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Chapter 22. Ergogenic Aids. Objectives. Define ergogenic aids Understand amino acid supplementation Understand caffeine supplementation Understand creatine supplementation Describe hydration mechanics Describe nutrient timing. Introduction.
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Chapter 22 Ergogenic Aids
Objectives • Define ergogenic aids • Understand amino acid supplementation • Understand caffeine supplementation • Understand creatine supplementation • Describe hydration mechanics • Describe nutrient timing
Introduction • Ergogenic aids are substances (including nutrients, nutritional supplements, and drugs) that improve athletic performance • Several ergogenic aids have been shown to have a positive effect under specific conditions
Branched-Chain Amino Acids • The amino acids leucine, isoleucine, and valine are collectively known as the branched-chain amino acids (BCAAs) • Supplementation with BCAAs does not appear to improve short-term exercise performance but may reduce muscle breakdown during clinical conditions of wasting and periods of prolonged exercise
Branched-Chain Amino Acids (cont.) • Men and women who ingest approximately 10-15 g of BCAAs per day for at least 30 days increase their lean body mass more than do matched controls • BCAAs may have positive ergogenic effects related to their anticatabolic effect; however, fairly large doses must be consumed to achieve this
Caffeine • Caffeine is an effective ergogenic aid; it may promote lipolysis, stimulate the central nervous system, and act as a performance-enhancing aid for many types of athletic activity • Caffeine has been removed from the World Anti-Doping Agency’s banned list
Colostrum • Colostrum is a component of breast or cow’s milk; it is found at its highest concentration 2 to 3 days after a female gives birth • It is a rich source of protein, antibodies, and growth factors
Colostrum (cont.) • Several compelling studies demonstrate an ergogenic effect of colostrum supplementation • Such supplementation combined with aerobic and heavy resistance training significantly increased bone-free lean body mass compared to whey protein
Creatine • Creatine is a naturally occurring nitrogenous compound made in the liver, kidneys, and pancreas from the amino acids arginine, glycine, and methionine • Is absorbed into the bloodstream through the small intestine and reaches peak levels at 60 to 90 minutes
Creatine (cont.) • Creatine is thought to serve at least four vital functions: • 1. Stores energy that can be used to regenerate ATP • 2. Enhances energy transfer between the mitochondria and muscle fibers • 3. Serves as a buffer against intracellular acidosis during exercise • 4. Stimulates glycogenolysis during exercise
Creatine (cont.) • Of the well-controlled human trials on creatine, about two thirds have shown benefits from its use • Depending on the initial fitness level of the subjects, these have included the following • Increased dynamic strength and power • Increased body weight and lean body mass • Increased sprint performance
Creatine (cont.) • Creatine supplementation has a “significant positive effect on both working memory and intelligence” • The only consistently reported “side effect” in humans has been weight gain • Neither short, medium, nor long-term oral creatine supplementation causes detrimental effects on the kidneys of healthy individuals
Creatine (cont.) • Athletes considering creatine use should exercise the following precautions: • Do not “load” • Cycle period of use with periods of nonuse • Purchase the product from a reputable manufacturer who is able to provide a “certificate of analysis”
Essential Amino Acids • Of the 20 amino acids used to form proteins, 8 are considered essential amino acids (EAAs) • A growing body of literature demonstrates the efficacy of essential amino acid supplementation in enhancing physical performance • Essential amino acids play a critical role in promoting skeletal muscle anabolism
Glucosamine • Combination of glutamine and glucose • Can repair damaged cartilage and make new cartilage • Regular consumption of glucosamine may alleviate the signs of osteoarthritis (OA) • May provide some degree of pain relief and improved function in persons experiencing regular knee pain
Glutamine • Most plentiful nonessential amino acid in the human body, particularly in the plasma and skeletal muscle, and has numerous physiological functions • Has been widely used by weight trainers because of its muscle building potential
Glutamine (cont.) • Has been shown not only to increase protein synthesis but also to stimulate glycogen synthesis • Glutamine’s role as an ergogenic aid as it relates to immune function may be of greater significance to athletes than its ability to increase muscle mass
Glycerol • Regular exercise can cause fluid loss, that if not replaced, can potentially compromise performance and/or the next exercise session • The most common method of “hyperhydration,” a condition in which body water stores are temporarilyelevated, is the consumption of glycerol
Glycerol (cont.) • Glycerol ingestion causes an increase in fluid absorption by the blood and tissues, prolonging hyperhydration for up to 4 hrs. • Has also been used to treat cerebral edema and glaucoma • Headache and blurred vision sometimes accompany glycerol use
Green Tea Extract • Green tea extract has a high content of caffeine and catechin polyphenols, which could increase 24-hour energy expenditure and fat oxidation in humans
Green Tea Extract (cont.) • Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content • Green tea extract may play a role in the control of body composition by thermogenisis, fat oxidation, or both
HMB • Beta-hydroxy-beta-methylbutyrate (HMB) is a natural component of fish and milk • HMB is thought to increase strength and lean body mass by acting as an anticatabolic agent in muscle • Ingestion of HMB appears to be safe and may even have beneficial effects on cardiovascular health when doses of 3g/day are ingested for up to 8 weeks
Hydration • Dehydration has negative effects on performance (1-2% water loss; 5-6% is bad) • Inadequate hydration can refer to either hypohydration (being dehydrated prior to exercise) or exercise-induced dehydration, which occurs during exercise
Hydration (cont.) • Water and sports drinks can be very effective in maintaining performance or delaying the inevitable decrease in performance, especially in endurance or team sports that last longer than 1 hour • Without proper fluid replacement during prolonged exercise or exercise in a hot and humid environment, heat-related illness and cardiovascular issues can become life-threatening
Hydration (cont.) • Complete restoration of fluid lost during exercise cannot occur without replacement of electrolytes, primarily sodium • Inclusion of carbohydrates in rehydration solutions is necessary to maintain blood glucose concentrations for optimal performance in exercise lasting longer than 1 hour
Pre- and Postworkout Nutrition • Strenuous exercise can reduce various energy substrates, increase muscle protein breakdown, damage cell membranes, cause fluid loss, and temporarily impair immune function • A successful pre-exercise strategy is to provide a small amount of carbohydrate along with 6 g of essential amino acids approx. 15 min before resistance training
Pre- and Postworkout Nutrition (cont.) • This specific combination of carbohydrates and essential amino acids has been shown to increase muscle protein synthesis 160% more than ingesting the same cocktail post-exercise • Only essential amino acids are needed to promote anabolic processes in muscle
Pre- and Postworkout Nutrition (cont.) • Nutrition during the post-exercise period accomplishes three goals: • 1. Puts the brakes on protein degradation • 2. Increases muscle protein synthesis • 3. Rapidly initiates the process of muscle glycogen regeneration
Pre- and Postworkout Nutrition (cont.) • A carbohydrate-to-protein ratio that ranges from 4:1 to approx. 1:1 may expedite recovery as well as enhance muscle glycogen synthesis and net protein status • Many athletes find that adding 3-5 g of creatine and 5-10 g of BCAAs to their pre- and post-workout beverages provides an enormous benefit
Pre- and Postworkout Nutrition (cont.) • Myostatin blockers have been purported to enhance muscle hypertrophy • Nitric oxid stimulators are currently popular to build muscle mass but controlled research studies have not demonstrated a benefit from the supplement • Illegal substances such as anabolic-androgenic steroids are commonly used
Next Class • Chapter 10 Resistance technique • Homework-Chapter 22