You've probably already read enough on creatine to realize that there's no guarantee as to whether or not taking a creatine supplement will actually benefit muscle mass. However, findings point to creatine supporting healthy energy levels in weightlifters, runners and other athletes.
Creatine acts on naturally-occurring ATP (adenosine tri-phosphate) in the body, an energy-containing compound that when fueled by creatine may support your muscles' ability to contract and recover from exertion quickly. Faster muscle recovery often means less time between sets and more gains in one day.
Creatine supplements draw water and fluids to muscles, making them swell and look larger. The effect is usually temporary and subsides in hours. Creatine is essentially a combination of amino acids arginine, glycine and methionine – building blocks of protein in the body.