With more active lifestyle, average adult could live 5.3 years longer

Americans over age 40 could live an extra 5.3 years if they were as active as the top 25% of the population, according to recently published research in the British Journal of Sports Medicine.

To calculate life expectancy tied to physical activity levels, researchers used a multipart analysis of existing data. They created a demographic tool using 2017 mortality data from the National Center for Health Statistics and plotted life expectancy tied to activity level.

After that, the researchers used estimates from the 2003 to 2006 National Health and Nutrition Examination Survey, a sample of noninstitutionalized U.S. civilians, to plot population levels of physical activity.

The researchers converted differences in all measured physical activity levels to the equivalent hours of walking. This allowed them to convert all types of activity to a common metric and determine how many hours of life could be gained by the average additional hour of walking at 3 mph. The researchers said the most active group put in the equivalent of 160 minutes a day of walking at 3 mph, while the least active were active for the equivalent of walking 49 minutes a day.

According to the results, if all Americans age 40 years and older were as active as the least active group, life expectancy would be 73 years, almost six years shorter than the 2017 average. Moving up to the second and third quartiles of activity would increase life expectancy by over a half-year and 3.5 years, respectively. Going from the least active to most active group could increase life expectancy by almost 11 years.

The least active Americans had the most to gain: With one extra hour of walking, individuals in the lowest activity quartile could add six hours to their lives, the study found.