Using Accelerometer Data to Estimate Reduced Mortality via Increased Exercise
We live in an age of comfort and engines of transport. As a result, few people exercise as much as they should in order to maintain optimal health. A sizable fraction of lost capacity with aging is due to sedentary behavior, as exhibited by studies showing that structured exercise programs can reduce mortality to a similar degree to widely used preventative medicine such as statins and antihypertensive drugs. The study noted here is another way of framing the well-known relationship between exercise and mortality in later life in our species: how many deaths would be avoided were people to exercise just a little more than is presently the case?
Previous studies suggest that a substantial number of deaths could be prevented annually by increasing population levels of physical activity. However, previous estimates have relied on convenience samples, used self-reported physical activity data, and assumed relatively large increases in activity levels (e.g., more than 30 minutes per day). The potential public health benefit of changing daily physical activity by a manageable amount is not yet known. In this study, we used accelerometer measurements (1) to examine the association of physical activity and mortality in a population-based sample of US adults and (2) to estimate the number of deaths prevented annually with modest increases in moderate-to-vigorous physical activity (MVPA) intensity.
This analysis included 4,840 participants. Increasing MVPA by 10, 20, or 30 minutes per day was associated with a 6.9%, 13.0%, and 16.9% decrease in the number of deaths per year, respectively. We estimated that approximately 110,000 deaths per year could be prevented if US adults aged 40 to 85 years or older increased their MVPA by a small amount (ie, 10 minutes per day). To our knowledge, this is the first study to estimate the number of preventable deaths through physical activity using accelerometer-based measurements among US adults while recognizing that increasing activity may not be possible for everyone. These findings support implementing evidence-based strategies to improve physical activity for adults and potentially reduce deaths in the US.