By Michael Ormsbee, PhD, Florida State University

Edited by Kate Findley and proofread by Angela Shoemaker, The Great Courses Daily

In addition to weight loss supplements, supplements thought to increase muscle mass have also become popular in recent years. Professor Ormsbee examines creatine or creatine monohydrate, one the most popular supplements ever produced and the most thoroughly researched of any supplement.

What Is Creatine?

We produce creatine naturally in the liver and the kidneys. It is stored as free creatine or bound to a phosphate molecule in skeletal muscle. 

Naturally, the creatine phosphate energy system is used to provide energy for maximal intensity, short duration exercise. Creatine supplies a phosphate to adenosine-di-phosphate to create adenosine-triphosphate (ATP)—the energy we need to do everything.

As a supplement, creatine is often used to build muscle, improve strength and power, and increase anaerobic, short-duration activities like powerlifting or sprinting. The standard serving of creatine is five grams (g), which is equal to the amount of creatine of about 2.5 pounds (lbs) of raw meat. Obviously, it’s much easier to take one tiny scoop of creatine than eat an entire plate of steak.

Several forms of creatine exist on the market, but the one that has the most research support and effectiveness is creatine monohydrate. Several hundred peer-reviewed research studies have evaluated this form, and more than 70% of those studies show a significant improvement in exercise capacity and increases in muscle mass. 

Creatine and Muscle Mass Studies

“In my lab, we had 29 healthy resistance-trained young men consume 21 g of a multi-ingredient performance supplement, which contained creatine, for six weeks,” Professor Ormsbee said. “During this time, they also lifted weights three times per week. The results of this study showed a significant 4.7% increase in muscle mass and a 1.6% average decrease in total fat mass.”

The good news is that creatine seems to work in both younger and older people. In fact, men and women over age 65 who took five g of creatine monohydrate per day for two weeks and lifted weights three times per week had a significant increase in muscle mass and overall strength. There was an average increase of almost four lbs, or 1.8 kg, of muscle mass in the creatine group compared to less than a one lb, or 0.45 kg, increase in the placebo group.

Creatine has even been studied in children. One study had 16 young teenage male swimmers compete in two all-out, 100% effort 100-meter swims. 

After supplementation with 20 g per day of creatine monohydrate for five days, there was a two-second improvement in time to complete the two sprints. Almost no time change was reported in the placebo group.

Most experts attribute the beneficial changes to body composition and performance from creatine to the improved ability to do more quality work during exercise. However, research also shows some improvements to actual cellular processes for muscle gain, too. Due to the repeatable success of creatine use for improving both body composition and performance, creatine is currently being studied and used with great interest for clinical populations and in disease prevention.

Other Creatine Uses

Creatine has now been shown to improve muscle mass and outcomes in people with muscular dystrophy, leukemia, traumatic brain injury, and infants born with errors of normal metabolic function. Creatine doses similar to what’s been discussed have been documented to enter your central nervous system and influence brain concentrations of creatine phosphate after both seven and 28 days of supplementation. Because creatine enters your brain, it has some evidence to support a positive effect in cases of traumatic brain injury and even some evidence for stroke patients to improve brain function.

In addition, patients with muscular dystrophy are now shown to benefit from creatine supplementation as it improves nerve function, muscle mass, muscle strength, and power. Even in traditional cases of sarcopenia, or the age-related loss in muscle mass, including creatine and resistance training is shown to increase muscle mass and decrease fat mass.

Creatine Safety Considerations

A common myth is that creatine is a steroid and will damage your kidneys. Creatine is not a steroid: It is simply the combination of three amino acids. 

The research shows that creatine is safe and effective among young and old, male and female, and healthy and diseased populations. In the absence of any pre-existing conditions like kidney disease, creatine is a supplement that has consistently proved beneficial.

The most common side effect reported is weight gain. However, this is probably the type of weight gain that you want because creatine increases muscle mass. 

Keep in mind that the ratio of muscle mass to fat is more important than body weight. Also, some cases of gastrointestinal upset have been noted in the literature. The most common dose is five g per day—about one tbsp.

Research shows that creatine builds and preserves muscle mass, so it may be an ideal supplement across the lifespan stages, and not just for young people trying to put on muscle. Because so many people lose muscle as they age, it might be a good idea to use creatine to try and prevent some of the muscle loss. 

This article was edited by Kate Findley, Writer for The Great Courses Daily, and proofread by Angela Shoemaker, Proofreader and Copy Editor for The Great Courses Daily.

Michael Ormsbee is an Associate Professor in the Department of Nutrition, Food, and Exercise Sciences and Interim Director of the Institute of Sports Sciences and Medicine in the College of Human Sciences at Florida State University. He received his MS in Exercise Physiology from South Dakota State University and his PhD in Bioenergetics from East Carolina University.