I did a calculation on exercise similar to one done by Dr M D Eades in "The 6 week curure for the middle age middle".

I went to the calorie calculator at
http://walking.about.com/library/cal/uccalc1.htm
and I input my body weight 190 lbs and a slow hiking rate of 2 - 2.5 miles per hour and a 1000 mile distance.

I got 107955 Calories burned, which when divided by 3,500 cal/pound give 30.84 lbs of weight loss.

So, there is some theoretical possibility of the lack of exercise causing weight loss.

On the other hand, Gina Kolata didn't get along well with Gary Taubes, and was one of those who editorially rejected the book Good Calories Bad Calories.

Now one of his claims on weight loss is one that she appears to support.

I really dislike this second rate "science" of diet and health.