RNR Girl could be correct on this issue. Two guys run marathons at my office. One has as fine a body as a male can have. The other, me, is a toothpick. The hunk says he has an ideal marathon weight, below which his times go up because, as RNR Girl seconds, his energy levels go down. As a toothpick, I find any personal weight gain is fat, and counterproductive for me.