You can't. After strenuous exercise, if you drink too much water at one time because of thirst, it will reduce the salt content in the blood, sweat more in hot days, lose salt more easily, reduce the osmotic pressure of cells, and lead to imbalance of sodium metabolism and muscle spasm. Due to the insufficient blood supply to the gastrointestinal tract during strenuous exercise, the function is not good, and the absorption capacity of water is weak, and too much water penetrates into cells and intercellular space. Brain tissue is fixed in a hard skull. The swelling of brain cells will cause the increase of brain pressure, which will lead to the symptoms of "water poisoning" such as headache, vomiting, lethargy, blurred vision and slow heart rhythm. Drinking too much water at a time will make the gastrointestinal tract uncomfortable. If you lie down and rest, it will squeeze the diaphragm and affect the cardiopulmonary activity. Therefore, don't drink too much water when you are thirsty after strenuous activity. You should drink water by "drinking less many times".

Extended data:

Some suggestions after exercise:

Can't rest right away. During strenuous exercise, people's heart beats faster, muscles and capillaries dilate, and blood flows faster. At the same time, the rhythmic contraction of muscles will squeeze the venules, prompting blood to flow back to the heart quickly. At this time, if you stop to rest immediately, the rhythmic contraction of muscles will also stop. A large amount of blood that originally flowed into the muscle can't flow back to the heart through muscle contraction, resulting in a drop in blood pressure and temporary ischemia of the brain, which may lead to palpitation, shortness of breath, dizziness, pallor and even shock and fainting. Therefore, after strenuous exercise, we should continue to do some small movements, and then stop to rest after breathing and heartbeat are basically normal.

You shouldn't drink too much. When thirsty after exercise, some people binge drink boiled water or other drinks, which will increase the gastrointestinal burden and dilute gastric juice, which will not only reduce the bactericidal effect of gastric juice, but also hinder the digestion of food. Drinking water too fast will also increase the solubility of blood too fast, which will suddenly increase the burden on the heart, cause electrolyte disorders such as potassium and sodium in the body, and even lead to heart failure, heart tightness and abdominal distension. So don't drink too much water too fast after exercise, and don't drink cold drinks, otherwise it will affect your body temperature.

References:

Baidu Encyclopedia-Suggestions after strenuous exercise