Whey proteins and sports nutrition

High concentrations of protein provide an energy source during endurance exercise

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THE past decade has seen increasing popular interest in healthy lifestyles based on regular exercise. This increase in the number of muscle and fitness enthusiasts has prompted a growing consumer demand for protein sports beverages, specialised nutritional drinks, nutritional snack bars and other products designed to optimise athletic performance. A growing body of scientific evidence indicates whey proteins deliver important physiological benefits for consumers seeking superior physical performance and recovery. Specially suited proteins for sport products Whey proteins are both easily digested and have excellent metabolic efficiency, giving the protein a high biological value. They also contain the highest concentration of branched chain amino acids (BCAAs) available from any natural food protein source. During exercise, whole body protein synthesis is decreased, and proteins are mobilised into free amino acids. Skeletal muscles take up BCAAs from the blood and break them down into glucose for energy. Therefore BCAAs are unique amongst amino acids in their ability to provide an energy source during endurance exercise. Whey proteins are specially suited to sports drink and bar formulations. Isolates provide a high concentration of BCAAs (26g per100g protein) high quality pure protein and excellent bioavailable calcium. The use of whey products as ingredients in sports foods has been increasing steadily with improvements in the technological capabilities of the industry to produce commercially attractive whey protein concentrates (WPCs), whey protein isolates (WPIs), and enriched whey protein fractions. Whey protein concentrates are available in various protein concentration levels such as 34% (WPC34), 50% (WPC50) or 80% (WPC80). Whey protein isolates contain more than 80% protein (typically 90%). The key whey products used in sports nutrition bars and drinks are sweet dried whey, WPCs, WPIs, hydrolysed whey products, whey peptides, lactoferrin and other fractions. Protein requirements and sports The American Diet Association (ADA) and other nutritionists associations have reported that1.5g protein per kg body weight, which is considered an adequate amount for athletes, is required for maximum protein deposition (97 to105g of protein per day for a 70kg individual).These protein intakes are recommended for keeping the body in nitrogen balance, or to give a positive balance with increased muscle mass for certain athletes or other individuals requiring more muscle mass. Nutritional considerations of strength/ power athletes participating in bodybuilding, weightlifting, wrestling, and self-defence are different than other sport groups. Nitrogen balance studies indicate levels of protein up to 2.0g per kg body weight per day may be required for endurance and strength/ power athletes to remain in positive balance. Bodybuilders are known to take in large quantities of whey proteins. Some consume higher than 2.0g protein per kg of body weight. They recognise that increasing lean muscle mass requires additional protein intake and demanding bouts of exercise. It does not take much extra protein to supply amino acids for enlarging muscles. However, no protein is 100% utilised. The loss of efficiency in high-quality protein utilisation is about 30%, and in poorer-quality protein, it is about 60%. Ingestion of very high amounts of protein increases metabolic stress to organs. It is clearly much more desirable to eat proteins with the best biological value, such as whey proteins. A rich source of BCAAs Whey proteins contain a high level of BCAAs (~26%) that are taken up directly by skeletal muscles during extensive exercise, rather than first being metabolised through the liver like other amino acids. Since tAdidas Puma Shoes