Why moving fast three minutes a day can lower your cancer risk

Run to catch the bus and you might also help to lower your risk of developing at least 13 types of cancer, according to a surprising new study in JAMA Oncology.

The study used activity-tracker data for more than 22,000 men and women to show that those people who moved fast for at least 3 minutes a day, rushing up the stairs or hurrying to the subway, were about 30 percent less likely to die of many types of cancer than people who almost always strolled gently from place to place, even if none of them otherwise exercised.

"This is an impressive analysis and study," said Susan Gilchrist, a former professor of cardiology at MD Anderson Cancer Center in Houston who now consults for the institution. She has studied cancer risk and exercise but wasn't involved with the new research.

The study builds on past data indicating that vigorous exercise, the kind that increases our breathing until we feel quite winded, might help protect us against cancer.

But the study also suggests formal exercise may not be needed to gain those benefits. It could be enough just to pick up the pace of activities we'd be doing anyway.

Exercise and cancer risk

Even before this study, science showed strong links between physical activity and reduced cancer risk. In a large-scale, 2016 scientific review in JAMA Internal Medicine, researchers found that the likelihood of developing 13 common cancers, including breast, stomach, bladder, colon and blood cancers, was much lower if men and women exercised regularly. A 2022 analysis concluded that 46,356 annual cancer cases in the United States, or about 3 percent of all cases, might be prevented if everyone who doesn't currently exercise started.

But most of this research involved people working out for at least 30 minutes or more almost every day, which is the minimum amount recommended by federal health agencies. A majority of Americans don't exercise that much.

So, some scientists began looking into whether less exertion might still lower cancer risk, and, if so, how little and what types?

Those questions led Emmanuel Stamatakis, a professor of physical activity, lifestyle and population health at the University of Sydney in Australia, and his colleagues to consider VILPA, an acronym for Vigorous Intermittent Lifestyle Physical Activity, which refers, in essence, to what we do when we're about to miss our train.

How to sneak intensity into your life

Vigorous exercise is known to potently increase fitness - more so, minute by minute, than moderate activities, like brisk walking. As a result, it improves health as much as or more than other, easier exertions, in less time.

But if few of us exercise often, even fewer of us willingly exercise intensely.

Stamatakis and his colleagues wondered: Might we, though, gain almost comparable benefits if we sometimes move fast in our normal lives, without trying to actually exercise?

In a widely discussed study published last year in Nature Medicine, he and his colleagues decided, yes, it seems we can.

That study analyzed accelerometer data from more than 20,000 people to conclude that people who moved vigorously for at least four minutes a day, but were otherwise inactive, were about 30 percent less likely to die prematurely from cancer or other causes than people who never picked up the pace.

But that study focused on cancer mortality, not cases, although avoiding cancer is preferable to surviving it.

So, for the new study, most of the same researchers looked at whether occasional mad dashes to reach the elevator or subway might influence our risk of developing cancer in the first place.

Lowering your cancer risk by rushing

As in their earlier study, they mined data from the UK Biobank, a repository of health information for hundreds of thousands of British adults, some of whom wore accelerometers to track their daily movements.

The researchers pulled records for middle-aged and older people who had worn activity trackers and said they never exercised. They then used artificial intelligence to analyze the data, breaking down people's movement patterns second-by-second to find when they scampered, rushed or sped.

Next, they checked medical records for cancer diagnoses in the subsequent seven years or so, paying special attention to diagnoses for the 13 cancers previously identified as less common among active people. Finally, they calculated people's cancer risks.

It turned out that any VILPA reduced the risk for cancer.

"The minimum needed to see some risk reduction was well under one minute a day," Stamatakis said.

The 3-minute sweet spot

But the sweet spot seemed to hover at around three to four minutes a day of hurrying places - not exercising, just hurrying. That small amount of vigorous movement was associated with about 18 percent less risk of developing cancer of any type, while the likelihood of developing one of the 13 cancers of special interest was almost 30 percent lower.

The risks continued to drop if people accumulated more VILPA, but at a slower rate.

"These findings are provocative," said Kathryn Schmitz, a professor of exercise oncology at the University of Pittsburgh Medical Center's Hillman Cancer Center who studies exercise and cancer but was not involved with the new study.

She cautions, though, that convincing people to move intensely, even for a few moments, is likely to be daunting.

"People tend to prefer light-intensity activity," she said.

But Stamatakis is optimistic. "Our study's findings are especially pertinent to people who are not keen on leisure-time exercise," he said, "which is the majority of the adult population. For them, our study suggests that doing a few short bursts of intense exercise as the day goes by may be beneficial."

The results don't mean that those of us who exercise should quit and substitute a quick sprint or two, Stamatakis added. They also show correlations but not whether VILPA directly causes cancer cases to drop, or how it might protect against cancer. Changes in our fitness, immune systems and bodily inflammation as a result of the activity probably play a role, Stamatakis said.

"The take-home message is that moving more at a higher intensity during everyday living may be a good alternative to structured exercise," he said, "and may reduce cancer risk in the long term."