Not only it is important to be hydrated while doing all kinds of physical exercise, you also need to be hydrated before and after as it is the best way to recover.
While exercising, hydration requirements depend on:
Level of activity carried out:
Some activities imply energy expenditure 7 times greater than the individual’s basal metabolic rate and others, 3 times the basal metabolic rate. The greater the multiple, the greater the calorie loss.
Heat loss through conduction or convection is better than through evaporation. It will depend to a large extent on the ambience, as, clearly, doing sports in winter is not the same as doing them in summer.
Ambient hydrometric level:
When there is humidity, it is more difficult to transfer heat to the air, e.g. in a sauna when you throw water on the stones. (even though you sweat, if there is humidity outside, your temperature does not drop)
It is not the same if you do physical activity at different humidity levels. The higher you go above sea level and the greater the temperature, the greater the evaporation and dehydration. This gives rise to imbalance in the body.
Evaporation loss of a minimally trained individual is always greater than the body’s capacity to regenerate it, even when there is adequate repletion.
- If there is a loss of 2%, the individual loses part of their capacity to distribute blood and to lose heat in an efficient way. It affects thermoregulation.
- If there is a loss of 3%, there is a long-term drop in performance. Resistance is also lowered.
- If there is a loss of 4% to 6%, there are complications in the locomotor system and contractile function. Muscles are affected, there is a loss of strength and you have muscle cramps and contractures.
- Between 6 – 7 %, more or less severe muscle contractures and exhaustion occur as well as heat stroke possibly leading to coma and death.
A drop of 1-2% in body weight through dehydration implies a drop of 20 % in physical performance.
- High-performance sports activities (triathlon, marathon, long distance running)
- Activities in extreme situations over several days (ultra-trail, ultra-long distance running events, the Ironman, etc.)
- In sports with weights, boxing, where it is necessary to lose weight in order to classify for a weight class.
In order to combat this dehydration, you should take this advice on the intake of fluids into account:
- If the individual does not drink, they tire sooner.
- If they drink depending on their perception of thirst, they will feel less tired.
- If they drink before and during physical activity, the level and capacity of physical work will hold up for a longer period of time..
There is no doubt that the best drink to take during a sports activity is WATER, and you are recommended to take it in small quantities without waiting to feel thirsty. In short, a smaller amount more often is better than drinking a lot at one go.
You need a minimum of 7 to 8hr to completely recover your body’s hydration.
Adverse effects for dehydration:
Queries about the most suitable type of drink for physical exercise are common, as are those about the importance of taking isotonic beverages.
It is important to know that these types of drinks have electrolytes (They are not necessary and hypotonic drinks, like water, are better).
Carbohydrates are consumed while you exercise. Isotonic beverages provide them but in quantities which are 2 to 3 times greater than is necessary. You need a quantity of approximately 20 gr/l. of carbohydrates. Therefore, during exercise, this type of drink needs to be replaced by water.
Thirst is not a good indicator of the body’s state of dehydration, which is why, once it is quenched, you need to drink between 300 – 400 ml more, especially when there has been a major loss.