1, urine contains urea, inorganic salts and other components, making urine yellow;

2. After exercise, some water in the body is excreted in the form of sweat, and the proportion of urea in urine is soaring, resulting in yellow color;

3. During exercise, organic matter in the body decomposes to produce lactic acid, urea, etc. , so that the urea content in the body is high, and urine is excreted through urine, resulting in yellow urine.