Because GABA can promote relaxation, it can provide a number of benefits. GABA is able to promote lean muscle, as well as mood and relaxation.*
Increased levels of GABA can promote relaxation.  GABA can help reduce the psychological effects of negativity as well.  In one study, subjects fed choclate infused with GABA saw a much faster recovery of heart rate variability after facing acute psychological demands.* 
Individuals should take 250mg of GABA up to three times per day. Individuals should start with one dose per day and increase as needed.