Surprisingly small amounts of daily high-intensity exercise, such as climbing stairs rather taking the elevator, lugging groceries to the car, or chasing after grandchildren, may substantially cut the risk of cardiovascular disease in people who do not otherwise get much exercise, scientists say.

In a study published today in the British Journal of Sports Medicine, a team of Australian, European, and Canadian researchers equipped 81,052 middle-aged men and women (average age 61) with activity monitors that recorded their exercise levels every few seconds for an entire week. Then, they followed these people’s health for an average of eight years, looking to see who did, or didn’t, have heart attacks, strokes, or other major cardiovascular events.

In particular, they looked at people who did not otherwise exercise in an effort to determine the degree to which “incidental” exercise (which they termed VILPA, for vigorous intermittent lifestyle physical activity) affected their cardiovascular health.

They found that, after accounting for other factors such as smoking, just 3.4 minutes (204 seconds) of VILPA was enough to reduce the risk of major cardiovascular events in women by 45 percent, while as little as 1.2 to 1.5 minutes per day was enough to reduce it by 30 per cent.

In men, the effect was weaker, but non-exercisers who logged 5.6 minutes of VILPA per day were nevertheless 16 per cent less likely to have major cardiovascular events, while those who recorded at least 2.3 minutes per day still saw an 11 per cent reduction.

To people accustomed to traditional discussions of exercise, VILPA isn’t a commonly understood term. But, the study’s corresponding author, Professor Emmanuel Stamatakis, an epidemiologist at the University of Sydney, told Cosmos it’s basically exercise that’s hard enough to substantially alter your breathing. “If you can sing,” he says, “it’s light exercise. If you can talk, it’s moderate exercise. If talking is difficult, it’s vigorous.”

On average, he says, the exercise bouts lasted 20 to 40 seconds. In part, the short duration is probably due to the nature of the activities—lugging a heavy grocery bag to the car only takes so long—but it’s also because if you are not a regular exerciser, that’s long enough to get you noticeably winded.

Not that this means structured exercise isn’t even more beneficial. But VILPA offers an alternative for those unable or unwilling to go to the gym or lace up the running shoes and hit the pavement.

Why it works isn’t clear from the study. But the likely mechanisms, Stamatakis says, might be akin to those involved in high-intensity interval training (HIIT) methods used by elite athletes, which also involve short bursts of intense activity, followed by rest and recovery.

Why women get more benefit than men is less clear. “This was very puzzling,” Stamatakis admits.

One possibility is that, according to his team’s data, women’s VILPA activities, for some unknown reason, tend to be more intense than men’s. Maybe more intense is better. Another possibility is that men’s VILPA might come from work-related activity in jobs known to carry cardio-vascular risks.

Meanwhile, Stamatakis says, the study is good news for those who know they should get more exercise, but aren’t doing it.

“If you go down the street and ask 10 people, ‘Do you think exercise is good for you?’” he says, “nine-and-a-half will tell you ‘Yes, of course.’ The problem is implementation. There are many middle-aged people who have not exercised for 20, 30, or 40 years.”

Not that a single day of VILPA is going to do anyone any good. It has to become a habit, Stamatakis notes. As in, don’t just take the stairs today, but every day. Gardening, make it a point to occasionally hoe or rake vigorously. “Regularity and consistency is critical,” he says.

Amby Burfoot, former editor of Runner’s World, who now produces a newsletter summarizing the latest exercise physiology research, thinks the new study fits well with what others call “true” cardiorespiratory fitness.

“Cardiorespiratory fitness,” he says, “is more meaningful than step counts or minutes of physical activity per week.”

“You can do quite a few slow steps without getting very fit.” But, he says, a relatively small amount of HIIT (or VILPA) “can give a nice boost.”

And for non-athletes, he notes, “I don’t think many people want to do regular HIIT workouts. But a few daily stairs in the office are definitely a good thing.”

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