Relaxation rate and contraction remainder of human forearm flexors following fatiguing repetitive handgrip / 体力科学

ABSTRACT

Relaxation rate and contraction remainder of human forearm flexors following fatiguing repetitive handgrips were studied. These parameters were measured from the forearm girth and recorded by the use of a mercury-in-rubber gauge.<BR>Subjects performed handgrips: Subjects lifted and lowered the load of 30% of the maximum grip strength at a distance of 2 cm with rhythm of 1 Hz.<BR>1) During the muscle relaxations, the decrease rate of forearm girth in the falling period and/or the lowering stage of the load increased with repetition of handgrips.<BR>2) The forearm girth at the onset of handgrip progressively increased.<BR>3) Even after the handgrips, the resting forearm girth continued to increase for a few minutes, and then progressively decreased. But it did not completely recover its resting level even after 1 hr.<BR>From these results, it is suggested that human muscles fatigued with repetitive contractions cause 'contraction remainder' in addition to the delay of muscle relaxation.