Creatine is one of the most powerful sports nutrition supplements available. It is remarkable in that creatine causes noticeable increases in muscle size and strength within as little as one week of use. To understand how creatine works, you have to know a little about muscle physiology. The immediate source of chemical energy which is used to power muscular contractions is a molecule called ATP, or adenosine triphosphate. When the food you eat is oxidized, or burned, to produce energy, that energy is used to generate ATP. Then the ATP is used to power muscle contractions. A good analogy is a coal-fired generator. Coal is burned to produce heat, which then heats water to make steam, which then turns a turbine to make electricity. The electricity then runs your fan. It’s a process of transforming chemical energy (in the coal) into heat energy (in the steam) into electrical energy (the electricity), and finally into mechanical energy, the air moving from the fan.

In the year 2000, branched-chain amino acids (BCAAs) were among the most intensely researched supplements in sports and medical science. And the news from labs is good. These nutrients, a popular bodybuilding and fitness supplement, now have an even longer list of impressive benefits. For background, BCAAs are l-leucine, l-isoleucine, and l-valine, and they make up about one-third of your muscle protein.