Leisure-time physical activity is associated with longer life expectancy, even at relatively low levels of activity and regardless of body weight, according to a study.
To determine the number of years of life gained from leisure-time physical activity in adulthood, researchers examined data on more than 650,000 adults. The cohort mostly was age 40 and older and took part in one of six population-based studies that were designed to evaluate various aspects of cancer risk.
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 getting the recommend level of physical activity (2.5 hours a week of exercise at moderate intensity or 1.25 hours at vigorous intensity). 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.
The researchers observed benefits even at low levels of activity. For example, people who said they got half 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,” study author Steven Moore, PhD, of the National Cancer Institutes Division of Cancer Epidemiology and Genetics, said in a news release.
“Regular exercise extended the lives in every group that we examined in our study — normal weight, overweight or obese.”
The researchers found the association between physical activity and life expectancy was similar between men and women, with blacks gaining more years of life expectancy than whites. The relationship between life expectancy and physical activity was stronger among those with a history of cancer or heart disease.
The 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,” said I-Min Lee, MD, ScD, professor of medicine at Harvard Medical School. “Even modest amounts can add years to our life.”
The study appeared Nov. 6 in the online journal PLOS Medicine and is available at http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1001335.