20-Second Workout: Is ‘Fast Exercise’ the Best Thing for You?

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20-Second Workout: Is ‘Fast Exercise’ the Best Thing for You?

In an age of instant gratification where we want everything fast, from fast food to fast fashion, we expect the same from our workouts. There was the seven-minute workout. Then the four-minute workout.

But what if you could burn fat and be healthier even faster? Enter the 20-second workout.

It may not be the most dignified workout. But Dr. Michael Mosley, a doctor turned bestselling author, says that just 20 seconds of grunting, groaning and pushing your way through the pain, even in business attire will make you not only skinnier but healthier. We're talking about high-intensity interval training.

Dr. Mosley calls it fast exercise. And it's the title of his new book.

But can one minute total three times a week really lead to remarkable medical changes? The good doctor suggests it's an aerobic fountain of youth, a shortcut to getting maximum benefits with minimum work. What's the key to high intensity?

“This regime, doing short bursts of intense activity, seems to be much more effective not only for losing weight but also for improving your insulin sensitivity,” he said.

Mosley's controversial take points to a growing body of science which suggests it's the stress and intensity of exercise, not the duration, that's beneficial. We're talking weight loss, reduced cancer risk and something that hits close to home for the doctor, diabetes.

“Two years ago I discovered I was diabetic,” he said. “I was a bit overweight. That got me into a fast diet but also got me into a fast exercise regime.”

He continued: “And now I'm 20 pounds lighter and my blood sugars are completely normal. I've gone from diabetic to normal.”

As a guinea pig for his own research, he stays healthy now. But not with a fancy gym. It's a 20-second workout, one you can do right in your own stairwell, in a suit, whether you're fit or fat.

The fast workout is just the latest trend from Dr. Mosley.

His BBC documentary which aired on PBS, “Eat Fast and Live Longer,” launched an international bestseller about the benefits of a two-day a week fast diet. It all began with a wake-up call for the good doctor about where his then 53-year-old body was heading. He'd already lost his father to diabetes.

Researchers across the United States have been finding astonishing results from severe calorie restriction. Decreased cancer risk, increased life expectancy, even improved brain function. So Mosley came up with a diet where you fast on two random days of the week, say, Monday and Thursday, and eat whatever you want the remaining five. But he’s not telling people to starve themselves.

“Oh, absolutely not,” Dr. Mosley explained. “In the regime that I'm suggesting, the maximum you ever go without food is 12 hours.”

Mosley believes he can apply the same principles from his diets to his workouts by looking carefully at the science to trick your body into being healthier.

High intensity interval training, or HIIT, is nothing new in the exercise world. There’s the wildly popular cross-fit phase. But there are critics who say just a few minutes a week really won't cut it. Exercise should be varied and gradual. So high-intensity training should be a supplement to that.