Want to Lose Weight? Try Short Sprints

We all probably have different reasons for riding bikes. It keeps us fit, it’s fun, it’s good for the environment, yadda yadda — but I’m sure we’ve all heard stories of people who ride and throw off all kinds of weight as a result.

I gotta be honest — that hasn’t happened to me (although I’m sure it’s not biking’s fault). But then, I happened upon a report of a study done in Australia that tried to find the least amount of exercise you can do for the biggest impact. Forget long slow distance. It’s sprinting.

sweatyThe researchers studied 40 overweight men for 12 weeks — and put them on spin bikes. The men exercised three times a week, but their routines were strenuous — they’d sprint for eight seconds, then pedal easy for 12 seconds, then repeat — for 20 minutes. Now, I’ve done intervals from time to time in the past, but I’d go hard for at least 30 seconds before slowing down. It’s hard to believe that a repeat as short as eight seconds would have any effect.

It did. In the study, the participants lost an average of two kilograms of fat — about four and half pounds — and gained 1.1 kg in muscle mass. Spread over a week, you’re only working hard for eight minutes if you try this regimen.

What’s cool is that the fat loss came where it’s most critical — in the fat that surrounds internal organs and is linked to a higher risk of cardiovascular disease. A control group that did no exercise lost no weight. Both groups were told to stick with their regular diets.

Although this study involved only men, previous studies have reportedly shown similar results in women.

On the bike yesterday afternoon, I thought I’d give the short sprints a try. I didn’t put a clock to it, but I did count off “One Mississippi, two Mississippi,” up to eight as I pedaled hard, then counted the same way to twelve while pedaling easy. It was weird. By the time I got up to full speed, it was time to back off. The twelve count goes by fast too, and I had to get up on the pedals again. In order to reach the speed I was targeting, I stood on the pedals for four seconds, then sat for the remaining four.

Eight seconds of effort doesn’t tire you out. But cumulatively, you feel it. I did the exercise over a mile-and-a-half stretch of straight road, then stopped when I came to a red light. That didn’t get me the 20 minutes of exercise the study participants did, but it did give me a feel for the effort. I have a hunch that 20 minutes would really make itself felt.

The short, fast sprinting is supposed to work on two levels: it releases a group of hormones that cause muscles to burn fat, and it keeps lactic acid release to a minimum.

Once I’m fully recovered from the effects of my fall (riding is really helping speed up that process, by the way), I intend to try the 8/12 repeats on a more structured basis. It’s a kind of riding I’ve never really done, but the novelty of the approach might make it interesting. I hope so. After my short sprint tryout yesterday, my weight today was one pound more.