Getting a good amount of exercise is hard work. I mean, that's kind of the point, I guess. But what counts a "good amount?" Twenty minutes a day? Or maybe an hour at the gym, three times as week? Science has spoken, and it turns out that a "good amount" is a lot less than you think. Excuse me, I'll be on the couch.
More exercise is obviously better for your body than getting less exercise, but researchers in Canada decided to check and see just how little you can get away with while still significantly benefiting your health. They took two groups of people: middle-aged and out of shape (but otherwise generally healthy) men and women, and a group of middle-aged people who had been diagnosed with cardiovascular disease. The patients were tested to determine their baseline levels of fitness, and then the fun began.
The exercise routine that the researchers asked their patients to try was interval training: short periods of very intense exercise interspersed with cool-down periods, in this case, on a stationary bike. And the training was very, very short: one minute of pedaling at 90% of maximum effort (measured by getting your heart rate up to 220 beats per minute minus your age), followed by one minute of easy pedaling, repeated 10 times. This 20 total minutes of exercise was done twice a week, and that was it.
After just a few weeks of this routine, everyone in the study (but especially the cardiac patients) showed "significant improvement." Their bodies produced lots more more cellular proteins involved in energy production and oxygen and improved their insulin sensitivity and blood sugar retention, lowering risk of Type 2 diabetes. And while it was hard work, it was very brief hard work, and a lot easier for people to manage (physically and psychologically) than a more traditional exercise routine.
For the record, the American Heart Association has been recommending 30 minutes of moderate-intensity exercise five times a week, for a total of two and a half hours of weekly misery. But this research suggests that it may not be necessary to spend every weekday at the gym, as long as you're clever about what kind of exercise you're getting. There's nothing wrong with getting more exercise, and it's definitely good for you, but if you're short on time (or willpower) it now seems that you can still get some significant health benefits with just 20 minutes per week of actual hard work.