Exercise Doesn’t Help Weight Loss–What?

by Claudius J West

good calories bad calories book gary taubesI am alternately reading my way through two Gary Taubes’ books: Good Calories, Bad Calories, and Why We Get Fat And What To Do About It.

As Pulitzer Prize winner Richard Rhodes says in his blurb on the back of Good Calories, Bad Calories, “ [This book] is easily the most important book on diet and health to be published in the past one hundred years. . . If Taubes were a scientist rather than a gifted science journalist, he would deserve and receive the Nobel Prize in Medicine.”

Why We Get Fat And What To Do About It is Taubes’ Reader’s Digest version of Good Calories, Bad Calories, providing fresh evidence, building on his previous book’s work, and making the thorough presentation in GCBC a faster read for the casual reader.

This morning, in the chapter titled “The Elusive Benefits Of Exercise” I came across the radical idea that exercise may not, in fact, be useful for achieving weight loss.

But. . . but, that just doesn’t make sense. That’s like saying the world is flat and the sun revolves around it.

Burn all of the calories we take in to maintain current weight. Burn more calories than we take in to lose weight. Burn more by exercising more. We all know the drill.

Here’s the shocker: according to Taubes, the evidence that exercising leads to appreciable weight loss is thin on the ground, you might even say it’s nonexistent.

How can that be? Because when we exercise more, our appetites increase, and we eat more.

Taubes’ begins his chapter by asking us to imagine that we are invited to a celebratory dinner where the chef’s gastronomic talents are par excellence. This is an event you will want to attend hungry, so bring your appetite.

How do you give yourself a big appetite? Skip a meal; forgo snacks; take a walk; workout at the gym.

“Now let’s think about this for a moment. The instructions that we’re constantly being given to lose weight—eat less (decrease the calories we take in) and exercise more (increase the calories we expend)—are the very same things we’ll do if our purpose is to make ourselves hungry, to build up an appetite, to eat more.” p. 40

Why-We-Get-Fat-TaubesMore exercise means more hunger.

This isn’t to say that if you exercise but resist eating more than your usual amount that you won’t go into a calorie deficit. There’s still hope of things working out.

But if you had the capacity to resist hunger when it was just normal hunger (and not exacerbated by exercise), then you wouldn’t need to exercise to lose weight—you’d simply eat less.

I’m all for exercise. I love it. I want to emphasize a distinction between exercise being good for our health and exercise being good for losing weight. The truly unbelievable thought is that exercise is not good for our health—and that isn’t what’s being claimed, here. All of the evidence I’ve seen over the years says that the right kind and the right amount of exercise is beneficial.

But being good for our health is not the same as being good for weight loss, not directly. Indirectly, exercise can elevate our mental and emotional states, and those improved states can help us in other ways to lose weight.

Keep on exercising, for health reasons, but have a realistic view of how much exercise can help you lose weight. Like Doctor Dolittle’s Push Me Pull You, it’s hard to get ahead in the weight-loss game when more exercise also gives you a bigger appetite.

“We’ve been getting steadily fatter for the past few decades, and this might suggest, as many authorities do—the World Health Organization among them—that we’ve been getting more sedentary. But the evidence suggests the opposite, certainly in the United States, where the obesity epidemic has coincided with what we might call an epidemic of leisure-time activity, of health clubs and innovative means of expending energy (in-line skating, mountain biking, step and elliptical machines, spinning and aerobics, Brazilian martial-arts classes—the list goes on), virtually all of which were either invented or radically redesigned since the obesity epidemic began.” p.42

Consider that in 1989 Danish researchers took sedentary subjects, men and women, and spent a year and a half training them to run marathons (26.2 miles). The eighteen men in the study lost an average of an unimpressive five pounds of body fat. (Notice that the amount lost refers to “body fat,” not total weight, so we shouldn’t think more fat was lost but offset by presumed muscle gain.) For women subjects the results were worse: no change in body composition at all.

I once flunked a gym class in high school because of my failure to run a mile and a quarter, which is a way of saying that I hate to run. Years after the failed gym class, against my every instinct, I tried to take up running—”chi” running on a padded track. I trained every other day for a month and could barely make it around the oval without needing to let up—believe me, my pace was far from a sprint.

My belief was that if ever I achieved a condition sufficient to complete a marathon, or even a half-marathon, or even a quarter-marathon, I would be as light as a gazelle with skintight skin that displayed the muscles of my abdomen gloriously. In short, I would be a paragon of physical fitness.

I’m rather glad I didn’t go through all of that only to lose an average of five pounds. Five less pounds would not have transformed me into an Adonis.

GaryTaubesIn Why We Get Fat, Gary Taubes presents further evidence, studies, and reasoning than I have shared with you here to make the case that exercise, by itself, is a weak tool for those hoping to increase their physical activity and thereby lose weight—you’ll have to read the book to get the full story.

“The history of science suggests another interpretation [regarding the relationship between exercise and weight]: if people have been thinking about this idea for more than a century and trying to test it for decades and they still can’t generate compelling evidence that it’s true, it’s probably not. We can’t say it’s not with absolute certainty, because science doesn’t  work that way. But we can say that there’s now an exceedingly good chance that it’s simply wrong, one of the many seemingly reasonable ideas in the history of science that never panned out.” p. 56

It’s a big pill to swallow, this heretical idea that exercise may be a poor weight reducer.

If, when you exercise, you do lose weight, by all means, keep it up. If exercise works for you, mazel tov.

If, on the other hand, you exercise and don’t lose weight, it isn’t that you are doing it wrong—science will back you up on that.

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