When I was in the Air Force, I was exercising daily, playing full-court basketball, riding my bike, walking everywhere, but still gained weight. When I got close enough to be put on the fat boy program, I was put on this stupid regimen. Was working my ass off without working my ass off. Total weight lost over 3 months was six pounds. In the late 90s, I found the Zone, which worked very well for me, and I was able to lose 20 pounds in about a month, without even exercising.
The change in diet and body composition was studied in a group of 9 female and 18 male subjects, starting a training program for 18 months with the ultimate goal of running the marathon.
[...]
In males the body fat mass decreased 2.4 kg, while in females no change in body composition was observed over the 18-month training period.
Yep. Eighteen months of training, and the men lost five pounds and the women lost zilch.
They did, though, all complete the marathon.