(RxWiki News) It's not all about the pounds. People can carry a little extra but still be fit, just as slimmer people can be out of shape.
Even for people who are overweight, doing regular physical activity helps individuals live longer, according to new research.
"This finding may help convince currently inactive persons that a modest physical activity program is ''worth it'' for health benefits, even if it may not result in weight control," lead researchers said in a press release.
"Walk, bike, move!"
The study, led by Steven Moore, PhD, research fellow from the Division of Cancer Epidemiology and Genetics at the National Cancer Institute, gathered information from more than 650,000 people from five surveys that were part of the National Cancer Institute Cohort Consortium.
The studies primarily covered cancer and cardiovascular research, as well as exercise time.
Researchers tracked the hours they spent in leisurely physical activity and their body mass indexes (BMI), which calculate their height and weight together.
Leisurely activity in the study includes doing sports, walking, and exercising.
They then estimated how long each participant would live and the number of years each gained or lost depending on how active they were and their BMI. Participants were over 40-years-old and a little more than half were women. Almost all were white.
They found that people who walk briskly or do activity equal to that intensity for 75 minutes a week lived an extra 1.8 years on average compared to those who don't exercise.
Those who did 150 minutes of brisk walking a week, which is the time recommended by the World Health Organization, added about 3.4 to 4.5 years more to their lifespan.
"Physical activity above the minimal level—at recommended levels, or even higher—appears to increase longevity even further, with the increase in longevity starting to plateau at approximately 300 minutes of brisk walking per week," the authors said in a press release.
Regardless of BMI levels, doing less physical activity was linked with having a shorter life expectancy. This was still true when taking gender, ethnicity and education level into account. Further, normal weight but inactive individuals had 3.1 fewer years of life than people who are obese but active.
"A lack of leisure time physical activity when combined with obesity is associated with markedly diminished life expectancy," the authors said.
The authors note several limitations with their study, including their reliance on self-reports. Overweight and obese participants may not have accurately reported how much they exercised, or their height and weight.
They also did not examine why life expectancy increased among the more active, nor did they look at other options that could be the actual cause.
And some of the research included in their study looked at populations that may not be representative of those across the US. The Intramural Research Program of the US National Institutes of Health and the Division of Cancer Control and Population Sciences of the National Cancer Institute supported the study.
Other companies and programs that supported the study include the Intramural Research Program of the NCI, National Institute of Aging, Swedish Research Council and Swedish Cancer Society.
One of the authors was a consultant and served on the advisory board for Virgin HealthMiles. They declare no other conflicts of interest. The study was published November 6 in the journal PLOS Medicine.