What good is a 5 minute workout anyway?

A few lucky people find a fitness routine they love and stick to it. But many of us just want to get our training over with as quickly as possible. For those in the latter camp, it’s hard to resist the headlines that claim we can get into shape in five minutes or less a day.

Sounds too good to be true, but emerging research suggests these micro workouts — a few 20-second laps of stair climbing, four-second sprints on a stationary bike, or a two-minute run around the bus — can improve fitness, prevent disease and prolong one’s life.

These activities fit into your schedule more easily than the recommended 150 minutes of moderate weekly exercise (or 75, if you make it vigorous, such as by running). However, some scientists say such micro-workouts, also known as exercise snacks, are oversold. And even those who tout their benefits claim they are as good or better than more traditional workouts, which go too far.

What is the evidence for the micro workout?

The concept builds on more than two decades of research into HIIT, or high-intensity interval training. HIIT involves a series of near-all-out efforts, usually 20 to 60 seconds long, interspersed with short rests, and then repeated over and over again. Some studies suggest that HIIT workouts provide many of the same benefits as regular moderate-intensity exercise – including improved aerobic fitness and blood vessel function – in less time.

So researchers wondered whether just a few hard intervals spread throughout the day would be effective. Can short bursts of activity still have benefits with hours of rest in between instead of seconds?

So far, small laboratory studies have suggested that micro workouts may influence certain health measures. In a typical example, twelve young adults who otherwise did not exercise ran up three flights of stairs (60 steps) three times a day, three days a week. After six weeks, their aerobic fitness, measured by oxygen intake, had disappeared improved by five percent. This is about what you would expect from three days of brisk walking for 30 minutes per week, said Jonathan Little, the study’s lead author and a professor at the University of British Columbia.

Another study of more than 25,000 British adults found that just one to two minutes of vigorous exercise three times a day was associated with a roughly 40 percent lower risk of death, and about a 50 percent lower risk of dying from cardiovascular disease compared with people who didn’t do vigorous exercise. activity performed.

But observational studies like these cannot prove cause and effect. And that advantage is less robust than what you would expect from those who meet government exercise guidelines. Still, such short bursts, if done regularly and safely, can provide a meaningful start for people who otherwise lead sedentary lives, says Emmanuel Stamatakis, a professor at the University of Sydney and lead author of the study.

Why are some scientists skeptical?

Exercise makes us fitter and healthier by putting stress on our muscles and cardiovascular system, which then become stronger and more efficient, said Dr. Philip Skiba, an exercise physiologist and physician in Park Ridge, Illinois. Minute by minute, intense efforts stimulate muscles more than moderate workouts — but bursts of just 20 seconds are unlikely to produce major health improvements, he said.

In fact, even the benefits of HIIT can be blown up, says Panteleimon Ekkekakis, professor of exercise psychology at Michigan State University. Most laboratory studies of short but intense exercise are small, limiting their statistical power. Outside the laboratory, wrist-worn activity monitors allow for studies of larger groups of people, but may not capture accurately factors such as intensity, especially for short periods.

Plus, while you study to suggest While intense intervals are safe even for people undergoing cardiac rehabilitation, strenuous exercise can in some cases raise the risk of sudden heart problems. So it’s wise to consult your doctor first if you have a history of heart problems or have been sedentary for years, Dr. Skiba said.

Finally, micro-workouts may not actually motivate people to exercise, said Dr. Ekkekakis; research indicates Lack of time is actually not the biggest barrier. A more important point, he said, is that many people don’t enjoy it, especially when they’re just starting out. And intensive training are often more unpleasant then moderate.

it comes down to

Intense bursts of exercise for five minutes or less one or more times a day are likely to provide some benefit, especially if you really have no other time to exercise or if you spend long stretches confined to your chair.

More research is currently being done on the optimal “dose” – how many bursts you need, and how long and hard they should be, to produce meaningful changes in your health, said Dr. Little.

However, decades of research, with many thousands of participants, more clearly support the health benefits of about 150 minutes of moderate activity or 75 minutes of vigorous exercise per week. So what you shouldn’t do is replace any other type of exercise habit – especially one you enjoy – with micro workouts.

“That would be a real risk based on what we currently know,” said Dr. Skiba.