May 07, 2009
Time to get up off the couch and -- oh, never mind
As it turns out, hitting the gym may not be necessary -- or even all that helpful -- when it comes time to lose that gut. Seems like the most effective exercise is putting down the fork and pushing back from the table.
Susan Roberts, a professor of Nutrition and Psychiatry at Tufts University, says that exercise is not the key ingredient in an effective weight loss regimen. Roberts, who wrote the book, The Instinct Diet, posted recently at The Daily Beast.
The notion of going to the gym—burning, say, 500 calories a session, six days a week, and thereby eliminating 3,000 calories (or about a pound of body fat) in a single week—is very appealing. Just think: Lose 50 pounds plus get great abs over the course of a single year, all without dieting!
But a hard look at the evidence just doesn’t support the hype. The inconvenient truth is that we now eat about 500 more calories per day than we did 30 years ago. That's enough to explain our growing waistline without any need to factor in exercise.
Combine this fact with national surveys showing that people who do manual occupations—jobs like construction, farming, and domestic work—are heavier than people who sit in front of a computer screen all day. Indeed, these physically strenuous jobs carry a 30% increased risk of obesity when compared to office jobs. Of course, comparisons like this don’t factor in social class, or whether you eat brownies, or take a run after work, but that’s the whole point—compared to factors like what we eat and what our education level is, hard manual labor just doesn’t make as much of a difference. Even if your day is spent shoveling gravel, you’re still going to find yourself with a pot belly if you’re always lunching on pizza and soda.
The evidence isn’t just anecdotal. My lab at Tufts University summarized 36 years of published studies on exercise and weight, conducted between 1969 and 2005. What we found would frustrate anyone spending upward of $800 a year on a gym membership to lose weight. The averaged results of the studies showed that an hour of exercise per day results in an average fat loss of just six pounds over the course of several months—hardly the benefit one would expect from all that work.
Perhaps more importantly, most of the studies only managed to get people to exercise 30 minutes a day, which is the maximum most people have the time and inclination for, at which point the average weight loss goes down to a meager three pounds. It is true that some of the studies showed greater fat losses than the average, but just as many showed less.
[...]
Research doesn’t have good answers to the question of why exercise doesn’t work for the average person as well as it seems it should, but I suspect the reasons are increased hunger (you eat almost as many extra calories as you burn) and reduced energy expenditure at other times (exercise may make you more relaxed and less fidgety). So, you end up fit, healthy, and less stressed out, but wondering why you still have pounds to lose.
On the other hand, 85 percent of people entering a no-exercise weight-loss program at my lab lost 10 to 50 pounds, giving us the clear message that exercise isn’t the key to getting slim. Which doesn’t mean you should tear up your gym membership—being fit remains good for your general health. It is also clear from research studies that one hour of exercise a day is helpful in keeping weight off after you have lost it with a diet program.
[...]
The important thing to know is that you have a choice. Exercise is great medicine for general health and a great add-on to dieting, so feel free to kill yourself in the gym if it makes you feel good. But it isn't essential, and by itself doesn't do much. All the evidence suggests that exercise is less important than what goes in your mouth, and when.
It doesn't really require a PhD to understand that weight gain isn't calculus, or even algebra; it's simple arithmetic. Calories consumed - calories burned = either a positive number, no net change, or a negative number.
I saw the comic Kip Adotta perform a standup routine twenty years ago about the latest weight loss fads. He told the audience, "Let me sum up every diet book ever written." Turning sideways to the crowd, he thrust his butt out and bent over a little bit.
"You can pack it in faster through this hole," he said, pointing at his mouth, "than you can get rid of it through this hole," pointing at his ass.
I don't know why it is we're constantly surprised to find that out.
Posted by Mike Lief at May 7, 2009 07:45 AM
| TrackBack
Comments
I think the caveat to this article, and the author points it out herself, is that there are a tremendous number of health advantages to exercise, particularly cardio. The heart is a muscle that needs to be worked out. Exercise also helps alleviate stress in most people which reduces blood pressure. Also,workouts can actually redistribute weight, making you heavier if all you are looking at is a scale and not measuring your body mass index. Muscle weighs more than fat. So it is not surprising that some people who worked out a lot did not lose as much weight, assuming they converted some fat to muscle.
Weight loss and health although seemingly the same issue really are not. They are distinctly different.
I have recently lost about 30 lbs. Somebody asked me what the secret was and I told them "I eat less". DUH. I still am not convinced though that just because I am lighter means that I am necessarily in better overall shape.
Posted by: RW at May 7, 2009 12:43 PM
Just goes to show you that SpellCheck won't always protect you.
Posted by: The Little Coach at May 7, 2009 12:52 PM
That was some miiigggghhhtttyyyyyy good garlic bread last night!
Posted by: Thin Ice, Sr. at May 8, 2009 05:58 AM