Sports Nutrition Protein.docx

 Chapter 5: Protein Friday, February 16, 2024 9:08 AM Proteins 1. Amino acids linked together 2. Composed of a. Carbon b. Hydrogen c. Oxygen d. Nitrogen 3. All AA have a similar structure a. Attached to C atom i. H ii. Amino group NH2...

 Chapter 5: Protein Friday, February 16, 2024 9:08 AM Proteins 1. Amino acids linked together 2. Composed of a. Carbon b. Hydrogen c. Oxygen d. Nitrogen 3. All AA have a similar structure a. Attached to C atom i. H ii. Amino group NH2 iii. Carboxylic acid group COOH iv. Side group R = gives AA unique identity   Protein Structure 1. AA joined by peptide bonds through condensation reactions 2. 2 AA joinedà the carboxylic acid group of 1 AA is matched with the amino group of another 3. Primary structure a. Chain of AA b. Sequence of AA determines the shape c. Shape determines function of protein within bod 4. Secondary structure = coils Alpha helix a. Beta pleated sheets 5. Tertiary structure = folds 3D shape caused by weak interactions among R groups, and between R groups 6. Quaternary structure = arrangement of multiple tertiary structures series f polypeptide chains making a protein   Hydrolysis in a High Protein Diet 1. Chemical process that uses water to break peptide bonds 2. Excessive protein intake requires additional hydrolysis to break the peptide bonds of proteins from the diet 3. Digestion of high protein diets à water loss + dehydration if fluid intake is inadequate   180/2.2 = 81.8182 x 2=163.6364 180/2.2 = 81.8182 x 1.2=98.1818 180/2.2=81.8182 x 2 = 2 81.8 x 2=   Amino Acids 1. 20 AA 2. 9 essential AA from diet a. Histidine b. Isoleucine c. Leucine d. Lysine e. Methionine f. Phenylalanine g. Threonine h. Tryptophan i. Valine 3. 11 non-essential AA can be made in body a. Alanine b. *Arginine*\* c. Asparagine d. Aspartic acid e. *Cysteine\** f. Glutamic acid g. Glutamine h. Glycine i. Proline j. Serine a. *Tyrosine\** 4. Conditionally essential AA a. Tyrosine i. needed for the production of melanin +thyroid hormone, the regulation of blood pressure, and the functioning of neurotransmitters such as dopamine and epinephrine. ii. normally, the body makes tyrosine from the essential acid phenylalanine\-- if you don't consume enough phenylalanine in the diet, it's possible to become deficient in tyrosine b. Cysteine i. Needed collagen and neurotransmitter production and for keratin which keeps skin, nails, and hair healthy ii. May be conditionally essential for some infants, seniors, and people with certain metabolic conditions c. Arginine i. Assists with heart health, blood flow, and glucose metabolism ii. individuals conditionally essential = premature infants , individuals with certain diseases or severe physical stress, and young individuals experiencing growth spurts. 5. Eat a varied diet of fish, poultry, and soybeans will help with nearly all of the conditionally essential amino acids, and nuts and seeds like almonds and pumpkin and sunflower seeds can aid in the production of arginine, cysteine, and tyrosine.   Number of Amino Acids 1. Dipeptide = 2 AA 2. Tripeptide = 3 AA 3. Oligopeptide = 4-10 AA 4. Polypeptide = more than 10 AA   High-Quality Protein 1. Complete protein 2. Contains extra AA for protein synthesis 3. Good digestibility 4. Animal-derived foods usually   Low-Quality Protein 1. Incomplete protein 2. One or more limiting AA 3. Usually from plant-derived foods   Complete vs Incomplete 1. Quality depends on how many essential AA are supplied a. Availability of essential AA is a limiting factor when building new proteins 2. Complete protein a. Supplies 9 essential AA b. Animal (eggs dairy meat fish), soy protein quinoa (nearly) 3. Incomplete low in 1 or more essential AA   Complimentary Proteins 1. 2 incomplete proteins can be consumed to result in a complete 2. Combinations should occur in same day, does not need to be same meal 3. Overall protein quality not usually an issue, when food is abundant even those who do not consume 4. Variety of plant foods are consumed one can get a complementary array of incomplete proteins to ensure the necessary intake of essential amino acids 5. plant foods, with the exception of soy, will have at least one limiting amino acid 6. legumes have the limiting amino acids methionine and tryptophan but supply isoleucine and lysine 7. Rice has the right profile to complement the beans because it supplies methionine and tryptophan 8. beans complement the rice by making up for its limiting amino acids of isoleucine and lysine 9. Because animal and soy products contain high levels of all essential amino acids, they can be consumed with any grain, legume, or nut/seed to result in a complementary protein combination. 10. Grains and legumes complement one another 11. legumes and nuts/seeds make complementary pairs 12. grains are not a complementary match to nuts/seeds                             Protein Functions 1. Tissue building 2. Cell functioning = enzymes 3. Body functioning a. Hormones b. Immune function (antibodies = proteins) 4. Fluid balance 5. Acid-base balance 6. Energy source 7. Cellular signaling 8. Transport = lipoproteins     Nitrogen Balance 1. Only found in protein 2. Used as a marker of protein in the body 3. N balance is an indicator of nitrogen status 4. N in - N out = N balance   Determining Nitrogen Balance 1. Studies compare N in vs N out 2. Protein loss a. External hair skin nails b. Cellular metabolism releases N i. Small lost as ammonia ii. Most excreted as urea: urine + sweat   Nitrogen Equilibrium 1. N intake (consumed) = N output (loss) 2. Occurs in healthy adults when intake equals excretion Positive Nitrogen Balance 1. Intake \> output 2. Body retains Nitrogen a. Pregnancy a. Growth b. Muscle building 1. Retain N to build new blood, muscle, and bone cells 2. Adequate calories and protein consumed   Negative Nitrogen Balance 1. N intake \< output 2. When athletes do not consume enough calories or protein to meet needs a. Body proteins used for energy and increase nitrogen loss b. Impairs performance 3. Illness or injury a. Triggers release of powerful messengers that signal the body to break down some less vital proteins (of the blood skin and muscle) b. Surgery patients 4. Space flight a. Stress and lack of gravity (no need to support the body\'s weight) causes astronauts muscles to waste and weaken   Nitrogen Status Goals for the Athlete 1. Supply enough AA to support basic needs + increased needs for protein synthesis due to training and competition 2. Minimum goal of N equilibrium 3. Optimal goal of positive N balance 4. Accomplished via adequate daily calories and protein   Sample Calculation - Recommendations for Ron, moderate training 190 lbs. - 190/2.2=86.3636 kg - 86.3636 x 1.2 = 103.6363 - 86.3636 x 2 = 172.7272 - 104-173g protein/ day   -Position Statement of the International Society of Sports Nutrition, which suggests that exercising individuals consume approximately 1.4 to 2.0 g of protein per kg of bodyweight per day.     Sample Calculation - Ron 3200 calories/ day, how many from protein - 15-35% - 3200x.15=480 - 3200x.35=1120 - 480-1120 calories/ day from protein - 480/4 = 120g - 1120/4=280 - 120-280g based on caloric intake   Factors Influencing Protein Requirements 1. Total energy intake a. Protein that is not used for energy can be used to perform important functions = rebuild/ repair athlete tissues b. Athletes tend to consume adequate protein within calories c. If caloric intake is sufficient, recommendations can fall in the middle of recommended ranges 2. Desire to lose or gain weight a. Preserve lean body mass b. Assist in muscle synthesis and repair to increase lean body mass c. Increase/ higher end of recommendation 3. CHO availability spares muscle protein breakdown 4. Exercise intensity and duration a. Increasing intensity/ physical demand + increasing duration b. Higher recommendation c. Using protein for energy as carbohydrate stores are depleted during endurance d. increased need for protein for muscle repairs and contractions during resistance training 5. Training status/ fitness level a. Returning to training after time off, higher needs then return to normal level 6. Dietary protein quality a. Animal sources b. Vegan vegetarian should consume higher protein   Protein of the Athlete Age 1. children and teens need protein to not only address the demands of physical activity, but to support growth, especially during growth spurts. 2. older adults have higher protein needs than younger adults their intake of protein may be challenged by physiological, environmental, economic, and other barriers often found among older adults. 3. that nutrition professionals should work with individuals to determine individualized strategies obtain nutrient dense sources of foods across the lifespan   Protein in Injury Recovery 1. support the healing process for athletes recovering from injury 2. Repair damaged tissues 3. Minimize skeletal muscle loss (atrophy) from disuse immobilization 4. 2.0 g/kg or higher in 20 g to 30 g doses over the course of the day and that food sources of branched chain amino acids are ensured 5. Branched chain AA = leucine, isoleucine, valine a. Can be metabolized directly within muscle as source of energy, do not need to be converted to glucose in liver prior to being delivered by the blood to muscle b. Role in muscle protein synthesis c. Sources = dairy, meat, wheat protein and soy, whey protein isolates   Overconsumption of Protein 1. Recommend not to exceed 35% of calories from protein 2. Higher amounts a. Do not appear to contribute to liver or kidney issues b. Do not appear to contribute to osteoporosis c. DO displace carbohydrates i. Counterproductive to physical and performance goals ii. May lead to dehydration   Meeting Protein Needs 1. More than 30g of protein at one time exceeds the body\'s capacity to use protein for functions of repair, synthesis, anabolism 2. Excess amounts are denitrogenated and used for energy/ stored as fat 3. Important to spread protein throughout the day     Athletes and Protein Supplementation 1. Most athletes consume enough protein 2. Can and should focus on whole foods to meet needs 3. Supplements may benefit athletes with very high caloric + protein needs 4. Useful during travel on the go, should not be chosen over whole foods 5. Whole foods with all essential AA, EAAS required to stimulate muscle protein synthesis   Questions about Supplements 1. Quantity of protein of AA in product? 2. Is it necessary? 3. More than 30g has no benefits for anabolic purposes 4. How does amount of protein or AA compare to whole foods? 5. What is the cost? 6. Will it enhance performance? No evidence 7. Harmful effects? a. AA compete for absorption b. Excess amounts may decrease the absorption of others c. Ex: allergens, chemicals, additives, side effects 8. Ingredients banned in athlete\'s sport? 9. Choosing a supplement a. Complete whey protein b. Low in added sugar c. 3rd party certified     Protein and Training 1. Energy for training and competition a. Carbs and fats are main sources b. Protein contributes \~5% c. 15-18% during prolonged exercise d. Occurs through oxidation + gluconeogenesis i. Gluco-alanine cycle 2. Training and competition increase protein needs a. Causes changed in protein and AA metabolism b. Cause increase breakdown of muscle tissue 3. Insufficient intake, endogenous proteins will be used and decrease performance or cause illness 4. Low intake during intense training may contribute to sports anemia a. Low levels of hemoglobin in blood due to insufficient intake of AA + expanded plasma volume associated with endurance training b. Does not significantly alter performance 5. Adequate calories + carbs needed to spare dietary protein     Athlete Eating 4-24 Hours Prior to Exercise 1. High CHO meals/ snacks a. My plate b. Athletes\' plate 2. Carbs should predominate, not proteins 3. Choose familiar foods 4. Avoid excessive fiber intake if not well-tolerated 5. Lean protein sources a. 3-6oz turkey, fish, soy b. 8-12 oz dairy c. Complementing low-fiber plant sources   Athlete Eating 1-4 Hours Prior to Competition 1. Focus on CHO 2. Small amounts of protein 2-4oz lean meat 3. Lean sources preferable 4. Avoid high fat sources of protein (nuts, full-fat dairy, high-fat meats) a. Takes longer to digest\--\> discomfort   Protein Consumption During Competition 1. Can serve as energy source 2. Slow process for most AA 3. BCAAS metabolized within muscle itself, not processed by liver a. Inconsistent research of use to delay fatigue during exercise     Protein After Competition 1. Critical for post-exercise recovery 2. As soon as possible, or consume in at least 2-3 hours after 3. Essential AA are key a. Foods supplying complete profile whey and casein within milk b. Whey and casein have higher levels of BCAA i. Leucine noted aid in repair c. Soy protein offers all EAAs 4. Hydrolyzed Protein a. Typically in supplement form b. Undergone a pre-digestion process to result in di- and tripeptides c. Absorbed more quickly than intact proteins or supplements composed of primarily free AA i. Differences in absorption rates are least noticeable among well-nourished athletes 1. Higher for individuals who are fasting or on low-calorie diets ii. Consumption of EAA emphasized regardless of form 5. 15-25g or 0.25-0.30g protein/ kg 6. Research supports intake of protein and carbs post-exercise within 2-3 hours after competition a. Maximizes glycogen synthesis b. Promotes secretion of hormones aiding in muscle growth c. Enhances protein synthesis 7. Examples of post-exercise meals and snacks page 139