What is Creatine?
- Creatine is a nitrogenous organic acid that occurs naturally in vertebrates, it increases the production of body’s energy currency ATP, especially in skeletal muscles.
- Human body synthesizes creatine in kidneys and liver from amino acids glycine and arginine, it is transported to tissues with high energy demand, like brain and muscles via blood. It is stored in skeletal muscles in the form of “Phosphocreatine” which is capable of generating and replenishing ATP at a very fast rate.1
How it Works
- Creatine is responsible for the improvement of muscle function and energy metabolism. There is strong scientific evidence available showing an increase in muscle power and force after creatine intake, creatine consumption also reduces muscle fatigue in repeated activities and causes a significant increase in muscle mass. It improves exercise performance and muscle grown by following mechanisms of action 2.
- Energy Metabolism: Adenosine triphosphate (ATP) concentrations maintain physiological processes and protect tissue from hypoxia-induced damage. Creatine is involved in ATP production through its involvement in phosphocreatine energy system.
- Protein Synthesis: Creatine increases protein synthesis and reduces protein breakdown, resulting in increased muscle mass. It is also a powerful osmotic agent and draws water inside the cells resulting in increased cell hydration and causing swelling which results in increased anabolic activity.
- Membrane Stabilization: Creatine acts as a membrane stabilizer and prevents tissue damage.
- There is scientific evidence that creatine use can increase maximum power and performance in high intensity anaerobic workouts. It increases the amount of fast energy stored in muscles, draws more water into muscle cells, and also increase the levels of Insulin Like Growth Factor 1, IGF-1, which is critical for muscle growth3.
- The body is capable of producing creatine, meat, eggs and fish are rich sources of creatine. Around 2 g of Creatine is required for normal day to day activities. The average human body stores around 120-140 g of creatine, mainly in skeletal muscles (95%). 60-70% of stored creatine is in the form of phosphocreatine and is stored in fast twitch fibers4. Excess creatine is eliminated by the kidneys.
- There are many different forms of creatine supplements available on the market. The water soluble form “creatine monohydrate” is the most widely used and easily available.
Creatine monohydrate is generally started with a loading dose followed by a maintenance regimen. The recommended loading protocols suggest taking 0.3 gram of creatine monohydrate per kilogram of bodyweight per day for the first 5–7 days, followed by a maintenance dose of 0.03 g of creatine per kilogram of body weight per day5.
Other available forms are Creatine ethyl ester and Micronized creatine, they are also widely used.
Does Creatine increase the muscle creatine content?
- Creatine supplements can increase the levels of muscle phosphocreatine content by 6-16%4. A scientific study conducted in 2011 concluded that taking 20g of creatine for a period of 10 days was sufficient to increase muscular phosphocreatine concentrations as well as power output in healthy adult males, while the effects were not observed in the group taking placebo. No significant change in body weight was obsereved6.
Another study was conducted on patients having Duchene muscular dystrophy. This randomized, placebo-controlled single blinded study was carried out to evaluate the effect of oral creatine supplementation on cellular energy production mechanism. The effects were evaluated by manual muscle test (MMT) score and functional status of the patients. Eighteen patients who received 5 grams of creatine monohydrate for 8 weeks showed significant improvement due to increased muscle phosphocreatine levels.
The levels of phosphorus metabolite ratios were also determined before the treatment to establish the base line. These were measured from the right calf muscles using phosphorus magnetic resonance spectroscopy. These measurements were also taken for the normal subjects to establish control levels. A Significant increase in metabolite ratio was observed in patients taking creatine, while the group taking placebo showed no marked increase in phosphorous metabolites levels. This confirmed the theory that supplementation with creatine increases muscle phosphocreatine levels7.
Creatine ethyl ester is one of the supplements available in the market. A double blind placebo controlled study was conducted on 30 trained athletes for seven weeks, to assess and compare the effects of creatine monohydrate and creatine ethyl ester on body composition, muscle mass, muscle strength and power, serum and muscle creatine level and serum creatinine levels.
Participants were randomly assigned to a maltodextrose placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were given in oral form at a dose of 0.30 grams per kg fat-free body mass (approximately 20 g/day) as loading dose for the first five days followed by a maintenance dose of 0.075 grams per kg fat free mass (approximately 5 g/day) for the next 42 days.
The results of this study showed significantly higher serum creatine concentrations in the group taking placebo as compared to both supplements. Serum creatinine levels were greater in the group taking creatine ethyl ester, as compared to the group taking placebo, and increased at days 6, 27, and 48.
Total muscle creatine content was significantly higher in the group taking creatine in both forms, and was significantly higher than the placebo group. Marked changes were observed in the body composition, body water content, muscle strength and power of the group taking creatine supplements. In conclusion creatine monohydrate was more effective in increasing muscle and serum creatine levels as compared to creatine ethyl ester and placebo. The results clearly confirmed that creatine supplementation results in improved body composition, and increases muscle mass, strength, and power 8.
- Creatine supplements should be taken with a lot of water, if not taken with sufficient amount of water it can cause stomach cramping. Taking large doses of creatine can lead to nausea and/or diarrhea. Ideally the total daily dose should be spread out over the day and taken with meals.
- Creatine is a relatively safe supplement but people with kidney disease, liver disease or diabetes should avoid it.
- Creatine plays a vital role in body’s energy system; it is stored in muscle cells as creatine phosphate which can rapidly produce energy in the form of ATP to support cellular function. Oral supplements lead to an increase in muscle creatine and energy levels. It is well known for its performance-enhancing and neuro-protective properties and is remarkably safe for most people.