Possible causes of hematuria after strenuous exercise: I. Transient hematuria occurs due to a slight contusion of the kidneys from too strenuous activity, usually without pain in the lower back and abdomen, no history of trauma, etc. The hematuria is a transient change and can disappear after drinking more water or resting. It is recommended to routinely check the ultrasound of the urinary system, and if there is no substantial change in the kidneys then there is no need for any treatment, just rest and drink more water; second, there may be lesions of stones in the kidneys, such as kidney stones, bladder stones, etc. When strenuous activities are carried out, the stones rub against the mucous membrane of the urinary system and cause local bleeding, which can then exclude carnal hematuria. At the same time, it may be accompanied by lumbar abdominal pain and small abdominal pain, and it is still recommended to perform urological ultrasound to rule it out; third, malformations of the urinary system, which may appear as transient hematuria during excessive exercise, such as double kidney malformation, horseshoe kidney malformation, ureteral malformation, etc. Such cases are also recommended to perform urological ultrasound for differential diagnosis, and if there is a malformation, surgery to correct the malformation will be performed according to the situation if necessary.