Effects of age and physical activity on response speed in knee flexor and extensor muscles

Abstract

Abstract This study aims to determine the normalized response speed ( V rn ) in vastus lateralis (VL) and biceps femoris (BF) muscles in different age groups using tensiomyography. Eighty-four male subjects were divided into four age groups: teenage subjects (T); undergraduate students (U), adult subjects (A), and the elderly group (E). Differences in V rn were observed between E and T ( p = 0.000), E and U ( p = 0.000), and E and A ( p = 0.018) for right VL and between E and T ( p < 0.000) and U ( p = 0.003) for left VL; between T and U ( p = 0.010) and A ( p = 0.000) for right VL, and A ( p = 0.004) for left VL. V rn in the BF displayed different behavior from that of the VL, increasing moderately or stabilizing and declining slightly in E, in right leg ( p = 0.020). The data obtained highlighted a decline in V rn for the VL in both legs with increasing age and, declines in BF response speed were observed only in E.