I typically bike to/from the blood bank ... never had an issue. I'll take it easy on the way home, keeping heart rate under 130. Next day, treat it like a recovery rider, get miles without big efforts. I will not donate 6 week prior to a major race, and I avoid donating over the summer since I have a major event most every month ... additionally, the body produces additional blood volume in the heat to help with cooling, so donating will make it harder for the body to cool off (and I struggle in the heat).
