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PROTEIN. Proteins and Amino Acids. Made of carbon, hydrogen, oxygen, and nitrogen Amino group (NH 2 ) & Carboxylic group (COOH) make backbone Side groups make the difference. Side Chain. PeptideBond. Backbone. Leucine. Tyrosine.
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Proteins and Amino Acids • Made of carbon, hydrogen, oxygen, and nitrogen • Amino group (NH2) & Carboxylic group (COOH) make backbone • Side groups make the difference
Side Chain PeptideBond Backbone Leucine Tyrosine COOH NH2
Amino Acids • Linked in certain sequence • dipeptides = 2 A2 • tripeptides= 3 A2 • polypeptides= 4 or more • most contain hundreds of A2 A2 = Amino Acids
Structures • Primary • Unique sequence • Secondary • Shape along one dimension • Tertiary • 3-dimensional shape • Quaternary • Joining of 2 or more 3-dimensional polypeptides into larger protein molecules
Essential Amino Acids • Cannot be synthesized • Nine A2 are essential • Some nonessential are essential during stress • glutamine, alanine, carnitine • Peptide bonds join A2 • Body protein makes you different
Protein • Part of every cell • Do cell’s work • Determine nutritional status • Part of antibodies • enzymes • hormones • structural materials
Protein Function • Repair and building • collagen mending material • Energy if not enough CHO • supplies 4 kcal/g
Enzymes • All are proteins • Function as catalysts • join and dismantle • Unchanged during enzymatic action
Fluid Balance • Maintain body’s fluid balance • Fluids are in 3 major compartments • inside blood vessels • within cells • surrounding cells • flow is back and forth
Fluid Balance • Proteins and minerals in fluids help to maintain distribution among spaces • Albumin is big regulator • Maintains osmotic pressure • Prevents fluids from leaking out of cells into intercellular spaces
Fluid between cells Intercellular or Interstitial Fluid within the Cell Intracellular Fluid within blood vesselsIntravascular
Acid-Base Balance • Albumin and friends prevent imbalances • Acids and bases created by normal body functions • Removed by kidneys (bicarb) or lungs (carbonic acid)
Acid-Base Balance • If kidneys and lungs fall behind, proteins gather or release extra H2 ions • Called buffering • Why? • Too much acid or alkaline can denature protein • Cooking is also a way of denaturing
Acid-Base Balance • pH tightly regulated • Imbalances are acidosis or alkalosis • Can be respiratory or metabolic
Protein Function • Antibodies • against viruses and bacteria • Messenger • thyroid and insulin • Transport proteins • move nutrients in and out of cells • hemoglobin and lipoproteins • carry vitamins and minerals
DNA • Deoxyribonucleic acid-in every cell • Genetic codes in DNA • Metabolic pool • A2 not stored • Limited amount available in Metabolic pool for “daily use” • Protein Turnover • Constant breakdown/synthesis of endogenous proteins • Exogenous=from food • Endogenous=from protein tissues
Nitrogen Balance • Positive N2 balance or equilibrium means eating what you need • growth, pregnancy, healing • +2-4 g/day • Negative N2 balance means not enough protein or CHO • stress and trauma • auto digestion of muscles and organs
Energy • Energy of last resort • No specialized storage form • Only muscles and organs • Energy deprivation or starvation • Wasting of lean body tissue • Fat loss
Protein Energy Malnutrition • PEM or Protein Calorie Malnutrition • Most widespread form of malnutrition in world • Cause of 50% of infant deaths in developing countries
Marasmus • Chronic condition • Low Kcal intake • Little subcutaneous fat • Lethargic and weak • Protein tissues preserved secondary to adaptation
Marasmus • Initial treatment IV or oral glucose followed by liquids • Vitamin and mineral supplements • Solids as part of a soft diet • Limit kcal to 25 kcal/kg for 1st week • Increase to 30-35 kcal/kg
Kwashiorkor • Complex syndrome • Deficient protein in most cases • Catabolic, oxidative, or toxic stressors also to blame • More correct as syndrome of protein dysmetabolism • Edema thought to be from alteration in capacity to manage salt
Kwashiorkor • Correct protein deficiency • 2 methods in literature • Adequate protein with adequate non-protein kcal for protein sparing • High protein diet – 2.5 to 3.0 grams/kg
Excess • Increase risk of colon Cancer • High protein, Low CHO =poor bone health • Amino Acid supplements are unnecessary • eat more high protein, low fat foods • To build muscles-exercise, adequate kcal, and adequate protein
To BUILD muscles • Extra Exercise • Average Protein • Extra kcal from carbohydrates
Protein Needs • Needs Increase with • growth • start of an exercise program • Kcal restriction (dieting, anorexia) • Depleted glycogen stores
Requirements • Minimum 0.6 g/kg • Normal 0.8-1.2 g/kg • 10-20% of total Caloric intake
Protein • Found in milk, vegetables, meats, and starches • Trace amount in fruit • None in pure fat
Amino Acids • Food proteins start as polypeptides • Broken down to A2 by digestion • casein = milk and cheese • albumin = eggs • gluten = wheat • Cause of food allergies
Protein and Foods • Body Builder, 200 lbs. • ~140-180 g protein day • Marathon runner, 150 lbs. • 90-135 g protein day • Young gymnast, 80 lbs. • 72 - 80 g protein day
Protein Sources • 1 cup low fat milk or yogurt = 8 g • 1 oz. Cheese = 8 g • 2 T. Peanut Butter = 8 g • 2 large eggs = 12 g • 4 oz chicken or beef = 30 g • 1 can tuna = 40 g
Protein • Complete proteins • contain all essential • animal sources • Incomplete proteins (limiting AA) • missing some essential • plant sources • Complementary proteins • matched to provide all essential
Complementary Proteins • Black beans and rice • Peanut butter and wheat bread • Tofu and stir fried vegetables • Vegetarians usually eat enough complementary proteins over course of one day • want lots of variety
Vegetarian Diets • Vegans-only eat plant foods • Lacto-vegetarians-includes dairy • Lacto-ovovegetarians-includes dairy and eggs • Nutrients of concern • Iron and zinc • Calcium and Vitamin D • Linolenic Acid and Vitamin B12
Supplements • Hydroxicitric Acid (Ultra Burn) • Modified form of citric acid • Effectiveness not proven • Chitosan (Fat Trapper) • plant fiber plus chitosan • potential to impair absorption of fat soluble drugs
Supplements • Conjugated Linoleic Acid • Not effective • Ephedrine (Metabolife, Diet fuel) • Increase BMR, can cause stroke/chest pain/seizures • Pyruvate (Exercise in a Bottle) • Effective dose $300 per day • Study used kcal control diet/ experimental group lost 3.5 pounds more
At the Olympics • Aranesp or Epoetin • Indicated for treatment of anemia associated with chronic renal failure • Helps build red blood cells • Similar to getting a transfusion prior to an event • Not illegal yet
Caffeine • Limit: 12 mcg caffeine/ml urine • 8 Coffees • 16 Colas • 24 Anacin • 4 Vivarin Safe and effective dose: 2.5 mg caffeine/lb/bw 2-3 cups coffee as tolerated
Caffeine and Exercise • Pro: May make exercise seem easier and enhance performance • Con: May cause upset stomach, nervousness • Each person responds differently • Know YOUR BODY!
Creatine • Loading (5-7 days) = 20-25g/d • 0.3g/kg • Dose 5 g q 3-4 hours, take with food • Maintenance = one 5 g dose/ d • 0.3 g/kg • Unknown long term side effects • Caution if renal disease, cramping, GI distress
L-carnitine • Promoted to increase fatty acid oxidation • Studies have failed • Supplementation probably not necessary
Chromium • Enhances transport of glucose into the muscles; enhances insulin’s effect if chromium deficient. • No benefits seen in professional research with football players or novice body builders. • RDI: 200 mcg (cheese, mushrooms, chicken, corn, beef) • Excess can create mineral imbalances
Supplements • Recommended to the President’s Council that no NCAA member institution should supply “dietary supplements” to athletes • The dose makes the poison. • Natural is not always safe.