Its findings suggest that even small amounts of exercise contribute to substantial improvements in longevity and reduce the risks of developing or dying from heart disease and many types of cancer.
“The investigators took a comprehensive look at the available evidence and came up with encouraging findings,” said Ai-Min Lee, a professor of epidemiology at the Harvard TH Chan School of Public Health, who was not involved in the new study.
Perhaps most encouraging, the study’s statistical analysis suggests that 1 in 10 of all early deaths could be avoided if each of us got up and moved a little more than many of us currently do.
150 minutes and 75 minutes per week
For years, government health agencies in the United States, Canada, Europe, and other countries have recommended that anyone who can exercise should do at least 150 minutes of moderate exercise per week for optimal health. (Moderate exercise can be a brisk walk or breathing that raises your heart rate and makes conversation difficult.)
In practical terms, these guidelines encourage brisk walking for half an hour five times a week.
But according to most of us, no Latest federal statisticsThis shows that only 47 percent of American adults get enough exercise.
That sobering statistic has prompted some researchers to look at the effects of even small amounts of exercise. However, most research involved relatively small numbers of people, making broad conclusions about optimal levels of exercise elusive.
Therefore, for the new study, researchers from the University of Cambridge, Queen’s University Belfast and other institutions decided to pool data from as many relevant past studies as possible, which would create a much larger pool of participants and produce more definitive results.
They conducted 196 studies, involving more than 30 million people, making it the “biggest” study of how exercise contributes to longevity, with multiple measures and a huge difference, Leandro Garcia said. Garcia is a public health and complexity researcher at Queen’s University Belfast who led the new study.
A little more movement is a big gain
What the pooled data showed was that 150 minutes of moderate weekly activity should be our exercise lodestar. Those who managed more labor were 31 percent less likely to die prematurely than those who were inactive.
But the researchers also observed the effects of less movement, as two-thirds of the more than 30 million participants did not exercise that much. Boldly, the implications were huge. Men and women who got 75 minutes of moderate exercise a week, or only about 11 minutes a day, were 23 percent less likely to die prematurely from any cause than those who were less active.
Those 11 daily minutes of exercise cut people’s risks of heart disease by 17 percent and any type of cancer by 7 percent. For some cancers, including myeloid leukemia, myeloma and some stomach cancers, the risk decreased by up to 26 percent.
Scientists used statistical modeling to estimate that if almost everyone exercised 150 minutes a week, following current guidelines, 16 percent of all premature deaths, or 1 in 6, would not occur.
They concluded that even if everyone walked 11 minutes a day, 1 in 10 early deaths could be avoided.
“It’s already known that doing some physical activity is better than doing nothing,” Garcia said. “However, due to the comprehensive nature of our study, we were able to establish this association more precisely.”
In fact, “the biggest bang comes from when someone goes from doing nothing to doing even half the recommended amount,” Lee said.
Despite its size and rigor, the study has meaningful limitations. It shows links between greater mobility, longer life and less disease, but not whether exercise directly causes those gains. Other factors, such as genetics and income, probably play larger roles. The pooled studies also rely on people’s memories and reports of how much they exercise, which can be unreliable.
But even with those drawbacks, the findings provide a useful stimulus, Garcia said. “Adding physical activity to your daily routine doesn’t have to be daunting,” she said. “Small and gradual changes are a great starting point and can bring many health benefits.”
Park a short distance from your office, he said. Go up the stairs. Dance around the living room with your kids.
Ideally, aim to start with about 11 minutes of moderate movement per day, and if you find that amount “manageable,” “try to gradually increase it to the full recommended amount” of 150 minutes per week, she said. But in any case, he said, “doing some physical activity is better for your health than doing nothing at all.”
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