Skeletal muscle function in man: force, relaxation rate, endurance and contraction time-dependence on sex and age

Two different methods for estimating muscle function were compared; hand grip strength (HGS) and adductor pollicis muscle function after electrical stimulation of the ulnar nerve. Fifty-two 'normal' subjects, who were divided into four groups, according to sex and age, were investigated. Technical modifications of the latter method are presented for the measurement of human skeletal muscle function, independent of the motivation of the subject. Maximal voluntary force, as measured with a hand dynamometer, was higher in males than in females. Young males were stronger than males over 50 years old, and young females were stronger than old women. The statistical analysis of the muscle function variables after electrical stimulation showed that young females developed relatively more force at low stimulating frequencies than females over 50 years old. Females had a significantly longer contraction time to tetany compared to males. The relaxation rate after tetanic stimulation was independent of sex and age. Endurance was reduced in old males compared to females in the same age-group and to young males.