on acceleration and EMG during shortening and lengthening contractions.

Index finger acceleration and the average rectified EMG for first dorsal interosseus during lengthening and shortening contractions. Values are means ±s.e.m. of the standard deviation (s.d.) for six targeted velocities. The s.d. of acceleration during the three fastest lengthening contractions was significantly greater (*) than that during the three fastest shortening contractions. EMG amplitude during the shortening contractions was greater than that during the lengthening contractions. Reproduced from Christou et al. (2003) with permission.