If something sounds too good to be true, it probably is.
Yesterday (April 26), researchers at McMaster University in Canada published a study that short, sprint workouts could be just as beneficial to your health as longer, moderately intense workouts. News outlets including the New York Times were quick to report that “one minute of all-out exercise may have benefits of 45 minutes of moderate exertion.”
Unfortunately, for those of us who feel pressed for time, it’s probably not that simple.
The study looked at 26 men who did not exercise at all. They were divided into three groups: One group did 10 minutes of cycling with three 20-second high intensity bursts; another did moderate cycling for 45 minutes; and those who did no exercise at all. The groups did these exercise routines three times a week for 12 weeks. Researchers found that both groups of men who exercised experienced about the same health benefits: they were able to take in more oxygen during exercise and remove blood sugar from their bodies more quickly than before.
But it doesn’t take into account the myriad benefits of exercise, explains Karen Smith, a dietician at Barnard Medical Center and personal trainer. “It is only showing the physical benefits to exercise, and we know that there are other benefits as well, especially mental [health] benefits,” she said. Exercise releases endorphins, a chemical in the brain makes us feel less stressed, and can boost our moods and may help prevent some mental health problems, like depression.
Cycling also doesn’t benefit our skeletal systems the way other types of exercise do. “Riding a bike…is not weight-bearing exercise,” she said. Weight-bearing exercises are those which require us to carry our weight, like walking, running, or yoga. These types of exercises ultimately help build up bone density, a lack of which can lead to osteoporosis later in life.
Additionally, because the population being tested wasn’t exercising to begin with, they were bound to see some results either way, Susan Levin, also a registered dietician, said in an email. “You would expect to see more dramatic outcomes in any exercise change (or dietary for that matter) than you would in healthy, physically active people.”
That’s not to say that this study lacks merit entirely: “For people who are currently sedentary, it may possibly motivate them to do some activity,” Smith said. “Maybe if they see benefits from doing 10 minutes of exercise, it could lead to them increasing them to do it for 15 or 20 minutes.”
And, she adds, if you exercise on a regular basis but find yourself traveling or otherwise unable to squeeze a longer workout in, taking 10 minutes with some high-intensity training can be a quick substitute.
Although one minute of high-intensity training has some health benefits for sedentary populations, it’s probably too soon to say it can replace longer, moderate exercise for everyone. The US Centers for Disease Control recommends that healthy adults get at least two and a half hours of moderate activity, like brisk walking, or one hour and 15 minutes of intense activity, like running, plus two days of strength training, per week.
Smith said that ultimately, the best exercise you can do is one that you actually enjoy doing, so that you’re more likely to maintain a regime in the future.