A new national study has found that staying active during free time can add years to one’s life, regardless of body weight.
The finding that physical activity trumps body composition is a welcome finding to millions of individuals who struggle to lose weight even as they are physically active.
Researchers led by the National Cancer Institute (NCI), part of the National Institutes of Health found that people who engaged in leisure-time physical activity had life expectancy gains of as much as 4.5 years.
Study findings are published in the open-source journal PLOS Medicine.
For the study, researchers examined data on more than 650,000 adults. These people, mostly age 40 and older, took part in one of six population-based studies that were designed to evaluate various aspects of cancer risk.
The traditional recommendation for activity calls for adults ages 18 to 64 to engage in regular aerobic physical activity for 2.5 hours at moderate intensity—or 1.25 hours at vigorous intensity—each week, at a minimum. Vigorous activities are those during which a person could say only a few words without stopping for breath.
For even greater health benefits, many experts recommend exercising 5 hours a week at moderate intensity and that even more exercise is beneficial.
After accounting for other factors that could affect life expectancy, the researchers found that life expectancy was 3.4 years longer for people who reported they got the recommended level of physical activity.
People who reported leisure-time physical activity at twice the recommended level gained 4.2 years of life. In general, more physical activity corresponded to longer life expectancy.
However, for the many people unable to match the recommended exercise levels, the new report is positive news as researchers determined that individuals received benefits even at low levels of activity.
For example, people who said they got half of the recommended amount of physical activity still added 1.8 years to their life.
“Our findings highlight the important contribution that leisure-time physical activity in adulthood can make to longevity,” said study author Steven Moore, Ph.D., lead author of the study.
“Regular exercise extended the lives in every group that we examined in our study—normal weight, overweight, or obese.”
Demographically, researchers found that the association between physical activity and life expectancy was similar between men and women, and that blacks gained more years of life expectancy than whites.
Additionally, the relationship between life expectancy and physical activity was stronger among those with a history of cancer or heart disease than among people with no history of cancer or heart disease.
In the study, researchers also examined how life expectancy changed with the combination of both activity and obesity.
Obesity was associated with a shorter life expectancy, but physical activity helped to mitigate some of the harm. People who were obese and inactive had a life expectancy that was between five to seven years shorter (depending on their level of obesity) than people who were normal weight and moderately active.
Physical activity has been shown to help maintain a healthy body weight, maintain healthy bones, muscles and joints, promote psychological well-being, and reduce the risk of certain diseases, including some cancers.
“We must not underestimate how important physical activity is for health — even modest amounts can add years to our life,” said I-Min Lee, M.D., Sc.D., professor of Medicine, Harvard Medical School, Cambridge, Mass., and senior author on the study.
Source: NIH/National Cancer Institute