Grant: Travel Awards - Institute Community Support

Physical activity is believed to play an important role in extending life and improving health. Although it is known that physical activity increases lifespan, the exact benefits are unknown, as all previous studies examining this relationship have used physical activity measures susceptible to human error (i.e., questionnaires). This has likely led to a perceived weakened relationship between levels of physical activity and risk of mortality. This study aimed to determine the true relationship between physical activity and mortality risk, through the use of objective measures of activity. To do this, we used an American health behaviour survey that required participants to wear accelerometers - a small and portable device that measures intensity of activity - to measure activity for one week. We found that adults who were the least active were at a 70% higher risk of mortality compared to those who reached the Canadian physical activity target of 150 mins/week of activity. This risk was found to decrease considerably as levels of activity increased, regardless of BMI. These findings are troubling considering less than 5% of Canadian adults are currently meeting physical activity targets. The strength of the relationship observed in this study is considerably stronger than those cited in the past, emphasizing the importance of public health interventions to get people active.