Amino acids: arginine, lysine, ornithine

Arginine and ornithine are interchangeable amino acids, and lysine is indispensable, which must come with food.

Main functions

• Increase muscle mass.
• Reduce the amount of adipose tissue.
• Increase the secretion of growth hormone.

Theoretically, one can conclude that oral intake of one amino acid or a combination of them will increase the circulation of growth hormone (GH) and insulin. The advantage of high GH and insulin levels is related to their anabolic properties. It was suggested that increased levels of GH and insulin help to increase muscle mass and reduce the amount of adipose tissue.

The concentration of GH increased at the 30th, 60th and 90th minutes of physical activity, but no differences were observed between the groups. At the basal level, acute GH secretion increased after taking an amino acid.

Research results

Fogelholm et al. Studied the consumption of 2 g of arginine, lysine and ornithine, taken 2 times a day. Eleven weightlifters were given an amino acid or a placebo, and the levels of GH and insulin were measured every 24 hours. Peaks in the GH level in the placebo group and the amino acid supplement group did not differ and insulin levels did not increase after supplement intake. The researchers concluded that the ergogenic value of small doses of amino acids is questionable.

Since GH levels decrease with age, Corpas et al. Investigated the effect of oral intake of lysine and arginine on GH in elderly men (69 ± 5 years). Two groups of eight healthy men took 3 grams of arginine and lysine 2 times a day for 14 days. GH levels were measured in blood samples taken every 20 minutes from 2:00 am to 8:00 am. The results showed that both GH and serum insulin levels did not change significantly, therefore, oral administration of arginine and lysine is not a means of increasing GH secretion in older men.

Suminski et al. Studied the effect of amino acid consumption and exercise with overcoming resistance on the concentration of GR in the plasma of young men. Four series of studies were conducted on 16 subjects: in the first, the subjects performed exercises and took a placebo, in the second performed exercises and took an amino acid, in the third they took only the amino acid and, finally, in the fourth placebo only.

Recommendations

Studies have shown that supplements of arginine, lysine and ornithine do not affect GH levels or body composition. The combination of the additives with the load does not increase the GH levels more than it does with the load alone.

Rapid spread of additives containing free amino acids, allowed to consume large amounts of individual amino acids. This situation is impossible with respect to protein foods or protein supplements, since they contain different amino acids. There are no data on the problems associated with the consumption of individual amino acids, except for the syndrome of eosinophilia-myalgia (caused by infected tryptophan). However, large doses of some amino acids can disrupt absorption, cause gastrointestinal disorders and lead to an imbalance in metabolism, so it is prudent to avoid large doses of individual amino acids until their harmlessness is proven.

[1], [2], [3], [4], [5]