Valine is a branched-chain amino acid used to enhance exercise performance, prevent fatigue, improve concentration and reduce protein and muscle breakdown during intense exercise. Branched-chain amino acids have also been used to improve liver cirrhosis, tardive dyskinesia and spinocerebellar degeneration. Branched-chain amino acids are essential and include leucine, isoleucine and valine.
There is some evidence that daily administration of branched-chain amino acids containing leucine, isoleucine and valine can decrease acute symptoms of mania, possibly by attenuating central dopaminergic overactivity and neurotransmission.