There are no fat sprinters

This post is by Phil.

A little over three years ago I wrote a post about exercise and weight loss in which I described losing a fair amount of weight due to (I believe) an exercise regime, with no effort to change my diet; this contradicted the prediction of studies that had recently been released. The comment thread on that post is quite interesting: a lot of people had had similar experiences — losing weight, or keeping it off, with an exercise program that includes very short periods of exercise at maximal intensity — while other people expressed some skepticism about my claims. Some commenters said that I risked injury; others said it was too early to judge anything because my weight loss might not last.

The people who predicted injury were right: running the curve during a 200m sprint a month or two after that post, I strained my Achilles tendon. Nothing really serious, but it did keep me off the track for a couple of months, and rather than go back to sprinting I switched to cycling, which is much easier on my knees and ankles (which are pretty messed up after years of field sports). At this point it’s fair to call me an avid cyclist, of the mockable sort (lycra, shoes you can’t walk in, etc).

People who suggested my weight would return were wrong, at least so far. I stabilized at around 193-195 and stayed there for about three years. During that time I’ve gotten my heart rate close to my maximum twice a week or more in most weeks, by riding up steep hills as hard as I can. I occasionally wear a heart rate monitor, but at this point I can also gauge my effort well enough to avoid cheating. (This is harder than it seems: it’s tempting to merely go very very hard, rather than literally as hard as I can; the former is uncomfortable, the latter feels awful, but only for a very short time). Of course I’m also getting other exercise on my bike — I ride for hours sometimes — but for reasons described in that previous post I think it’s the high-intensity exercise that has a big effect on my weight.

Several months ago, some friends and I signed up for a bike trip in the Pyrenees in July (in two weeks now). A few legs of the route are pretty intimidating — long, steep climbs at fairly high elevation — so after signing up for the trip I started training more: getting an hour ride in before work, riding farther and harder on weekends, etc.  After a couple of months I was a stronger biker than ever, but my weight was still around 193-195 pounds. That’s not bad for someone over 6 feet 3 inches tall, but it’s about 8 pounds heavier than when I last tried to play competitive sports at a reasonably high level, fifteen years ago, and 14 pounds heavier than a pro cyclist who is more than an inch taller than I am (as you can see in this touching article about Taylor Phinney.

I’ve never been concerned about weight loss per se; I think of it as an unintended (but welcome) consequence of my activities. Weight loss has never been a goal, in other words.  But about a month and a half after I started training for my trip I was chatting with a biking friend who is much faster and fitter than me, and who weighs even less than Taylor Phinney in spite of being almost my height, and he suggested I lose some weight before my Pyrenees ride. I told him that although it would be great to haul 10 fewer pounds of fat over every mountain with me, I wasn’t willing to diet to do it. I enjoy exercising, and even get satisfaction, though not enjoyment, out of maximum-intensity exercise, but I do not enjoy not eating!

But, upon reflection, I did decide to try to do two things to see if I could lose weight before my big ride: (1) reach my max heart rate 3 or 4 days per week instead of 2, and (2) weigh myself every morning. The theory behind (2) is that if (1) was working then this would provide encouragement to continue, plus perhaps my subconscious would control my appetite a bit in response to the weight on the scale. So for the first time in my life I had a weight loss goal!

That was about 10 weeks ago, and I now weigh under 188 pounds, so I lost about 6 pounds in 10 weeks. I think this puts me at around 10% body fat, maybe just slightly higher. I’m about 20 pounds lighter than I was three years ago when I put maximum-intensity intervals back into my routine.  I seem to have stabilized, with no change in the past two weeks, which is too bad since I’d love to have gotten down to my playing weight from 16 years ago. But I’m not going to give up chocolate crepes and other pleasures of life just to ride my bike uphill a little bit faster.

In conclusion:

1. I continue to believe that studies that claim that exercise doesn’t lead to weight loss are wrong. I think this may be true of low- and moderate-intensity exercise,  but I think that if you really go all-out, a few times per week, you will end up with low body fat (at least, low by current U.S. standards).  There are plenty of chubby joggers, even ones who regularly run marathons, but there are no fat sprinters.
2. For me, when it comes to weight it doesn’t seem to matter whether the intense exercise is in the form of running or biking.
3. To try to discourage a theme that cropped up in the previous post, three years ago: I am _not_ claiming that high-intensity exercise is part of the solution of America’s obesity problem, or anything of that sort. There is just no way most people are going to give maximum effort three or four days a week. I will probably slip back to two days a week when I get back from my trip, in fact, in which case I expect my weight to climb back up in to the low 190s.

This post is by Phil

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