Skateboarding

I spent the last 2.5hrs skateboarding and my blood sugar is 52. I complained once that I go low when I exercise if I don't eat (guess who didn't eat today?). I think if he weren't as professional as he is my doctor would have said "Well duh!". ;) He did however say that even he'll go low if he doesn't eat when he exercises. And I thought non-diabetics were normal all of the time...