Ornithine's Use In Athletics

Ornithine can be made from arginine, and is the precursor of the amino acids glutamic acid, citrulline, and arginine and further to proline and hydroxyproline. With arginine, ornithine is useful in nitrogen (ammonia) metabolism. It has been described as a stimulant for growth hormone release and is thought to help build the immune system, promote wound healing, and support liver regeneration. People who are poorly nourished or who lack protein in their diet may be deficient. Ornithine is usually supplemented along with arginine, as they have similar actions. The most common use is in body builders as a growth hormone stimulant. A dose of 1500?2500 mg. twice daily is required for this type of effect. Side effects might include insomnia.

It is found in milk products and meat, especially chicken. It may cause insomnia, and is contraindicated for schizophrenics. Growth hormone releasers should not be used by anyone who has not grown to their full height unless advised by their physicians. Excess growth hormone will cause the skin to become coarser and thicker, this is reversed when excess GH is withdrawn. Very excessive growth hormone over an extended period of time can cause irreversible enlargement of the joints and lowering of voice pitch due to larynx growth, and may cause a pituitary form of diabetes.

The principal reason for the popular use of Ornithine as a sports supplement is due to its action when combined with Arginine of stimulating muscle development and decreasing body fat. L-ornithine also combines well with L-carnitine to enhance this effect. These amino acids are believed to increase the levels of human growth hormone, promoting muscular growth.

For the strength-trained athlete attempting to increase muscle mass, probably the most important nutritional considerations are to obtain sufficient energy and protein. Adequate amounts of both may be obtained simply by increasing the amount of complex carbohydrates and healthful protein sources in the daily diet.

Although muscle tissue contains numerous nutrients, protein is the major constituent of muscle other than water. However, the other energy nutrients are essential for synthesis of contractile proteins and other regulatory proteins in the cell. Adequate dietary energy and protein are thus two key elements underlying muscle growth.

Ammonia is known to increase in the blood during exercise which can promote the formation of lactic acid which builds up in muscles during exercise and can result in fatigue and muscle soreness. L-ornithine facilitates the release of ammonia from the body via the urine.

Many organisms produce substantial amounts of ammonia as a byproduct of protein catabolism. Many excrete this metabolite as is; this phenomenon is especially predominant among animals which dwell in water. Some animals convert the ammonia into urea using the "ornithine-urea pathway". In mammals, the pathway is confined mostly to cells of the liver.

Ornithine Transcarbamylase Deficiency is part of a urea cycle disorder. A urea cycle disorder is a genetic disorder caused by a deficiency of one of the enzymes in the urea cycle. The urea cycle involves a series of biochemical steps that takes place in the liver, in which nitrogen, a component of protein, is removed from the blood and converted into urea. There are five steps to the urea cycle, each of them requiring a specific enzyme. When one of these enzymes is missing, nitrogen accumulates and is converted into ammonia, a highly toxic substance, instead of urea. Ammonia reaches the brain through the blood, where it may cause irreversible brain damage and/or death. Ornithine transcarbamylase is one of these deficiencies. Urea cycle disorders are tragic illnesses that are characterized by excessive amounts of ammonia in the blood. Without treatment, these disorders can cause behavioral disorders, mental retardation, coma, or even death.

Most of the commercial nutritional products marketed for strength-trained athletes are promoted as a dietary means to influence metabolic processes that stimulate muscle growth and/or facilitate the loss of body fat, primarily by inducing the endogenous production or release of testosterone or human growth hormone (HGH).

There is little or no scientific evidence supporting positive effects on muscle growth, body fat reduction, or strength enhancement in strength-trained athletes for the following nutritional supplements: arginine, lysine, and ornithine (amino acids); ornitine alpha-ketoglutarate (OKG); inosine; choline; yohimbine; "glandulars;" vitamin B 12; carnitine; chromium; boron; magnesium; medium chain triglycerides; omega-3 fatty acids; gamma oryzanol; Smilax. Additional research is needed to support or refute claims made for some of these products, as well as others that may be of interest to strength-trained athletes, e.g., creatine and antioxidant vitamins.

  • Haas, Elson, M.D. Staying Healthy With Nutrition - The Complete Guide to Diet and Nutritional Medicine.
  • Ornithine. Hyperhealth. Health and Nutrition Databank.
  • Melvin H. Williams, Ph.D. NUTRITIONAL SUPPLEMENTS FOR STRENGTH TRAINED ATHLETES SSE#47, Volume 6 (1993), Number 6
  • Osiecki H. Role of Ammonia in Fatigue. Food of the Gods, Hypernutrition for Sport. 1990.

Discuss It!