What Is Creatine?

Creatine is a naturally occurring compound that is found in humans and most other vertebrates. Creatine’s primary role is to recycle adenosine triphosphate (ATP), which you may realize is the compound that drives muscular contraction in our bodies, but is also responsible for a couple of other roles in the body such as pH buffer in other tissues.

Creatine is mostly produced in our bodies by the liver and kidneys at about a gram per day in younger adults (Brosnan JT, 2011), and can also be consumed through a diet consisting of red meat and fish like tuna and salmon. Most of the creatine in our bodies is stored in our skeletal muscle, where the remainder is distributed throughout the body by the blood.

Creatine supplements used to receive a great number of myths when it first started to be used by a number of athletes, sprinters, and weightlifting athletes. In the last couple of decades, creatine has been thoroughly researched and studied and is also one of the most studied supplements in the world. A review done in 2009 took a large sample of studies and research done on creatine and its effects on “exercise heat tolerance and hydration status” and found “no evidence supports the concept that creatine supplementation either hinders the body’s ability to dissipate heat or negatively affects the athlete’s body fluid balance (Rebecca M Lopez, 2009).”

Another myth tied along with creatine supplementation is kidney damage. In a study done in late 2000, researchers found that not one of their participants “showed any evidence of dysfunction based on serum enzymes and urea production (Poortmans JR, 2000).” With the biggest myths being dispelled by research, the most common side effects of creatine supplementation are an upset stomach when creatine is taken on an empty stomach and possibly some muscle cramping, but these symptoms are usually anecdotal (Poortmans JR, 2000).

How Does Creatine Work?

In order to understand how creatine works, an understanding of some basic bioenergetics is needed. Without going into too much detail, the body can produce ATP through a couple of different pathways. There are the phosphagen system, glycolytic systems, and aerobic systems. Now, depending on what kind of exercise you’re participating in dictates what system is being used the most. During exercise, all three of the systems are in use in a combination of some kind, but each system almost has a specific type of exercise when it is being used the most. Short, intense exercise such as sprinting or weightlifting, the phosphagen system will be used the most. Exercise lasting from about 30 seconds to 2 minutes such as mid distance sprinting and some team sports is when the glycolytic systems will be used. Long term exercise such as longer distance running is when the aerobic system will be used the most. For the rest of this article, we will be looking into the phosphagen system.

Now that we understand some of the bioenergy systems, let’s take a better look into the phosphagen system (also called the phosphocreatine system) and ATP. In order for a skeletal muscle to contract, ATP is needed to actually start the contraction. After the contraction, one of the phosphates is cleaved off and actually used specifically for the contraction. This turns the adenosine triphosphate (ATP) into adenosine diphosphate (ADP). ADP can be used for energy and muscular contraction and turned into adenosine monophosphate (AM), but for the sake of simplicity we’ll just talk about ATP and ADP.

Creatine’s specific job in muscular contraction is to turn ADP into ATP very quickly and efficiently in order to give us an opportunity to produce more energy and muscular contractions. Creatine is a phosphate, meaning that it has a phosphate molecule attached to it. This is why creatine is widely considered a necessary supplement for athletes looking to get bigger and or stronger. Creatine’s phosphate that is attached to it is cleaved off and basically given to ADP in order to make it into ATP, allowing for our muscles to recycle more energy for contraction.

Types of Creatine

Today there are quite a few different types of creatine out on the market, all marketing their advantages compared to another, but with creatine and what makes it better than another, it comes down to how soluble and the absorbability of it in our bodies. The big ones on the market right now are creatine ethyl esters or creatine HCL, and creatine monohydrate. Creatine HCL’s big “advantage” that is marketed is that it is more soluble and absorbed by the body better when compared to monohydrate, but no form of creatine has been shown to be better than another. Some anecdotal evidence has been reported that HCL is absorbed quicker and requires a smaller daily dose than monohydrate, but the price is usually going to be a little bit higher than that of monohydrate.

Creatine monohydrate tends to be the best bang for your buck since you are able to purchase a large quantity, around 200 servings, for around $20. Pill form of creatine tends to be a little bit more, but if you don’t like the grittiness of monohydrate in drink form, pills and capsule forms can be a good purchase.

Proper Supplementation of Creatine Monohydrate

In one study specifically looking at a higher dose of 20g/day for 3 days, then followed by a smaller dose of 10g/day for the remainder of their study, 6 weeks, found that the group receiving the creatine showed significant differences in lean body mass, body weight, and 1-RM bench than compared to their placebo counterparts (Peeters, Lantz, & Mayhew, 1999). In another study that looked at smaller doses, this time with the same loading phase of 20g/day for 3 days, but followed up by 5g/day for the remainder of the study as well, 10 weeks, showed a significant increase in strength and power than those of the placebo group (Pearson, Hambx Wade Russel, & Harris, 1999).

These studies have led to the loading phase of creatine supplementation. A large dose for a short amount of time followed by a smaller, maintenance dose for a longer amount of time, such as 10-20 grams a day for 3 days, followed by 5-10 grams a day for however long your training period.
Another question that is often asked or usually comes along with new creatine uses is if creatine needs to be “cycled” on and off. The answer is no.

Creatine is a naturally occurring compound in our body and has not shown negative side effects of long term use, creatine does not need to be cycled on and off of. As long as adequate water is being consumed by the athlete and the athlete also does not have a history of liver or kidney problems, then creatine does not need to be cycled on and off.

-Tyler Giery BS, CPT


  • Brosnan JT, d. S. (2011). The metabolic burden of creatine synthesis. Amino Acids, 1325-1331.
  • Pearson, D. R., Hambx Wade Russel, D. G., & Harris, T. (1999). Long-Term Effects of Creatine Monohydrate on Strength and Power. Journal of Strength & Conditioning Research.
  • Peeters, B. M., Lantz, C. D., & Mayhew, J. L. (1999). Effect of Oral Creatine Monohydrate and Creatine Phosphate Supplementation on Maximal Strength Indices, Body Composition, and Blood Pressure. Journal of Strength & Conditioning Research.
  • Poortmans JR, F. M. (2000). Adverse effects of creatine supplementation: fact or fiction? Sports Med., 155-170.
  • Rebecca M Lopez, M. A. (2009). Does Creatine Supplementation Hinder Exercise Heat Tolerance or Hydration Status? A Systematic Review With Meta-Analyses. Journal of Athletic Training, 215-223.