Exercising a few times a week appears to be just as good.

January 10, 2017

Exercise is one of the best ways to avoid chronic diseases like diabetes and cancer, as well as an early death. But it can be tough to squeeze into a schedule: Health experts recommend about 150 minutes of moderate activity, or 75 minutes of vigorous, breath-sapping exercise, each week.

Since daily exercise isn't realistic for everyone, researchers decided to study whether people who tend to cram their weekly exercise into one or two days on the weekend (so-called "weekend warriors") get the same benefits as those who exercise daily. In the new research published in JAMA Internal Medicine, they found that how often a person exercises might not make a difference in determining how long a person lives.

Gary O'Donovan, a research associate in the Exercise as Medicine program at Loughborough University in England, and his colleagues analyzed data from national health surveys of more than 63,000 people, conducted in England and Scotland. People who said they exercised only one or two days a week lowered their risk of dying early from any cause by 30% to 34%, compared to people who were inactive. But what was more remarkable was that people who exercised most days of the week lowered their risk by 35%: not very different from those who exercised less.

The findings support the idea that some physical activity—even if it's less than what the guidelines prescribe—helps avoid premature death. Researchers saw benefits for people who squeezed the entire recommended 150 minutes per week into one or two days, as well as for people who didn't quite meet that threshold and exercised less.

Exercise was also effective at reducing the risk of heart-related death. The people who exercised regularly and those who exercised a couple days a week both cut their risk by about 40%. Again, the frequency of exercise didn't seem to matter.

The same was true for risk of death from cancer. Those who exercised—whether it was every day or only a few days—lowered their risk of dying from cancer by 18% to 21%, compared to those who didn't exercise. This risk reduction was true whether they met the recommended physical activity requirements or not.

"The main point our study makes is that frequency of exercise is not important," says O'Donovan. "There really doesn't seem to be any additional advantage to exercising regularly. If that helps people, then I'm happy."

The results remained significant even after O'Donovan accounted for other variables that could explain the relationship, including a person's starting BMI. In fact, the benefits were undeniable for people of all weights, including people who were overweight and obese.

That should be heartening to anyone who finds it hard to carve out time for physical activity every day. Not that you can slack off: O'Donovan stresses that his results focus specifically on moderate-to-vigorous exercise people did in their free time, and they do not apply to housework or physical activity on the job, since the surveys didn't ask about those. The study does, however, include brisk walking, which he says is a good way to start an exercise regimen for people eager to take advantage of the findings.

"This is new evidence, and perhaps guidelines have to be revisited as new evidence emerges," says O'Donovan. In the meantime, it's clear that exercise—even if it's only on the weekends—is a worthwhile addition to your routine.