Ok, let's wait for the exercise fanatics to get ahold of this thread. I suspect they will attack it just the way the medical establishment has attacked the Atkins diet. People will not be able to accept that building muscle mass doesn't have a profound effect on (every)one's metabolism.

I think one of Kolata's most interesting points is that there's a bell curve in terms of how much individuals can benefit from exercise. The people who befefit the most (and the quickest) become hooked and then are convinced that there is no other way to lose weight and maintain the loss. I have wondered why Dr. Atkins himself became so convinced that exercise was necessary (as opposed to desirable). Anyone know?

I think that hundreds of years from now people will look back on our gyms and fitness centers the way we now look at the thermal baths of the 19th century or other health spas of the past: their social function will be more important than their actual contribution to health.

Having said that I certainly believe (and have seen the evidence) that for many people vigorous exercise and weight training can transform their bodies. But the committment required is outside the realm of possibility for most.