Exercise physiology in geriatric practice.

Between now and the end of the century, we can expect a 45% increase in the proportion of the population aged 85 and over. The age-related loss of muscle mass and diminishing exercise tolerance mean that a large and increasing number of elderly people will be living at or near 'thresholds' of physical ability, needing only a minor intercurrent illness to render them dependent. Although much of the decline is obligatory, the effects of physical training are much the same, proportionally, in old age as in youth. Not only can exercise reverse the effects of immobilization, it can readily produce a further 10 to 20% improvement in strength and aerobic power, effectively postponing functionally important thresholds for some 10 to 20 years. There is an urgent need for close collaboration between exercise physiologists and geriatric clinicians. The relationship between disability in activities of daily living and age-related impairment of physical performance is especially ripe for study.