Bodybuilders who take a few grams of Arginine Alpha Ketoglutarate [AAKG] [molecular formula shown here] before they start lifting weights can perform miraculously well. At least, that's what producers of supplements containing Arginine Alpha Ketoglutarate tell us. But sports scientists at Mississippi State University have refuted this claim.
Arginine Alpha Ketoglutarate is a mixtue of L-Arginine and Alpha Ketoglutarate.
Alpha Ketoglutarate is a compound that is freed in the citric acid cycle, a complex reaction that transforms nutrients into energy. Companies reason that supplements with Alpha Ketoglutarate increase the speed of the citric acid cycle, thus providing the body with more energy. Moreover, Alpha Ketoglutarate perhaps also reduces the amount of glutamine that the cycle uses so that muscles have more glutamine available for growth. But we don't know whether or not that’s true since it's never been studied.
Arginine is a precursor of nitrogen monoxide. This substance makes blood vessels suppler, thus allowing muscles to receive more energy and oxygen while stimulating the creation of muscle tissue by activating the stem cells.
The working of arginine has been tested, but the results of those studies are contradictory. Arginine improves an athlete's performance almost just as often as it doesn't. It's possible that nutritional factors play a role - and that L-arginine works only for people who ingest a lot of phenols.
The researchers gave 8 trained and 8 untrained men about twenty years old 3 gr Arginine Alpha Ketoglutarate. After 45 min they checked to see with how many kg the men could do one bench press [1RM] and how many reps they could do with 60% of that weight [TLV = number of reps times weight]. The researchers repeated their experiment after they had given their subjects a placebo.
The figures above show that supplementation with Arginine Alpha Ketoglutarate had no effect.
"In the current study, acute AAKG supplementation provided no ergogenic benefit, regardless of the subjects' training status", the researchers concluded. "Based on the current study an acute ingestion of AAKG is not recommended for healthy individuals to increase maximal strength and muscular endurance for resistance training exercises."
In 2006 researchers at Baylor University published a human study in which bodybuilders took 12 gr Arginine Alpha Ketoglutarate daily for 8 weeks. There were absolutely no effects on body composition, although the supplement did increase maximum strength.
J Int Soc Sports Nutr. 2012 Apr 17;9(1):17. [Epub ahead of print].