"One of the most commonly cited barriers to regular physical activity is a 'lack of time,'" says Jenna Gillen, PhD, a lead author in the study. "Our findings, however, suggest that even if you only have a few minutes to exercise, you can get a quality workout that can improve your health and fitness comparable to traditional approaches."
How Hard Do You Have to Work?
One thing to note: When it comes to short workouts, it's all about intensity. The harder you're willing to push yourself, the less time you have to invest.
"Research from our lab has shown that if you're willing to work very hard, you can get away with a surprisingly small amount of exercise," Dr. Gillen says. "We found that one-minute of hard exercise, in the form of three 20 second cycle sprints, improved cardiovascular and metabolic health in men who trained three times per week for 12 weeks."
Combine that single minute of intense exercise with a warm-up, cool-down and a few short rests and the total time commitment was only 10 minutes per session or 30 minutes each week. Yet Dr. Gillen saw similar improvements compared to groups that had worked out for 150 minutes each week. The increased intensity in the shorter workouts had made up the difference.
So what exactly counts as working "hard?"
"Aim for 80% of your maximum heart rate for the majority of your time 'on,'" Dr. Gillen says."
In other words, you want to be right at the brink of maximum effort during your workout.