This story might apply to you if you are a: - skinny, nondiabetic vegan - life long runner - amateur runner who is cranking up the volume right now - have arthritis in other parts of your body (I got what one doctor called knee arthritis in one knee) - have a mystery chest pain you didn't use to have - you're an increasing old male, about 50 or older If not, then my story might not apply to you, go read real medical advice. So I wake up in the middle of the night with chest pains. I google to see if it is a heart attack-- no feeling of weight on chest, heart rate is slow, no arm pain, etc. I go back to sleep but figure I should get it checked out. Chest continues to hurt during the day. Worse at the end of a hard run, fine in early morning, starts up again as the day goes on. Dr Google suggests that as an old, 49 year old, male life long runner, I might have atrial fibrillation or something else, maybe costochondritis (rib cage arthritis) or heart burn. It probably is not heart...