Optimal Composition of Fluid‐Replacement Beverages

Abstract

The objective of this article is to provide a review of the fundamental aspects of body fluid balance and the physiological consequences of water imbalances, as well as discuss considerations for the optimal composition of a fluid replacement beverage across a broad range of applications. Early pioneering research involving fluid replacement in persons suffering from diarrheal disease and in military, occupational, and athlete populations incurring exercise- and/or heat-induced sweat losses has provided much of the insight regarding basic principles on beverage palatability, voluntary fluid intake, fluid absorption, and fluid retention. We review this work and also discuss more recent advances in the understanding of fluid replacement as it applies to various populations (military, athletes, occupational, men, women, children, and older adults) and situations (pathophysiological factors, spaceflight, bed rest, long plane flights, heat stress, altitude/cold exposure, and recreational exercise). We discuss how beverage carbohydrate and electrolytes impact fluid replacement. We also discuss nutrients and compounds that are often included in fluid-replacement beverages to augment physiological functions unrelated to hydration, such as the provision of energy. The optimal composition of a fluid-replacement beverage depends upon the source of the fluid loss, whether from sweat, urine, respiration, or diarrhea/vomiting. It is also apparent that the optimal fluid-replacement beverage is one that is customized according to specific physiological needs, environmental conditions, desired benefits, and individual characteristics and taste preferences.

The Effects of Carbohydrate Mouth Rinse Concentration on Cycling Time Trial Performance

“…The American College of Sports Medicine Position Stand (Sawka et al, 2007) and Baker and Jeukendrup (2014) recommend consuming a fluid replacement beverage of 6-8% CHO such that 30-60g (Sawka et al, 2007) and up to 90g (Baker & Jeukendrup, 2014) are ingested per hour of exercise. They also recommend that several types of CHO be consumed to maximize total CHO absorption (Baker & Jeukendrup, 2014;Sawka et al, 2007).…”

“…The American College of Sports Medicine Position Stand (Sawka et al, 2007) and Baker and Jeukendrup (2014) recommend consuming a fluid replacement beverage of 6-8% CHO such that 30-60g (Sawka et al, 2007) and up to 90g (Baker & Jeukendrup, 2014) are ingested per hour of exercise. They also recommend that several types of CHO be consumed to maximize total CHO absorption (Baker & Jeukendrup, 2014;Sawka et al, 2007). It is important for the athlete to train using CHO drinks if they plan to compete with them because at high intensities, sports drinks are associated with impaired gastric emptying and an increased chance of gastric distress (Baker & Jeukendrup, 2014;van Nieuwenhoven et al, 2004).…”

“…They also recommend that several types of CHO be consumed to maximize total CHO absorption (Baker & Jeukendrup, 2014;Sawka et al, 2007). It is important for the athlete to train using CHO drinks if they plan to compete with them because at high intensities, sports drinks are associated with impaired gastric emptying and an increased chance of gastric distress (Baker & Jeukendrup, 2014;van Nieuwenhoven et al, 2004). Even with this side effect as a possibility, CHO are still recommended during prolonged activity.…”

Why do team-sport athletes drink fluid in excess when exercising in cool conditions?

“…Fluid balance is important for optimal physiological functioning, health and exercise performance (Baker and Jeukendrup 2014). Comprehension of the mechanisms that regulate fluid balance in varying sporting and environmental situations is vital to ensure the implementation of appropriate hydration strategies.…”

El consumo de leche posterior al ejercicio disminuye la excreción de electrolitos / Milk Consumption After Exercise Decreases Electrolyte Excretion

“…Por lo señalado anteriormente, es de gran importancia escoger una bebida rehidratante apropiada, donde una correcta combinación de macronutrientes y una adecuada selección y cantidad de electrolitos es fundamental (Casa, Clarkson & Roberts, 2005;Mayol & Aragon, 2009). Una correcta combinación de nutrientes permite recuperar la volemia y optimizar la rehidratación celular (Baker & Jeukendrup, 2014). Actualmente existe una gran variedad de bebidas isotónicas en el mercado, conocidas como "bebidas deportivas".…”