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.

Pre-Thanksgiving Intervals

I got home early today. The university is closed Wednesday so students can travel home for Thanksgiving, but students being students, many of them lighted out today. Heck, I’m aware of a few who took off after classes last Thursday. Anyway, with only five students showing up for my afternoon lab, and finishing their tasks within an hour, I got an early start on vacation, too.

I decided to take advantage of unseasonably warm weather to get in a bike ride. We’re traveling for the Thanksgiving holiday as well, so this will be my last chance to ride until Sunday. Before setting out, I took a few minutes to dig my headlight out of the bike stuff box and mount it on the bike. I don’t ride in the dark as a rule, but the long shadows of late afternoon make a front light as useful as a tail light.

My ride would only be about an hour, just a few laps at the Veloway. I often get over there on late Tuesday afternoons, and try to get in a little speed work. It’s the only time during the week that I really try to ride fast. Today, it occurred to me that I should try the intervals my friend Joe was doing when I ran into him a couple of weeks ago.

His intervals aren’t rigidly structured. Two minutes all out, two minutes easy. I did a warmup lap, then noted the time on my bike computer, stood on the pedals, and pushed hard.

After about a minute, I was ready for this interval to end. Not only was I going reasonably hard, but in this section of the Veloway, the track is a slight upgrade. I kept pedaling against the resistance, and finally saw two minutes click by.

Not being an experienced intervalist, I suspect I really mucked up the easy part of the ride by not riding easy enough. I caught myself powering through a curve, and reined it in. After another minute ticked off — in what seemed like a much shorter period of time — I stomped on it again.

The intervals were good. I felt powerful throughout the ride, although I’m sure I didn’t do the fast parts nearly as fast as Joe does. I know I didn’t keep up the effort as long as he does, either. Three laps on the Veloway, plus riding from and to my house, comes out to about 15 miles. I do it in less than an hour.

It was dusky enough that I could see the beam of my headlight hit the pavement ahead of me on the way home. While I’ve often stated on these pages that I’m not much for training, I also know that to get faster, you have to ride faster. I have no aspirations of joining the A ride in my club, but I’d like to be able to open it up halfway through a Sunday ride and still have some stuff in reserve for the trip home. Maybe doing this unstructured structured riding once a week will help me toward that end.

I’m also feeling a bit smug about the ride, because it left me feeling as though I can save a little space for all the food I’ll be eating over the next three or four days. My wife and I are traveling north to see our new grandchild, all of 10 weeks old — and no, I’m not taking my bike along with me, even through Minnesota is also enjoying some relatively mild weather for this time of year. Sometimes, you just have to deal with things that are more important than biking. See you Sunday!