Creatine is the most effective supplement for increasing muscle mass and strength (1).
It is a fundamental supplement in the bodybuilding and fitness communities (2).
Research shows supplementing with creatine can double your strength and lean muscle gains when compared to training alone (3).
This article takes a detailed look at the effects of creatine on strength, power and muscle mass.
Adenosine triphosphate (ATP) is the most basic form of energy in your body's cells. It plays a fundamental role in metabolism and muscle function.
Unfortunately, you can only store enough ATP for 8–10 seconds of high-intensity exercise. After this, your body must produce new ATP to match the demands of the activity (4).
Performing exercise at maximum intensity requires more ATP per second than your body can produce (5).
This is one reason why you can only sprint at full speed for a few seconds. Your body's ATP energy simply runs out.
Creatine supplements increase your body's stores of phosphocreatine, which is used to produce new ATP during high-intensity exercise (5).
The extra creatine in your muscles can then be used for ATP production, providing a small amount of extra energy before fatigue sets in.
Bottom Line: Creatine may provide additional ATP energy, which is vital for maximal power and strength-based activities.
In addition to creatine's role in ATP energy production, it may also improve the function of your muscle cells in other ways (7).
It may also increase IGF-1, a key hormone for muscle growth (9).
Creatine may also help you reduce muscle breakdown and retain muscle during exercise. This may result in a greater amount of muscle in the long-term (11).
Another long-term benefit of creatine is the ability to perform more exercises or repetitions and lift heavier weights per training session (12).
Although this may not make a difference in one week, the total amount of weight lifted is a key factor in long-term muscle growth (12).
The graph below demonstrates the changes in size of different types of muscle fibers following creatine supplementation (13).
Bottom Line: Creatine can cause numerous changes within muscle cells, signaling your body to build new muscle proteins and increase muscle mass.
ATP energy is the main fuel source for high-intensity exercise.
Because creatine can increase phosphocreatine levels and therefore increase ATP energy production, it is one of the few supplements repeatedly proven to increase strength and power (14).
One 4-week study found a 17% improvement in cycling sprints, an 18-lb (8-kg) increase in bench press 1-rep max and 20% greater work load at a lower weight (3).
As you can see in the graph below, 10 weeks of taking creatine supplements also drastically increased half-squat power (15) .
Another study assessed both gym and fitness-based markers of power output.
After 9 weeks of taking creatine, Division 1 college football players witnessed the following improvements in performance (16):
- Bench press (1 rep max): 5.2% increase
- Power clean (1 rep max): 3.8% increase
- Squat (1 rep max): 8.7% increase
- High-intensity anaerobic peak power: 19.6% increase
- High-intensity anaerobic capacity: 18.4% increase
Most of the studies on creatine have found positive effects. One large review found a 5% average improvement in strength and power (17).
Bottom Line: Creatine improves numerous aspects of strength and power. The average increase may be around 5%.
There are only a few legal supplements that can directly add muscle mass when combined with exercise (14).
A review of 250 studies compared the most popular muscle building supplements, as shown in the graph below. Creatine provided the greatest benefit of all of them (14).
One 8-week study found that creatine increased muscle mass when added to an exercise regimen. Strength on the bench press was improved, along with a reduction in myostatin, which is a protein that inhibits muscle cell growth (18).
What's more, creatine has benefits for both beginners and more advanced weight lifters.
One study among well-trained athletes found that creatine added 5.7 lbs (2.6 kg) of muscle mass, 24 lbs (11 kg) to the bicep curl and 70 lbs (32 kg) to the leg press (1 rep max) (19).
Research has shown creatine supplements can also help women to tone up or increase strength. One study in women found a 60% greater increase in lean mass compared to a group that only strength trained (20).
Additionally, a review of over 150 studies reported an average 2.2% increase in lean body mass and a 3.2% decrease in body fat for those taking creatine (21).
Bottom Line: Current research suggests that creatine, when combined with weight training, is the single most effective supplement for adding muscle mass.
Until more research has been conducted on these new versions, creatine monohydrate is likely the most effective and cheapest option available.
Most studies use a high-dose loading strategy, which can rapidly elevate your muscle creatine content. Although this is not necessary, it will help you reap the benefits of creatine after just a few days (1).
To load with creatine, take four 5-gram servings throughout the day for about 5-7 days. After that, take 3-5 grams per day to maintain your muscle creatine stores (1).
The benefits you receive from creatine also depend on your current creatine muscle stores. The graph below shows the varied pre and post supplement levels in 16 people (23).
Those with already high creatine stores may receive less or insignificant benefits from the extra supplements. However, those with low creatine stores may see big improvements (1).
Although long-term creatine supplementation is safe for healthy individuals, it may not be suitable for those with kidney problems or other related diseases (22).
Bottom Line: The most common dosage protocol is a 5-7 day loading phase with about 20 grams of creatine per day, split into 4 doses. This is followed with a 3-5 gram per day maintenance dose.
As with most supplements, research shows that a small percentage of people do not receive any benefit from using creatine.
It may be most beneficial for vegetarians, vegans and those who do not eat much animal protein.
And although creatine is the number one exercise supplement, it will only provide benefits if you consistently follow a sensible exercise and nutrition plan.
If you regularly weight train and are looking to add muscle, creatine supplements may provide faster results while improving gym performance.
Here is a very detailed article about creatine: Creatine 101 – What is it and What Does it do?