A customer came into the store today with a problem and has tried just about everything. He has been running long distance and started to have blood in his urine, the amounts ranging from a little blood to a large amount of blood. He is constantly hydrated, drinking water all the time. He went to a urinary specialist and had surgery where a benign mass removed from his urinary tract, there where no signs of cancer. His doctor said he would not have the problem anymore but when he started running again it came back so his doctor told him to stop running. He rides bikes and runs occasionally on the treadmill for amount 30 mins. (he gets a very small amount of blood in his urine sometimes after the treadmill). Does anyone have any idea why this would keep happening? And remember he is not dehydrated.