Creatine is one of the most popular and highly searched supplements used by bodybuilders and athletes. It is produced in our body and has an important role in rapid production of energy in the form of ATP. Creatine is considered as enhancer of physical performance and hence taken as a supplement. It is often used by athletes to build muscle mass and power.
What is creatine?
Creatine is also known as creatine monohydrate, a-methylguanidinoacetic acid or creatine 2- oxopropanoate. The three amino acids that make up the creatine molecule are arginine, glycine and methionine. Creatine monohydrate is the most effective and commonly used form in the supplementations.
In the body, it acts as reservoir of phosphate1 by storing phosphate groups in the form of phosphocreatine or creatine phosphate. It releases energy in stressful conditions and helps in the body’s cellular functions. This action is believed to be the reason for strength, provided by creatine supplementation. High levels of creatine are found in heart and skeletal muscle. Some foods such as eggs, fish or meat are also a good source of creatine.
Does creatine affect muscle growth and mass?
Creatine results in increase water retention in the muscle cell leading to their swelling. This has a positive effect on the cell growth as an increase in swelling causes activation of stress response proteins, thereby, influencing muscle protein synthesis that results in muscle growth. Further, all this leads to increase in size of the muscle cells. Hence, creatine supplementation can increase the muscle size independent of protein synthesis.
Retention of water is an important phenomenon that is associated with this supplementation. With every dose, retention increases and can even exceed five pounds with higher loading doses. This increase in water retention causes an increase in muscle cell diameter which increases the rate of muscle growth. Though water mass is different from muscle mass, both counts in the lean body mass.
Hence, with increase in total water in the muscle cell, lean mass also increases. A study showed an increase in diameter of type I, IIa and IIx fibers following intake of 20g creatine by 9, 5 and 4% respectively2. Hence, creatine causes increase in muscle weight without an increase in the fat weight.
Studies done to assess the effects of creatine on skeletal muscles and performance
Besides its effect on various body tissues, creatine has an important role in the skeletal system. Various studies have been done to show this effect of creatine on lean body mass.
A study was done on 27 healthy men taking creatine supplements for 9 weeks, followed by a thrice weekly exercise regimen. It found a great increase in the lean muscle mass and power. These changes in the body mass were found to be increased during the loading phase of supplementation and further increased during maintenance3.
A meta-analysis of 100 studies was done in 2003 which found large evidence in support of enhancing the effect of creatine phosphate on lean mass and power output. Also, these effects of creatine supplementation were found to be similar on both men and women and trained or untrained people.
A study was done in both males and females to find out the effects of creatine ingestion after exercise on muscle thickness. This study included untrained individuals from 18-44 years of age. Creatine was given at a dosage of 0.2g/kg body weight after training on one side of the body. Following a trial period of 6 weeks, it was found to show significant increase in hypertrophy on the trained limb in males supplemented with creatine. However, it didn’t have any significant effect on the female participants.
A trial done in 30 healthy untrained male volunteers showed an increase in fat free mass following ingestion of creatine for 28 days and 5 hours of resistance training.
The effects of oral creatine were studied on lean mass and serum myostatin. Creatine was given in standard loading and then maintenance for 8 weeks. The results showed 17% reduction in myostatin with increases in lean mass.
Role of creatine in certain disease conditions
To further view its role in lean mass, studies were done to study the effect of creatine in certain diseases.
A study was done in patients with myotonic dystrophy type I. 34 patients belonging to both genders were included in the study. Creatine in a dose of 5g/day was given for 4 months. The results didn’t show any increase in lean mass in both the sexes.
Role of creatine supplementation has been explored as a treatment in sarcopenia which is a condition where passive loss of lean mass occurs with aging4. Creatine helps in alleviating sarcopenia and its effects are more significant when supplemented with resistance training5.
Creatine is an important supplement that can help to increase the lean mass. A large number of studies have been done to prove this correlation. However, most of them have found only a minor relation between these two. Also, the effects were more or less similar in both the sexes.
assessing its effect on lean mass is its water retention properties which confound its true effects. Researchers also failed to find any direct effect of creatine on the muscle mass. Despite all these, its role in building the lean body mass cannot be ignored.
- Darrabie MD, et al AMPK and substrate availability regulate creatine transport in cultured cardiomyocytes . Am J Physiol Endocrinol Metab. (2011)
- Safdar A, et al Global and targeted gene expression and protein content in skeletal muscle of young men following short-term creatine monohydrate supplementation . Physiol Genomics. (2008)
- Kilduff LP, et al Effects of creatine on body composition and strength gains after 4 weeks of resistance training in previously nonresistance-trained humans . Int J Sport Nutr Exerc Metab. (2003)
- Morley JE, et al Nutritional recommendations for the management of sarcopenia . J Am Med Dir Assoc. (2010)
- Candow DG, Chilibeck PD Effect of creatine supplementation during resistance training on muscle accretion in the elderly . J Nutr Health Aging. (2007)