Differences in Kinematic and Electromyographic Characteristics Between Young and Older Adults During Circular Turning

Abstract

Direction change while walking is a complex task of locomotor activity and is necessary during daily activities, but little is known about whether aging alters turn-related characteristics compared with straight walking. The objective of this study was to investigate the effects of aging on the biomechanical characteristics and walking velocity during circular turning. The participants included 17 healthy older adults (65–80 years old) and 16 young adults. Walking velocity, the first and second peak knee flexion, ankle plantarflexion, ankle dorsiflexion, and electromyographic amplitudes of the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medialis were measured during walking along a 5 m straight path and a 5 m circumference curved path with a radius of 0.8 m. The two groups made comparable decreases in turning velocity as compared with straight walking, but older adults decreased the second peak knee flexion instead of the second peak ankle plantarflexion, and the knee remained flexed during the loading response. Older people also needed higher amplitudes of the tibialis anterior in the outer leg, and biceps femoris in the inner leg, to facilitate turning, which were not seen in young adults. Moreover, older adults did not decrease amplitudes of the rectus femoris and biceps femoris in the outer leg, and tibialis anterior in the inner leg, as noted in young adults. Aging does not exert further effects on turning velocity, but older adults use different biomechanical strategies to turn.