Exercise and weightfat loss

You've probably heard, read or seen that you must exercise to lose weight/fat, or that exercising will drastically improve the amount or rate of weight or fat loss. It's important, once again, to make a distinction between weight and fat loss, as you'll see in a second.

People obviously can and do lose weight all the time without exercise (keeping the weight off is a separate issue I'll come back to) so exercise certainly isn't required. So you might be wondering if exercise has much of an effect on the rate of weight loss. For the most part, exercise has, at best, a small effect. Some studies find that it increases the total weight loss slightly, most find no effect. As I'll mention below, some studies find that exercise actually reduces the total weight loss.

Why? Why doesn't exercise improve the total rate of weight loss. The reason is one of simple mathematics and reality. Under most dieting conditions, unless a tremendous amount of exercise is or can be done (and this usually isn't the case for overweight individuals) such that a very large amount of additional calories are burned, exercise simply fails to have much of an impact.

That is, unless you're capable of literally hours per day of exercise, sufficient to burn a ton of calories, the calorie burn from exercise will generally be quite small compared to the deficit created by food restriction. And the average overweight individual who is sedentary simply won't be able to burn enough calories with exercise to greatly impact on the overall deficit. From a weight loss standpoint, about the only people who are able to burn a ton of calories with exercise (athletes) are the ones who don't need to in the first place.

This is even more the case on a crash diet such as this one where the daily deficit is already pretty monstrous. That is, once you've generated a daily deficit in the realm of 1500-2000 calories/day (or higher in some cases), burning a few hundred more calories per day with exercise simply doesn't amount to much. Which isn't to say that exercise is useless but it's unrealistic to expect the addition of most exercise regimes to drastically increase the rate of weight loss.

Quite in fact, some studies suggest that there will be less weight loss if exercise is included during the diet but this is sort of misleading. The reason is that, in beginning exercisers, exercise can cause an increase in LBM/muscle mass and this affects the amount of total weight that is lost. Less weight will be lost but only because LBM is being gained (or less LBM is being lost). I suspect that this is why some rapid weight loss centers actively recommend against exercise: they want to generate the greatest scale weight drops and that means avoiding anything that spares of increases LBM.

Of course, this is totally misleading, as I mentioned above. Maintaining (or even increasing) LBM on a diet, at the expense of fat loss shouldn't generally be construed as a bad thing. It's simply one of those places where focusing only on weight loss leads folks to bad conclusions and even worse recommendations.

I should mention that, in gaining weight, some proportion of that weight is LBM (some of which is muscle and some of which is simply connective tissue to support the extra weight) and most obesity experts accept some LBM loss as part of the weight loss. A LBM loss of 25-30% is usually considered acceptable in obese individuals since that represents the 'extra' LBM they gained getting fat in the first place. But I digress.

Natural Weight Loss

Natural Weight Loss

I already know two things about you. You are an intelligent person who has a weighty problem. I know that you are intelligent because you are seeking help to solve your problem and that is always the second step to solving a problem. The first one is acknowledging that there is, in fact, a problem that needs to be solved.

Get My Free Ebook


Post a comment