Most fitness enthusiasts who have had their sights set high on muscle growth have certainly heard of creatine if they aren’t already taking it. If you’ve taken it and tolerated it well, it’s probably still a part of your pre-workout ritual. And with good reason: Creatine is the most well-documented sports supplement touted for boosting athletic performance and greater gains.

But that’s just the tip of the iceberg. As it turns out, creatine has all sorts of other benefits besides helping bodybuilders squeeze out a few more reps. It has been shown to improve post-exercise recovery, prevent injury, and assist in thermoregulation and rehabilitation. It also can help heal concussions and provide spinal cord neuroprotection.


That’s not all!

The International Society of Sports Nutrition‘s stance on creatine is that its use is safe in addition to its many benefits. Their 2017 review of creatine supplementation indicates successes with regard to “neurodegenerative diseases, diabetes, osteoarthritis, fibromyalgia, aging, brain and heart ischemia, adolescent depression, and pregnancy”.

If you’re still not impressed, read on. If for any reason you had a preconceived notion that taking this supplemental superstar might have a more negative impact than positive, the large body of evidence available suggests otherwise.

What is Creatine?

Creatine is defined as a non-protein amino acid compound found exclusively in vertebrate animals and functions in the formation and recycling of adenosine triphosphate (ATP) in muscle cells and also to a lesser extent, testes, heart, and brain tissue. It is produced in the body by the liver, but once released, 95% is stored in the skeletal muscle tissue. A large percentage (about 65%) of total creatine is in the form of phosphocreatine (PCr)–the form able to be highly mobilized for energy production. The rest is in the form of free creatine (Cr), waiting to be converted into PCr by the enzyme creatine kinase.

Once converted to PCr, the production of ATP via ATP synthase is then possible. ATP is the driver of most cell processes, including muscle contraction, nerve impulses and chemical synthesis. We can produce up to 250g of ATP daily, and surprisingly, the body recycles its own weight in ATP daily via creatine processes. While ATP can be synthesized through several pathways, creatine is required for the production of ATP in order to fuel short bursts of energy .

Our NFPT Manual reminds us: “There are about 4 seconds worth of ATP already stored in the working muscle cells. After this period of sustained muscle contractions, ATP in the working muscle is exhausted and the cells resort to the use of Creatine Phosphate and ADP to create more ATP, providing energy for about another 25-30 seconds.”

When it comes to exercise, the more ATP we have available for use, the more energy we have to perform our workouts. So it follows, the more Cr we have available in our cells, the more ATP can be produced for short, high-intensity exercises such as weight lifting or sprinting.

For an average 70kg human (approximately 155lbs) the total creatine amount (PCr + Cr) found in the muscle averages about 120 mmol/kg of dry muscle mass (mmol = millimole. A mole is an amount of a substance that contains a large number (6.02214078×1023) of molecules or atoms. A millimole is one-thousandth of a mole.) The upper limit that can be maintained in the human body at any given moment is closer to 160 mmol/kg of muscle mass, indicating that there is room for supplementation.

Vegetarians/vegans have been reported to have naturally lower stores (90–110 mmol/kg of dry muscle) and may benefit from creatine supplementation most for normal functioning. Additionally, athletes with high muscle mass and engaging in regular intense activity are more likely to deplete their stores and would benefit from supplementing between 5 and 10 grams a day simply to maintain normal levels.

Don’t get too hung up on these chemical measurements. Suffice it to say, there is an average at which the body measures for creatine levels without supplementation, but it does not reach the body’s threshold of how much it is able to harbor.

Furthermore, about 1-2% of intramuscular creatine is metabolically broken down into creatinine and excreted through the urine. This equates to 1-3 grams of Cr that would need replenishment on a daily basis. Most of that can be gained through high-protein foods such as beef and chicken; the remainder is manufactured in the liver and kidneys. But even with diets garnering the appropriate amount of creatine from food, it still leaves the body’s creatine stores only 60-80% saturated.

To affect athletic performance via increased ATP production and storage making slightly more energy available for intense exercise, additional supplementation of creatine appears to be a reasonable strategy. What does the research say?

Does Creatine Supplementation Really Work?

In order for creatine stores to reach threshold, the muscle stores must be saturated. A loading phase has been studied to observe fast and measurable changes in these stores.

The supplementation of 20-30 grams of creatine a day for up to a week is known as a loading phase to saturate the muscle stores. After that, most folks can take 3-5 grams/daily to maintain those stores, though some athletes may need 5-10 if they work more intensely, more frequently and have above-average muscle mass. Further, creatine is reported to have greater muscle retention rates when consumed with carbohydrates or a carbohydrate + protein.

Loading isn’t necessarily to saturate muscle stores, however. Ingesting a modest 3 grams a day for a month will also saturate stores, albeit more slowly and with less evident performance improvements.

A 1992 study published by Clinical Science tested how levels of supplementation affected subjects who already measured below normal on total creatine levels. They found that a protocol of administering five grams 4-6 times a day for at least two days resulted in a significant rise in total creatine levels, but especially so in the muscles that engaged in heavy exercise. Interestingly, however, no rise in ATP levels was detected.

Other studies have demonstrated that ATP production after the loading phase does indeed significantly increase. For instance, Kurosawa et al (2003) tested subjects’ handgrip strength using a dynamic exercise before and after creatine loading and found that ATP synthesis was highly correlated with Cr supplementation, as was mean power output for the 10-second exercise.

The review of the Journal of International Society of Sports Nutrition mentioned at the beginning of this article cites nearly 30 research articles that support the efficacy of creatine supplementation in improving sports performance across all sorts of populations, from adolescents to seniors, and both men and women—though some evidence suggests women do not gain as much benefit as men.

Still, there has been little evidence to refute its utility in gaining an added muscle-energy boost during workouts and plenty to say that it does. Since creatine is naturally occurring in the body and in our food, there are no legal restrictions on its use for professional sports, and therefore, is a favorite supplement amongst athletes. An estimated 15-50% of athletes and military personnel report using it.

Other Benefits

Recovery and Rehab

The health benefits from creatine supplementation don’t stop at athletic performance. Aside from a boost seen in speed, strength and muscle size from increased energy stores, creatine also appears to speed recovery and reduce injury. The first interesting finding is that taking creatine is better than carbohydrate loading alone in maintaining glycogen stores–a condition known to improve recovery.

Another study measured recovery by testing isokinetic and isometric contractions post-workout in individuals supplementing with creatine, and found that both were higher with supplementation. One study found lower levels of blood markers associated with inflammation and muscle soreness in marathon runners supplementing with creatine compared with controls.

Additional evidence suggests that taking the supplement seems to prevent overtraining symptoms when overdoing it would otherwise result in decreased athletic performance.

For those with injuries or engaging in post-rehab exercise recovery, taking creatine appears to reduce atrophy and boost muscle performance, as you would expect.

Injury Prevention

A study comparing football players both taking creatine or not indicated no ill-effects were experienced by those supplementing, and in fact, they reported “less incidence of cramping, heat illness/dehydration, muscle tightness, muscle strains/pulls, non-contact injuries, and total injuries/missed practices than those not taking creatine”.

Similar findings were replicated among other football, soccer and basketball players refuting the longheld belief that creatine causes dehydration and muscle cramping, among other things.

Dehydration or Hydration?

One area where the accusation holds water is that creatine promotes fluid retention, primarily in the skeletal muscle itself, and can cause weight gain because of this retention. But plenty of research examining if that retention somehow translates into dehydration determined that it unequivocally does not. Even better, it seems to even boost an athlete’s ability to perform in the heat without thermoregulation failure.

Are There Risks of Creatine Supplementation?

Is there any truth to the purported ill-effects of taking creatine on a regular basis? Rumor has it that it can cause a plethora of side effects including (but not limited to):

  • Kidney damage and stones
  • Liver damage
  • Weight gain
  • Dehydration
  • Muscle cramps
  • Digestive problems
  • Compartment syndrome
  • Rhabdomyolysis
  • Bloating

Kreider et al. (2003) determined that long-term use of up to 21 months at recommended dosages did not significantly alter any health markers amongst athletes. And this was compared to a control group as well. They looked at metabolic markers, muscle and liver enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes, as well as renal function.

Basically, almost every study that has tried to find a side effect of creatine usage found none, aside from weight gain, which has been attributed to water retention, if not muscle gain. When creatine supplementation ceases, weight and water retention decreases.

Aside from that, there was little evidence to indicate any ill effects result from taking supplemental Cr. And while looking for bad things, they found good things. I suggest reading the full review on creatine by the ISSN for all the details I didn’t include here, including its many medical applications.

But so, there you have it: creatine is backed by research to be both safe and effective as a supplement.

How to Take It and Who Should

Should you recommend creatine to all of your clients?

I’d say it’s a personal choice and you can start with educating your clients about supplements in general. There are a ton of options out there and anyone can get roped into a too-good-to-be-true promise. For the average weight loss or fitness client, knowing anything about creatine supplementation to start is not only unlikely, but they’ll probably be more inclined to want a supplement geared towards weight loss or energy—products that are actually quite likely to cause damage or contain undisclosed, potentially dangerous ingredients and still don’t promote long term results.

If you have clients serious about putting in the effort to build muscle, improve performance and change their body composition, creatine is a perfectly safe addition to their program. It’s worth mentioning that there are MANY forms of creatine marketed today, each proclaiming to be either fast-absorbing, more bioavailable, less-bloating, etc, etc. The large body of evidence indicates that plain old creatine monohydrate does the job and the others don’t do any better. So, don’t fall victim to advertising ploys.

I just purchased this very basic, inexpensive creatine product (affiliate link!) that comes in powder form for about $11, containing 80 five-gram servings, projected to last 45 days if I do a week loading phase. Those who consider themselves compliant and able to follow a multi-occasion daily protocol should consider implementing the loading phase: Take 5 grams of creatine 4 to 6 times a day for 5 to 7 days. After that, a maintenance dose of 3-5 grams is appropriate for most people. Those with more muscle mass or who perform intense exercise can take up to 10 grams a day.

Women and lighter individuals can probably take it fewer times a day for fewer days for the loading phase, and take 3 grams for the maintenance period. Even athletes under 18 are cleared to take supplemental creatine.

Coupling your creatine supplement with a carb and protein will help the muscles retain more of the compound. Consider mixing it in with a protein shake and eating a banana. Or, take it in water and have a spoonful of peanut butter on a piece of toast. Taking creatine while active should result in noticeable performance gains, but it is worth noting that stopping your supplementation does not result in a drop below baseline levels. I.e., your body is not going to become reliant on the supplementation and stop its own creatine synthesis. Stop taking it and you will probably just return to your baseline level pre-supplementation.

Have you seen differences in your own performance while taking creatine monohydrate?

sports fitness nutrition course


NFPT Study and Reference Manual, The Fundamentals for the Certified Personal Trainer, CPT Seventh Edition, pg 104, (2017).

Greenwood M, et al. Creatine supplementation during college football training does not increase the incidence of cramping or injury. Mol Cell Biochem. 2003;244(1–2):83–8.

Michele Rogers

NFPT Publisher Michele G Rogers, MA, NFPT-CPT and EBFA Barefoot Training Specialist manages and coordinates educational blogs and social media content for NFPT, as well as NFPT exam development. She’s been a personal trainer and health coach for over 20 years fueled by a lifetime passion for all things health and fitness. Her mission is to raise kinesthetic awareness and nurture a mind-body connection, helping people achieve a higher state of health and wellness. After battling and conquering chronic back pain and becoming a parent, Michele aims her training approach to emphasize fluidity of movement, corrective exercise, and pain resolution. She holds a master’s degree in Applied Health Psychology from Northern Arizona University. Follow Michele on Instagram.