(Reuters Health) - While regularly exercising over the course of decades is a great way to live longer, a U.S. study suggests that even people who don’t start working out until middle-age may see similar longevity benefits.
To help people live longer, national guidelines for physical fitness recommend that adults get at least 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous exercise each week. But much of the evidence behind these recommendations has looked at exercise at only one point in time, leaving a murky picture of how lifelong exercise habits might impact longevity, researchers note in JAMA Network Open.
For the current study, researchers examined data on 315,059 adults ages 50 to 71 who completed surveys about their exercise habits from adolescence through the most recent decade. During an average follow-up of almost 14 years, 71,377 people had died, including 22,219 from heart disease and 16,388 from cancer.
Compared to people who were inactive throughout their lives, participants who reported consistently high levels of exercise from youth through middle age were 36 percent less likely to die of any cause during the study period.
But the benefit was similar when inactive people got moving only when they were between 40 and 61. When previously sedentary people started exercising in middle age, they were 35 percent less likely to die of all causes during the study than if they remained inactive.
“We were very pleased to see that individuals who increased their exercise participation only later in adulthood still enjoyed the health benefits associated with exercise participation,” said study leader Pedro Saint-Maurice of the National Cancer Institute in Bethesda, Maryland.
“These findings suggest that if you’re active in early adulthood, stay active - don’t decrease,” Saint-Maurice said by email. “If you’re in your 40-60s and you have not been active for a long time, it’s not too late to start exercising now.”
Overall, about 56 percent of participants consistently exercised throughout their lives. Another 31 percent started strong but tapered off over time; and 13 percent were inactive early in life but got moving later on.
Compared to people who were always inactive, participants who consistently exercised were 42 percent less likely to die of heart disease and 14 percent less likely to die of cancer, the study found.
When people started out inactive but got moving later on, they were 43 percent less likely to die of heart disease and 16 percent less likely to die of cancer than if they remained sedentary.
The study doesn’t prove whether or how exercise might help people live longer, and the researchers say it’s possible that healthier people were more likely to exercise. The study also didn’t examine what types of workout, or what intensity or frequency of exercise, might be ideal.
“The take-home message is that physical activity is important for a healthy and long life,” said Dr. Per Ladenvall of the Institute of Medicine, Sahlgrenska Academy at Gothenburg University in Sweden.
While current guidelines call for at least 150 minutes of moderate workouts or 75 minutes of intense exercise per week, they also suggest that more is better, Ladenvall, who wasn’t involved in the study, said by email.
“The same guidelines acknowledge that additional health benefits can be achieved in aerobic physical activity up to 300 minutes a week of moderate intensity, or 150 minutes a week of vigorous intensity aerobic physical activity,” Ladenvall said.
But people shouldn’t do too much too soon, Ladenvall advised.
“It is also recommended for sedentary people to increase their physical activity gradually.”
SOURCE: bit.ly/2XMHLkB JAMA Network Open, online March 8, 2019.