I follow Dr. Mike Eades on Twitter and he alerted his fans (that would be me) to a great study on exercise and weight loss that was published last year. (I read the study, and it is OK except I am not all that thrilled with the way they threw out some data points, but I'll save that rant for another post someday.) Like Dr. Eades hinted, the conclusion is a bit odd.
Here's the study in a nutshell:
1. We found a bunch of studies about exercising and weight loss and they didn't show much of a relationship, so we designed a newer, bigger, better, longer study.
2. We found and measured a bunch of fat, lazy, old women.
3. We told them to exercise but not to go on a diet.
4. After a year of exercising at an average of 9256 minutes, they lost an average of 4.4 pounds.
5. We conclude that exercise helps you lose weight
Now I don't know about you, but that doesn't sound like alot of weight lost for all those hours put in. That works out to about 1/2 oz. of weight lost per hour of exercise. I think that I would get better results by skipping the weekly exercise and just shave and trim my nails before the weekly weigh-in.
Dr. Briffa has a great article about this clinical study, with a bunch of links to other studies that showed little to no weight loss associated with exercise.
You might find in some places where folks have analyzed the weight you should expect to lose while exercising. You know, where you would have to be on the treadmill for another X minutes to burn off that Y amount of strawberry jam on that bagel. If you assume that you can burn off 100 calories in 10 minutes of intense exercise, that would give you weight loss change of about 100 times better than this new study actually shows. So, it's even much worse than we thought for weight loss.
Here's the original study: