Is 30 minutes of exercise a day enough?

For anyone interested in the relationship between exercise and living longer, one of the most pressing questions is how much do we really need to stay healthy? Is 30 minutes a day enough? Can we live with less? Do we all have to exercise in one session, or can we spread it out throughout the day? And when we talk about exercise, does it have to be difficult to count?

For years, exercise scientists have tried to quantify the ideal “dose” of exercise for most people. They finally reached broad consensus in 2008 with the Physical Activity Guidelines for Americans, which were updated in 2018 after a Extensive review of available science on movement, sitting and health. In both versions, the guidelines advise anyone physically able to rack up 150 minutes of moderate exercise each week, half as much if it’s intense.

But what is the best way to space out those weekly minutes? And what does “moderate” mean? Here’s what some of the top exercise science researchers had to say about step counting, stairs, weekend warriors, increased longevity, and why the healthiest step we can take is the one that gets us off the couch .

Aim for the 150-minute sweet spot

“For longevity, 150 minutes a week of moderate-to-vigorous intensity physical activity is clearly enough,” said Dr. I-Min Lee, a professor of epidemiology at the Harvard TH Chan School of Public Health. He has studied movement and health extensively and helped write the current national physical activity guidelines.

For practical purposes, exercise scientists often recommend dividing that 150 minutes into 30-minute bouts of brisk walking or a similar activity five times a week. “It is quite clear from numerous large-scale, well-conducted epidemiological studies than 30 minutes of moderate-intensity activity on most days reduces the risk of premature death and many diseaseslike stroke, heart attack, type 2 diabetes and many types of cancer,” said Ulf Ekelund, a specialist professor of physical activity epidemiology at the Norwegian School of Sport Sciences in Oslo, who has led many of those studies.

Moderate exercise, he continued, means “activities that increase your breathing and heart rate, so exertion feels like a five or six on a scale of one to ten.In other words, pick up the pace a bit if walking is your inclination, but don’t feel compelled to run.

Consider snacks for exercise

You can also break your workout into even smaller segments. “It doesn’t matter if exercise is done in one long, continuous 30-minute session or spread out throughout the day in shorter sessions,” said Emmanuel Stamatakis, an exercise scientist at the University of Sydney in Australia who studies physical activity. and health. .

Recent studies overwhelmingly Show that we can stack our weekly 150 minutes of moderate exercise in whatever way works best for us, he said. “Many people may find it easier and more sustainable to take a few dozen one- or two-minute walks between work tasks” or other commitments. “There is no special magic in a sustained 30-minute exercise session” to get the most health benefits.

think about these small workouts like exercise snacks, he said. “Activities like bursts of very fast walking, stair climbing, and carrying shopping bags provide great opportunities for movement snacks.” To concentrate the health benefits of these workout nuggets, he added, keep the intensity relatively high, so you feel a little out of breath.

Possibly, you could also focus all your exercise on long workouts on Saturday and Sunday. in a 2017 study by Dr. Stamatakis and colleagues, people who reported exercising almost entirely on weekends were less likely to die prematurely than those who said they rarely exercised. But being a weekend warrior has drawbacks. “It’s certainly not ideal to spend the workweek totally sedentary and then try to compensate” over the weekend, Dr. Stamatakis said. You miss out on many of the health benefits of regular exercise, such as better blood sugar control and improved mood, on days you don’t exercise, he said. It also increases the risk of exercise-related injuries.

count your steps

The exercise recommendations remain the same if you measure your exercise in steps instead of minutes. For most people, “150 minutes of exercise a week would translate to about 7,000 to 8,000 steps a day,” Dr. Lee said. In a new large-scale study by Dr. Lee and Dr. Ekelund on the relationship between steps and longevity, published in March in The LancetThe optimal step count for people under 60 was 8,000 to 10,000 per day, and for people 60 and older, it was 6,000 to 8,000 per day.

consider more

Of course, these step and minute recommendations focus on health and lifespan, not physical performance. “If you want to run a marathon or a 10K race as fast as possible, you need much more exercise”, Dr. Ekelund said.

The recommended 150 minutes a week may also be too little to prevent weight gain with age. in a 2010 study of nearly 35,000 women that was spearheaded by Dr. Lee, only those who walked or moderately exercised for about an hour a day during middle age maintained their weight as they aged.

So if you have the time and the inclination, move more than 30 minutes a day, Dr. Lee and the other scientists said. Usually, based on your research and other studies, the more active we are, well beyond 30 minutes a day, the more our risks of chronic disease decrease and the longer our lives can be.

But any activity is better than none. “Every minute counts,” said Dr. Ekelund. “Going up the stairs has health benefits, even if it only lasts a minute or two, if you repeat it regularly.”

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