Intro to Creatine
What is creatine?
Of the many supplements available for improving exercise performance, creatine is one of the most commonly used. Creatine is an organic compound found in foods such as milk and red meat which is primarily stored in the body in muscle. Its purpose is to replenish energy as it gets consumed (for example, during a workout or when playing sports). Since it increases energy stores during energetic demand, the goal of creatine supplementation is to delay muscle fatigue and perpetuate optimal performance.
How does creatine work?
One of the most prominent molecules used by our bodies for energy is ATP (adenosine tri-phosphate, three "phosphate" groups on the molecule). The use of ATP ranges from facilitating basic cellular activities, to promoting muscle contraction. A molecule of ATP provides energy by the removal of phosphate groups. After doing so, ATP assumes an energy-exhausted state known as ADP (adenosine di-phosphate, two "phosphate" groups on the molecule), or in some cases, AMP (adenosine mono-phosphate, one "phosphate" group on the molecule) [1]. ADP and AMP may be reverted back to ATP by different means which allows reusing of a replenished ATP molecule for energy. Creatine carries phosphate groups and works to convert ADP to ATP [2]. Because we use ATP during weightlifting, cardio, or sports, it can be expected that creatine plays an important role in high intensity activities such as maximal effort weightlifting or sprinting.
Studies on Creatine
Studies have evaluated the effects of creatine supplementation on various exercises, including, but not limited to, weightlifting and cycling. Results showed a noticeable increase in power, and muscle activity before fatigue [3]. Furthermore, the following table from the Journal of the International Society of Sports Nutrition summarizes the benefits of creatine, from multiple studies:
Some studies also determined that ingesting carbs and/or proteins along with creatine increases its retention [5, 6]. Interestingly, the effect of creatine on muscle soreness via inflammation was investigated, and results showed decreases in inflammatory proteins (TNFα, prostaglandin E2) [7].
Is it safe?
As reported in the Journal of International Society of Sports Nutrition [8], several studies concluded that creatine is very safe! There are no real harmful side effects of taking creatine, only benefits. Many complications associated with creatine supplementation reported by peoples' personal experiences have been deunked. In controlled clinical studies, no statistical evidence exists to connect creatine to injury, dehydration, or intestinal upset.
Personally, I'd recommend creatine to those that are serious about their exercise. It's not a magic compound that will double your lifts or halve your mile time, but it's certainly beneficial for those who work hard and long-term to achieve their respective fitness goals. There are some side effects that can result from taking creatine, but that can mostly be attributed to another factor(s) that is specific to the individual. In such events, or even prior to taking creatine, consult your doctor. Whether it's good form or good supplementation, safety first!
PS: For a thorough breakdown of creatine, I highly suggest reading the article I mentioned by the Journal of International Society of Sports Nutrition (reference 8).
References
1. Richter EA., Ruderman NB., "AMPK and the biochemistry of exercise: Implications for human health and disease," Biochem J. 2009 Mar. 1: 418(2): 261-275.
2. Korge P., Campbell KB., "Local ATP regeneration is important for sarcoplasmic reticulum Ca2+ pump function," Am J Physiol. 1994 Aug;267(2 Pt 1): C357-66.
3. Kreider RB., "Effects of creatine supplementation on performance and training adaptations," Mol Cell Biochem. 2003 Feb;244(1-2):89-94.
4. Hultman E. et al., "Muscle creatine loading in men," J Appl Physiol. 1996 Jul;81(1):232-7.
5. Green AL. et al., "Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans," Am J Physiol. 1996 Nov;271(5 Pt 1):E821-6.
6. Steenage GR., Simpson EJ., Greenhaff PL., "Protein- and carbohydrate-induced augmentation of whole body creatine retention in humans," J Appl Physiol (1985). 2000 Sep;89(3):1165-71.
7. Santos RV. et al., "The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race," Life Sci. 2004 Sep3;75(16):1917-24.
8. Kreider KB. et al., "International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport and medicine," Journal of the International Society of Sports Nutrition. 2017 14:18.
Of the many supplements available for improving exercise performance, creatine is one of the most commonly used. Creatine is an organic compound found in foods such as milk and red meat which is primarily stored in the body in muscle. Its purpose is to replenish energy as it gets consumed (for example, during a workout or when playing sports). Since it increases energy stores during energetic demand, the goal of creatine supplementation is to delay muscle fatigue and perpetuate optimal performance.
How does creatine work?
One of the most prominent molecules used by our bodies for energy is ATP (adenosine tri-phosphate, three "phosphate" groups on the molecule). The use of ATP ranges from facilitating basic cellular activities, to promoting muscle contraction. A molecule of ATP provides energy by the removal of phosphate groups. After doing so, ATP assumes an energy-exhausted state known as ADP (adenosine di-phosphate, two "phosphate" groups on the molecule), or in some cases, AMP (adenosine mono-phosphate, one "phosphate" group on the molecule) [1]. ADP and AMP may be reverted back to ATP by different means which allows reusing of a replenished ATP molecule for energy. Creatine carries phosphate groups and works to convert ADP to ATP [2]. Because we use ATP during weightlifting, cardio, or sports, it can be expected that creatine plays an important role in high intensity activities such as maximal effort weightlifting or sprinting.
Studies on Creatine
Studies have evaluated the effects of creatine supplementation on various exercises, including, but not limited to, weightlifting and cycling. Results showed a noticeable increase in power, and muscle activity before fatigue [3]. Furthermore, the following table from the Journal of the International Society of Sports Nutrition summarizes the benefits of creatine, from multiple studies:
Kreider et al., "International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport and medicine," 2017 14:18.
Is it safe?
As reported in the Journal of International Society of Sports Nutrition [8], several studies concluded that creatine is very safe! There are no real harmful side effects of taking creatine, only benefits. Many complications associated with creatine supplementation reported by peoples' personal experiences have been deunked. In controlled clinical studies, no statistical evidence exists to connect creatine to injury, dehydration, or intestinal upset.
Personally, I'd recommend creatine to those that are serious about their exercise. It's not a magic compound that will double your lifts or halve your mile time, but it's certainly beneficial for those who work hard and long-term to achieve their respective fitness goals. There are some side effects that can result from taking creatine, but that can mostly be attributed to another factor(s) that is specific to the individual. In such events, or even prior to taking creatine, consult your doctor. Whether it's good form or good supplementation, safety first!
PS: For a thorough breakdown of creatine, I highly suggest reading the article I mentioned by the Journal of International Society of Sports Nutrition (reference 8).
References
1. Richter EA., Ruderman NB., "AMPK and the biochemistry of exercise: Implications for human health and disease," Biochem J. 2009 Mar. 1: 418(2): 261-275.
2. Korge P., Campbell KB., "Local ATP regeneration is important for sarcoplasmic reticulum Ca2+ pump function," Am J Physiol. 1994 Aug;267(2 Pt 1): C357-66.
3. Kreider RB., "Effects of creatine supplementation on performance and training adaptations," Mol Cell Biochem. 2003 Feb;244(1-2):89-94.
4. Hultman E. et al., "Muscle creatine loading in men," J Appl Physiol. 1996 Jul;81(1):232-7.
5. Green AL. et al., "Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans," Am J Physiol. 1996 Nov;271(5 Pt 1):E821-6.
6. Steenage GR., Simpson EJ., Greenhaff PL., "Protein- and carbohydrate-induced augmentation of whole body creatine retention in humans," J Appl Physiol (1985). 2000 Sep;89(3):1165-71.
7. Santos RV. et al., "The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race," Life Sci. 2004 Sep3;75(16):1917-24.
8. Kreider KB. et al., "International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport and medicine," Journal of the International Society of Sports Nutrition. 2017 14:18.
What are the side effects of creatine? And what are the benefits? Are they actually clinically significant? Especially for the more average joe versus an athlete..
ReplyDelete"Short-term creatine supplementation has been reported to improve maximal power/strength (5-15%), work performed during sets of maximal effort muscle contractions (5-15%), single-effort sprint performance (1-5%), and work performed during repetitive sprint performance (5-15%)."
ReplyDelete- Kreider KB (Mol Cell Biochem. 2003 Feb;244(1-2):89-94.)
"The addition of creatine to drop-set resistance training augments the gains in muscle mass from resistance training alone. Creatine is more effective in untrained aging males compared to untrained aging females."
- Johannsmeyer S. et al. (Exp Gerontol. 2016 Oct;83:112-9.)
Reported side effects are merely anecdotal, however, studies show no statistically significant side effects.