Does daily exercise cut back on older adults’ sedentary life? Study: not so much

It looks like it might be tougher than anyone thought to lure older adults away from binge-watching TV shows and other sedentary activities.

Increasing moderate-intensity exercise in older adults led to little reduction in the overall time they spent in potentially unhealthy sedentary activity, according to a study led by University of Florida Health researchers and published in the July 18 issue of the Journal of the American Medical Association.

The findings are a surprise to researchers who thought that increasing exercise would lead to overall lifestyle changes that would cut back on time spent sitting or otherwise being inactive.

“A lot of practitioners have finally accepted the fact that exercise has all these health benefits,” said the study’s senior author Todd Manini, Ph.D., an associate professor in the UF College of Medicine’s department of aging and geriatric research and a member of the UF Institute on Aging.

“Their message is to get out more and move more. And that’s a good message. We’re not saying you shouldn’t do that,’’ Manini said. “But we have to recognize that going out and exercising doesn’t necessarily budge the amount of time people are going to be sedentary in the entire day. You are not necessarily taking away from the sedentary bucket and putting it into the exercise bucket.”

The study collected data from 1,341 people, median age 79, who wore accelerometers — a device that measures movement — during waking hours at specified times during a 24-month period. The group was about evenly split, one performing moderate-intensity physical activity, the other participating in health education. All participants spent more than 10 hours a day in sedentary activities.

Adults who were inactive for periods lasting less than 60 minutes, like sitting to watch television or browsing the internet, and who engaged in moderate-intensity exercise like walking and strength, balance and flexibility training reduced daily sedentary time no more than 12 minutes when compared with a non-exercising group, the study found.

For bouts of inactivity lasting an hour or more — binge-watching territory — researchers found no benefit to exercise.

Manini said the study may point to a need for strategies beyond exercise for doctors and practitioners trying to motivate patients into more active and healthier lives. Those strategies may include convincing patients to cut back on their television time and, for younger people, getting them to get up from their desk regularly rather than sit in front of a computer all day.

Amal Wanigatunga, Ph.D., M.P.H., the study’s lead author who conducted the research while a doctoral candidate in the department of epidemiology in the UF College of Public Health and Health Professions and the College of Medicine, said studies have shown sedentary behavior leads to poorer health.

The conveniences of modern life, he said, are a resilient foe in the battle to stay healthy.

“Advances in technology that have increased automation, convenience, communication and travel promote sedentary lifestyles and have practically erased the need to engage in physical activity on a daily basis,” said Wanigatunga, now a postdoctoral fellow at The Johns Hopkins Bloomberg School of Public Health and The Johns Hopkins Center on Aging and Health.

Bill Levesque joined the UF Health staff in May 2017 as a science writer covering the Institute on Aging and research of faculty physicians in the College of Medicine.