Dietary supplements and nutrition in sports and exercices performance

Transcription

1 Dietary supplements and nutrition in sports and exercices performance

2 Nutrition for endurance sports The most likely contributors to fatigue during an endurance exercise are dehydration and carbohydrates depletion. In addition, hyperthermia, hyponatremia and gastro intestinal problems can reduce endurance performance. What endurance athletes have to improve to get better results? Endurance athletes aim to improve their energy production, adiposity melt, health conditions, recovery and endurance. Some factors can also be improve performance of endurance athletes such as the anaerobic threshold, the rate of fatigue, the VO2 max, the oxidative stress and the maximum anaerobic power and speed. In addition, hydration state and oxidative stress are important factor of decreasing of performance. What endurance athletes should ingested to improve their performance? Caffeine is one of the most common supplements used in endurance sports. The recommended doses are in the red beet concentrate juice can enhance endurance by increasing blood flow. Gastro intestinal problems were most likely to occur with carbohydrates ingestion of fibre, fat, proteins and concentrated carbohydrates solutions during an event. To optimize endurance exercise, carbohydrates and fluids play an important role. During intense exercise lasting longer than one hour, carbohydrates should be consumed at a rate of 30 to 60 g/h to maintain oxidation of carbohydrates and delay fatigue. This may be accomplished by drinking 600 to 1200 ml/h of fluid solutions containing 4 to 8 % carbohydrates as sugars (sucrose or glucose) or starch (maltodextrin). Sugars drinks need not to be consumed during moderate exercises. Sports drinks generally contain 2 to 8% sugars. Nutrition for power sports: middle distance running, track cycling, rowing, canoeing/kayaking and swimming What power athletes have to improve to get better results? Some power sports feature highly technical components: swim or row stroke technique. The primary focus for power athletes is the recovery of muscle energy stores (primarily glycogen) and the synthesis of new proteins. Since muscle glycogen is the primary fuel for power athletes and clear evidence suggests that low pre exercise muscle glycogen concentrations result in reduced high intensity performance, glycogen re synthesis after training or competition is of importance. Thus, power athletes aim to improve strength, energy production, health, and some factors such as anaerobic threshold, maximal anaerobic power and speed, VO2 max. Moreover, decrease oxidative stress because of high intensity exercises and improve recovery can help power athletes to get better performances. What power athletes should take to improve their performance? There are two supplements that power athletes can potentially utilize to augment buffering capacity and potentially improve performance: The prolonged supplementation of beta-alanine to increase muscle carnosine content to enhance intracellular buffering. Results confirmed that muscles contenting more carnosine can generate more powerful and more durable contractions. It is recommended to consume 2 to 3 g in drinks pre and post workouts. The acute supplementation of sodium citrate or bicarbonate to enhance extracellular buffering. Carbohydrates intake during training can not only assist in providing energy but also neuromuscular support can reduce technical errors and enhance skills development. Since muscle glycogen is the primary fuel for power athletes and clear evidence suggests that low pre exercise muscle glycogen concentrations result in reduced high intensity performance, glycogen re synthesis after training or competition is of importance.

3 Nutrition for team sports Field games can be subdivided into: Strength and power sports, such as American football, rugby union and rugby league Endurance based sports, like soccer, field hockey, Australian and Gaelic football, lacrosse Batting sports, such as cricket, baseball, and softball The most popular and beneficial supplements for team sports are sports beverages and caffeine. Creatine is also popular among team sport athletes but a controversial item to both scientists and practitioners. Creatine alone or combined with protein powders is very popular in strength and power sports, although some players complain about tight muscles or muscle tears when on creatine. As a strategy to prevent unwanted purported side effects, European professional soccer teams sometimes supplement creatine in low doses of 2-3g/d, avoiding the acute loading phase of 20g/d for 5 days. Nutrition for team sports requires knowledge of the sport specific physiology of training and competition coupled with social skills to be able to implement dietary recommendations within the framework of a multi professional sport science and medicine group and coaching staff. An individual approach is needed to meet each athlete s nutritional and hydration needs. Rehydration with alanine-glutamine appears to maintain basketball skill performance and visual reaction time to a greater extent than water only. These effects are likely mediated by enhanced fluid and electrolyte uptake from the gut and subsequent preservation of the neural function that commands physical activities involving fine motor control. Nutrition for bodybuilding and strength sports What strength athletes and bodybuilders have to improve to get better results? In strength sports and bodybuilding, strength, lean body mass, weight gains, adiposity melt are the main factors that have to be improved. What strength athletes and bodybuilders can take to improve their performance? Proteins are the most common supplement in strength and bodybuilding sports. The best source of proteins is obviously whey proteins, egg proteins, and caseins. It is recommended to take 20 to 40 g of caseins between meals or at sleep, 20 to 50 g of egg proteins between mels, and 20 to 40 g of whey proteins in the morning, 30 minutes before a workout, after a workout and between meals. Creatine monohydrate stimulates increase in lean body mass, strength gains and contributes to maintaining of creatine phosphate into muscles which is an important source of energy in muscles. It is recommended to take 2 to 5g of creatine pre and post workout during a limited period of time. HMB (beta-hydroxy-beta-methlybutyrate) is a leucine metabolite. The anabolic gains achieved by stimulating the muscles through training are offset by the catabolic effects of frequent, high intensity workouts. HMB s anti catabolic effects might move this balance point further in the direction of anabolic growth allowing an individual to train more often and still receive positive results in strength and mass gains. The BCAA, especially leucine, are particularly important since they contribute as energy substrates and as nitrogen donors in the formation of alanine, glutamine and aspartate. Results indicate an increased supply of BCAA might have a sparing effect on muscle glycogen degradation during exercise. Long term exercise following BCAA administration results in significantly greater muscle nitrogen, alanine and glutamine production as well as lower lactate production. Glutamine is the most abundant amino acid in the blood and in the free amino acids pool of skeletal muscle. Glutamine stimulates the synthesis and inhibits the degradation of proteins, is an important vehicle for the transport of nitrogen and carbon within the tissues, stimulates the synthesis of hepatic glycogen and is an energy source for cell division.

4 Performances looked for and corresponding dietary Performances looked for Increase lean body mass and muscle hypertrophy Increase muscle strength Improve anaerobic threshold Improve recovery Improve endurance Decrease rate of fatigue Decrease oxidative stress Improve Maximum Aerobic Power Improve VO2max Improve Maximum Aerobic Speed Maintain hydration state Maintain agility and skills Helped dietary supplementations Proteins (Whey, Soy, Caseins), EAA, Beta-alanine, Creatine, HMB and Chromium Creatine, HMB, ZMA, Hydroxymethylbutyrate Sodium phosphate, Sodium bicarbonate Proteins, ZMA Caffeine, Sodium phosphate, ViNtrox, BCAA, Octacosanol Beta-alanine, Aspartate and Asparagine Vitamin A and E, Carotenoids, Coenzyme Q10, ViNitrox Creatine, Beta-alanine, Sodium bicarbonate L-carnitine Sodium phosphate Glycerol, L-alanyl-L-glutamine Vitamin B6 (in conjunction with vitamin B1 and B12), Caffeine and Octacosanol

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