Strenuous exercise can lead to hematuria. Hematuria is the presence of red blood cells in the urine seen with the naked eye or under a microscope, it is a clinical symptom that causes hematuria for many reasons, and simple strenuous exercise can also lead to hematuria, called exercise hematuria. The cause of exercise hematuria is usually because when exercising, there is less tissue fat around the kidneys, and the vibration of the body during prolonged exercise can cause the kidneys to sag, resulting in obstruction of venous return, which causes red blood cell leakage. In addition, blood redistribution during exercise, kidney ischemia and hypoxia, lactic acid content increases, which affects the function of glomerulus and increases permeability, causing red blood cells to exude. During exercise, the kidney can be squeezed and the capillaries are damaged thus causing renal hemorrhage. In addition, running with the bladder emptying can damage the bladder, thus causing hematuria. Therefore, transient hematuria can occur after exercise, and it is best to go to the hospital for urinary routine as well as urinary ultrasound and other tests to rule out any organic lesions.