Physical Activity Lowers Risk of 5 Common Chronic Diseases

Higher levels of activity were associated with a significantly lowered risk for outcomes in 5 common chronic diseases; however, the largest gains were made at lower levels of activity with diminishing gains as activity levels increased, according to a study published in The BMJ.

Based on previous studies on the health benefits of physical activity, the World Health Organization has recommended at least 600 metabolic equivalent (MET) minutes of total activity per week, which is the equivalent of walking briskly for 150 minutes a week or running 75 minutes a week.

“Despite the well established causal relations between physical activity and chronic diseases, including breast cancer, colon cancer, diabetes, ischemic heart disease, and ischemic stroke, knowledge is limited as to how much the risk decreases with an increase in the amount of total activity,” the authors wrote.

The authors analyzed studies from 1980 to 2016 that examined the association between physical activity and the risks of 1 of the 5 outcomes. Of the total citations, the authors included a total of 174 relevant studies.

While the researchers determined that higher levels of activity were associated with lower risk of all outcomes, the major gains occurred at lower levels of activity. Individuals with the lowest activity level recommended (600 MET minutes/week) had a 2% lower risk of diabetes compared with people reporting no physical activity. Risk was reduced an additional 19% when MET minutes/week increased from 600 to 3600. Risk reduction occurred at smaller levels after that. For example, an increase in total activity from 9000 to 12,000 MET minutes/week only reduce the risk of diabetes by 0.6%.

The researchers also found that the pattern for risk reduction was most prominent for ischemic heart disease and diabetes and least prominent for breast cancer.

Overall, the researchers determined that most health gains occurred at 3000 to 4000 MET minutes/week. This level of physical activity can be reached by incorporating a variety of activities into daily routines. The authors provided the following example of daily additions that would reach the 3000 MET minutes/week minimum: climbing stairs for 10 minutes, vacuuming for 15 minutes, gardening for 20 minutes, running for 20 minutes, and walking or cycling for 25 minutes.

The study’s findings suggest that total physical activity should actually be several times higher than the current recommended minimum in order to achieve large reductions in the risks for these chronic diseases.

“With the population ageing, and an increasing number of cardiovascular and diabetes deaths since 1990, greater attention and investments in interventions to promote physical activity in the general public is required,” the authors concluded.