A descriptive epidemiology of physical activity from a Northern Ireland perspective.

The benefits of physical activity are well documented and exercise is included in most health promotion recommendations but, before adopting a population strategy, it is important to establish baseline patterns of physical activity so as to make regional and international comparisons and measure behaviour change. This review examines adult physical activity participation in a national and international context and highlights how difficult it is to draw meaningful conclusions and detect trends from studies that measure physical activity using different measuring instruments. Overall, about 4 in 5 people are active at least occasionally but the more rigorous the definition of habitual physical activity the lower the participation rates so that less than 1 in 5 people perform regular vigorous physical activity. Males are more active than females with a decrease in physical activity with increasing age. There is a social class gradient with those in social classes 1 and 2 being more active.