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Ornithine alpha-ketoglutarate

Ornithine alphaketoglutarate(OKG) is formed from two molecules of ornithine and one molecule of alphaketoglutarate. Supplementation with OKG reduces muscle protein catabolism and/or increases synthesis, depending on the metabolic situation. OKG has an anti-catabolic effect that helps to restore the negative nitrogen balance of muscle cells. It increases the plasma concentrations of, for example, arginine, leucine, isoleucine, tyrosine, glutamine, proline and ornithine. Some studies have shown that these amino acids have anabolic properties (anabolic effect) and thus have an anti-catabolic effect. OKG also increases the release of insulin, which in turn triggers an increased transport of amino acids and nutrients into the muscle cells. It also ensures the breakdown of ammonia, a performance-reducing end product of protein metabolism.

As far as I know, there have been no studies on athletes in relation to OKG. We have to refer to the medical studies. Some studies have shown that OKG increases growth hormone levels, but it is still unclear if this is true in athletes. The most interesting aspect of OKG is that it helps to increase glutamine levels in muscle cells. As I mentioned in my article on glutamine, high levels of glutamine have an anti-catabolic effect, especially in people who are under stress but especially in athletes who train hard. Both ornithine and alpha-ketoglutarate help to cleanse the body of excess ammonia. Further studies have shown that OKG has a positive effect on the immune system due to the increased amount of arginine in the bloodstream. However, many more studies are needed to determine the effect of OKG on the immune system, which is influenced by many hormonal factors.

As with all supplements, the dosage depends on your weight (muscle mass), activity level and food intake. I recommend 10-20 grams per day in two doses. Once about half an hour before training and once before bedtime. Since the biggest growth hormone boost occurs about an hour after falling asleep, it makes the most sense to take it shortly before going to bed. Take OKG together with carbohydrates to increase the effect. There are no known side effects at the recommended dose. Higher doses may cause stomach problems and diarrhea. OKG is a good supplement for athletes during hard training and/or dieting.

References

  1. Cynober L (1991) Ornithine alpha-ketoglutarate in nutritional support. Nutrition 7: 313-22
  2. Colgan M (1993) Optimum Sports Nutrition, Advanced Research Press, New York
  3. Colgan M (1994) OKG-Caveat Emptor. Muscular Development 3/94
  4. Feliciano, J (1994) Ornithine alpha-ketoglutarate. Muscle & Fitness 2/94