Postural sway during standing and unexpected disturbance of balance in random samples of men of different ages.

Postural sway behavior while standing and during and after an unexpected disturbance of balance was examined in men aged 31 to 35, 51 to 55, and 71 to 75 years. The groups studied were random samples of men living in the town of Jyväskylä in 1981. Postural sway while standing was more pronounced in the older age groups, whereas after a disturbance of balance postural sway was nearly the same in all age groups. The functioning of the postural control system was correlated with the vibratory threshold on the ankles, grip strength, as well as with aerobic and anaerobic capacity within the age groups. Further, in the youngest age group the functioning of the postural control system was poorer among those who had been subject to noise at their work. The correlation between health status and postural sway was negligible. The results may indicate the partly parallel and similar effects of aging, poor physical fitness, and harmful environmental factors on the functioning of the postural control system.