Physical activity and health: Metabolic and cardiovascular issues

Currently, chronic non-communicable diseases, notably metabolic and cardiovascular diseases, are a major health-related burden of the populations of the industrialized and increasingly so also of the non-industrialized countries. Physical inactivity is one of the living habits that have been shown to be causally related to the most common metabolic and cardiovascular conditions, namely obesity, type 2 diabetes, metabolic syndrome, hypertension, coronary heart disease, stroke and peripheral arterial disease. The World Health Report 2002 estimates that globally the prevalence of physical inactivity among adults is at least 17%, and that of insufficient activity 41%, and that physical inactivity causes 1.9 million deaths and loss of 19 million disability-adjusted life-years (DALYs) annually, related to the health losses caused by coronary heart disease, stroke, breast cancer, colon cancer and type 2 diabetes. In Australia, DALY losses due to physical inactivity rank second (tobacco being first) among males and first among females. In Canada, physical inactivity is estimated to be attributable to 35.8% of coronary heart disease, 19.9% of stroke, 19.9% of hypertension, 19.9% of colon cancer, 11.0% of breast cancer and 19.9% of type 2 diabetes. The direct and indirect economic costs of physical inactivity in Canada are estimated to be 2.6% and those of obesity 2.2% of the total healthcare costs. These figures suggest that reaching sufficient levels of physical activity would decrease substantially the disease burden caused by metabolic and cardiovascular diseases. Evidence from a large number of observational studies and also from controlled trials indicates that the amount, strenuousness and type of physical activity needed to gain a substantial part of the potential health benefits is in principle feasible and safe for the majority of the people in industrial societies. However, changing physical activity habits at individual and especially at the population level have proved to be difficult. Therefore, effective measures are needed to increase people's opportunities and motivation to incorporate more physical activity into their daily lives. Healthcare personnel, particularly physiotherapists, have good opportunities to contribute to this important work.