Athletes engage in strenuous training to accomplish the goals of their sport. This strenuous training essentially amounts to trauma to the body, in that the human body interprets every strenuous work-out as a threat to its survival. It is known that muscle damage, caused by training, releases the catabolic hormone prostaglandin-E2. Training also causes the release of adrenocorticotropin (ACTH), which is a pituitary hormone. The presence of increased levels of ACTH increases the production of the catabolic hormone cortisol. Cortisol is also known as hydrocortisone, which is a glucocorticoid of the adrenal cortex that is a derivative of cortisone and is used in the treatment of rheumatoid arthritis. Thus, cortisol is a naturally occurring anti-inflammatory steroid. This catabolic hormone results in the release of amino acids from muscle tissue and prevents absorption of glucose. Cortisol, as a catabolic stress hormone, cannibalizes muscle tissue. High cortisol levels also result in the breakdown of connective tissue, lowered immunity and reduced muscle RNA synthesis. While cortisol may be a detriment to the athlete, scientists have conjectured that when the human body is stressed or traumatized, it triggers a "fight or flight" survival response. The biological design of cortisol is such that when a human is threatened, cortisol levels rise and mobilize the body for action by breaking down fat and muscle stores for emergency energy. Cortisol also reduces swelling in the event of injury. After the threat or trauma has subsided, cortisol levels return to normal. The cortisol-stress relationship is designed for intermittent physical threats and not the constant stimulation provided by today's aggressive athletes. Ongoing training results in cortisol levels that do not return to normal for extended periods of time and thereby result in the breakdown or loss of muscle tissue.
After strenuous exercise, muscle tissue enters a stage of rapid nitrogen absorption in the form of amino acids and small peptides in order to rebuild the muscle fibers, grow and add new muscle fibers. During this period of repair and growth, it is important that the muscle cells have available to them sufficient levels of nitrogen in the form of amino acids. While the total level of amino nitrogen is important, the ratios of the various amino acids is even more important.
Athletes that over-train sometimes enter into a catabolic condition. Muscle catabolism occurs when the athlete enters a negative nitrogen balance. People on diets usually have a negative nitrogen balance and therefore lose muscle when they lose weight. In contrast, a positive nitrogen balance means the animal has enough nitrogen left over to synthesize muscle proteins.
Various organizations have propounded a list of essential amino acids which are required on a daily basis for proper nutrition. These amino acid requirements vary throughout the growth cycle of all animals. Human muscle tissue is made up of specific amino acids and at specific ratios. If any of these amino acids are missing or deficient, the muscles will not grow, will grow slowly and may even begin to breakdown. However, if the animal is supplied with adequate amounts of protein that contain all of the muscle amino acids, this protein or source of amino nitrogen will be able to support rapid muscle recovery and growth.
The amino acids leucine, isoleucine and valine are the branched chain amino acids and are necessary for a positive nitrogen balance and muscle growth. The branched chain amino acids are lost at significant levels during strenuous exercise and therefore it is critical that they be available during the anabolic state.
The present invention is based in part, upon the discovery that the use of pyruvate in combination with an anabolic protein composition, produces a synergistic effect in increasing the lean body mass or muscle tissue of a mammal consuming same while at the same time decreasing the deposition of fat in the body.
As used herein and the claims, the term "pyruvate" means any salt or ester of pyruvic acid. Pyruvic acid has the formula: ##STR1##
Pyruvic acid is a colorless liquid with an odor resembling that of acetic acid and has a melting point of 13.degree. C. Pyruvic acid is an intermediate in the breakdown of sugars to alcohol by yeast. The mineral salts of pyruvic acid, such as magnesium pyruvate or calcium pyruvate or mixtures thereof are useful in the present invention. Sodium pyruvate is not especially preferred as it is known that sodium is associated with various negative medical conditions such as high blood pressure, water retention and heart disease. Further, certain athletes, such as bodybuilders, desire to present a defined visual image of their body which shows muscle definition and thus, the water retention properties of the sodium salt are not beneficial. Pyruvate precursors in the form of pyruvamides or pyruvyl-amino acids are also useful in the present invention. Pyruvyl-glycine is representative of the useful pyruvyl-amino acids.
Pyruvate has a number of useful applications in medicine. Pyruvate has been described for retarding fatty deposits in livers (U.S. Pat. No. 4,158,057); for treating diabetes (U.S. Pat. No. 4,874,790); for retarding weight gain (U.S. Pat. Nos. 4,812,879, 4,548,937, and 4,351,835); to increase body protein concentrations in a mammal (U.S. Pat. No. 4,415,576); for treating cardiac patients to increase the cardiac output without accompanying increase in cardiac oxygen demand (U.S. No. Pat. 5,294,641); for extending athletic endurance (U.S. Pat. No. 4,315,835); for retarding cholesterol increase (U.S. Pat. No. 5,134,162); for inhibiting growth and spread of malignancy and retarding DNA breaks (U.S. application Ser. No. 08/194,857 filed February 14, 1994); and for inhibiting generation of free radicals (U.S. application Ser. No. 08/286,946 filed Aug. 8, 1994). All of these references are incorporated herein by reference.
U.S. Pat. 4,981,687 discloses compositions and methods for achieving improved physiological response to exercise. More specifically, this patent teaches a beverage comprising water, sugar, electrolytes, glycerol and pyruvate; and its use to ameliorate the effects of physical exertion. The teachings of U.S. Pat. No. 4,981,687 are incorporated herein by reference.
U.S. Pat. No. 5,089,477 discloses the use of pyruvate in a liquid composition that is used to prevent weight loss in agricultural animals resulting from dehydration.
U.S. Pat. No. 5,147,650 and U.S. Pat. No. 5,238,684 discloses and claims a fluid composition comprising water, electrolytes, sugar, glycerol, lactate and pyruvate. The teachings of U.S. Pat. Nos. 5,147,650 and 5,238,684 are incorporated herein by reference.
U.S. Pat. No. 5,236,712 discloses and claims a beverage containing water, electrolytes, pyruvate and alanine in a concentration of from about 0.5% to about 10%. The teachings of U.S. Pat. No. 5,236,712 are incorporated herein by reference.
Pyruvate in various forms has been proposed for enteral administration and for parenteral administration. Typically, pyruvates are available in the form of salts, for example, calcium pyruvate and sodium pyruvate. U.S. Pat. Nos. 5,283,260 and 5,256,697 disclose uses for the pyruvyl-amino acids and methods for their production.
Pyruvate has been administered to mammals enterally or parenterally typically at superphysiological levels. The amount of pyruvate administered generally ranges from 1 to 20% of the mammal's caloric intake. For enteral dosage, the pyruvate may be disbursed or dissolved in a beverage product or may be included in cookies, candies or other foods. Pyruvate may also be introduced as an aqueous solution parenterally.
The amino acid composition of numerous proteins, biologically active polypeptides and foods, has been known for some time. One pre-eminent monograph on this subject is the Amino Acid Handbook by Richard J. Block, C. C. Thomas, publisher, 1956 (Library of Congress Catalog Card No. 56-9104). On page 343 at Table II, the approximate amino acid composition of mammalian muscle proteins on average, is set forth as follows:
______________________________________ Amino Acid Grams/100 gm of Protein ______________________________________ Arginine 6.6 Histidine 2.8 Lysine 8.5 Tyrosine 3.1 Tryptophan 1.1 Phenylalanine 4.5 Cystine 1.4 Methionine 2.5 Serine 5.1 Threonine 4.6 Leucine 8.0 Isoleucine 4.7 Valine 5.5 Glutamic Acid 14.6 Aspartic Acid 8.0 Glycine 5.0 Alanine 6.5 Proline 5.0 Hydroxyproline 4.7 ______________________________________
On pages 272-273, the amino acid profile of human muscle tissue is set forth.
Protein supplementation for serious athletes, such as body builders, is well accepted. Typically recommended dosages range between 2.0 and 3.5 gms of quality protein per kilogram of body weight per day. Numerous sources for the protein supplements are known, such as milk, egg, soy, beef and vegetable protein. Isolated fractions of these sources are also known such as ion-exchange whey protein, caseinates, whey protein concentrates, immunoglobulin and egg albumin. Protein supplements typically are provided as powders or tablets. It is also known to provide protein supplementation in the form of peptides (hydrolyzed protein) or even free amino acids. These approaches have two major limitations; cost and taste. While the use of pyruvate is known for various medical indications and the use of protein supplements are known to increase muscle mass, the prior art has failed to recognize or even consider the combination of pyruvate with an anabolic protein composition. The anabolic protein composition of the present invention is prepared through the combination of various proteins, peptides or amino acid sources to arrive at an amino acid profile that parallels the amino acid profile of human muscle tissue. Consumption of the anabolic protein composition will result in an increase in muscle mass, less catabolism of muscle tissue after strenuous exercise or as a result of disease, and quicker muscle cell restoration. Even more surprising are the synergistic results that can be achieved when pyruvate is combined with the anabolic protein composition of this invention. An additional aspect of the present invention is that the anabolic protein composition alone or in combination with pyruvate can lessen the catabolic effects of diseases such as cancer and AIDS. The prior art has not disclosed or suggested the compositions and methods of the present invention.