ABSTRACT
T hroughout the lifespan of humans, physical performance and physiologicalfunctioning improve rapidly from early childhood to a maximum somewhere between the late teens and about 30 years of age. Then, in most cases, a slow decline occurs during adulthood that becomes more rapid with increasing age. These declines in functioning are associated with age-related decreases in physical activity as well as the inevitable effects of aging. In general, however, the rates of decline in physical performance are more highly related to the decreased habitual activity than to age itself. Thus, regular physical activity throughout life can decrease the rate of decline in physiological functioning and physical performance.
