“I have a friend who ran a marathon without any prior training and a less than adequate diet. After the race he was so exhausted he did not hydrate much, nor did he stretch. Instead he fell asleep for a few hours and when he woke up and went to use the restroom he realized there was blood in his urine. What could be the reason for this? Thank you for your time!” (New York City, Ms. LazKey)

Hello Ms. LazKey,

More often than none, excessive, strenuous activity, including running a marathon, may cause skeletal muscle damage, a condition referred to as exertional rhabdomyolysis. More specifically, rhabdomyolysis results from skeletal muscle injury causing leakage of massive quantities of substances into the blood, some of which are toxic. One such substance is myoglobin, a protein released into the blood after skeletal muscle tissue breakdown. Myoglobin should be bound to haptoglobin; however, during rhabdomyolysis, free floating myoglobin can damage kidney tissue. Damaged kidney tissue generally results in acute renal (kidney) failure, and when the kidney tissue becomes damaged, a person’s urine appears as a dark, red color. Similar to your friend, a patient will not only present with dark colored urine, the urine will be scant in volume, and the patient will likely have muscle aches and weakness. Treating a patient with aggressive fluid replacement may be necessary for survival but often is essential to reduce further kidney damage.

Your friend is fortunate not to have developed heat exhaustion or heat stroke during the marathon; however, in the short term, acute renal failure is likely to have occurred. Thus, as a precaution, your friend should ask his doctor to run the tests necessary to evaluate kidney function. The kidneys are essential to remove toxic substances from the blood and reabsorb nutrients and ions necessary for other organs functioning ability.

Rest assured, running the race, without training, was a serious risk, with potential life altering consequences. Nonetheless, he is alive, and I congratulate him on completing the marathon. Thank you on your inquiry and trust, and please stay in touch, as I wish to know your friend’s kidney function test results, post marathon. God Bless you, God Bless your friend, and God Bless New York City.

Respectfully,

Dr. Roshin