Training Tip of the Week MILK: It does the body builder good! Believe it or not, milk has a great combination of the right nutrients that helps an athlete recover after a heavy competition or work-out. Milk has the recommended 3:2 ratio of carbohydrate to protein needed to both replenish energy stores and build muscle. Studies show that drinking about 2 cups of skim milk for the average sized person within 1 hour of weightlifting will help build about 60% more muscle than if water or a commercial sports drink is consumed. For the more endurance athlete, research shows that consuming the same amount of milk after vigorous exercise improves recovery and allows the athlete to exert more energy for a longer period of time before exhaustion. Nutrient Recommendations Within 1 Hour of Exercise: - Protein 0.1g/kg - Carbohydrate 0.15g/kg "Strength training causes muscle cells to be extremely sensitive to insulin," Evans said in an e-mail interview. "Insulin stimulates muscle protein synthesis by increasing the transport of amino acids into the cells." But the "window of opportunity" for this synthesis is short-lived. "The protein should be consumed before, during, or within 30 minutes of completion of the exercise," he said. And the protein should be of "high quality" - that is, it should contain all of the essential amino acids like whey, casein (a milk protein), or meat; in general, you should consume about 15 grams of protein along with 20 grams of sugar. Eating extra protein is less important for people doing aerobic exercise; after an aerobic workout, the most important thing is to replace carbohydrates, to restore energy used during the workout, Evans said. "For most people, a mixed meal of protein and carbohydrates is sufficient," said Miriam Nelson, an associate professor of nutrition and physical activity at the Friedman School of Nutrition at Tufts University. "But for elite athletes, where microdifferences make a difference, extra protein is important." The simplest thing to remember, she said, is that, for most people, "you want to have a snack or small meal that's rich in carbohydrates and protein within about 20 to 30 minutes of your workout."
Chocolate Milk May Improve Recovery After Exercise Chocolate milk is an effective postexercise drink that improves recovery, according to the results of a small, randomized trial reported in the February issue of the International Journal of Sport Nutrition and Exercise Metabolism. "Our study indicates that chocolate milk is a strong alternative to other commercial sports drinks in helping athletes recover from strenuous, energydepleting exercise," coauthor Joel M. Stager, PhD, from Indiana University in Bloomington, said in a news release. "Chocolate milk contains an optimal carbohydrate to protein ratio, which is critical for helping refuel tired muscles after strenuous exercise and can enable athletes to exercise at a high intensity during subsequent workouts." On 3 separate days, 9 male, endurance-trained cyclists performed an interval workout followed by 4 hours of recovery, and a subsequent endurance trial to exhaustion at 70% maximum oxygen consumption (VO 2max ). In a single-blind, randomized design, the men drank equivalent volumes of chocolate milk, fluid replacement drink (FR), or carbohydrate replacement drink (CR) immediately after the first exercise bout and 2 hours of recovery. The chocolate milk and CR had equivalent carbohydrate content. Primary endpoints were time to exhaustion, average heart rate, rating of perceived exertion, and total work for the endurance exercise. "The results of this study suggest that chocolate milk, with its high carbohydrate and protein content, may be considered an effective alternative to commercial FR and CR for recovery from exhausting, glycogen-depleting exercise," the authors write. Int J Sport Nutr Exerc Metab. 2006;16:78-91 Milk: The Best Muscle-Builder? Milk Helps Build More Muscle After Exercise Than Soy, Carb Drinks, Researchers Say Drink milk after your weight training workouts, and you may gain more muscle and lose more body fat than if you drink a soy or carbohydrate drink, according to the results of a new study. Researchers compared the effects of drinking nonfat milk, a soy protein drink, or a carbohydrate drink on building muscle and burning fat after completing weight lifting workouts. All three groups gained muscle, but the milk drinkers got the best results, says researcher Stuart M. Phillips, PhD, associate professor of kinesiology and an exercise physiologist at McMaster University in Hamilton, Ontario, Canada. The
study was funded by the National Dairy Council and published in the Aug. 1 issue of the American Journal of Clinical Nutrition. Study Details Phillips and his colleagues recruited 56 healthy young men, average age 22, and assigned them to drink milk, a soy drink, or a carbohydrate drink immediately after their weight training exercises and then an hour later. "They drank 2 cups each time," Phillips tells WebMD. The drinks were all vanilla-flavored, served in opaque containers, and had an identical number of calories --178 per serving. The milk and soy drinks were matched for protein, fat, and carb content. Each had 18 grams of protein, 1.5 grams of fat, and 23 grams of carbohydrate. Participants weight-trained five days a week for 12 weeks, and all the participants were novices. They had not done any weight training for the past eight months. The exercises were done on standard weight training machines, which worked out all the major muscle groups, with participants increasing repetitions as they gained strength. Each session lasted about one hour. At the study start, the researchers measured each participant's body composition, noting the amount of lean mass and fat mass. They repeated the measurements at the end of the study. The milk drinkers gained the most muscle. "The gains of muscle in the milk group were 8.8 pounds, vs. 6 pounds for the soy group, vs. 5.3 pounds for the control group [drinking the carbohydrate drink]," says Phillips. "The group that drank the milk gained 60% more muscle than the carbohydrate group and 40% more than the soy group," Phillips says. Those who drank milk also had more strength gains than the other two groups in two kinds of individual exercises: knee extensions and hamstring curls. The milk drinkers also lost more body fat. "They lost almost 2 pounds of body fat," he says. "The soy group barely changed in terms of body fat. It was about a third of a pound. In the control group (the carbohydrate drinkers) it was about a pound of body fat lost." Whey Protein Whey protein is a high-quality dairy protein that contains all the amino acids the body requires for muscle protein synthesis. Evidence suggests that whey protein, found naturally in milk, increases muscle protein synthesis which in combination with resistance exercise can improve body composition. Below are summaries of recent studies that further explain the benefits of whey protein.
Whey protein is one of the best sources of branched-chain amino acids (BCAA), including leucine, which has been shown to independently stimulate muscle protein synthesis This review article shares data from the USDA Food Composition Tables that show dairy products are rich sources of BCAAs and whey protein isolate is a leading source of leucine. The author cites several studies that give increasing evidence that BCAAs, specifically leucine, have a unique affect on metabolism that includes regulation of muscle protein synthesis and glucose homeostasis. The impact of BCAAs is proportional to availability and dietary intake. Layman DK. The role of leucine in weight loss diets and glucose homeostasis. Journal of Nutrition. 2003;133:261S-267S. Consuming whey protein after resistance exercise can stimulate protein synthesis Ingestion of amino acids is known to stimulate protein synthesis and result in a positive net muscle protein balance. Tipton and colleagues investigated whether consumption of casein or whey proteins have a similar beneficial effect following resistance exercise. Healthy untrained volunteers were randomly assigned to receive a drink containing either: (1) 20 g casein (N=7); (2) 20 g whey protein (N=9); or (3) placebo (N = 7) one-hour after performing a bout of resistance training. Leg muscle biopsies were taken to measure net muscle protein balance. Consumption of both casein and whey proteins were found to bring about a similar positive net muscle protein balance, indicating that whole protein consumption can stimulate muscle protein synthesis after resistance exercise which over time could lead to increased muscle size and strength. Tipton K, Elliott T, Cree M, Wolf S, Sanford A, Wolfe R. Ingestion of casein and whey proteins result in muscle anabolism after resistance exercise. Medicine & Science in Sports & Exercise. 2004;36(12):2073-2081. Consumption of fluid skim milk promotes greater muscle protein accretion after resistance exercise than does consumption of an isonitrogenous and isoenergetic soy-protein beverage This study examined the effect of consuming a milk or soy beverage on rates of whole body protein synthesis, breakdown, and leucine oxidation, as well as muscle protein synthesis and net muscle protein balance following resistance training in eight young men who regularly participated in weight lifting activities. Volunteers drank fluid milk or a soy protein beverage after a bout of weight lifting. The drinks were made from isolated soy protein or nonfat milk powder and were equal in protein, carbohydrate, fat and caloric content. Results indicate that consuming a protein beverage (soy or milk) following weight lifting resulted in a positive net muscle protein balance and more muscle protein synthesis. Milk consumption after exercise resulted in a greater net muscle protein balance, and 34 percent more
muscle protein synthesis compared to soy. The researchers also hypothesized that a combination of "slow" and "fast" proteins like casein and whey, both found in cow's milk, would be most effective for building muscle. Wilkinson S, Tarnopolsky M, MacDonald M, MacDonald J, Armstrong D, Phillips S. American Journal of Clinical Nutrition. 2007;85:1031 40.