Brown urine after exercise may be a result of concentrated urine or hematuria after exercise. Among them, hematuria may be caused by myoglobinuria, kidney stone detachment, renal vein compression and other factors. 1. Myoglobinuria caused by rhabdomyolysis: this is due to a large number of exercise leads to rhabdomyolysis release a large amount of myoglobin, myoglobin with the urine discharge, so the urine is soy sauce color. 2. Kidney stones caused by hematuria: after strenuous exercise stones may appear to move and damage the mucous membrane of the urinary system causing hematuria after exercise. This situation is often accompanied by severe back pain, nausea, vomiting and other symptoms. 3. Renal vein compression: Nutcracker syndrome patients with renal vein compression may experience increased compression after exercise resulting in bruising and hypoxia of the kidneys, resulting in hematuria. 4. Concentration of urine: After exercise, a lot of sweat, at the same time, if you drink less water can make the urine concentration, color deepening, and thus may appear brown. Urine becomes brown after exercise, it is recommended to consult a doctor in a timely manner to standardize the diagnosis and treatment, and active treatment.