After an intense workout, such as running for miles or all-out sprinting, there’s a possibility you may notice blood in your urine. Blood in the urine is medically called hematuria, a painless condition. Anyone who’s had a vigorous exercise session may notice their urine appearing bright red, pink, or cola-colored. While seeing blood is disconcerting, it’s generally not a cause of concern. That’s because most signs of hematuria related to intense exercise will go away in a day or two. However, if blood in your urine lasts longer than two days, is becoming more consistent, or your urine output has reduced, it’s time to see your doctor.
Most causes of hematuria are benign, but it may be a sign of a more serious underlying problem such as cancer or kidney disease.
Why does intense exercise cause hematuria?
Not everyone who works out intensely will necessarily experience hematuria. Long-distance runners or sprinters are more likely to be affected by hematuria, even though anyone participating in vigorously intense exercise can also experience this condition. Studies have found that hematuria is more likely to occur in those who practice weight-bearing intense exercise (long-distance running and sprinters) than non-weight-bearing exercises, such as bicycling or swimming.
While the exact cause of exercise-induced hematuria is unknown, it’s generally believed to be due to the kidney’s filtering process of urine. The intensity of the exercise may allow some red blood cells to escape or leak into the urine, causing a reddish hue that is noticeable. This is called gross hematuria, meaning you can see it with the naked eye. Microscopic hematuria is so tiny it can only be seen under a microscope.
Other possible reasons for those who exercise intensely to develop hematuria might be a lack of sufficient fluids or bladder trauma.
Symptoms of a hematuria
The main symptom will be gross hematuria, in which you can visibly see your urine is a reddish or pink color. Otherwise, the condition is painless. The one exception, however, is if the bladder has filled with blood forming a clot. The clot may block urine flow, causing pain in the lower pelvic region. A person must see their doctor right away if this happens.
Other possible causes of hematuria not related to intense exercise
Hematuria can result from many other possible causes unrelated to intense exercise. These possibilities include:
- Urinary tract infection – A urinary tract infection (UTI) can lead to hematuria due to the infection found in the urinary tract. Cystitis (bladder infection) and pyelonephritis (kidney infection), are common sites and reasons for hematuria in the urinary tract.
- Kidney stones
- Kidney or bladder tumors
- Trauma to the urinary tract – Any trauma to any part of the urinary tract, including the kidneys to the opening of the urethra, can lead to hematuria
Even eating certain foods (beets, berries, or rhubarb) or taking aspirin or blood thinners can cause urine to turn red.
For long-distance runners, sprinters, or those participating in other very intense exercises and experiencing hematuria, don’t panic. Instread, see your doctor if it lasts longer than two days, if your urine output has decreased or if the problem is occurring more frequently. Otherwise, hematuria will usually go away on its own.
Dr. David Samadi is the Director of Men’s Health and Urologic Oncology at St. Francis Hospital in Long Island. He’s a renowned and highly successful board certified Urologic Oncologist Expert and Robotic Surgeon in New York City, regarded as one of the leading prostate surgeons in the U.S., with a vast expertise in prostate cancer treatment and Robotic-Assisted Laparoscopic Prostatectomy. Dr. Samadi is a medical contributor to NewsMax TV and is also the author of The Ultimate MANual, Dr. Samadi’s Guide to Men’s Health and Wellness, available online both on Amazon and Barnes & Noble. Visit Dr. Samadi’s websites at robotic oncology and prostate cancer 911.