Second Opinion

Every bit of exercise counts in reducing risk of early death: Study

Bouts of exercise do matter to help reduce your risk of disease and premature death, cardiologists find.

'It's the total physical activity that matters,' says cardiologist and researcher William Kraus

People are encouraged to take the stairs whenever there's the opportunity, because every bit of exercise helps, according to a new study. (Shutterstock)

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There's a lot of conflicting advice out there about how much exercise is enough to stay healthy. Should you exercise three to four times a week, run a marathon or do a seven-minute workout with an app from the comforts of your living room?

It turns out they all work — even ditching the elevator for the stairwell — to help reduce your risk of disease and premature death, according to new research from the United States.

"Everything counts," said William Kraus, a cardiologist at North Carolina's Duke University School of Medicine and senior author of a new study published last week in the Journal of the American Heart Association.

The epidemiological study looked at the relative benefits of "bouted" versus sporadic moderate-to-vigorous physical activity (MVPA) on the mortality of 4,840 people who participated in the National Health and Nutrition Examination Survey from 2003-06. 

Participants in the study wore accelerometers (pedometer equivalents) to measure their daily physical activity and exertion. The researchers determined 4,140 of them were still alive in 2011, while 700 had died.

Three measures of MVPA were counted: total minutes of activity, five-minutes or more of activity and 10 minutes or more of activity. And researchers analyzed mortality associations by quartiles for the three measures.

"Does it matter whether that total physical activity was in bouts or not bouts?" Kraus said. "And we found out it didn't matter whether it was in bouts or not bouts. It's the total physical activity that matters."

The findings are good news for most Americans, who are becoming more sedentary and could break that up with short bouts of physical activity, he said.

"Take the stairs when there's the opportunity. Walk to the coffee shop instead of taking the drive-thru. Because that will all help you prevent bad health outcomes," he said. "Everything counts so take every opportunity."

The study also found that participants who got less than 20 minutes of MVPA each day had the highest risk of early death, while those who did 60 minutes a day cut their risk of premature death by more than half. Those who did at least 100 minutes a day cut their risk of early mortality by 76 per cent, according to the study.

Current federal guidelines both in the U.S. and Canada recommend at least 150 minutes of moderate aerobic exercise each week, or 75 minutes of vigorous aerobic exercise for adults.

Those guidelines recommend they should exercise in bouts of 10 minutes or more, but the study indicates this may not be necessary.

Kraus said, "It's enough we hope to kill that part of the recommendation."

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