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Presented By: Jessica Calhoun Heather Mason Thusita Kannangara October 11, 2010 Image fromtalk.gagajoyjoy.com Americans have become obsessed with protein! In gyms, restaurants, medical offices and stores we are bombarded with ads and displays of protein supplements. Many of these beliefs about protein are incredibly exaggerated or just plain wrong. Derived from Greek “of first rank” or “primary” Found in 40% of skeletal muscle, 25% in organs and the remainder in the skin and blood Play vital roles in almost every biological process Macromolecules composed of C, H, O and N which are formed when large amounts of subunits or amino acids link together creating long chains Composed of amino acids (AA’s) Contain a central carbon atom, amino group (NH2), carboxylic group (COOH), and a side chain. Twenty AA’s, 9 essential Complete proteins contain all 9 essential AA’s Image brainandbeauty.com ALL ANIMAL SOURCES VEGETABLE SOURCES Meat Soy Poultry Tempeh Fish Grains Milk Nuts Cheese Beans Yogurt Soy/ Almond milk Starchy vegetables Requirements reflect the need to offset protein losses to maintain nitrogen homeostasis Proteins constantly being synthesized and degraded “protein turnover” Most AA’s are recycled, but a small portion are oxidized and must be replaced Protease enzymes in the stomach and small intestine (SI), break down the amino acid chains in proteins into polypeptides then further separate into individual amino acids. Absorption occurs along the SI Absorption of AA’s into the intestinal cells requires carriers; but paracellular absorption can also occur In general, BCAA absorbed faster than smaller amino acids DRI for healthy individuals: 0.8 g/kg/day Strength and endurance athletes may have increased needs Endurance athletes: 1.2 to1.4g/kg/day 9-10% daily energy Resistance athletes: 1.6 to 1.7g/kg/day 14-15% daily energy Extra protein is needed to repair damaged muscle fibers, decrease the rate of muscle protein breakdown, replenishment of depleted energy stores, and synthesis of new protein molecules 18th century: muscles primarily composed of protein 18th century: Belief that protein was the major fuel source during exercise Observations of affluent laborers diets lead to the “Voit Standard” or 118 grams of pro/day 1904: 35–50 g of protein a day was believed adequate for adults 2010: It is understood that the major energy fuel source is carbohydrates and not protein Coronary artery disease Dehydration Increased Calcium excretion Supplements – possible risk for toxicity and metabolic imbalances Strain on liver and kidneys Edema Anemia Muscle atrophy Hormone imbalance Severe cases: Marasamus & Kwashikor http://www.bio.ilstu.edu/armstrong/syllabi/cassava/cassava8.htm Branched-Chain Amino Acid Supplementation and Indicators of Muscle Damage After Endurance Exercise Greer, B. , Woodard, J. , White, J. , Arguello, E. , & Haymes, E. (2007). Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. International Journal of Sport Nutrition & Exercise Metabolism, 17(6), 595-607. Image- the-fitness-motivator.com Determine if branched-chain amino acid (BCAA) supplementation decreases indicators of muscle damage compared with a carbohydrate (CHO) beverage or a noncaloric placebo (PLAC) beverage. Image Justsupplements.com Goal is to reduce muscle damage during training BCAA may reduce the extent of muscle damage via the release of anabolic hormones or by inhibiting proteolysis Ingesting BCAA’s pre and post workout has been shown to decrease post exercise creatine kinase (CK) and lactate dehydrogenase (LDH) activities Nine untrained, healthy college men Kept detailed diet record and were encouraged to maintain the same dietary pattern Avoid eating for 3 hours before each trial Subjects assigned to 1 of 3 treatment orders Exercise at 50% V02 max for 90 min. Beverages were administered at 5 minute pre exercise and at 60 min. mark. Subjects blinded to beverage, same taste and appearance 1. BCAA beverage – isoleucine, leucine, valine (200 kcal) 2. Isocaloric CHO beverage (Gatorade) (200 kcal) 3. PLAC- noncaloric, water, artificial sweetener, lemon flavor, and salts Image agron.iastate.edu Creatine kinase (CK) Lactate dehydrogenase (LDH) Isokinetic leg extension torque Led flexion torque Muscle soreness of quads (self rating) Measurements taken before exercise and at 4, 24, and 48 hours post exercise CK activities significantly lower after the BCAA trial than in the PLAC trial at all times, only lower than the CHO at 24 h CK lower in the CHO trial than PLAC at 24 and 48 h LDH was lower in the BCAA trial at 4 H, no sig. difference between CHO and BCAA No sig. effects for leg extension torque Leg flexion torque in the BCAA trial was significantly greater than both the CHO and PLAC trials at 48 h postexercise Leg Extension torque increased, but not significantly Leg Flexion Increased significantly at 48 h Data suggests BCAA supplementation attenuates muscle damage during prolonged endurance exercise in untrained college age men Smaller changes in markers in this study than previous, isocaloric? Intensity too low? AA with coingestion of CHO may be more effective than AA alone Possible mechanism- when ingested before aerobic exercise BCAA increases concentrations of human growth hormone and helps attenuate a drop in testosterone, resulting in more anabolic environment Strengths Subjects blinded Isocaloric beverage Average athlete, not highly trained All subjects performed all three trials Separated by 8 weeks Limitations Researchers not blinded No women Small sample size Intensity too low? Only theorized mechanism Timing Protein Intake Increases Energy Expenditure 24 h after Resistance Training Hackney, K., Bruenger, A., Lemmer, J. (2010). Timing Protein Intake Increases Energy Expenditure 24 h after Resistance Training. Medicine and Science in Sports and Exercise. 42(5), 998-1003. http://tiptoptone.com/resistance_training.html To determine the effect of protein (PRO) supplementation before an acute bout of heavy resistance training (HRT) on post exercise resting energy expenditure (REE) and the non protein respiratory exchange ration (RER). Hypothesis: REE would be increased and RER would be decreased up to 48 hours after HRT in those receiving PRO compared with CHO Double-blind two trial crossover design 6 resistance trained men, 3 trained women Measure one rep max (RM) 4 day dietary journal Consumed supplement 20 mins before single bout of HRT PRO supplement- 18 g whey, 2 g CHO, 1.5 g fat CHO supplement- 19 g CHO, 1 g PRO, 1 g fat REE measured 4 consecutive days with Sensor Medics metabolic system REE elevated significantly in both CHO and PRO groups at 24 and 48 h post HRT REE in response to PRO was significantly greater compared with CHO at 24 h RER decreased significantly in both groups at 24 h compared to baseline No differences observed in total energy intake or HRT volume = sets x reps x kg lifted Reduced RER indicates there is greater reliance at fat oxidation at rest Ingesting protein before HRT may be an effective way to increase energy expenditure Increases in REE may lead to improvements in body composition Volume was not increased so did not increase strength! Strengths Men and women Double-blind Controlled diet 40 references, many within the last 10 years Limitations No control group Small sample size Could use more graphs for clearer data presentation Health, ethical, religious reasons Range of vegetarianism from semi veg. to vegan Observational studies have not detected differences in performance Short term intervention studies have had similar results Protein about 85% digestible from plant diet compared to 95% with mixed diet RDA .9 g protein/ kg BW/ day for regular human Most people surpass this amount RDA could be increased to 1.3 to 1.8 g/ kg for athlete No need for strict combination of foods Choose a variety of plant sources from all food groups and achieve adequate protein balance Vegan Soy Milk Tofu Tempeh Certain Veggie burgers Nuts Peanutbutter Beans Corn, potatoes Whole grains Image al.godsdirectcontact.org Vegetarian Vegan foods plus Milk Eggs Cheese Fish? Effect of dietary protein content during recovery from high-intensity cycling on subsequent performance and markers of stress, inflammation, and muscle damage in well-trained men Rowlands, D. S., Rossler, K., Thorp, R. M., Graham, D.F., Timmons, B. W., Stannard, S.R., Tarnopolsky, M. A. (2008). Effect of dietary protein content during recovery from high-intensity cycling on subsequent performance and markers of stress, inflammation, and muscle damage in well-trained men. Applied physiology, nutrition, and metabolism, 33(1), 39-51. http://www.treehugger.com/files/2008/09/helmet-debate-is-over.php It may be most beneficial to consume protein during immediate hours of post exercise. Exercised muscle has increased blood flow, amino acid uptake and protein synthesis Amino acid uptake from high protein meal appears to be greatest following exercise Evaluate the effect of post exercise protein consumption on next day high intensity cycling performance Investigate presence of recovery and evaluate high intensity performance after 3 days. Double-blind, randomized, crossover design 12 trained male cyclists Cyclists performed 3, 2.5 hour programmed cycling endurance exercise tests over a 4 day period in the laboratory. Day 3 was a rest day. Day 1 & 2, each cyclist consumed treatment. The protein group received 0.8 g of pro/kg/hr in form of bar or beverage. Control group consumed 0.12 g pro/kg/hr and 2.35g cho/kg/hr Instructed to consume 8 times throughout a 4 hour period. Day 1 – Cycling protocol performed. Treatment was given and blood samples taken every 30 min over 3 hour period. Day 2 – Blood samples -> cycling protocol -> treatment -> blood samples 3x in 90 minutes. Day 3 – Rest day. Rich CHO diet provided to replenish glycogen stores Day 4 – Repeat performance of day 2 Sensation perception charts for sprints and intervals on days 2 and 4 Plasma lactate, glucose, creatine kinase (CK) cortisol, interleukin-6, C Reactive Protein (CRP), tumor necrosis factor, Net nitrogen balance Overall mean sprint power in protein group was greater on day 4 and less in control group Minor increases in strength and less nausea reported in protein group on day 4 Relative to control, protein group had reduced CK before exercise on day 4 Day 1 post exercise to day 2, control had positive N balance and negative in control. Relative to control, plasma lactate was higher in control during sprints No significant differences in glucose, cortisol & Interleukin 6 High protein post exercise diet followed by a high carbohydrate diet may enhance endurance sprinting performance in subsequent performance days. http://gymaddicts.com/the-benefits-of-protein-bars/ STRENGTHS Ample background information Cycling protocol was programmed into cycle software Semi- realistic environment Thorough explanation of measurements Invites more research on recovery and performance in endurance athletes LIMITATIONS Small sample size (n=12) Low external validity 30 y/o male cyclists Cyclists complained of being full Unrealistic to consume frequent and large amounts of pro bars/beverages post exercise Invasive Possible Day 2 and Day 3 non dietary compliance Limited similar studies Minimal studies with endurance athletes and protein recovery Hoffman, J. R., Ratamess, N. A., Tranchina, C. P., Rashti, S. L., Kang, J., Faigenbaum, A. D. (2009). Effect of a proprietary protein supplement on recovery indices following resistance exercise in strength/power athletes. Amino acids, 38(3), 771-778. http://www.eshop-healthcare.com/muscle-milk-high-protein-shake-mix/ To evaluate the effect of pre and post exercise protein ingestion on recovery in resistance exercise Double-blind, randomized design. Participants were matched for strength 15 male strength/football athletes Supplement group consumed 42 grams of proprietary protein blend (“New Whey Liquid Protein”) pre and post exercise. Placebo group consumed protein free beverage Reported to a performance laboratory four different sessions (T1-T4) T1 - Athletes tested for maximum strength T2 - Treatment consumed 10 minutes prior to exercise and 15 minutes post exercise. Blood samples taken pre and post exercise Lower body resistance exercise was performed at 80% maximum strength T3 & T4 - muscle soreness rating, treatment, resistance exercise, treatment, blood samples pre and post exercise Soreness questionnaire Blood samples to measure serum testosterone, cortisol, hemoglobin and hematocrit Dietary recall Dietary recall - no difference in energy expenditure between the groups No significant difference in muscle soreness PL performed significantly fewer repetitions at T3 and T4 than they did at T2 SUP performed better than the placebo group at T3 and T4 when compared T2 PL elevated CK in T3 and T4. SUP CK remained stable Protein ingestion pre and post resistance exercise may have a greater improvement in exercise recovery in the following days STRENGTHS Ample background information Variety of references Unexpected findings were explained with other studies States that more research is needed in regards to protein timing and muscle repair LIMITATIONS Limited sample size (n=15) Low external validity – study only looked at college male resistance/football athletes Results not attributed to pre or post PRO ingestion individually One of the first studies to show significant recovery from PRO SUP pre and post exercise Dietary recall was taken 1 week prior to study Milou, B., Koopman, R., Gijsen. A., Vandereyt, H., Kies, A. K., Kuipers, H., Saris, W.H.M., VanLoon, L.J.C. (2008). Protein co-ingestion stimulates muscle protein synthesis during resistance type exercise. American Journal Physiological Endocrinal Metabolism, 5:70-77. Few studies have examined the effect of coingestion protein and carbohydrate on muscle protein synthesis during exercise. The results of these studies show that the stimulation effects of CHO + Protein on body protein synthesis during endurance and resistance type exercise Assess the effect of protein and carbohydrate supplementation on synthesis of muscle protein and whole body protein balance during resistance exercise at fed state. • • • • • • • Ten healthy male volunteers All subjects participated in two screening sessions Body composition –using hydrostatic weighing Leg volume Maximal oxygen uptake capacity One repetition maximum – for two legs Work load capacity All subjects received a standardized diet of 54.3 ±1.8 kJ/kg body weight, consisting of 62% Carbohydrate, 22% Fat, and 16% Protein evening before each experimental day. • During experimental day 0.16±0.01MJ.kg body wt 1.day-1, consisting of 62% carbohydrate, 13% Protein, and 26% Fat. • Subjects ingested 78±g protein via standardized diet and additional 21±1 g from CHO+ Protein treatment • Each subject participated in two treatments separated by two weeks • During 2hr resistance type exercise either carbohydrate or Carbohydrate +protein treatment received • Subjects received a dose of 0.15g.kg-1.h-1 carbohydrate (50% glucose and50%maltodextrin), with or without 0.15g.kg-1.h-1 protein hydrolysate beverage (1.5ml/kg)every 15 mins during exercise • Arterialized blood samples and muscle biopsies were taken every 15 min( t=0 and t=120) • Whole body net protein balance positive in CHO +Protein treatment CHO treatment achieved negative net protein balance Whole body protein breakdown rates lower in CHO+ Protein experiment Mixed muscle protein synthesis rates higher in the CHO+ PRO treatment Protein co-ingestion with carbohydrate improves whole body protein balance and increases mixed muscle protein synthesis rate during resistance type exercise STRENGTHS LIMITATIONS Same group of participants used in both experiments (act as own control) Athletes performed in a fed state Recent reference articles (after 2000) Small sample size (n=10) They were not elite or trained athletes Do not participate in any regular sports activities. When counseling athletes in regards to protein needs and exercise, it is important to understand the athletes needs and goals to help them perform optimally. A tool that dietitians can be use when counseling athletes in regards to protein needs and exercise. Connected through 4 Levels Macrosystem: wider society, culture, media and Ex. Athletes are susceptible to media and advertisements of high protein diets, supplement use and are often intrigued by such items that claim to performance. Mesosystem: school policies, trainers and coaches Ecosystem: family values, norms and expectations Macrosystem: personal beliefs, values and skills http://gozips.uakron.edu/~susan8/devparch/urie.jpg In regards to protein and exercise, dietitians are often called on to design athletic diets Understand the sport, physical requirements, time dedication, living situation, cultural needs, age, goals and education level Recommendations can be made based of the athlete’s everyday influences Increased communication and understanding between the athlete and dietitian Lead to improved athletic performance "Mix one part fact with several parts ignorance; season with advertising, sprinkle on a need for that all-important competitive edge, and you have a recipe for protein supplements" (Caffery, 2010) http://rawfoodsos.com/2010/02/16/the-greatprotein-debate-part-2/ Protein ingestion before exercise has been shown effective in decreasing muscle soreness and improving repetition performance in resistance trained athletes Protein has shown to improve mean sprint performance in well trained endurance cyclists Supplementation is overused in college athletes and has not proved to be more effective than dietary protein Further research is needed to determine the optimal amount and timing of protein needed for sports Berardi, N.J., Price, T. B., Noreen, E. E., Lemon, P. W. R. (2006) Post exercise muscle glycogen recovery enhanced with a carbohydrate- protein supplement. Medicine and science in sports and exercise, 38:6, 1106-1113. Berning, J. R., & Steen, S. N. (1998). Nutrition for sport & exercise (2nd Ed.). Gaithersburg, MD: Aspen Publishers, Inc. Biolo, G., Tipton, K.D., Klein, S., Wolfe, R.R. (1997). An abundant supply of amino acids enhances the metabolic effects of exercise on muscle protein. American Journal of Physiology, 273:122- 129. Biolo, G., Maggi, S. P., Williams, B. D., Tipton, K. D., Wolfe, R.R. (1995) Increased rates of muscle protein turnover and amino acid transport after resistance exercise in humans. American Journal of Physiology. 268: 514–520. Butterfield, G.E. (1987). Whole body protein utilization in humans. Medicine and science in sports and exercise, 19:157-165. Chelsy, A., MacDougall J. D., Tarnapolsky, M. A., Atkinson, S. A., Smith, K. (1992). Changes in human muscle protein synthesis after resistance exercise. Journal of Applied Physiology, 73:1383-1388. Feldman, R. S. (2008). Development across the life span (5th ed.). New Jersey: Pearson Prentice Hall Gropper, S.S., Smith, J.L., Groff, J.L. (2009). Advanced nutrition and human metabolism (5th Ed.). Belmont, CA: Wadsworth Publishing. Greer, B., Woodard, J., White, J., Arguello, E., & Haymes, E. (2007). Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. International Journal of Sport Nutrition & Exercise Metabolism, 17(6), 595-607. Hackney, K., Bruenger, A., Lemmer, J. (2010). Timing Protein Intake Increases Energy Expenditure 24 h after Resistance Training. Medicine and Science in Sports and Exercise. 42(5), 998-1003. Ivy, J. I., Ding, Z., Cialdella-Kam, L. C., Morrison, P. J. (2008). Post exercise carbohydrate – protein supplementation: phosphorylation of muscle proteins involved in glycogen synthesis and protein translation. Amino Acids, 35:89-97. Ivy, J. L., Goforth J. H., Damon, B. M., MacCauly, T. R., Parson, E.C., Price, T. B. (2002). Early post exercise muscle glycogen recovery is enhanced with a carbohydrate- Protein supplement. Journal of Applied Physiology, 93:1337-1344. MacDougall, J. D., Gibala, M. J., Tarnapolsky, M. A., Macdonald, J. R., Interisano, S.A., Yarasheski, K. E. (1995). The time course for elevated muscle protein synthesis following heavy resistance exercise. Canadian Journal of Applied Physiology, 20:480-486. Mahan, L. M., Escott-Stump, S. (2008). Krause’s food & nutrition therapy (12th Ed.). St. Louis, MO: Saunders Elsevier. Maughan, R. J., Burke, L. M., Coyle, E. F. (2004). Food, nutrition and sports performance II. New York, NY: Routledge. McDougall, J. (2010). A Brief History of Protein: Passion, Social Bigotry, Rats, and Enlightenment. Retrieved October 5, 2010, from http://www.all-creatures.org/health/abrief-hi.html Milou, B., Koopman, R., Gijsen. A., Vandereyt, H., Kies, A. K., Kuipers, H., Saris, W.H.M., VanLoon, L.J.C. (2008). Protein coingestion stimulates muscle protein synthesis during resistance type exercise. American Journal Physiological Endocrinal Metabolism, 5:70-77. Phillips, S. M., Tipton, K. D., Aarsland, A., Wolf, S. E., Wolfe, R. R. (1997). Mixed muscle protein synthesis and breakdown after resistance exercise in humans. American Journal of Physiology, 273: 99–107. Sizer, F., & Whitney, E. (2006). Nutrition concepts and controversies (10th Ed.). Belmont, CA: Thompson Wadsworth. Tang, J. E., Perco, J. G., Moore, D. R., Wilkinson, S. B., Phillips, S. M. (2007). Resistance training alters the response of fed state mixed muscle protein synthesis in young men. 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