I rode a 600k brevet this weekend. Took a lot of care to eat and drink enough throughout the 30+ hours of riding. At the end of the ride, I was tired (mostly due to lack of sleep), but never felt depleted. Weighed myself at the end of the ride -- down five pounds. Ths may not seem like a lot to some of you but it is 3.5% of my body weight so it's a lot to me. At 9% body fat, I can't lose 5 pounds through normal workouts, nutrition, etc. Since I was not hungry or thirsty at any time during or after the ride, where did the weight loss come from? Will the weight rapidly return as my body recovers over the next few days.