Creatine Monohydrate: What is it & What are its benefits?
Creatine Monohydrate: What is it & What are its benefits?
Introduction
If you have a keen interest in fitness, chances are you have heard about Creatine. Along with the huge amount of research that exists on Creatine use, there is still confusion and misinformation regarding its usage, safety, efficacy, and effects on health and performance.
Creatine is a naturally occurring compound in the human body, primarily stored in skeletal muscle. It can be derived in small amounts from food but it is more widely known as a dietary supplement. It is commonly used by athletes, weightlifters, bodybuilders and regular gym goers (1). However, it can be challenging to understand what Creatine is and whether it is safe and effective.
In this definitive guide to Creatine, we will explore the benefits, risks, and science behind Creatine to provide you with all the information you need to make an informed decision on whether Creatine is right for you.
What is Creatine?
Creatine is a dietary supplement that is used to improve exercise performance and increase muscle mass. It is a combination of three different amino acids: glycine, arginine, and methionine. It is primarily made in the liver, and to a lesser extent in the kidneys and pancreas [2]. This synthesis process ensures the maintenance of Creatine levels in the body, with about 1 gram of Creatine being produced endogenously daily.
Creatine supplements, such as creatine monohydrate, are manufactured synthetically using raw materials sarcosine and cyanamide. Please don’t confuse this with cyanide. These ingredients are heated and pressured to form Creatine crystals, which are then purified, vacuum dried, and milled into a fine powder for better dissolvability.
What are the different forms of Creatine?
There are several types of Creatine available. Here are the most common ones:
1. Creatine Monohydrate: This is the most widely used and well-researched form of Creatine. It is made up of one Creatine molecule and one water molecule and is considered the default option for Creatine supplementation. This is what we use in MARCHON Creatine powder.
2. Creatine Hydrochloride (HCl): This form of Creatine is made by binding Creatine to parts of hydrochloride molecules. It is believed to be more water-soluble than other forms of Creatine, which may make it easier to absorb (3). However there are no published studies on Creatine HCL on humans.
3. Buffered Creatine: This is Creatine monohydrate that has been mixed with an alkaline powder, such as sodium bicarbonate, to improve its stability in the stomach. However, research has found no significant differences in effectiveness between buffered Creatine and Creatine monohydrate[4].
4. Micronised Creatine: This is Creatine monohydrate that has been processed to have smaller particle sizes, which may make it easier to dissolve in water and absorb [5]. Once again the evidence doesn’t stack up to suggest this is a superior form compared to Creatine monohydrate (6)
5. Creatine Ethyl Ester (CEE): This is Creatine that has been combined with an ethyl group to increase the absorption (7). However, even though the principle behind this is correct, the research is yet to support this claim (8)
6. Liquid Creatine: This is Creatine that has been dissolved in liquid, such as water or juice. However, liquid Creatine is not as stable as other forms of Creatine and may break down into creatinine, a waste product, before it can be absorbed. The research that has tested Creatine serum against Creatine monohydrate powder has shown that Creatine Monohydrate produces superior results (9, 10)
7. Creatine Magnesium Chelate: This is Creatine that has been combined with magnesium. However, research on this form of Creatine is limited and shows no further benefit than Creatine monohydrate [11].
It is important to note that Creatine monohydrate, like MARCHON Creatine, is the most widely used and well-researched form of Creatine, and most studies (like this 2022 meta analysis on different forms of Creatine) recommend its safety and efficacy over other types.
How Creatine Monohydrate Works in the Body
Understanding how Creatine monohydrate works in the body involves knowing its function in energy production and muscle physiology.
ATP Regeneration:
The primary function of Creatine monohydrate in the body is to assist in the production of adenosine triphosphate (ATP). ATP is often referred to as the "energy currency" of cells because it provides the energy needed for various cellular processes. When you perform activities that require rapid and intense bursts of energy, such as weightlifting or sprinting, ATP is the primary source of fuel for your muscles.
Creatine monohydrate plays a key role in regenerating ATP during these short bursts of high-intensity exercise. Here's how it works:
- When you engage in intense physical activity, ATP is rapidly broken down to release energy.
- Creatine monohydrate stored in your muscles as phosphoCreatine donates a phosphate group to ADP (adenosine diphosphate), converting it back into ATP.
- This regenerated ATP can be used again for immediate energy, allowing you to sustain a high-intensity effort.
This process of ATP regeneration is vital because the body's natural ATP stores are limited and can be depleted quickly during intense exercise.
By facilitating ATP regeneration, Creatine monohydrate can improve your muscle cells' ability to produce energy during short bursts of intense exercise (1).
Muscle Growth and Recovery:
Creatine monohydrate may also have an impact on muscle growth and recovery. Although the mechanism is not fully understood, it is thought to contribute to these processes in the following ways:
- Increased water content in muscle cells: Creatine supplementation can lead to increased water retention within muscle cells. This may contribute to a temporary increase in muscle size, known as cell volumisation which is considered a key stimulus for cell growth (12)
- Promotion of muscle protein synthesis: Some studies suggest that Creatine may enhance the process of muscle protein synthesis, which is essential for muscle growth and repair but more research is needed to confirm this mechanism.
- Reduction in muscle cell damage: Creatine supplementation has been associated with reduced markers of muscle cell damage and inflammation after strenuous exercise, which may lead to quicker recovery (13).
Benefits of Creatine Monohydrate
There are several hundred research papers that have studied the effects of Creatine with overwhelmingly positive results. Some of the potential ergogenic benefits of Creatine supplementation are
- Increased single and repetitive sprint performance
- Increased work performed during sets of maximal effort muscle contractions
- Increased muscle mass and strength adaptations during training
- Enhanced glycogen synthesis
- Increased anaerobic threshold
- Possible enhancement of aerobic capacity via greater shuttling of ATP from mitochondria
- Increased work capacity
- Enhanced recovery
- Greater training tolerance
(Adapted from Kreider et al. 2017 - Creatine Position stand (1)
One key takeaway from the research is that the benefits are seen in both males and females, trained and untrained individuals alongside young and the older populations. (1, 14 ,16). The research is still male dominated in terms of participants but Abbie Smith Ryans Review titled Creatine Supplementation in Women’s Health: A Lifespan Perspective outlines all the research for females. (15)
Now, let’s break down some of the research in regard to specific goals.
May enhance strength and power performance
An excellent paper by Kreider et al, 2003 summarised various studies and found that around 70% showed some improvement in exercise performance, which is pretty incredible for one supplement.
The extent of performance enhancement varies, influenced by factors such as dosage, the athlete's training level, and specific exercise conditions like intensity and duration. Generally, the literature points to performance boosts of about 10%–15% (1). More detailed findings include increases of 5%–15% in areas like maximal power, strength, anaerobic capacity, and work output in repeated sprints, while single sprint efforts show smaller gains, typically between 1% and 5%.
The primary mechanism behind these positive outcomes for Creatine supplementation appear to be attributable, in part, to increases in intramuscular phosphoCreatine (PCr) concentrations (17). Due to its potential not only to enhance strength and power output but also to enhance recovery from intense intermittent exercise, Creatine supplementation has been shown to allow for increased volumes of work and increased work output during resistance training, which may then translate into greater strength gains (18,19,20).
This is one of the key points to understand that Creatine can directly and indirectly support strength and power performance. Directly through energy metabolism and indirectly through improving your ability to train at a higher intensity and volume.
Furthermore Creatine supplementation has been shown to be effective when taken both short term or long term.
With regard to short term (under 2 weeks of supplementation) a recent systematic review identified 60 studies that adhered to rigorous criteria, including randomized controlled designs and a double-blind, placebo-controlled methodology, to investigate Creatine's impact on lower limb performance. The analysis revealed an effect size of 0.336 for strength gains in back squat exercises and 0.297 for leg press exercises. Additionally, the effect size for increased quadriceps strength was noted at 0.266, with a general effect size for overall lower limb strength also at 0.266 (21). These findings were consistent across various populations and supplementation protocols, underscoring the broad effectiveness of Creatine supplementation.
In a subsequent review by the same team, 53 studies were examined, this time focusing on upper limb strength enhancements due to Creatine supplementation. This meta-analysis found effect sizes of 0.265 for bench press and 0.677 for chest press strength improvements. The effect sizes for pectoral exercises and overall upper limb strength were 0.289 and 0.317, respectively, again demonstrating Creatine's effectiveness across different demographic and supplementation conditions (22).
For context, effect size is the difference between two means relative to the standard deviation, general guidelines suggest:
- Small effect size: d = 0.2
- Medium effect size: d = 0.5
- Large effect size: d = 0.8
It's important to note that these thresholds are not absolute and should be interpreted within the context of the specific field of study. In some areas, even a small effect size can be meaningful, especially in large-scale studies or those with significant practical implications, such as in education or clinical settings where even small improvements can have a substantial impact.
In the context of Creatine supplementation and exercise performance, effect sizes in the range of 0.2 to 0.3, as mentioned in the previous summaries, would generally be considered small to moderate. However, given the practical context of athletic performance and physical health, even small improvements can be deemed beneficial and meaningful, particularly if they lead to improved competitive performance or health outcomes.
Adaptations from Extended Training Periods (over 2 weeks)
Longer periods of supplementation tend to boost overall training effectiveness. This is achieved by enabling higher volumes of training, which, when combined with structured training programs, may lead to significant training improvement.
These improvements are likely driven by enhanced training consistency and intensity, supported by increased levels of PCr in muscles, and are observed both in individuals accustomed to resistance training and those who were initially inactive. For example, seasoned powerlifters who used Creatine noted more significant progress in their 3-rep max bench press and could complete more repetitions at 85% of their 3RM over 26 days than their placebo-taking counterparts. In a similar vein, recreational bodybuilders who supplemented with Creatine during a 5-week period, alongside resistance training, experienced greater increases in muscle (23).
May lead to increased muscle mass and lean body mass
There are numerous factors to consider when discussing supplementation and lean muscle growth, namely age, training status, gender, dietary intake, training volume to name a few. A superb review by Wu et al, 2021 aimed to investigate the effects of Creatine supplementation for muscle growth in various populations. A strict criteria was applied with 16 randomised controlled trials being selected from 2012 -2021 (24).
Three major themes related to muscle growth were derived from the review.
- Subjects of Creatine supplementation—muscle growth is more effective in healthy young subjects than others.
- Training of subjects—sufficient training is important in all populations.
- High-level evidence-based research on the efficacy and validity of Creatine supplementation in muscle growth for the elderly or patients with muscle-related diseases is lacking.
It is imperative you understand that resistance training and adequate protein intake are the key drivers for muscle growth. Creatine can support these but independent of them, it will not increase muscle growth.
May improve exercise capacity and endurance
As I have mentioned earlier in the article, oral supplementation with Creatine effectively raises intramuscular phosphoCreatine (PCr) levels, which are crucial for the ATP-PCr energy pathway that predominantly fuels ATP production during 0–30 second high-intensity activities. This substantial increase in PCr storage is a fundamental reason why Creatine is known to enhance performance in intermittent, high-intensity exercises. High-intensity activities that demand significant force output rely more on type II muscle fibers, which naturally store more PCr than the oxidative type I fibers.
The improvement in performance can be attributed to a greater initial PCr concentration at the start of an exercise and a more efficient PCr regeneration during the rest intervals of intermittent anaerobic exercises. Consequently, when Creatine is supplemented, the availability of PCr is better maintained throughout successive exercise sets, helping to mitigate power output reduction and fatigue.
So we know that Creatine supplementation may enhance performance in short, intense bouts of exercise, but its effects are less pronounced for prolonged, lower intensity endurance activities.
For instance, a study involving cyclists found that while Creatine significantly boosted high-intensity exercise performance, it had little impact on lower intensity efforts (25).
A comprehensive analysis of existing research confirmed that Creatine offers considerable benefits for activities of short duration but provides limited advantages for sustained endurance exercises (26). This seems to be because endurance activities typically require sustained energy output at lower intensities, which depends less on the rapid regeneration of ATP, a process where Creatine plays a key role (27).
Nonetheless, Creatine might indirectly benefit endurance by enhancing the quality and intensity of training sessions as a well structured training endurance programme will still have resistance based training in some fashion.
Thus, while Creatine's direct impact on endurance activities may be minimal, its ability to augment high-intensity training elements could offer advantages for endurance athletes, particularly those incorporating sprints, intervals, or strength exercises into their training and races.
This is what a 2023 review of Creatine on endurance reported. Here is what the authors concluded.
“Overall, Creatine supplementation increases time to exhaustion during high-intensity endurance activities, likely due to increasing anaerobic work capacity. In terms of time trial performances, results are mixed; however, Creatine supplementation appears to be more effective at improving performances that require multiple surges in intensity and/or during end spurts, which are often key race-defining moments” (28).
May aid recovery and reduce muscle damage
The term recovery is often contextual in nature and typically pertains to either physiological, subjective, or performance-based parameters. When most people speak of improving recovery it is in relation to mitigating the loss of force production, reducing muscle damage, lowering soreness, and modulating inflammation.
Creatine may be of benefit in relation to facilitating recovery, particularly in terms of physical performance, after periods of intense exercise. It has also been reported to lessen the inflammatory response after exercise, which in turn may attenuate indicators of muscle damage and alleviate muscle soreness.
To preface this section it seems most of the research is done on short time frames of around 5-6 days and the dosing is 20g per day of Creatine. As you will see in the section on dosing this is not needed but there is little data on muscle damage and recovery over longer periods of time and at lower doses.
However, Wang et al. 2018 indicated that a 4-week period of Creatine supplementation (20 g/day for 6 days followed by 2 g/day for 22 days) in conjunction with a complex training regimen reduced the post-exercise increase in Creatine kinase compared to a placebo group (29). This equates to 164g and if this is divided over the 28 days it equals 5.85g per day, which is similar to a normal daily dose.
Furthermore, Rosene et al. 2009 reported a higher level of maximal isometric force production in the days following a bout of eccentric leg extensions, a type of exercise known to instigate muscle damage, in those supplementing with Creatine after a maintenance dosing protocol, but not after an acute loading dose protocol (30).
In a similar vein to this Cooke et al. 2009 reported a 10% greater isokinetic and isometric (21% higher) knee extension strength in a group that supplemented with Creatine (0.3 g/kg body weight × 5 days) following a bout of eccentric-only repetitions using 120% of the subjects’ 1RM on leg press, leg extension, and leg flexion exercise machines. Lower Creatine kinase levels (a common marker of muscle damage) were observed at 48, 72, and 96 h, and 7 days, following the exercise in the Creatine supplementation group. However, there are numerous studies that suggest Creatine supplementation did not appear to affect markers of muscle damage, soreness, strength deficits, or fatigue following exercise (31,32,33).
What we do see from the research is that Creatine supplementation seems to have no negative effects on muscle recovery. It is not the primary reason you should be supplementing with Creatine but it may infer an added benefit in some scenarios.
Where to get Creatine Monohydrate
Creatine is naturally produced and stored in muscle tissue and can be found in various animal products, including red meat, poultry, and fish. Here are some foods high in Creatine:
- Red Meat: Beef, veal, lamb, venison, and rabbit are excellent sources of Creatine.
- Fish and Seafood: Herring, salmon, and tuna are rich in natural Creatine.
- Poultry: Chicken, turkey, fowl, and duck also contain Creatine, although in smaller amounts than red meat and fish.
- Pork: Pork is another good source of Creatine.
- Dairy Products: Milk, yoghurt, and cheese contain smaller amounts of Creatine compared to meat but still contribute to overall intake.
For individuals following a vegan or vegetarian diet, it may be challenging to obtain sufficient Creatine solely from food sources due to its predominantly animal-based nature. However, plant-based sources like pumpkin seeds, sesame seeds, walnuts, almonds, watercress, spinach, and spirulina provide amino acids necessary for Creatine synthesis.
For vegetarians or vegans, supplementing with Creatine may be beneficial due to the limited dietary intake of Creatine from plant sources (34). While Creatine is naturally synthesised in the body using amino acids like glycine, arginine, and methionine, individuals on a vegetarian or vegan diet may have lower baseline muscle Creatine levels. Studies suggest that vegetarians can respond even better to Creatine supplementation than omnivores, leading to greater increases in Creatine stores, muscle strength, and overall performance (35).
A superb review titled Benefits of Creatine Supplementation for Vegetarians Compared to Omnivorous Athletes: A Systematic Review. The authors concluded that overall, it appears vegetarian athletes are likely to benefit from Creatine supplementation (35).
As you can see from the image below, dietary choices and whether you supplement or not can dictate overall Creatine levels.
Approximate muscle total Creatine levels in mmol/kg dry weight muscle reported in the literature for vegetarians, individuals following a normal diet, and in response to Creatine loading with or without carbohydrate (CHO) or CHO and protein (PRO). From Kreider and Jung.
Creatine Monohydrate Dosage & How to Take
Before I get into the details of loading phases and whether you need to cycle it, I want to present some data to say that after over 20 years of research which demonstrates no adverse effects from recommended dosages of Creatine supplements on kidney health, unfortunately, specific concerns persists with regard to kidney and liver health. While the origin is unknown, the connection between Creatine supplementation and kidney damage/renal dysfunction seems to be due to a poor understanding of the Creatine / Creatine metabolic pathway. Antonio et al, 2021 wrote a superb paper outlining the common misconceptions and concerns around Creatine and their conclusion on Creatine’s effects on kidney function states -
“In summary, research indicates that Creatine supplementation, when ingested at recommended dosages, does not result in kidney damage and/or renal dysfunction in healthy individuals” (36)
How much Creatine one needs to see a positive response can vary based on dietary habits, age and training type. If you have an extremely high intake of red meat you may see fewer benefits to Creatine supplementation as you already have a higher intake.
A general consensus from the research suggests a range of 3-5g per day for at least 2-4 weeks is required to see a benefit, but some people may want to utilise a loading phase to saturate Creatine stores at a quicker rate.
Creatine loading involves taking a larger amount of Creatine for the first few days of supplementation (usually 20g per day or 0.3 grams per kilogram of bodyweight per day for 5–7 days) before reducing the daily dose to “maintenance” levels (at least 0.03 g/kg of bodyweight). The more commonly used strategy involves simply taking a smaller dose (usually 3–5 g) of Creatine every day.
Loading phases can be used if you have not supplemented with Creatine before or have taken a break and have an event that you want to elevate Creatine stores for.
Although both loading and non-loading strategies increase muscle Creatine stores, Creatine loading saturates muscles with Creatine within the first week of supplementation, while non-loading takes around 4 weeks (37)
Creatine loading strategies - from Antonio et al, 2021
So, in short: you do not need to load Creatine. However, Creatine loading will lead to slightly quicker benefits than non-loading, with the downside being a potentially greater risk of experiencing digestive discomfort during the loading phase.
Do you need to cycle Creatine monohydrate?
As mentioned earlier Creatine is safe to take at the recommended dosages for extended periods of time (1) but cycling off it can be something to consider. The washout period for Creatine stores to return to baseline are around 4 weeks (38). Practically applying this it could be that you stop taking during times such as holidays, Christmas or lower training blocks.
Conclusion
Creatine is one of the most researched supplements with strong evidence that suggests it may help with exercise performance, strength, recovery and hypertrophy. The recommendation is to take 3-5g daily for at least 2-4 weeks to see benefits and there is no need to cycle it. Creatine monohydrate is the preferred form to take with other variations showing no further benefit.
It would be highly recommended to consult a healthcare professional before starting any supplementation regime. If you are someone who is training regularly Creatine may be something worth considering to enhance your performance.
Frequently Asked Questions (FAQs)
Is Creatine Monohydrate safe for long-term use?
Over 1,000 studies have been conducted on Creatine supplementation, demonstrating its safety and efficacy. Studies have consistently shown that Creatine supplementation, even at high doses for up to 5 years, poses no significant health risks in healthy and diseased populations (1). The International Society of Sports Nutrition supports the safety and efficacy of creatine monohydrate supplementation, emphasising its well-tolerated nature across various populations (1).
While creatine is generally safe, high doses may lead to side effects like dehydration, upset stomach, and muscle cramps. Individuals with kidney disease, high blood pressure, or liver disease should avoid Creatine supplementation. It is advisable to consult a healthcare provider or GP before starting Creatine intake, especially for those with existing medical conditions (37)
Can Creatine Monohydrate cause weight gain?
Here are the two primary reasons you may see a jump on the scales when supplementing with Creatine
.
- Water Retention: Creatine supplementation can cause rapid water weight gain as it draws water into muscle cells, leading to a temporary increase in body weight. This water retention is localised to the muscles and can give the appearance of increased muscle size and fullness, contributing to overall weight gain (39).
- Lean Muscle Mass: While creatine may initially cause water weight gain, research indicates that it is an effective supplement for enhancing endurance and strength. Over time, Creatine supplementation can support muscle growth and performance improvements, which may contribute to overall weight gain.
Does Creatine Monohydrate require a loading phase?
In short, no, a loading phase is not needed if you plan to take Creatine consistently. Creatine loading involves taking a larger amount of Creatine for the first few days of supplementation (usually 20g per day or 0.3 grams per kilogram of bodyweight per day for 5–7 days) before reducing the daily dose to “maintenance” levels (at least 0.03 g/kg of bodyweight). The more commonly used strategy involves simply taking a smaller dose (usually 3–5 g) of Creatine every day.
Loading phases can be used if you have not supplemented with Creatine before or have taken a break and have an event that you want to elevate Creatine stores for.
Although both loading and non-loading strategies increase muscle Creatine stores, Creatine loading saturates muscles with Creatine within the first week of supplementation, while non-loading takes around 4 weeks (37)
Should I take Creatine when dieting?
With all diets the goal is to lose the correct type of weight (fat not muscle), and with Creatine potentially supporting the growth and maintenance of lean muscle it may be a sensible addition to your regime. Research has shown that mean percent body fat and caloric intake was not affected by creatine supplementation. Therefore any weight gain in lieu of Creatine supplementation may in part be due to water retention (39).
Is Creatine Monohydrate legal in sports?
Creatine is legal for use in sports and is not prohibited by organisations like WADA, the International Olympic Committee (IOC). Professional athletes, are allowed to use Creatine supplements as they are not considered banned substances. My suggestion would still be to check where you are getting your Creatine from and ensure that they are part of the Informed Sport Manufacturer program or that it has been banned substance tested. Be very cautious with products that use Creatine in a blend as there may be other ingredients that are not legal. MARCHON Creatine is produced in a facility that is part of the Informed Sport Manufacturer program.
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