If you fail to drink enough during a marathon and your body weight falls by more than 2 percent because of fluid loss, you may become sick because of the stress on your body. Click HERE for More Information. Then I realized what caused it. I just wasn't used to playing tennis for that length of time. Nobody knows exactly what happens during exercise to cause hematuria, but there are several theories.
Many experts believe it results from trauma to the bladder.
Repetitive pounding from running and other strenuous sports can cause mini hemorrhages in the bladder, they speculate. Dr. Miller thinks exercise-induced hematuria comes from old red blood cells that break as they travel through contracting muscles that are working hard. What shows up in the urine is hemoglobin, the oxygen-carrying component of the red blood cells, he says. They found a number of fellows with blood in the urine. They concluded it was the muscular contraction, over a period of time, that caused old red blood cells to break because they were squeezed.