Over the past month or so, the web has blessed us with a handful of articles on the limited effect that exercise—especially running—can have on weight loss.
Some of the arguments are simplistic (albeit accurate enough): people who work out a lot tend to eat a lot afterwards and can easily take in more calories than they’ve burned. People tend to overestimate the caloric impact of their workouts, and underestimate the calories in the treats they think they’ve earned because they’ve exercised. That’s how you get stories about people who gain weight while training for and then running marathons. (Perhaps you’ve heard of the “nine-mile pecan pie,” so named because that’s how far you’d need to run to compensate for the calories a single piece would bequeath to you.)
There’s more science behind the exercise-weight relationship, and a recent article by The Independent’s Sophie Morris (one of those weight-gaining marathoners) does a nice job of laying it out.
For example, Morris writes:
Exercise has been found both to curb and stimulate hunger. Unfortunately, only very intense exercise will suppress appetite. A Loughborough University study found that vigorous exercise increases levels of peptide YY, an appetite-suppressing hormone, and reduces ghrelin, an appetite-stimulating hormone. But an hour later, the appetite will kick in again. Another study, from the University of Massachusetts, found that not only does exercise increase hunger, by increasing levels of insulin and leptin, both appetite-stimulating hormones, but that women are affected more than men.
Another problem with running, unlike resistance work, is that it doesn’t do much to build strength and muscle tone. Says one of Morris’ interviewees: “When you’re purely running, you’re not creating lovely lean muscle fat, so people end up having that ‘skinny fat’ look, where there is no real muscle tone because they haven’t done any resistance work.” The stress of exercise can also increase levels of cortisol, which adds fat to your midsection.
So, if weight loss is the goal, the question becomes this: is it easier to drop a few pounds when you’re not working out? And if it is, the next question is: wouldn’t you rather stay like you are or even gain a few pounds and have the stamina of a marathoner? And maybe the ultimate question is: why do you have to pick? Do a little distance running, throw in a few sprints, add a bit of resistance work, and eat sensibly (i.e., no pecan pie, ever). Balance, people. Balance.
Photo of Homer Simpson in Cerne Abbans by Tim Bunce via Wikimedia Commons
