If you're like most Americans, Australians, and Brits, you're not getting nearly enough exercise, and we probably don't have to tell you what that's doing to your body. No one wants to be unfit, but life just happens, working out is boring, does waving my legs around under my desk count?
It's so easy to ignore the science and ditch exercising in favour of doing just about anything else, but a new study has found that 1 minute of intense exercise is all you need to get the same benefits of a more moderate 45-minute session.
"This is a very time-efficient workout strategy," says exercise physiologist Martin Gibala from McMaster University. "Brief bursts of intense exercise are remarkably effective."
First off, a caveat: 1 minute of intense exercise does not mean 'start, 60 seconds of exercise, finish'. All up, the routine will take you 10 minutes, which includes warming up and cooling down, but really, it's 10 minutes. Everyone has 10 minutes.
Gibala and his team recruited 27 men who don't typically exercise, and assigned them three weekly sessions of either intense or moderate training for 12 weeks, or to a control group that did not exercise at all.
The 'intense' exercise group were shown how to perform sprint interval training (SIT), which involves a 2-minute warm-up on the bike, then three 20-second cycle sprints, followed by a 3-minute cool-down session and 2 minutes of easy cycling.
The 'moderate' training group had to get on a bike and ride continuously at a moderate pace for 45 minutes three times a week.
The scientists examined key health indicators in all groups over the course of the experiment, including cardiorespiratory fitness and insulin sensitivity, which determines how well the body is regulating blood sugar levels.
Interestingly, though the moderate group had done five times as much exercise as the SIT group over the 12-week period, the health benefits they experienced were "remarkably similar", the team reports.
"Most people cite 'lack of time' as the main reason for not being active," says Gibala. "Our study shows that an interval-based approach can be more efficient - you can get health and fitness benefits comparable to the traditional approach, in less time."
The results have been published in PLOS ONE, and while we should point out that 27 men isn't the greatest sample size, they do mirror what an increasing body of research has been hinting at - long-distance and endurance-style exercises probably have limited benefits for the average human.
Yep, that's right - there's such a thing as too much exercise, and it's surprisingly easy to get to that point if you're a bit of a health nut.
Studies have shown that while regular exercise can add six years to your life, that benefit can disappear once you're clearing more than 48 km (30 miles) per week, and as Matthew Mientka reports for Medical Daily, improvements to blood pressure, cholesterol levels, and cardiac health appear can be offset in some people at least partially by the negative effects that can result from too much exercising.
Heart disease in particular is a concern for endurance exercises, with atrial fibrillation (abnormal heart rhythm), plaque formation in the coronary artery, and aortic aneurysms having been reported in long-distance athletes.
It's complex, because every body responds to exercise differently, but the message is that you don't need to give up several hours of your week to ensure a healthy lifestyle.
"I don't want anyone to read that exercise can be bad for you," John Mandrola, a cardiac electrophysiologist from the Baptist Hospital East in Louisville, told Mientka. "Some folks do tonnes of exercise and are protected. Some folks probably have some individual susceptibility to it. I'm a big believer in short intervals of high intensity."
So get your skipping rope or treadmill out and go to town for 10 minutes. Here's some awesome science videos to keep you company.