It is essential to consume fluids in order for our bodies to function appropriately, however evidence suggest that during exercise individuals can experience a state of dehydration which can have a negative impact on exercise performance. It is therefore necessary to restore the fluid balance along with muscle glycogen after exercise in order to avoid any negative impact on sporting performance that is to follow.
There is research available which shows that drinking during exercise can improve performance. In any exercise task that lasts longer than 30–40 minutes, carbohydrate depletion, elevation of body temperature and reductions in the circulating fluid volume may be important factors in causing fatigue. All of these can be manipulated by the ingestion of fluids, but the most effective drink composition and the optimum amount of fluid will depend on individual circumstances. Water is not the optimum fluid for ingestion during endurance exercise, and there is compelling evidence that drinks containing added substrate and electrolytes are more effective in improving performance. Therefore, drinking pure water is better than drinking nothing, but consuming specifically formulated carbohydrate-electrolyte sports drink can allow for even better exercise performance.
It is important to consume enough sodium and fluid to counter the deficit of the sweat volume lost in order to maintain hydration at a fast pace. The current generation of commercially available sports drinks are formulated to meet the needs of many athletes in many different situations. Dehydration impairs performance in most events, and athletes should be well hydrated before exercise. Sufficient fluid should be consumed during exercise to limit dehydration to less than about 2% of body mass. Also, sodium should be included when sweat losses are high, especially if exercise lasts more than about 2 hours. Athletes should not drink so much that they gain weight during exercise, however during recovery from exercise, rehydration should include replacement of both water and salts lost in sweat.
Before any exercise it is essential to ensure “euhydration” or so called normal level of hydration. Therefore after exercise which results in body mass loss caused by sweat loss, water and sodium should be consumed in greater quantity than the loses, as it is important for recovery optimisation and electrolyte balance. In addition to the hydration benefits that are caused by drinking during exercise, ingestion of cold drinks has shown to have an impact on body temperature when exercising in moderate or warm environments and improves exercise capacity in hot conditions.
Finally, the choice of drink to be consumed will depend on the individual and their specific circumstances. Replacement of substrate (muscle and liver glycogen) in addition to water and electrolyte losses is important to consider for post‐exercise phase and prepare the performer for upcoming exercises. On the other hand, in terms of sustaining life, substrate depletion is unlikely to have a negative effect in healthy individuals, but water depletion, if not replaced, can have adverse effects. The current generation of commercially available sports drinks are a good compromised formulation to meet the needs of many athletes in many different situations.
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