The only reason why people don't work out is because they're lazy. It'll take up some time to do so, but according to a new study in the Journal of Physiology, it suggests that you might be able to get all the exercise in 20 minutes if you are willing to get off your lazy ass.

The New York Times reports that a group of researchers are turning health and fitness studies on its head, by investigating just how little exercise we really need. Professional athletes usually do short, sharp bursts of strenuous activity gets interpersed with rest and using that, researchers at McMaster University developed a version of high intensity interval training that involves one minutes of strenuous effort at 90 percent of a person's maximum heart rate, followed by one minute of easy recovery.

Repeat this process ten times, which is a total of 20 minutes. And carry this out, twice a week. Researchers have shown that after several weeks of practicing it, both unfit volunteers and cardiac patients taking part in the study showed significant improvements in their health and fitness.

We've talked briefly about interval training before, but this is one of the first studies to dig into if it actually works as a replacement for the usual recommendation of 30 minutes of continuous exercise. The idea is simple. You workout for one minute with strenuous activity and push your heart rate to about 90 percent of it's maximum rate. You can get a rough estimate of your maximum heart rate by subtracting your age from 220. After the minute is up, you slow down and recover for one minute. You then repeat this 10 times for a total of 20 minutes (or 10 minutes of actual exercise). You can use this for running, cycling, swimming, or any number of cardiovascular workouts. (Note that this isn't exactly the same as traditional high-intensity interval training, in which you push to 100 percent of your maximum heart rate.)

Journal of Physiology via New York Times