The essential amino acid
A leucine is one of three branched-chain amino acids (BCAAs). Unlike other aminos, the liver doesn't break down BCAAs (which also include isoleucine and valine). Therefore, as you take more them, more are available for your muscles to use. Leucine is considered by many scientists to be the MV!' of the three BCAAs, because it not only serves as an essential building block for protein in the body, as in muscle cells, but it also plays many other critical roles. So yes, leucine is very beneficial for bodybuilders.
Research shows that leucine supplementation boosts muscle growth by increasing insulin release. Insulin is an anabolic hormone that is essential for allowing key nutrients, such as glucose, amino acids and creatine, to enter muscle cells.
Furthermore, insulin turns on biochemical pathways that increase protein synthesis - that means muscle growth. Originally, it was thought that leucine played a role in protein synthesis via its effect on insulin secretion.
New research, however, shows that leucine itself directly kick- starts key biochemical steps in muscle cells that lead to greater muscle protein synthesis. Another benefit of leucine for bodybuilders is related to fat loss. When calories are reduced during dieting, leucine from muscle tissue is broken down and used to ultimately produce glucose in the liver.
Therefore, taking extra leucine during a diet can spare muscle leucine and thus muscle size, while providing a form of energy (through its conversion to glucose in the liver). Those on a low-carb diet should definitely use leucine to help simultaneously build muscle and lose fat.
Supplementing with leucine helps provide an alternative form of glucose, spares muscle mass and directly stimulates muscle growth. The most important time to take it is immediately after workouts. This is the time to get insulin levels up and boost protein synthesis. Go with 5-10grams(g).
Another good time to get in 5-10g is first thing in the morning to help stop the breakdown of muscle tissue that occurs during sleep due to the overnight fast. Look for products that allow for an easy intake of 5-10g, such as MuscleTech's LEUKIC, which supplies 7.2 g of high-quality leucine in the form of L-leucine-ketoisocaproic acid calcium.