You may be wondering, “3 minutes of intense exercise is enough? How is that possible?” Most of us have been told over and over that the only way to get fit is to spend hours every week working out, running, jogging, cycling, and training. The US government recommends a minimum of 150 minutes of exercise per week. So how are just three minutes of intensity anywhere near enough?
According to research from McMaster University, just one minute of very intense exercise (supramaximal exercise) in a time commitment of 10, three times a week, can offer health benefits on par with longer periods of jogging, cycling, elliptical training and other traditional endurance (read: low intensity) training. Spending just a few minutes of running or cycling at 100% intensity was shown to be just as effective in improving cardiorespiratory health in the subjects as 150.
The researchers gathered 27 sedentary men and divided them into three groups: control (no exercise), moderate-intensity endurance training (MICT), and Sprint Interval Training (SIT). The study lasted for 12 weeks, during which time the various participants engaged in their respective training protocols. At the end of the study, the researchers measured the fitness results to see which group showed the most improvement.
The SIT protocol consisted of 3×20-second ‘all-out’ cycling effort, separated by 2 minutes of low-intensity cycling. The MICT protocol consisted of 45 minutes of continuous cycling at moderate intensity. A 2-minute warm-up and 3-minute cooldown of low intensity were included, resulting in 10- and 50-minute sessions for SIT and MICT, respectively. To accommodate progression, training loads were adjusted to maintain the desired relative exercise intensity.
Here’s the strange thing: both groups showed similar improvement. The moderate intensity group spent 45 minutes cycling at a continuous, low-intensity pace, while the SIT group spent just 10 minutes training—including five minutes for warm-up and cool down, meaning just five minutes actually training. But the fact that they went all out (95 to 100% VO2 Max) is what yielded such impressive results.
The findings put to rest the common excuse for not getting in shape: there is not enough time.
“This is a very time-efficient workout strategy,” says Martin Gibala, a professor of kinesiology at McMaster and lead author on the study. “Brief bursts of intense exercise are remarkably effective.”
The interval-based approach to your training is far more effective (for your cardiorespiratory health) than endurance or moderate-intensity training. Not only do you get in and out of the gym faster, but the benefits are the same. You can also increase your aerobic and anaerobic thresholds, which can lead to better performance in all areas of fitness.
Effect of SIT and MICT on VO2peak. Measured at baseline (PRE), 6 weeks (MID), and 12 weeks (POST) in MICT, SIT and control groups.
Gibala, who has studied interval training for more than a decade, was the first researcher to show that a few minutes per week of intense exercise produced benefits similar to longer, continuous workouts. Over time, his team has experimented with different protocols in an effort to identify the most time-efficient exercise strategies.
“The basic principles apply to many forms of exercise,” he says. “Climbing a few flights of stairs on your lunch hour can provide a quick and effective workout. The health benefits are significant.”
Still, there has to be a reason why people don’t even do that little amount of exercise that has a proven benefit. According to a Harvard Medical School article on why people become overweight, a number of factors are prevalent in people who don’t exercise.
- Sedentary Practices – devices and TVs. Our lives are dominated by screens that keep us occupied, give us bad posture and add negatively to our sense self-worth. We also tend to be prone to making choices like driving somewhere when we could walk or taking an elevator when we could have used the stairs.
- Stress – most Americans work longer hours, take fewer vacations, and tend to leave stressful lives. A life that is always-on-the-run doesn’t lend itself to healthy practices.
- Environment – imagine how the next generation of kids is growing up today with parents who are sedentary and stressed. Their childhood environment is going to enforce habits and reactions that will probably create even more sedentary and stressful behavior.
Genetics does play a role in pre-determining your propensity to be overweight, but ultimately modern life seems to be the detriment to positive motion when it comes to taking care of yourself. Maybe it’s time we rethink the very things that have made us too comfortable and less active – starting with screen time. Each successive generation is in danger of becoming even more mired in lifestyle choices that are, to put it bluntly, a death sentence.
1. Jenna B. Gillen, Brian J. Martin, Martin J. MacInnis, Lauren E. Skelly, Mark A. Tarnopolsky, Martin J. Gibala. “Twelve Weeks of Sprint Interval Training Improves Indices of Cardiometabolic Health Similar to Traditional Endurance Training despite a Five-Fold Lower Exercise Volume and Time Commitment.” PLOS ONE, 2016; 11 (4): e0154075 DOI: 10.1371/journal.pone.0154075.