Why Physical Activity Is the Best Predictor of Mortality

Many physicians view smoking and various chronic diseases as the key contributors to a shortened lifespan, report Erjia Cui, PhD, and his team in Medicine & Science in Sports & Exercise. But after reviewing data compiled in the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014, they concluded that clinicians should look more carefully at the number of steps their patients are taking each day.

Throughout the survey, the 3,653 NHANES participants wore accelerometer devices on their wrists to measure their physical activity (PA). That data provided a more accurate prediction of the participants’ mortality during a five- to eight-year follow-up period than any other indicator.

“These results suggest that PA monitoring may provide more sensitive insights into health status and mortality risk than traditional clinical assessments,” notes Cui, an assistant professor at the University of Minnesota School of Public Health.

He acknowledges the study has some limitations: It focused on the predictive value of monitoring physical activity and omitted some variables that would have meaning in a clinical or scientific setting. As a result, the findings suggest a correlation, rather than causation, between more physical activity and greater longevity.

Still, Cui believes the message to people of all ages is a powerful one.

“Moving more will benefit your long-term health,” he says. “Encourage yourself to increase daily activity, and if you have a wearable device like a Fitbit or Apple Watch, look at the numbers. They actually matter.”