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Research & UpdatesBCAA SUPPLEMENTATION REDUCES MUSCLE DAMAGE RESPONSES TO EXERCISEResistance exercise causes mechanical damage from shear stress to the muscle cells during exercise, as well as a complex biochemical damage that occurs for several hours to days after exercise. Supplements that reduce the amount of muscle disruption after a bout of exercise have the potential to speed recovery in between exercise bouts and thereby allow for more intense training sessions. The branched-chain amino acids (BCAA: leucine, isoleucine, and valine) have been shown in prior work to be very important for promoting protein synthesis and a positive nitrogen balance, but their effect on reducing exercise-induced muscle damage is less clear. A recent study tested the effect of BCAA versus a carbohydrate beverage on muscle damage markers after cycling exercise in untrained young men. The beverages each contained 200 kcal and were consumed before and at 60 min of exercise. Blood markers of damage and performance were assessed before and immediately after, 4 hr, 24 hr, and 48 hr after exercise. The BCAA beverage resulted in less accumulation of multiple markers of muscle damage in the blood and reduced muscle soreness in subjects 24 hr after exercise. As a result, muscle performance was higher 2 days after exercise during the BCAA trial. The results provide evidence for a novel effect of BCAA on reducing the magnitude of muscle damage after exercise and speeding recovery. Greer BK, Woodard JL, White JP, Arguello EM, Haymes EM. Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. Int J Sport Nutr Exerc Metab. 2007 Dec;17(6):595-607. GREEN TEA BOOSTS IMMUNE FUNCTION AND PREVENTS COLD AND FLU SYMPTOMS In addition to maki ng you feel miserable, being sick with the cold and flu can stifle your progress in the gym. Researchers reported in a recent manuscript that there is yet another reason to consume green tea. They randomized subjects into a group who received capsules containing a proprietary mixture of EGCG and theanine or a placebo group. The researchers followed them for 3 months and documented their cold and flu symptoms as well as assessing their immune function. Almost one-third fewer subjects reported having cold and flu symptoms in the green tea group. There was also a decrease in the number of days subjects had symptoms and the total number of days they needed medical treatment. The authors suggested these effects may have been due to enhanced immune function because green tea was shown to have a positive effect on immune cells. These results could have very important implications on preventing cold and flu symptoms and therefore keeping people healthy by improving their innate immune response. Rowe CA, Nantz MP, Bukowski JF, Percival SS. Specific formulation of Camellia sinensis prevents cold and flu symptoms and enhances gamma,delta T cell function: a randomized, double-blind, placebo-controlled study. J Am Coll Nutr. 2007 Oct;26(5):445-52. PRIOR SUPPLEMENTATION WITH CoQ10 SIGNIFICANTLY REDUCES EXERCISE-INDUCED OXIDATIVE STRESS AND MUSCLE DAMAGE Exercise is associated with increased oxidative stress that, if not countered, can cause suboptimal adaptations to training. One supplement that has the potential to minimize oxidative stress is CoQ10. CoQ10 functions in the mitochondria, the “powerhouses” of the cell to assist in making energy (ATP) from carbohydrates and fats. CoQ10 primarily acts as an antioxidant and is involved in the synthesis of energy (ATP), but also has other important functions inside the mitochondria such as stabilizing membranes. Because of CoQ10’s role in oxidative stress, energy production, and stabilization, it is useful in preventing damage to muscle during periods of stress. In fact, CoQ10 has been used in prevention and treatment of cardiovascular disease in heart patients for decades, but its role in preventing exercise-induced stress has not been examined. Japanese researchers studied the effects of CoQ10 supplementation in elite Japanese kendo athletes. The subjects were assigned to either take 300 mg CoQ10/day or placebo for 20 days. The subjects were training intensely an average of 5.5 h per day for 6 days per week. Blood analyses indicated that the CoQ10 group had lower levels of lipid peroxides indicating significantly lower oxidative stress. CoQ10 supplementation also resulted in lower concentrations of two markers of muscle membrane damage, creatine kinase activity and myoglobin, compared to the placebo group. These are promising results showing the potential value of CoQ10 supplementation in reducing exercise-induced oxidative stress and muscle damage. Kon M, Tanabe K, Akimoto T, Kimura F, Tanimura Y, Shimizu K, Okamoto T, Kono I. Reducing exercise-induced muscular injury in kendo athletes with supplementation of coenzyme Q10. Br J Nutr. 2008 Feb 20;:1-7 [Epub ahead of print] SUPPLEMENTATION WITH PROTEIN-CARBOHYDRATE-CREATINE FORMULA DURING TRAINING AUGMENTS MUSCLE SIZE AND STRENGTH GAINS Both creatine and protein supplementation have each been shown in prior studies to augment adaptations to resistance training. It remains unclear however if the combination of these two scientifically validated supplementation strategies would be additive. Australian researchers tested this idea in three groups of resistance-trained men who all performed a 10-week resistance-training program. One group received protein only (~103 g whey isolate per day). Another group received a combination of protein and carbohydrate (~52 g whey isolate and ~59 g glucose per day). A third group received a combination of protein, carbohydrate and creatine (~48 g whey isolate, ~53 g glucose, and 8.4 g creatine monohydrate per day). Supplements were consumed 3 times per day. Increases in lean body mass in the protein and protein-carbohydrate supplement groups were similar (~10 pounds), whereas the protein-carbohydrate-creatine group increased lean body mass by an average of more than 15 pounds. Muscle biopsy samples were taken from the leg and showed that there was also a greater increase in the size of muscle fibers in the protein-carbohydrate-creatine group, as well as greater increases in maximal strength. These results are novel and important, showing that the combination of protein and creatine promotes the optimal anabolic environment to support muscle growth and strength. Cribb PJ, Williams AD, Hayes A. A creatine-protein-carbohydrate supplement enhances responses to resistance training. Med Sci Sports Exerc. 2007 Nov;39(11):1960-8. Landmark Clinical Test Documents Remarkable 26% to 32% Strength Increases Once again, we’ve got to hand it to the tireless innovators at BioQuest. While lesser manufacturers throw up scientific "smoke screens" around their products, BioQuest never misses a chance to seek out new opportunities to independently and clinically validate their own formulations. A recent clinical trial conducted by Douglas Kalman PhD, RD on healthy active males who participated in an exercise and nutrition program that featured Myozene, revealed bodybuilding results that were truly impressive. When MyoZene was consumed 45 minutes after completing the prescribed weight-lifting regimen (one that met the guidelines for hypertrophy training from the American College of Sports Medicine), participants experienced strength and muscular endurance gains of up to 32%, in addition to gains in lean muscle mass. This is most impressive considering creatine ingestion or protein alone result in considerably less strength, muscle, and endurance gains. Within the test’s time frame (one month), the MyoZene-receiving subject group gained 26% to 32% strength/muscular endurance. The MyoZene-drinking subjects (ingesting one serving within 45 minutes of finishing the exercise session) also gained approximately 2.2 pounds of lean muscle within the month, while reducing some fat too. Needless to say, this is an electrifying result. Recently, a significant number of "ultra-rapid-action" hydrolyzed protein products have begun appearing on the market, hoping to ride the wave of enormous positive feedback generated by MyoZene’s breakthrough technology two years ago. Most of these products come with elaborate marketing claims and no clinical data to back them up. It’s refreshing to see that one manufacturer, BioQuest, is stubbornly keeping to the ethical and scientific high road while others merely try to capitalize on others’ successes. With clinical results like these, it’s no wonder MyoZene has become the preferred mass building choice by elite bodybuilders nationwide. 2007. Myo-2007 clinical trial, Miami Research Associates. Miami, Florida. Aspire-IRB, San Diego, CA. Data on File. Creatine-Whey Hydrolysate-Carbohydrate Supplementation By Anssi Manninen A recent study at the Victoria University in Australia examined the effects of a creatine monohydrate-whey protein hydrolysate-carbohydrate supplement in comparison with a supplement containing a similar amount of nitrogen (protein) and energy during resistance training. In a double-blind, randomized protocol, male gym rats were matched for strength and placed into one of three groups: 1) whey protein hydrolysate, 2) whey protein hydrolysate + carbohydrate, or 3) the same whey protein hydrolysate plus carbohydrate supplement (1.5 grams per kilogram of body weight per day) enriched with creatine monohydrate (0.1 grams per kilogram of body weight per day). Assessments were completed the week before and after a 10-wk structured, supervised resistance exercise program. The results revealed that a a creatine monohydrate-whey protein hydrolysate-carbohydrate supplement provided the greatest improvements in muscle strength and lean body mass. According to the authors, at least 40% of the strength improvements could be attributed to hypertrophy of muscle involved in this exercise. The take-home message is that one should ingest a mixture of creatine monohydrate, whey protein hydrolysate and carbohydrate (e.g., MyoZene) both before and after resistance training to maximize the anabolic effects of exercise. Cribb PJ et al. A creatine-protein-carbohydrate supplement enhances responses to resistance training. Med Sci Sports Exerc. 2007 Nov;39(11):1960-8. EGCG, THE BIOACTIVE IN GREEN TEA, PROMOTES FAT OXIDATION Green tea has been an exciting supplement to watch unfold as more research continues to support its use in promoting health. Several studies have shown improvements in fat loss with regular use of green tea. The mechanism by which green tea works to shed body fat is complex and probably multi-factorial. However, one probable mode of action is on fat oxidation. The latest study from German researchers tested the effects of epigallocatechin gallate (EGCG), the most abundant catechin in green tea, on carbohydrate and fat metabolism. Carbohydrate and fat oxidation rates was measured after the ingestion of 300 mg of EGCG or placebo in the fasted state and after a standard meal. Compared to placebo, supplementation with EGCG caused a shift in energy utilization from carbohydrate to fat oxidation. The effect was more pronounced after ingestion of the meal. In the placebo trial only 30% of the total energy burned after the meal was attributed to fat, whereas 54% of the energy burned came from fat oxidation after EGCG supplementation. These results show acute supplementation with 300 mg EGCG encourages use of fat over carbohydrate as fuel, which provides a plausible mechanism t explain the anti-obesity effects of green tea. Boschmann M, Thielecke F. The effects of epigallocatechin-3-gallate on thermogenesis and fat oxidation in obese men: a pilot study. J Am Coll Nutr. 2007 Aug;26(4):389S-395S. SHORT-TERM CREATINE SUPPLEMENTATION ENHANCES MUSCLE PERFORMANCE AND ACTIVITIES OF DAILY LIVING IN OLDER WOMEN Muscle mass and strength peak between the ages of 20 and 35 years and steadily decline thereafter until the sixth decade of life where a sharp decline occurs. This loss in muscle mass and function adversely affects normal activities of daily living, like getting up from a chair, for many older people. Recent studies provide a strong case for creatine supplementation in offsetting these effects of aging. After just 7 days of creatine supplementation (20 g per day divided in 3 equal doses) or placebo, women between the ages of 58 and 71 years showed a remarkable improvement in several measures of muscular performance. Creatine supplementation led to significant increases in maximal bench press and leg press strength, upper and lower body power, and two functional performance tasks encountered during everyday life – a sit and stand test and a tandem gait test. These improvements in functional performance occurred despite no physical training during the 7 day period and no side effects were reported, highlighting the simple yet effective use of creatine to enhance physical performance in older individuals. Gotshalk LA, Kraemer WJ, Mendonca MA, Vingren JL, Kenny AM, Spiering BA, Hatfield DL, Fragala MS, Volek JS. Creatine supplementation improves muscular performance in older women. Eur J Appl Physiol. 2007 Oct 18; [Epub ahead of print] LONG-TERM CREATINE SUPPLEMENTATION ENHANCES MUSCLE GAIN AND FAT LOSS IN OLDER ADULTS The ability of creatine supplementation to promote healthy aging is even more dramatic when combined with resistance training. Canadian researchers had older men and women (>65 years) perform a supervised resistance training program (2 days/week) for 6 months while supplementing with either placebo or creatine + conjugated linoleic acid (CLA). The reason for including CLA was to potentiate improvements in body composition since creatine increases in fat-free mass and CLA targets fat loss. After 6 months, the creatine+CLA group had a two-fold greater increase in fat-free mass (4.6 pounds) compared to placebo (2.0 pounds). Fat mass was also reduced more in the creatine+CLA group (4.2 pounds) compared to placebo (-0.9 pounds). The greater muscle gains translated into improved functional performance in the creatine+CLA group. Creatine combined with resitance training and CLA is a potent formula for enhancing body composition in older adults. Tarnopolsky M, Zimmer A, Paikin J, Safdar A, Aboud A, Pearce E, Roy B, Doherty T. Creatine monohydrate and conjugated linoleic Acid improve strength and body composition following resistance exercise in older adults. PLoS ONE. 2007 Oct 3;2(10):e991. CREATINE HELPS TURN BACK THE CLOCK Two recent studies in older adults, one short-term (7 days) and one long-term (6 months), clearly showed the power of creatine to enhance muscle gain and fat loss, and improve several measures of functional performance including activities of daily living. These studies in humans are also supported by animal work. Using an animal model of aging, it was shown that creatine supplementation extended maximum life span by 3.5%. Even more impressive was the effect of creatine supplementation on “healthy” life span (defined as the age before animals were classified as suffering from disease) which significantly increased by 9%. Bender A, Beckers J, Schneider I, Hölter SM, Haack T, Ruthsatz T, Vogt-Weisenhorn DM, Becker L, Genius J, Rujescu D, Irmler M, Mijalski T, Mader M, Quintanilla-Martinez L, Fuchs H, Gailus-Durner V, de Angelis MH, Wurst W, Schmidt J, Klopstock T. Creatine improves health and survival of mice. Neurobiol Aging. 2007 Apr 6; [Epub ahead of print] CLA BURNS FAT WHILE YOU SLEEP To lose body fat without changing diet, you have to increase the number of calories burned. The typical approach is to recommend exercise as a means to increase energy expenditure. But we burn calories all day long. So it is also possible that increasing energy expenditure at other times could result in greater fat loss. A number of studies have suggested CLA supplementation is associated with greater fat loss. A recent study tested whether CLA could affect resting energy expenditure and fat burning during sleep. Subjects in this study were provided either a placebo or CLA (3.2 g/day) for 6 months. Before and after supplementation, subjects were studied in an enclosed room that allowed very sensitive measurement of the total calories and fat calories they burned during a 24 hour period. The results showed that total energy expended while sleeping was 43 kcal more in the CLA group compared to placebo. The CLA group also burned 99 more kcal of fat while sleeping than placebo. These results indicate that CLA reduces body fat by increasing energy expenditure and fat oxidation during sleep. Close RN, Schoeller DA, Watras AC, Nora EH. Conjugated linoleic acid supplementation alters the 6-mo change in fat oxidation during sleep. Am J Clin Nutr. 2007 Sep;86(3):797-804. CREATINE BOOSTS BRAIN POWER There is overwhelming evidence that creatine supplementation helps build bigger muscles. The mechanism probably involves improved energy status because creatine accumulates in muscles and provides a very critical source of ATP. A new line of research has investigated possible benefits of creatine in other tissues. One area that has sparked interest is the brain. Creatine is an important source of energy for cells in the brain that have high metabolic needs required for processes like working and long-term memory. Prior work using magnetic resonance spectroscopy has shown that creatine supplementation results in significant increases in creatine levels in the human brain. Following up on this work, British researchers supplemented older adults with placebo or creatine for one week. Subjects completed a battery of cognitive tests that assessed verbal and spatial short- and long-term memory. Creatine supplementation enhanced several of the tests including forward number recall, forward and backward spatial recall, and long-term memory. These findings add to a line of research indicating that creatine supplementation improves cognitive functioning. Creatine supplementation appears to enhance both muscle and brain power. McMorris T, Mielcarz G, Harris RC, Swain JP, Howard A. Creatine supplementation and cognitive performance in elderly individuals. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2007 Sep;14(5):517-28. WORLD EXPERTS MEET ON PROTEIN SUPPLEMENTS FOR ATHLETES Protein has received more attention among strength and power athletes than any other nutrient. There has also been considerable research targeted at better understanding the optimal use of protein to enhance muscle size, strength, and performance. Given the emerging science of protein supplementation, researchers in the field felt compelled to meet to discuss the state of the art in the application of protein, protein hydrolysates, and amino acids in sports nutrition. Top protein researchers from around the world met last May for two days to review the research and share their opinions on protein supplementation. Here are some of the major outcomes of the conference. 1. Development of designer protein hydrolysates where the peptides are manipulated to increase bioactivity to target endpoints such as protein synthesis is a promising area. 2. Essential amino acids, branched-chain amino acids, and leucine are critical in activating intracellular signaling pathways that control the anabolic response to resistance exercise. 3) The optimal amount of protein for athletes is higher than the RDA and in the range of 1.2 to 1.6 grams protein per kilogram body weight. 4) Maximal increases in protein synthesis are achieved with a dose of 20-25 grams of high quality protein. 5) Providing a high quality source of protein is critical both before and after exercise. Overall, the group identified several areas in need of further research, but agreed the evidence to date is strong supporting the need for high quality sources of protein consumed at specific times to bring about maximal adaptations to exercise training. Protein and protein hydrolysates in sports nutrition: proceedings of a workshop held in New Orleans May 28-29, 2007. International Journal of Sports Nutrition and Exercise Metabolism. 17:supplement, 2007. COMBINATION NUTRITION FORMULA AUGMENTS THE ANABOLIC RESPONSE TO RESISTANCE EXERCISE Optimizing the anabolic response to resistance exercise is critical to get the most benefit from a workout. Few supplements in isolation can significantly alter the exercise-induced responses in anabolic hormones like testosterone, growth hormone, and insulin. If the right nutrients were combined, there is a greater chance anabolic hormones and recovery responses from resistance exercise could be enhanced. Investigators tested this hypothesis in a group of resistance trained men. On two occasions the subjects performed a heavy resistance exercise bout 30 min after after consuming a either a placebo or a multi-nutrient formulation. The formula consisted of a wide range of vitamins, minerals, and other bioactive nutrients. Notable were the presence of creatine (3 g), arginine alpha ketoglutarate (2 g), green tea extract (500 mg), carnitine (400 mg), and ribose (1.5 g). Performance during the resistance exercise bout was significantly enhanced by the nutrient formula. The formula also potentiated the anabolic hormone response as shown by increased levels of testosterone, growth hormone and insulin like growth factor-I. Finally, the nutrient formula also decreased markers of muscle damage (creatine kinase and myoglobin) indicating less muscle tissue damage. These results support the concept of combining nutrients to obtain maximal endocrine responses to exercise and for promoting recovery. Kraemer WJ, Hatfield DL, Spiering BA, Vingren JL, Fragala MS, Ho JY, Volek JS, Anderson JM, Maresh CM. Effects of a multi-nutrient supplement on exercise performance and hormonal responses to resistance exercise. Eur J Appl Physiol. 2007 Aug 16; [Epub ahead of print] GLUCOMANNAN PLUS EXERCISE IMPROVES BODY COMPOSITION AND LIPIDS Glucomannan is a unique type of fiber that has been shown to induce several positive effects. One of the main benefits of glucomannan over other fibers is that it has a much greater viscosity or ability to hold water. The health promoting effects of fibers are primarily attributed to this characteristic. Thus, smaller doses of glucomannan can be used to achieve dramatic effects. While a number of studies have documented the ability of glucomannan to enhance weight loss and improve risk for diabetes and heart disease, no previous studies had examined the additive effect of glucomannan and exercise training. A paper just released examined the combined effects of glucomannan and training in overweight men and women. The participants supplemented their normal diets with 3 g of glucomannan (1500 mg two times per day before a meal). One group also performed a structured 8 week exercise program that included both resistance and endurance training. In men, glucomannan alone decreased the percentage body fat by 1.4% (35.6 to 34.2%), but the addition of exercise resulted in a 2.9% decrease in percent body fat (36.8 to 33.9%). A similar pattern occurred in women with glucomannan alone decreasing percent body fat by 1.9%, and glucomannan plus exercise decreased body fat by 2.8%. Glucomannan also resulted in a decrease in blood cholesterol levels, and the exercise group also boosted HDL cholesterol. The findings provide further support for the health promoting effects of glucomannan in small doses taken daily. The study also shows that glucomannan plus a total body exercise program results in the most favorable body composition and cholesterol responses. Kraemer WJ, Vingren JL, Silvestre R, Spiering BA, Hatfield DL, Ho JY, Fragala MS, Maresh CM, Volek JS. Effect of adding exercise to a diet containing glucomannan. Metabolism. 2007 Aug;56(8):1149-58. Leucine – Not just a muscle builder By Anssi Manninen, M.H.S. Leucine is a real superstar of amino acids. It not just boosts muscle anabolism but it also prevents body fat accumulation. In a recent study at Columbia University, the investigators doubled the intake of leucine (via leucine enriched drinking water) in mice with free access to either a standard rodent chow or a high-fat diet. While the higher leucine intake didnt produce major benefits in chow-fed mice, it resulted in up to 32% reduction of weight gain and a whopping 25% decrease in body fat mass in high fat diet-fed mice. These results indicate that leucine is not a fat burner per se; rather, it prevents body fat accmulation during overeating (A high-fat diet almost always leads to significant overeating in mice). The results of this study also demonstrated that the reduction of extra lardness resulted from increased metabolic rate, while food intake wasnt decreased. But that wasnt all. Leucine supplementation also improved blood lipids and insulin sensitivity. Interestingly, the reductions in total cholesterol and "bad cholesterol" (LDL) were largely independent of leucine-induced changes in body fat mass, suggesting that high leucine intake per se improves cholesterol levels. The take-home message is that leucine-rich supplements (e.g., BioQuest MyoZene, ProSource Mega BCAA) are highly beneficial for those who wish to “bulk”, while minimizing body fat accumulation. Zhang Y et al. Increasing dietary leucine intake reduces diet-induced obesity and improves glucose and cholesterol metabolism in mice via multimechanisms. Diabetes. 2007 Jun;56(6):1647-54. Epub 2007 Mar 14. Buffered Creatine: Waste of Money? The makers of Krealkalyn® (a “buffered creatine”) claim that their product is 100% stable in stomach acid and does not convert to creatinine. They also claim, without any evidence, that creatine monohydrate is highly pH labile with more than 90% of the creatine converting to creatinine in stomach acids. A recent study by Drs. Tallon and Child examined whether Krealkalyn® supplementation reduces the rate of creatine conversion to creatinine, relative to creatine monohydrate. The creatine products were incubated in 900 milliliter of pH 1 hydrochloric acid (HCL) at 37 ± 1º C (HCL is a strong acid and the major component of stomach acid). Samples where drawn at 5, 30 and 120 minutes and immediately analyzed for creatine and creatinine. What happened? Well, the rate of creatinine formation from creatine monohydrate was found to be less than 1% of the initial dose, indicating that CM is extremely pH stable. Furthermore, this study also showed that Krealkalyn® supplementation actually resulted in 35% greater conversion of creatine to creatinine than creatine monohydate. In sum, creatine monohydrate appears to be superior to Krealkalyn®. A proven way to improve the transport of creatine into muscle cells is to spike blood insulin levels. Thats exactly what BioQuest MyoZene does. A scientifically engineered mixture of pharmaceutical grade whey protein hydrolysate and massive doses of added key amino acids (e.g., leucine) rapidly increase blood amino acid and insulin levels, leading to greatly increased uptake of both amino acids and creatine. So, it is recommended that you ingest a serving of MyoZene immediately after each resistance training session. You simply cannot find a better post-exercise supplement on this planet. Case closed. Tallon MJ, Child R. Kre-alkalyn® supplementation has no beneficial effect on creatine-to-creatinine conversion rates. ISSN Conference Abstract, 2007. CASEIN HYDROLYSATE SIGNALS PROTEIN SYNTHESIS AFTER EXERCISE In order to turn on muscle protein synthesis, a series of signals must be induced inside the muscle. Simply contracting muscle activates this cellular signaling, but nutrition has an important regulatory role as well. In particular, the signaling pathway that activates mTOR has received a lot of interest in the scientific community because the muscle requires mTOR signaling to increase protein synthesis and subsequently grow. When stimulated, mTOR activates other targets such as 70-kDa ribosomal protein S6 kinase, also called S6K1. This cascade ultimately results in increased translation of mRNAs encoding proteins. Researchers from the Netherlands asked the question: what happens to these critical signaling proteins in muscle when carbohydrate alone or carbohydrate and protein together are provided around a bout of resistance exercise. Before, immediately after, and 1 h after a single bout of resistance exercise, subjects consumed 0.3 gram per kilogram of carbohydrate or the same amount of carbohydrate with an equal amount of protein. The source of protein was a casein hydrolysate. Muscle samples were obtained before and after exercise to assess the level of activation of S6K1 in muscle. These investigators found that during recovery S6K1 was significantly higher when protein was provided with carbohydrate. The study provides a better understanding of how adding protein – in this case a casein hydrolysate - augments the signaling in muscle that turns on protein synthesis and promotes anabolism. Koopman R, Pennings B, Zorenc AH, van Loon LJ. Protein Ingestion Further Augments S6K1 Phosphorylation in Skeletal Muscle Following Resistance Type Exercise in Males. J. Nutr. 2007 Aug;137(8):1880-6. LEUCINE DRIVES PROTEIN SYNTHESIS It is probably not news that simply consuming protein induces an increase in muscle protein synthesis, which is why protein supplements are popular to consume after exercise. Researchers have begun to refine their knowledge on what it is about protein that stimulates anabolism in muscle. For example, scientists have shown that it is the level of amino acids in the blood that directly boosts protein synthesis in muscles. Specifically it is the amino acid leucine that is most highly related to protein synthesis. In a series of elegant experiments, researchers directly examined muscle protein synthesis after feeding animals various formulations of amino acids and compared them to glucose ingestion. When a complete protein was consumed (one that contains all the amino acids), protein synthesis was increased. When just essential amino acids were provided and the nonessential ones left out, the same increase was noted indicating nonessential amino acids are not required to stimulate protein synthesis. When just the BCAA were given, again there was the same increase in protein synthesis. Finally when just leucine was consumed, yet again protein synthesis increased to the same magnitude. These findings provided strong evidence that leucine was the driving force behind the ability of dietary protein to stimulate protein synthesis. Cutting edge work in the last few years has revealed how leucine directly activates a critical compound in muscle cells called the mammalian target of rapamycin (mTOR). It turns out mTOR is like a molecular switch that turns on the protein synthetic machinery in muscle and leucine is one of the major activators of mTOR. Thus, leucine not only provides the building blocks for protein synthesis, it also has a critical role in up-regulating the process. The application of all this work is that adding additional leucine to typical protein beverages is an effective strategy to maximize muscle anabolism after resistance exercise. Garlick PJ, Grant I. Amino acid infusion increases the sensitivity of muscle protein synthesis in vivo to insulin. Effect of branched-chain amino acids. Biochem. J. 1988 Sep 1;254(2):579-84.
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