Chapter 10 Nutrition

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Sport Doping Violations

A Centers for Disease Control (CDC) Youth Risk Behavior Survey found that 6.8% of young male and 5.3% of females use anabolic steroids and that more than 850,000 high school students admit using or having used anabolic steroids. Black Market sales of anabolic steroids exceeds $500 million. More than 1 million Americans, half of them adolescents use black-market steroids and over half of the teen users start before the age of 16. In addition, many of the 6 to 12 percent of boys who use steroids want to be sports champions, but more than one third are not even on a sports team. These products are obviously marketed well. 57% of teen users said that they were influenced by muscle magazines with a readership of > 10 million and 42% were swayed by famous athletes they were convinced used steroids. The risks do not outweigh the benefits and the side effects are as follows: Impotence and testicular atrophy Clitoral enlargement, acne, body hair, deepening voice Gynecomastia (in men). Aggressive behavior If used by adolescents, can cause a permanently shortened stature (long bone growthceases) Highly atherogenic (lowers HDL cholesterol) Liver damage Consuming a substance in abnormal quantities with the intent of artificially and unfairly enhancing sports performance may be perceived as doping. The 1994 IOC Medical Commission banned the administration of substances belonging to selected classes of pharmacological agents as well as the use of various doping methods. The following methods constitute a violation: Substance present in the athlete's tissue or fluid Athlete takes advantage of a prohibited technique Athlete admits having used or taken advantage of a prohibited substance or technique Doping classes Stimulants Narcotics Anabolic agents Diuretics Peptide and glycoprotein hormones and analogs Doping Methods Blood doping Pharmacological, chemical, and physical manipulation Restricted Classes of Drugs Alcohol Marijuana Local anesthetics Corticosteroids B-blockers Specified ß2-antagonists

Sport Food vs. Supplements

Athletes use a variety of products that they believe to enhance their performance. Some are harmless and others have safety concerns associated with them. Sports bars, drinks, and gels are more complex and food-like than products referred to as nutritional supplements which are usually single nutrients or related substances in pill or capsule form. Dietary supplement: a product used to provide nutritional support to the human diet. a). Traditional definition: a product composed of essential nutrients, i.e., vitamins, minerals, and protein. b). Expanded definition (1990): product containing not only essential nutrients, but also may be composed of herbs and other botanicals, amino acids, glandular, metabolites, enzymes, extracts, or any combination of these. Click here for a more detailed definition of a dietary supplement. Sports nutrition products are well marketed. From Forbes: "One of the fastest growing industries in the world is the nutritional supplement group, or more broadly known as Vitamins, Minerals and Supplements, or VMS. Producing about $32 billion in revenue for just nutritional supplements alone in 2012, it is projected to double that by topping $60 billion in 2021 according to the Nutritional Business Journal." Amino acid supplements are among the most popular of all supplements and used by competitive athletes, both professional and amateurs. There are about 25 -30 amino acid supplement ads in any popular body building magazine every month. Athletes use these products for two main reasons: first, because they believe it gives them a competitive edge, and second, it is believed that they build muscle and serve as an energy source. Unfortunately, exercise builds muscle not protein, and carbs are our major energy source. Nutritional supplements have never been regulated by the FDA as they are neither food nor drug. What most people don't realize is that under the Dietary Supplement Health and Education Act of 1994 (DSHEA) that the supplement manufacturer is the responsible party in ensuring a product is safe before it is marketed, and that manufacturers do not need to register with the Food and Drug Administration (FDA) or get approval before marketing their product. The FDA merely regulates the accuracy of the label and responds to complaints against any particular supplement once it is on the market. Also, any product on the market prior to 1994 did not have to be proven effective and will only be removed following investigation of enough complaints. The Federal Trade Commission (FTC) regulates advertising. Research Valid research is lacking for many supplements (one study found only 21% had research to back up claims). Quite frankly, there is a lack of funding because there is no perceived benefit to health or disease prevention. Have you ever heard the motto, caveat emptor? It translates to "Let the buyer beware." In other words, the product you purchase may not contain what it says. Some manufacturers are overly creative and sometimes fraudulent. Check this out and this video! Most supplements fail to make an appreciable difference. Testimonials are not research. We need to look to clinical trials which are published in peer-reviewed journals for more accurate information. Bars, Drinks, and Gels Sports bars, drinks, and gels are formulated for a specific purpose and vary in protein content, carbohydrate source, and fiber content. They generally provide energy nutrients and can be used as partial or full meals. Your textbook lists several on pages 331-332. I think of them as a portable, convenience food when access to more natural foods is limited. Sport shakes are similar in consistency and can be homemade using egg substitute plus nonfat dry milk and frozen yogurt and even a vitamin supplement if desired. You can find a couple of recipes for sport shakes on page 334 as well as a comparison to MET-RX, a commercial version of a sport shake. Sport Drinks can be used as fluid and electrolyte replacement solutions (FER) and/or recovery and loading beverages. The rate of gastric emptying is an important consideration. In general, the recommendation for sports drinks during exercise is about 6-12 ounces every 15 minutes as tolerated. It takes about that long for the stomach to empty and be ready for the next dose. They are especially intended for events that cause heavy sweating at the rate of 2L/hr. The calories they provide can also be glycogen-sparing. Recommendations for FER are based on the size of an athlete. You can find these calculations on p. 336 in your textbook. Sports Drinks Tolerance and absorption rate of sport drinks depends on the temperature and composition (osmolality) of each sport drink and mode of exercise one is participating in. Cooler temperatures at ~50°F or in the range of 5 -15°C tend to increase the absorption rate of a beverage (this goes for water, too). Sports such as running that cause a lot of torso bouncing can delay gastric emptying and increase gastroesophageal reflux (GER). Sport Gels and Glucose Tablets are easy to carry and usually contain 100 Kcal CHO in the form of maltodextrin or fructose. You need an appropriate amount of water to go with these to prevent dehydration. Some may also contain vitamins, antioxidants, and BCAAs. Sport gels are often used as a loading or recovery food.

Supplementation

BEFORE supplementation, make sure you are doing the following for best performance results: Sleep 8 hrs each night Eat 3 meals, beginning with breakfast 8- 12 glasses of water Fruits / Vegetables 300g complex CHO after activity Supplementation for Sport Injury In addition to supplement use for enhancing sport performance, nutrition supplementation is also used for sport injury. Sport injury includes strains, ruptures, tears, and fractures. Eccentric muscle contraction can cause damage to muscle fibers while endurance activities can cause cellular disruption. It is believed that fatigue contributes to injuries in that the greatest number of injuries in team sports, such as soccer occur during the second half of the game or toward the end of a practice session. Repair of damaged tissue is enhanced with adequate intake of energy, protein, vitamin C, copper, zinc, and iron for connective tissue (scar tissue) formation and calcium and vitamin D for bone repair. Use of chondroitin sulfate and glucosamine appears to relieve joint pain in some. There do not appear to be side effects from their use so it does not cause harm to those who wish to try. However, new research shows no alleviation in pain! S-adenosylmethionine (SAMe) and MSM are used similarly to chondroitin sulfate, however, thorough clinical investigation has not been performed. Gelatin is another substance with no proven effectiveness. Omega-3 PUFAs do have some anti-inflammatory effect in blood vessels and it is proposed to benefit joints as well. Other products such as Devil's Claw, white willow bark, D-L-phenylalanine and Boswella Serrata do not have enough research to support their use.

A Dietary Prescription

Dietary Prescription • Helps athletes consume the proper amount of macronutrients within energy needs - Consider carbohydrates and proteins first - Fats and alcohol - Add in discretionary calories • "Discretionary calories" reduced or eliminated • Mild to moderate reduction in dietary fat • Increased energy expenditure • Goal is to not reduce daily intake below 30 kcal/kg • Larger deficits make it difficult to train • Individualized diet plan needed -Eat more snacks and meals daily -Increase portion size of favorite foods -Reduce beverages that do not provide energy but give feeling of fullness like coffee, tea, soda -increase foods in heart healthy fats Consuming Nutrient-Dense Food • Relatively high concentrations of nutrients compared to kcal - Most fruits and vegetables - Whole grains, beans, legumes - Lower fat meat, fish, poultry, and dairy products - Not necessarily low in kcal (e.g., nuts) • Low nutrient dense foods - Sugar - Alcohol - When sugar and fat are added, nutrient density typically declines • Skin milk is a nutrient-dense food because it is rich in nutrients relative to its caloric content • Nutrient-dense foods are an important element in meeting diet planning goals

Flagged Ingredients

For a complete list of banned ingredients, please see the following resources: 1. 2014-2015 NCAA Banned Drugs List 2. The World Anti-Doping Code: THE 2015 PROHIBITED LIST Flagged Ingredients: Paraaminobenzoic acid (PABA) Garcinia Chitosan Ephedra Green Tea Chromium Conjugated Linoleic Acid Inositol Hesperidin complex Yohimbine Bee pollen Lecithins Starch blockers Bitter Orange Forbidden Supplement Combinations: ZMA + Calcium Ephedrine + Caffeine + Yohimbine Creatine + Glutamine L-Carnitine + Yohimbine Creatine + Caffeine Ephedrine + Caffeine + Fat Burners + Pro-Hormones Creatine + Fat Burners The reasons for not using these substances in combination are as follows: Calcium inhibits the absorption of Zinc Creatine and glutamine compete for the same substrate carriers and cotransporters. One wins, one loses. Caffeine inhibits creatine uptake 4-5 hours with caffeine intake and creatine. If you are loading forget caffeine altogether. Yohimbine increases BP and HR which causes an increased load on your heart during exercise. L-Carnitine increases HR and yohimbine stimulates the central nervous system increasing HR similar to creatine and caffeine. Fat burners that contain caffeine or "guarana" (caffeine in herbal form). Dehydration and muscle cramping can result along with increased heart rate. Pro-Hormones increase testosterone (aggression) together and increases adrenaline which stimulates the heart, constricts small blood vessels, raises blood pressure, liberates sugar stored in the liver, and relaxes or contracts certain involuntary muscles. NEVER TAKE TWO INGREDIENTS THAT BOTH INCREASE YOUR HEART RATE.

Energy: The Basis of the Diet Planning

Humans are designed to be biologically active - Active individuals need more kcal - Higher caloric diets make it easier to obtain needed nutrients - Caloric need for athletes can range considerably • Energy needs will vary with training cycle - Usually lowest in the "off-season" - High volume training periods can substantially increase need - Daily intake of no less than 30 kcal/kg is not typically recommended Training types and cal expenditure for males and females : Sedentary- F:30 M:31 Moderate (3-5)- F:35 M:38 Training several hours 5x/wk- F:37 M:41 Rigorous on daily- F:38-40 M:45 Extremely rigorous- F:41-50 M:51-60

Sports Supplements

Sport supplements are marketed to enhance acute performance, increase size, LBM, strength, and possibly enhance the healing process. The amount of research varies to include very few studies on some nutrients to those with more numerous studies and contradictory results. This makes it difficult to make recommendations for the use of most supplements as safe and effective. Have you ever heard the expression, "If a little is good, more is better."? One of the problems with supplement use is that people don't follow the directions on the container and take excessive amounts of a product. This can be especially harmful. Amino Acid Supplementation: Arginine, Ornithine, Lysine supplementation intravenously led to increased growth hormone in burn patients. However, current research in sports nutrition does not support this claim. Aspartic acid is thought to inhibit onset of fatigue during prolonged high intensity exercise by slowing muscle glycogen depletion, but most research contradicts this idea. ß-alanine is becoming of increasing interest as a means to delay fatigue and promote greater levels of work. Research appears promising at this point so this is one to watch. BCAA's, leucine, isoleucine, valine are all essential amino acids utilized for energy by skeletal muscle during endurance and fasting. The ability of BCAA's in supplement form to reduce fatigue during endurance exercise has mixed results. Those studies showing benefit after supplementation for 14 days and/or mixed with other products such as HMB (discussed below). Glutamine has not proven to effectively improve muscle protein production. Note: a combination of essential amino acids (complete protein) such as whey protein isolate can enhance muscle protein synthesis post exercise and can be used to boost the total amount of protein in the diet. Other Popular Supplements: Boron is an essential mineral for bone metabolism and proposed to raise testosterone levels. However, it can also raise estrogen and is not advocated due to lack of proof that it enhances athletic performance. Caffeine has very individualized results. It can affect the CNS by improving alertness and focus, mobilize FFA's, and possibly affect calcium transport and glycogen breakdown. Best results are seen in 100 mg doses three times a day. It is best to experiment during the off season. Doping is considered at levels > 600 mg /day (8 cups) or with urinary excretion >12mcg/ml. Carnitine is used to increase FA utilization and is an ingredient in fat burner products. Most research has failed to show that it can enhance FA utilization or improve performance or body composition. Choline is a component of acetylcholine and lecithin (phosphatidylcholine) in cell membranes. No benefit has been proven. Chromium is a component of glucose tolerance factor (GTF), but does not contribute to LBM, muscle strength, and wt loss. CoQ10 may enhance aerobic metabolism, and may be of benefit as an antioxidant, but researchers do not all agree. Creatine can enhance muscle CP in some, increase LBM, and enhance power performance. It is estimated that 80% of athletes in the 1996 Olympics were using or had been using creatine. A side effect is weight gain however, long-term use is likely safe. This is one of the most widely researched and effective supplements currently in use. DHEA and Androstenedione have no predictable results and may elevate estrogen in males as well as lower HDL cholesterol. Both are banned by the IOC and NCAA. Glycerol may improve hyperhydration efforts but creates the potential for GI discomfort. It should be tried during off-season. ß-Hydroxy-Methylbutyrate (HMB), a metabolite of leucine may increase LBM and strength at the beginning of strength training in untrained people but has little effect on well-trained athletes. Bicarbonate loading may enhance the buffering capacity of extracellular fluid during high-intensity exercise, but may also cause GI discomfort. The results vary in individuals so experimentation should be done during off-season training. Phosphate loading shows results that are unclear but may also cause GI distress and affects Ca:P ratio which could affect calcium status. Lactate loading has little research to support its use for adaptations in lactate metabolism. Oxygen supplementation is done to maximize O2 availability prior to exercise. A small oxygen tank may last 3-20 minutes and is not practical for use in many sports. Its biggest use is in football, American rules and in ice hockey. The above is by no means an exhaustive list of proposed ergogenic aids. ***For a great resource with more detail on supplements, check out Examine.com.

Translating Nutrient Recommendations into Food Choices

Translating Nutrient Recommendations into Food Choices • Guidelines for meal planning - Food Intake Patterns (MyPlate) - Especially useful for those with little knowledge of nutrition - Public domain information • Individualizing a diet plan - The key to diet planning - May involve a new dietary pattern - May involve modification of current diet Food and Fluid Intake Prior to Exercise • All guidelines are subject to trial and error • Timing - Work backwards from time of exercise onset (if known) - Adjust volume of food and fluid based on time • Carbohydartes - 1.0 g/kg body weight 1 hr prior, 2.0 g/kg 2 hrs prior, etc. - Depends on gut tolerance • Protein and fat - Some protein is usually included - Fats provide satiety but must allow for slow absorption • Adjust pre-training guidelines for pre-competition intake • The wrong pre-competition meal is more detrimental than the right pre-competition meal is beneficial! Food and Fluid Intake During Exercise Food and Fluid Intake After Exercise • Begin recovery strategies as soon after exercise as practical; cell sensitivity/permeability is high • Carbohydrate - Muscle glycogen synthesized at highest rate immediately after exercise - Two-hour delay results in substantial reduction of muscle glycogen resynthesis - ~ 1.5 g/kg body weight in first hour post-exercise - Medium to high glycemic index foods are beneficial - ~ 0.75 to 1.5 g/kg each hour over next three hours • Intake immediately after exercise is beneficial • At least 6 g of indispensable amino acids needed • ~ 0.1 g/kg indispensable amino acids • Be practical (e.g., chocolate milk, turkey sandwich) • Intake immediately after exercise is important • ~ 1.5 L (1,500 ml) fluid per kg of body weight lost • Consume enough fluid to be euhydrated before next exercise session • Replenish lost electrolytes (e.g., sodium)

Introduction

Without a doubt, athletes who eat wisely can delay fatigue, enhance their performance, and improve their health. Yet, many athletes and casual exercisers alike eat the wrong foods at the wrong times. Many active people train really hard to improve their performance but fail to get the most out of their workouts. Nutrition is their missing piece. It is important when working with athletes to provide them with accurate information to help them fuel their bodies for sports and health, improve their nutritional fitness, enhance their sports performance, and win with good nutrition. An ergogenic aid is anything believed to enhance sport performance. (Ergo = energy and gen = generate or produce). Most ergogenic aids can affect only one thing at a time. There are way too many products on the market and not enough research. One problem is that research is overwhelming. It is expensive and time consuming. Besides, if you are making money selling a product, why would you care if it actually worked? "Foods first" should be your emphasis when working with athletes since other factors in foods help with absorption of nutrients (such as lactose and vitamin D which both help us absorb calcium from milk). Foods are far superior in nutrition and bioavailability and generally lower in cost. Much research is needed to determine the contribution of vitamins and minerals to athletic performance so to push any kind of supplements first may not even be safe. There are a few exceptions to this rule, such as vegetarians who may need vitamin B12. In this module we will discuss the pros and cons of supplement use by athletes.


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