Creatine is a natural substance that is mainly found in muscle cells to help produce energy during high-intensity exercise.
Although some amount of creatine is synthesized within the body from other substances such as glycine and arginine, many athletes now choose to supplement with additional creatine to further increase their stores.
In fact, creatine is one of the most well-studied sport supplements of the last decade and is extremely prevalent in bodybuilding and fitness communities.
The main reason why people take creatine supplements is to gain muscle, improve strength, and enhance performance.
Benefits Of Creatine Supplementation
Increased Strength And Power
Creatine supplementation increases muscle stores of creatine. This is a form of stored of energy in muscle cells and aids the production of a high-energy molecule called ATP during intense exercise.
ATP is often called the bodies “energy currency”. Therefore, a supplement like creatine that can increase ATP production may benefit athletic performance.
Under normal circumstances, ATP stores become depleted after 8-10 seconds of very high-intensity exercise. The idea is that elevated creatine stores allow more ATP to be produced, which can result in a further maintenance of intense activity by 1-2 seconds.
Research confirms that supplementation effectively achieves this, with just 6 days of creatine loading increasing muscle creatine concentrations by ~20% .
The exact increase in creatine stores from creatine supplementation depends on several factors such as baseline creatine concentrations and dietary creatine intake .
However, even more drastic results have been found, such as creatine supplementation for 9 weeks increasing bench press strength by ~10%, and peak power by ~20%, in division 1 college football players .
Increased Muscle Growth
Creatine is probably the most proven and effective dietary supplement for adding muscle mass.
This is supported by a review of ~250 studies that compared the most popular muscle building supplements .
A similar review reported that creatine supplementation is able to increase lean body mass by ~2%, and decrease body fat by ~3%, when taken for extended periods .
The increase in muscle mass is likely as a secondary effect from the long-term benefit of creatine in improving strength, power, and work volume. Given, improvements in these areas will enable an athlete to induce more tension on a muscle within a training session from an enhanced ability to perform more exercises, repetitions, and lift heavier weights .
Other potential mechanisms by which creatine may increase muscle mass are:
- Improved cell signaling:Can increase satellite cell signaling, which aids muscle repair and new muscle growth .
- Lower myostatin levels:Elevated levels of the protein myostatin can slow or totally inhibit new muscle growth. Supplementing with creatine can reduce these levels, increasing muscle growth potential .
- Raised anabolic hormones:Studies note a rise in hormones, such as IGF-1, after taking creatine 
Different Forms Of Creatine Supplements
This is the most common and well-research form of creatine supplements, made up of a creatine molecule and a water molecule (monohydrate form is ~90% creatine by weight).
Creatine monohydrate is sometimes micronized to improve water solubility. In theory, better water solubility could improve the ability to absorb creatine.
This form has shown to be able to fully saturate a muscle cell with creatine . In other words, provided the frequency and dose of creatine supplementation follows normal recommendations (~5 grams per day), creatine monohydrate is able to achieve maximum results by optimizing creatine concentrations within muscle cells.
Due to this, other forms of creatine are only able to match the effectiveness of creatine monohydrate (at best!). Newer forms of creatine need to be compared to creatine monohydrate before they can be recommended .
Creatine hydrochloride (HCl) has recently gained a lot of popularity with some supplement companies and users.
It is advertised to be a more soluble form of creatine that can potentially be absorbed better than creatine monohydrate.
Limited research supports this statement, with creatine hydrochloride being ~40 times more soluble in water than creatine monohydrate . Based on this superior solubility in water, it has been speculated that it requires a lower dose compared to creatine monohydrate in order to achieve the same effect.
Other evidence also suggests that creatine HCl might reduce side effects such as an upset stomach because it has a greater permeability in the intestinal tract compared to creatine monohydrate .
Proposers of creatine HCL propose that the combination of greater water solubility, and permeability in the gut, could decrease the amount of creatine needed to fill the muscle, resulting in lower rates of creatine excretion, and therefore less gastrointestinal discomfort.
There is a current lack of evidence to analyze the differences that the two forms of creatine have upon impacting performance. Based on the mechanistic understanding of the compound, it is unlikely that there will be any major differences.
However, one study did suggest that creatine HCl improved body composition more than creatine monohydrate after 4 weeks of supplementation in recreational weightlifters – although this may have just been a result of increased water retention from creatine monohydrate .
More comparative studies are needed for a better assessment of the various types of creatine supplements.
Is Creatine Hydrochloride Safer Than Creatine Monohydrate?
Overall, creatine monohydrate has an outstanding safety profile .
However, some reported side effects are weight gain from excess water retention , and stomach issues from gastrointestinal stress . These side effects seem to be more prevalent as creatine dosages increase .
As creatine HCl requires a reduced dosage (~1.5 grams per day) in order to achieve the same, or at least a similar effect, it could be a good alternative to reduce water retention and stomach issues in susceptible individuals.
However, the prevalence of side effects of creatine HCl are not yet known and are currently only based on speculation.
Creatine supplementation is well understood to improve strength, power, and athletic performance.
The most common form is creatine monohydrate, which can provide maximal benefits by fully saturating creatine stores within muscle cells. However, some people may experience stomach issues or water retention with this form of creatine.
Creatine HCl offers a different supplemental form that is better absorbed in water and requires a reduced dosage to achieve a similar result. This could potentially reduce the likelihood of side effects.
In terms of performance benefits, neither form of creatine has shown superior results, but more comparative research is needed in this area.