Role of Physical Activity in the Prevention and Treatment of Type 2 Diabetes

The prevalence of diabetes in Canada is already high and increasing. It is now estimated that 1.5 million or 5 % of the Canadian population has diagnosed diabetes, a number which is expected to rise to 3 million by the year 2010 (1). This rapid rise in the prevalence of a disease known to have serious health consequences underscores the need to develop effective intervention strategies. This brief review will summarize current knowledge with respect to the utility of physical activity (exercise) as a strategy for the prevention and treatment of type 2 diabetes. Role of physical activity in the prevention of type 2 diabetes. Epidemiological studies using cross-sectional data consistently report that physically active individuals are less likely to develop type 2 diabetes by comparison to sedentary individuals. For example, Mayer-Davis and colleagues reported that participation in both non-vigorous (moderate) and vigorous activity was associated with significantly higher values of insulin action in a cohort of 1467 men and women of African American, Hispanic and White ethnicity that included individuals with type 2 diabetes. Although attenuated, the association between physical activity and insulin action remained significant after controlling for body mass index and waist-hip ratio (2). These findings based on cross-sectional data are strengthened by evidence from prospective cohort studies