You may or may not know, but creatine has a little brother—glycocyamine [aka, guanidinoacetic acid (GAA)], which seems to be a promising new performance-enhancing supplement.
In the body, GAA is produced by the kidneys and pancreas and is a natural precursor to creatine production in the liver. Excitement for GAA as a new fitness supplement comes from the fact that it is essential for energy production in skeletal muscle, it has high oral bioavailability, and it can significantly boost the body’s creatine production. In 2013, a study published in International Journal of Medical Sciences confirmed the creatine boosting effect of supplemental GAA, where the authors reported up to a 50% increase in fasting serum creatine after 6 weeks of supplementation. Although research on GAA supplementation in unhealthy populations dates back to the 1950’s, up to recently there have been no studies investigating its performance enhancing effects in healthy humans.
A most recent randomized, double-blinded, and placebo controlled study published in the Journal of Investigative Medicine provides some of the newest data supporting the use of GAA as an ergogenic aid. In this collaborative study, researchers from Serbia and USA hypothesized that supplemental GAA may enhance exercise performance in humans in a dose dependent manner. They reported that 6 weeks of GAA supplementation (up to 4.8g/day), without a combined exercise program, improved muscular fitness by up to approximately 25%. Most notable were increases in handgrip strength and maximum number of repetitions performed during bench press (to failure). Interestingly, there were no differences in lower body strength with GAA supplementation versus placebo.
ACTION POINT: This latest study provides novel data illustrating that 6 weeks of GAA can improve upper body strength and endurance without training. It will be interesting to see how improvements in strength develop when GAA is taken in combination with a structured resistance-training program—stay tuned, as more research comes out.
Although the current study showed that 6 weeks of GAA was safe and did not adversely affect liver health—before jumping on the bandwagon you must consider that there are health warnings to long-term GAA supplementation on its own. GAA causes increases in the body’s homocysteine levels, which (in the long-term) can promote cardiovascular disease. One way to safely avoid elevations in homocysteine is to take betaine (aka trimethylglycene) with GAA in a 4:1 (betaine:GAA) ratio.
Ostojic SM, Niess B, Stojanovic M, et al. Creatine metabolism and safety profiles after six-week oral guanidinoacetic acid administration in healthy humans. Int J Med Sci. 2013;10:141–147.
Ostojic SM, Stojanovic MD, Hoffman JR. Six-Week Oral Guanidinoacetic Acid Administration Improves Muscular Performance in Healthy Volunteers. J Investig Med. 2015 Jun 15. [Epub ahead of print]