Effect of light and vigorous physical activity on balance and gait of older adults.

This study aims to quantitatively assess the effects of vigorous and light physical activity (VPA, LPA) on static balance, gait and sit-to-stand (STS) tasks in a cohort of healthy older adults. To this end, 34 individuals of age >65 years were divided into two groups (n=17 each) who underwent 36 sessions (3×12 weeks) of PA characterized by different levels of intensity, assessed through continuous heart rate monitoring during the training session. Their balance and mobility were objectively evaluated on the basis of postural sway and time of STS measurements performed using a force platform. The main spatiotemporal parameters of gait (i.e. speed, stride and gait cycle duration, stance, swing and double support phase duration) were also acquired using a wearable inertial measurement unit. The results show that most gait parameters and STS time significantly improve in the VPA group but not in the LPA one. For the latter group a reduction only of swing phase duration was detected. PA also induced a generalized reduction of postural sway in both groups in the case of absence of visual input. These findings suggest that PA programs characterized by superior levels of intensity might be more suitable in generally improving static and dynamic daily motor tasks, while in terms of static balance acceptable results can be achieved even when only light activity is performed.