Water, mineral water, beer and sports drinks to compensate for fluid loss during physical exertion
A. Jäger, K. Krennhuber - Water, mineral water, beer and sports drinks to compensate for fluid loss during physical exertion - Proceedings of the 11th International Conference on Biosystems Engineering 2020, Tartu, Estland, 2020, pp. 148-157
The human body consists predominantly (over 50%) of water. A clear indication of how important a balanced fluid management is for us. It is noticeable, that many people still do not consume enough liquid, perhaps unaware of the daily ration required, and some simply do not think about regular drinking. With the foreseeable increasing exposure to warmer temperatures (keyword global warming) or simply during physical exertion, especially sporting exertion, a sufficient supply of suitable fluids is necessary, to compensate for the loss of water and trace elements. Serious health risks can occur if appropriate countermeasures are not initiated fast enough. The body loses water and minerals - mainly sodium - through perspiration, which must therefore be compensated by the intake of fluids. Sweat losses can reach up to 2- 3 L*h-1 at a sodium content of 50.8±16.5 (mmol/l) [mean ± SD]. The consequences of the fluid imbalance are the reduction of the plasma volume, the reduction of the blood circulation, the promotion of hyperthermia. Any loss of fluid affects the physical and cognitive function of the body. A well adjusted fluid balance leads to an increase in performance, protects the body from overheating (thermal stress), minimizes the risk of injury and helps delay the onset of fatigue.
The authors have examined water, "mineral water", sports drinks and (alcohol-free) beer to determine its suitability for compensating loss of fluid and electrolytes. The mineral water rarely shows an increased content of mineral salts and only a low osmolality: The electrolyte content is often similar to drinking water in the water extraction region. Alcohol-free beer is currently strongly recommended in advertising as a liquid substitute for physical performance and is actually predominantly isotonic. A problem of all these drinks is the low sodium content because especially sodium that is lost with the sweat in large quantities should be replaced when drinking, as it is necessary for the whole cell physiology and signal transduction processes. Only sport drinks supply (Carbohydrate-Electrolyte Solutions) sufficient amount of sodium, although due to the high sugar content they are unpopular with athletes and unsuitable for everyday use. In addition to the analysis and comparison of the various beverages, the authors have enriched non-alcoholic beer with various sodium salts. This shows that it is possible to functionalize alcohol-free beer with sodium salts and thus produce a fully-fledged isotonic sports drink.