BCAA's (Branched Chain Amino Acids) play for the construction and the preservation of muscle mass an important role, because they are a structural fabric as well as energy supplier for the organism. Above all with highly intensive training unities the body also pulls up these essential amino acids for the power production. A sufficient and regular care with BCAA's is absolutely necessary particularly for engaged sportsmen oriented to aim therefore. Above all during the hours after the training the need is very high in these important amino acids and should be covered for the purposes of an optimum muscle increase enough - urgently the than construction material also allows a quicker transport the improved blood circulation after the training to required amino acids to the muscle cells. If BCAA's are taken before the physical load, they allow a harder and more intensive training, because they serve the body than additional energy source. Beside this achievement-rising effect BCAA's, taken before the training, also a muscle dismantling prevent, above all under high physical load, e.g., with athletes hold the diet or are just in a competition preparation. BCAA's are therefore an inalienable food supplement for all seriously training athletes who would like to produce top performances and exhaust her physical potential fully.