In the process of training, the human body loses a lot of fluid with sweat. As a consequence, a feeling of thirst arises. But many doctors and trainers advise against drinking a lot of fluids immediately after exercising.
Instructors and trainers often forbid their wards to drink liquids immediately after training, since water is quickly absorbed into the blood, thereby increasing its volume, and, as a result, complicating the work of an already loaded heart. Another reason for the rejection of water and any other fluids after physical exertion is the fact that during physical activity, the emphasis of the general activity of the whole body is transferred to the muscles. The kidneys and the digestive system (stomach) are in "sleep mode". Drinking a glass of water will force them to work harder, which will affect overall well-being and slow down recovery after exercise. If a person actively plays sports and drinks water, the kidneys begin to function at the limit of their capacity, and water retention occurs in the body. This helps to lower sodium levels, which are essential for the normal functioning of internal organs. There are cases when marathon runners who drank 2-3 liters of water immediately after the race were hospitalized with acute renal failure. In no case should they drink cold or ice water during training, as well as after several hours after them. Remember the anatomy of the internal organs: the stomach is located directly under the heart. Cold water entering it promotes reflex vasoconstriction, disrupting coronary circulation and slowing down the flow of nutrients into the heart muscle. This can lead to serious diseases of the cardiovascular system. It is also very likely to get sore throat, because under the condition of lowered immunity, drinking cold water in a heated state after training can lead to inflammation of the upper respiratory tract, and sometimes lower (pneumonia).
