Every morning I get up really early and bike 10 km on the stationary bike. I work out, I have a huge yard to maintain, and so I'm in really good physical condition..yet, I go out for an intense mtb ride and when I come home I feel really sick and nearly throw up. (Sorry for being gross..) I gotta be doing something wrong right? It's not like I'm too fat or too weak or anything. Does this happen to you guys? For those of you who go for like 5am rides, what do you eat before you go?