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Whey protein

(Known as Protein powder, Whey protein)

Whey protein is a form of protein derived from milk. It has a very high biological value, rich in essential amino acids, and is also low in fat. Many athletes use whey protein for its beneficial effects on muscle growth and the strength of the immune system.Whey protein can be used as a source of high quality, low fat protein in any diet. Individuals who also want the immune system benefits of whey protein, should consider the whey isolates rather than the cheaper concentrates.Milk is made up of two major proteins - casein (pronounced kay-seen) and whey. Traditionally, whey protein refers to the milk proteins that remain after cheese is made from the casein in milk. The whey proteins are then separated from the liquid whey and purified to various concentrations of whey protein.

Whey protein has been used in a number of animal and human feeding studies, where it has shown benefits in promoting muscle gain, elevating glutathione levels (an antioxidant), and improving exercise performance. Of the two main protein sources found in milk (casein and whey) most studies show that whey protein provides the greatest benefit in terms of muscle growth and exercise performance. In one trial carried in the Journal of Applied Physiology, Canadian scientists found that after three months of supplementation, whey protein was more effective at improving exercise performance than casein [1]. The whey protein group also lost body fat, and reported feeling far more energetic.

Whey protein has also been shown to raise protein synthesis to a greater extent than casein [6]. A European research group also report that whey protein lowers cortisol levels [7]. Cortisol is a hormone released by your adrenal glands in response to either physical or emotional stress. High levels of cortisol will lead to protein breakdown, and will slow muscle growth. Scientists think that the cortisol-lowering effect of whey protein is just one reason why it has such a significant impact on muscle growth.

There are also several different types of whey protein. These are known as whey protein concentrates, whey protein isolates and hydrolyzed whey protein. In general, a whey protein isolate will contain more protein and less carbohydrate (as lactose) and fat compared to a concentrate. One hundred grams of whey protein concentrate, for example, contains roughly 80 grams of protein. The composition of a whey protein isolate is slightly different, containing slightly more protein (90 grams of protein per 100 grams of powder) and less carbohydrate and fat. A hydrolyzed whey protein is one that's been partially "predigested" by being broken down into smaller pieces.

Scientists from Australia report that a whey protein isolate is far superior to casein for muscle growth [8]. Thirteen subjects were given either whey isolate or casein while they took part in a weight-training program for ten weeks. Results showed that the 100% whey isolate was more effective at increasing muscle mass. Test subjects using whey gained over 10 pounds of muscle, while those using casein gained only 2 pounds. Those using whey also gained more strength, although both proteins seemed to prevent the typical drop in plasma glutamine levels that occurs with exercise.

When buying whey protein, check the ingredients label to ensure that whey protein isolate is at the top of the list. If you see the term "whey protein concentrate" listed before "whey protein isolate", then the product will not be as effective as one containing an isolate as the main ingredient.
Extra protein provides no benefit (in terms of muscle growth) for people who do no physical activity. However, regular physical exercise, especially training with weights, will dramatically increase your need for protein.

Writing in the International Journal of Sport Nutrition, Dr. Peter Lemon - a researcher specializing in exercise and protein metabolism - concludes that exercise more than doubles your need for protein. Based on his review of the research, Lemon reports that if you're strength training on a regular basis, you'll need to consume roughly 0.8 grams of protein per pound of bodyweight (or 1.7 grams of protein for every kilogram) [9]. For people who want to build muscle as fast as possible, this figure should be nearer 2.5 grams per kilogram of bodyweight. For example, if you weigh 13 stone (182 pounds, or 83 kilograms), you'll need a maximum of 207 grams of protein daily for maximum results.

For best results, you should be consuming some form of protein every 2-3 hours. This creates a positive nitrogen balance, promoting muscle growth, repair and recovery. Your body responds well to whey protein consumed before and after exercise, with many studies showing that protein is more anabolic (growth promoting) at these times than at any other [10, 11, 12].

Whey protein can be consumed at breakfast time, for example, to increase the protein content of your diet (most breakfast cereals are very low in protein). Whey protein can also be consumed between meals as a high protein snack, or even at bedtime to prevent muscle breakdown during the night.
People who include whey protein in their diet usually report faster gains in muscle strength and size, a stronger immune system (less symptoms of illness or infection), and faster recovery between training sessions.Some research shows that whey protein combined with Creatine is more effective than either supplement taken alone [13]. Whey protein can also be combined with most supplements that promote muscle growth, including HMB, Beta-Ecdysterone, and 5-Methyl-7-Methoxy-Isoflavone.

1. Lands, L.C., Grey, V.L., & Smountas, A.A. (1999). Effect of supplementation with a cysteine donor on muscular performance. Journal of Applied Physiology, 87, 1381-1385
2. Lemon, P.W.R. (1998). Effects of exercise on dietary protein requirements. International Journal of Sport Nutrition, 8, 426-447
3. Skov, A.R., Toubro, S., Ronn, B., Holm, L., & Astrup, A. (1999). Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity. International Journal of Obesity, 23, 528-536
4. Wolfe, R.R. (2000). Protein supplements and exercise. American Journal of Clinical Nutrition, 72, 551S-557S
5. Lemon, P.W.R. (1998). Effects of exercise on dietary protein requirements. International Journal of Sport Nutrition, 8, 426-447
6. Boirie, Y., Dangin, M., Gachon, P., Vasson, M.P., Maubois, J.L., & Beaufrere, B. (1997). Slow and fast dietary proteins modulate postprandial protein accretion. Proceedings of the National Academy of Sciences, 94, 14930-14935
7. Markus, C.R., Olivier, B., Panhuysen, G.E.M., Gugten, J.V.D., Alles, M.S., Tuiten, A., Westenberg, H.G.M., Fekkes, D., Koppeschaar, H.F., & de Haan, E.E.H.F. (2000). The bovine protein alpha-lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids, and in vulnerable subjects raises brain serotonin activity, reduces cortisol concentration, and improves mood under stress. American Journal of Clinical Nutrition, 71, 1536-1544
8. Cribb, P. J., Williams, A. D., Hayes, A., & Carey, F. (2002) The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine. Medicine and Science in Sports and Exercise, 34, S1688
9. Lemon, P.W.R. (1998). Effects of exercise on dietary protein requirements. International Journal of Sport Nutrition, 8, 426-447
10. Chandler, R.M., Byrne, H.K., Patterson, J.G., & Ivy, J.L. (1994). Dietary supplements affect the anabolic hormones after weight-training exercise. Journal of Applied Physiology, 76, 839-345
11. Levenhagen, D.K., Carr, C., Carlson, M.G., Maron, D.J., Borel, M.J., & Flakoll, P.J. (2002). Postexercise protein intake enhances whole-body and leg protein accretion in humans. Medicine and Science in Sports and Exercise, 34, 828-837
12. Tipton, K.D. & Wolfe, R.R. (2001). Exercise, protein metabolism, and muscle growth. International Journal of Sport Nutrition and Exercise Metabolism, 11, 109-132
13. Burke, D.G., Chilibeck, P.D., Davidson, K.S., Candow, D.G., Farthing, J., & Smith-Palmer, T. (2001). The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength. International Journal of Sport Nutrition and Exercise Metabolism, 11, 349-364

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