I am really puzzled by the math of the whole calories in, calories out thing, especially since this thread was started months ago. I rode my bike a LOT in August - mostly medium to high intensity rides. 930km, 38+ hours of riding. A conservative estimate of calories burned would be around 25,000 during the month. If 3500 calories equals 1 lb, then that is about 7 lbs worth right? During that month I ate "normally." I probably consumed about 1800-2000 calories a day averaged over time. Although I was not trying to lose weight during August, it boggles my mind that my weight stayed exactly the same the entire month. I did not gain or lose an ounce. If I had not done all the riding, I would have gained 7lb in one month! And clearly I cannot "eat normally" (ie not counting calories) when I am not working out as much as I did when I was on vacation. Now that I'm back at work and can't exercise as often, I will have to go back to counting calories so I don't gain weight. That frustrates me because my hope was that once I reached my goal weight, I could go back to enjoying food in life and maintain my weight thru exercise...