Because after exercise, lactic acid will be produced in muscles, and if you don't exercise, lactic acid will accumulate.
After lactic acid accumulates, you will feel muscle pain.
Therefore, massage should be done after strenuous exercise to accelerate blood circulation, take away lactic acid from muscles and reuse it.
Or put your legs higher, above your head or even at the same height as your head.
Soak in hot water after returning home to promote blood circulation.
Finally, it is suggested that it is good for the landlord to love sports, but pay attention to his endurance. It is not good for muscle strain caused by overload.