Why Exercise Won\'t Make You Thin
That's the title of the current (August 2009) Time Magazine Cover Story.
It's worth a read, but the subtitle, "The Myth About Exercise" is mistitled.
Rather than the myth of exercise, it really uncovers the hypocrisy we often engage in when involved in a vigorous exercise program. Often, overweight people even exercise more regulary than people of average weight.
The reasons: when we exercise we tend to:
1. Move less during the rest of the day - due to being tired, or sore, or just feeling we don't need to move extra during the day because we worked out so hard
2. Increase our intake of calories - increased appetite, or "rewarding" ourselves for our hard work with snacks. The article mentions that students who started an exercise program, on average ate 100 calories extra, over the amount they burned exercising.
Oh, the lies we tell ourselves.