Nutrition
Milk is an excellent source of source of proteinwhich is easily digested and quickly available to the body as a source of energy and for cell and tissue repair. Casein, whey and milk soluble protein are the main types of protein found in milk. French researchers have discovered that the different protein components of milk vary in their digestibility and availability in the body. The combination of casein and whey is digested slowly, so that protein is available for many hours after consumption. Milk-soluble proteins have a very short gastric retention time and release their amino acids to the cells so quickly that they cannot supply the tissue structure with amino acids for a longer period of time after consumption. The conclusion for bodybuilders is that protein supplements made from casein or whey are superior to products made from whole or low-fat milk. (American Journal Clinical Nutrition, 84:1070-1079, 2006)
Protein supplementation before and after training with weights could promote gains in strength and muscle mass. Athletes need about 0.9 to 1.5 grams of protein per kilogram of body weight per day. Excessive protein consumption can impair protein synthesis. However, the correct timing of protein intake is important. A protein intake after training could increase the gains from training, promote recovery and prevent muscle soreness after training.
Researchers at the Indiana University School of Medicine were able to show that an intake of soy or whey protein in rats after endurance training increases protein synthesis by promoting amino acid code sequencing within the muscle cells. The increased protein intake did more than just supply the amino acids needed to build new muscle tissue. It also promoted processes at the cellular level that are involved in making the cells bigger and stronger.
(Journal of Nutrition, 137: 357-362, 2007)
HMB (beta-hydroxi-methylbutyrate) is a metabolic product of the amino acid lycine. More than 10 years ago, Nissen and colleagues (J. Appl. Physoil. 81: 2095-2104, 1996) showed that HMB prevents protein breakdown and promotes muscle hypertrophy in subjects training with weights. Other studies have shown that HMB increases lean body mass (primarily muscle) and reduces body fat mass. The combined simultaneous intake of HMB and creatine was more effective than taking either substance on its own.
However, numerous studies have concluded that HMB has no additional benefit for athletes. Researchers from Canada found that HMB improved maximal oxygen consumption (a measure of aerobic fitness) and facilitated breathing during exercise.
HMB is not as popular as creatine, but it has several beneficial effects that make it an effective bodybuilding supplement.
(International Journal Sports Nutrition Exercise Metabolism, 17: 56-69, 2007)
Muscular dystrophy is a disease characterized by progressive degeneration of muscle tissue due to the absence of dystrophin - a protein that helps muscle cells resist mechanical stress. Doctors can treat this disease with corticosteroids, but this drug also has serious side effects.
Researchers from Germany examined the literature on the effects of creatine monohydrate supplementation on reducing the symptoms of muscular dystrophy. They examined 12 studies with a total of 266 subjects. Creatine improved neuromuscular function and overall quality of life in subjects suffering from dystrophy, while reducing muscle tissue breakdown. Creatine monohydrate increases muscle creatine phosphate levels, which are an important source of energy. It also has a direct influence on protein synthesis and neuromuscular function. Short and medium-term creatine supplementation improves muscle strength in people suffering from muscular dystrophy and is also well tolerated. Creatine is not only an effective supplement for bodybuilders and strength athletes but also has important applications in the field of medicine.
(The Cochrane Database of Systematic Review, published online, issue 1, 2007)
Athletic performance decreases in the heat. Physical activity increases heat production in the body and high ambient temperatures further exacerbate this condition. Adequate hydration (water retention in the body) is a critical factor in controlling body temperature. Creatine and glycerol increase the body's capacity to store water. Researchers from Scotland have found that supplementation with creatine and glycerol (alone or in combination) reduces heart rate, body temperature and perceived exertion during endurance exercise in the heat (90 degrees Fahrenheit (which is about 32 degrees Celsius), 70 percent humidity). While the combination of creatine and glycerol increased water retention in the body the most, creatine alone was just as effective in reducing cardiovascular stress and thermal stress during exercise.
In the past, many sports physicians have warned athletes not to take creatine when exercising in high heat. This study shows that the exact opposite is true: creatine improves heat tolerance.
(International Journal Sports Nutrition Exercise Metabolism, 17: 70-91, 2007)
