From a health point of view, you can do it before or after exercise. You can supplement milk to get energy before exercise, and make preparations before exercise consumption to avoid the needs of the body. Supplementing milk after exercise, too much exercise, can replenish the energy needed by the human body in time. So it's good before and after

In life, it is generally recommended to drink milk in the morning and evening, because milk supplementation in the morning can replenish the human body in time. Because of sleep, the human body needs a lot of energy and nutrition to fill it. Supplementing milk at dinner can promote gastrointestinal peristalsis, regulate gastrointestinal tract and be beneficial to health.

Extended data:

If you drink milk before exercise, the protein in milk will decrease during energy consumption. Drink after exercise, absorb well, and promote sleep.

Drink milk after half an hour of exercise. Milk contains a lot of protein, which is easily absorbed by human body after exercise. Very suitable for people who practice muscles. But it must be noted that after at least half an hour of exercise.

You can't take a bath immediately after exercise because your pores expand after exercise. At this time, if you take a bath, your skin will be strongly hurt and stimulated, which may cause a cold. I suggest that you should pay attention to rest while doing physical exercise, so that you can have a good figure by combining work and rest.

References:

After jogging, eat properly and don't get fat. It is more effective to drink milk to restore physical strength after fitness (2) People's Daily Online