For understanding hamstrings injury, activation properties and/or functional roles of hamstrings muscle group have been investigated during sports activities. In the present study, possible regional neuromuscular activation pattern within a hamstrings muscle were tested during isometric contractions and sprint running. Surface electromyography (SEMG) was detected along the longitudinal line of the biceps femoris muscle with 20 electrodes. Ten and eight male subjects performed two different joint torques, that the biceps femoris muscle contributes, of maximal voluntary isometric contraction and sprint running, respectively. Ratio of SEMG amplitude between two joint torques were uniform among the regions. SEMG pattern during sprint running were homogeneous within the biceps femoris muscle. These results suggest that the all regions of the biceps femoris muscle uniformly contribute to joint moments and are homogeneously regulated during sprint running.

DESCENTE SPORTS SCIENCE Vol.36/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE