Creatine is one of the most studied sports supplement with more than 2,000 studies to date. And this research broadly agrees that creatine brings some benefit to most people who take it.
And it's not clear exactly how creatine monohydrate achieves these benefits, as Brad Schoenfeld, Ph.D., CSCS, explains in the article "Ask the Muscle Doc: How Does Creatine Help Build Muscle?" One explanation is that as creatine increases strength gains, it enables the lifters to move more total weight and produce more of what is called "mechanical tension." Mechanical tension is considered one of the main creators of muscle growth.
However, it is also possible that creatine, because it draws water into muscle cells, contributes to another creator of muscle growth, cell swelling. The third of the main mechanisms of muscle growth is muscle damage.
"It is quite possible that creatine can positively influence two or even all three of these mechanisms," writes Schoenfeld.