http://www.nrcresearchpress.com/doi/abs/10.1139/apnm-2016-0178?journalCode=apnm#.V2fxx9SLSt9In this randomized, double-blind, cross-over trial, we evaluated whether 4-week supplementation with guanidinoacetic acid (GAA) is superior to creatine in facilitating creatine levels in healthy men (n = 5). GAA (3.0 g/day) resulted in more powerful rise (up to 16.2%) in tissue creatine levels in vastus medialis muscle, middle-cerebellar peduncle and paracentral grey matter, as compared to creatine (P < 0.05), indicating GAA as a preferred alternative to creatine for improved bioenergetics in energy-demanding tissues.
Never heard of GAA. Will we see it on the market soon?