Hydrating, like eating a balanced diet, is extremely important in fitness and in sports in general. If the body does not get enough calories during physical effort, it can take them from its own ‘deposits’ of adipose tissue, or even from the muscular proteins; but when water is insufficient, things are much more complicated and there are bigger risks for the body.
Water is involved in all the metabolic processes, so not providing the body with enough liquid can have as a consequence perturbation of the bio-chemical reactions, which directly influences the effectiveness of the training and even the practitioner’s state of health.
Physical effort, especially the aerobic ones, leads to dehydration through perspiration (which regulates the temperature of the body, preventing over-heating). There is a very strict rule which imposes drinking water (liquid) before, during and after physical effort. Besides regulating the body temperature, correct hydration helps in eliminating the toxic substances that result during and after the training (urea, sodium, etc.) much more easily; hydration acts like a ‘means of transport’ through perspiration and urine. Thus, the metabolism of blood sugar, lipids and proteins is developed under good conditions, ensuring contraction force for the short term and especially for resistance efforts.
There is also the opposite of dehydration – over hydration, caused by excessively consuming water. In this situation, besides the inconvenience of frequent urination, the blood vessels are overloaded and this leads to making the heart work harder as it must increase the intensity of pumping due to the increased volume. As a consequence, the effectiveness of your training is hindered and your athletic performance does not get to the expected level. The sensation of having a ‘heavy body’ can also be an unpleasant symptom of over hydration.
As for the type of liquids, the sportsman must supervise the level of effort which produces dehydration and melting of the glycogen reserves. Besides water, the practitioner can use isotonic drinks, (which have an electrolytic composition similar to the one of the body) or liquids containing sugar which are easily and quickly absorbed by the body (fructose, glucose, dextrose, etc.). All of these can contribute to fast restoration of the glycogen reserves of the body. It is advisable to drink the liquids in small and frequent doses, so that the body assimilates them better and they do not briskly overload the body during physical effort.
Both in over hydrating and in dehydrating, there is the risk of putting the renal excretory function to work too much . Over hydrating can have significant elimination of electrolytes as a consequence, which are precious for the body (potassium, sodium, iron, zinc, etc), and need to be replaced from sources as naturally as possible (fruit, vegetables, mineral water, etc.). In case of dehydrating, the volume of urine will be severely diminished because the body will try to retain mineral salts and vitamins. Besides unwanted deposits, renal lithiasis, gout, etc., a very severe consequence of this effort of the body to retain liquid is renal blocking.
Correct hydrating involves a certain discipline, which means that liquids must be consumed repeatedly during the day, not only during physical effort. A person should not get to the feeling of thirst. This is a very late alarm, signaling that the right quantity of water has been missing from the body for a couple of hours. Except while eating and immediately after, in order not to perturb digestion by excessive diluting, a real prophylaxis of dehydrating and over hydrating can be made through correct, constant and preventive consumption of liquids.