Does Exercise Really Work?

It's a ritual of health journalism. Every few months, journalists plumb the science of exercise to give readers The Definitive Guide to good health. It happened again this past weekend in The New York Times Magazine.

"How exercise affects body weight is one of the more intriguing and vexing issues in physiology," wrote The Times' Gretchen Reynolds, stating a fact that might explain why the topic is revisited so often by journalists. Gawker was quick to point out that this was far from the first time the paper of record addressed the subject. Just a few weeks ago, Anahad O'Connor looked into whether lifting weights can help one slim down and, in November, Reynolds herself wrote a lengthy blog post on why exercise doesn't lead to weight loss.

Of course, The Times is not the only New York publication on the case. Three years ago New York Magazine asked "does exercise really make us thinner?" (The Times question ran, "Does working out really help you lose weight?") Both pieces ended not with answers, but with other things to be concerned about while exercising. New York magazine concluded that we just need to watch what we eat:

The benefits of exercise include the joys of virtuousness. I worked out today, therefore I can eat fattening foods to my heart’s content. But maybe the causality is reversed here too. Maybe it’s because we eat foods that fatten us that the workout becomes a necessity, the best we can do in the battle against our own fat tissue.

And The Times emphasized that what may matter most is how much we sit:

Standing, for both men and women, burned multiple calories but did not ignite hunger. One thing is going to become clear in the coming years, Braun says: if you want to lose weight, you don’t necessarily have to go for a long run. “Just get rid of your chair.”