Should you be taking creatine?
Swedish researcher Eric Hultman and colleagues pioneered the investigation of creatine to improve human athletic performance back in the 1980s3. A growing body of research combined with pro athletes touting their creatine use to aid training sparked the growth of commercially available creatine supplements3. As of 2013, over 2 million kilograms of creatine are consumed per year3, and as of 2017, creatine accounted for over $400 million per year in sales revenues1.
Though creatine is found in foods (mainly meat) and can be synthesized naturally in the body, our creatine stores are not saturated without supplementation1,2,3. Though some supplement companies would like you to believe otherwise, creatine monohydrate is highly bioavailable3. However, creatine does seem to be absorbed more readily when ingested in a solution form or in it’s naturally occurring state from meat compared to solid suspension (powder quickly mixed into a liquid) or capsule form3.
Creatine is the primary fuel for high-intensity short-duration exercise (like powerlifting) via the phosphocreatine (PCr) metabolic pathway1,2,3. This pathway provides large amounts of energy in the form of ATP quickly, but is depleted within 10-20 seconds of high-intensity activity1,2,3. PCr reserves are replenished by the slower oxidative metabolic pathways3, so very high-intensity activities cannot be sustained. In other words, performance decreases as the slower metabolic pathways begin to take over and the rate of muscular contraction can no longer be maintained, thus illustrating the draw of supplementing creatine to improve performance. Under normal circumstances, creatine stores are not fully saturated; supplementing creatine allows stores to be maximized3.
Anaerobic activities which require short periods of rapid force development are most likely to benefit from creatine supplementation 1,2,3. This includes strength sports like powerlifting and weightlifting, football, sprinting and field events, and many more. On average, creatine induces 5-15% improvements in maximal effort muscle contractions, maximal power/strength performance, and repetitive effort sprint performance2,3. 1-5% increases have also been observed in single sprint performances3. Creatine supplementation potentially decreases recovery time between high-intensity bouts, such as repeated sprints3. Additionally, creatine can act as a buffer by consuming H+ ions that would otherwise interfere with myosin and actin bonding (decreasing muscle force production)1,2,3. In this capacity, having free creatine available in the muscle tissue potentially offers exercise intensity sustainability.
In short term studies, the effects of creatine supplementation are predominantly performance-based, while in long term studies, physique effects are more apparent1,2,3. In fact, subjects taking creatine in 4-12 week studies have gained double the amount of lean mass compared to subjects ingesting a placebo3. Creatine acts as an osmolyte, drawing fluid into the cell and serving as an agonist to protein synthesis3. Exercising individuals supplementing with creatine express significantly more insulin-like growth factor-1, a hormone that dictates the hypertrophy response to exercise, than individuals who do not supplement3.
To improve anaerobic performance, athletes can supplement with a maintenance dose of 3-6 grams of creatine monohydrate daily1,2,3. Those who are on a short timeline may choose to implement a loading period of up to 20-25 grams per day (divided into several doses per day) before adjusting to daily maintenance doses of 3-5 grams per day 1,2,3. While loading may decrease the time needed to saturate creatine stores, it is not necessary for many athletes, and stores will be saturated with the lower daily dose after approximately 28 days1,3. To enhance tissue uptake of creatine, co-ingesting with 50-80 grams of carbohydrates and 30-50 grams of protein has shown improved absorption when compared to creatine ingestion alone2,3. This is likely due to the insulin and protein synthesis responses2,3, and taking creatine post-exercise with a meal may be a good way to increase absorption.
In terms of increasing lean body mass and high-intensity exercise performance, creatine is the most effective and research-validated supplement available 1,2,3. There have been over 1000 studies conducted on creatine and its effects on the body. Though negative effects on kidneys, dehydration, and muscle cramps are often cited as dangers of creatine supplementation, these concerns are isolated to individuals with pre-existing conditions, and have not been validated in research on otherwise healthy individuals1,3. Furthermore, creatine has actually been shown to benefit hydration by increasing total body water3, though as with the addition of any new supplement or medication, extra precautions should be taken. The only “negative” side effect shown to date is weight gain, primarily due t