Forget eight-minute abs, six minutes is enough exercise

In the human world, this rat water torture is known as interval training, and Canadian scientists now believe that similar results can be achieved in humans, says a New York Times report last week.

In other words, you may be wasting your time doing long runs, swims, bike rides, etc…when all you need to do is exercise hard and have breaks over, maybe, a few minutes.

The Times’s Gretchen Reynolds quoted Martin Gibala from McMaster University in Ontario arguing that endurance-type exercises may not be the only way to build up physical fitness. A similar result, he thinks, may be possible with much more intense, but shorter work-outs.

Gibala has been working up this theory for years and he’s not alone. Researchers at the University of NSW have also seen benefits – and more of them in a moment.

But first, Gibala: in 2006 he published work showing how he’d tested 16 people to check on benefits of interval training on endurance. Eight did nothing different and the other half had between four and seven 30-second bursts of intense cycling followed by four minutes of recovery. This was repeated three times a week for two weeks.

Endurance for the exercise group almost doubled, from 26 minutes to 51 minutes, while the do-nothing people saw no improvement.

In his most recent work, Gibala told the Times he’d set up two groups. This time, both sets actually did some exercise. The first rode a stationary bike for between 90 minutes and two hours, while the other engaged in strenuous bursts of cycling for up to 30 seconds.

The intensity was as tough as the rider could stand, and was followed by a four minute rest. This was repeated up to six times.

After two weeks, and three sessions a week, the endurance of the two groups were both found to have similarly increased. The difference, though, was that one had worked out for five hours a week, and the other for 6-9 minutes.

The notion you can get this bargain basement type of fitness, however, isn’t quite the full story. As bloggers like Bethany Sanders on thatsfit.com noted, it’s not as simple as it sounds.

“While interval training is a fantastic way to blast fat, it’s not as simple as speeding up from a walk to a jog every 20 seconds. Efficient intervals—they have to hurt. In fact, during those sprints, you should be working at 90 percent effort. In other words, according to this perceived exertion scale (which happens to be my favourite), you should be thinking, “I’m probably going to die.”

OK, we don’t want you to die, of course. But the point is … not every exercise or exerciser is suited to this kind of workout. Runners, for instance, might find themselves with injuries pounding the pavement. But indoor cycling lends itself well to intervals.”

Australian researchers have also found some amazing benefits from interval training, this time in burning off fat rather than building endurance.

That work, at the University of NSW in 2007, studied overweight women, and gave them a 20 minute cycling regime in which they sprinted on a stationary bike for eight seconds followed by 12 seconds of cycling lightly.

The result was that the first group lost three times as much fat as the other women, who exercised at a continuous and regular pace for 40 minutes, according to Steve Boutcher, an associate professor and head of the Health and Exercise Science program.

Boutcher, in reporting his findings, argued it was all due to a “unique metabolic response” in the body.

Intermittent sprints produced high levels of catecholamines, which allowed more fat to be burned.

Most weight came of the legs and bottom, which was unusual, since Boutcher said most exercise produced weight loss across the body. Recommended exercises included swimming, walking, running and rowing.

If all this is true, then there are no more excuses. We can can get fit and burn off fat in next to no time. We’ll just have to feel like we’re dying to do it.