Creatine Monohydrate Loading: An Evidence-Based Analysis of Benefits, Risks, and Practical Recommendations
By Ciaran Fairman
March 15, 2021 • 3 min read
Creatine monohydrate stands as one of the most extensively studied ergogenic supplements available. Consistent supplementation has been shown to enhance training quality and work volume, thereby facilitating greater adaptations in muscular strength, power, and lean body mass.[1–3] Notably, however, controversy persists regarding the optimal dosing strategy—specifically, whether an initial loading phase is necessary to maximize benefits.
Endogenous Creatine Balance
Endogenously, the human body synthesizes approximately 1 gram of creatine daily. A diet rich in meat and fish contributes an additional ~1 gram per day. Conversely, creatine degradation to creatinine occurs at a rate of 2 grams per day.[4] Since daily synthesis and dietary intake align with its degradation rate, supplementation represents a viable strategy to augment intramuscular creatine stores.
Clearing Up the Confusion: Loading vs. Low-Dose Regimens
Regardless of whether a loading phase is employed or a low-dose regimen is followed, creatine supplementation consistently increases resting intramuscular creatine levels by 17–20 percent.[5] The primary distinction between dosing strategies lies in the rate at which these increases are achieved.
What Is Creatine Loading?
The term “creatine loading” refers to an initial period (5–7 days) of elevated dosing, followed by a lower “maintenance” dose. A standard protocol involves 20 grams per day—administered as four 5-gram doses—for one week, with a subsequent maintenance dose of 3–5 grams per day.[6] The loading phase is designed to rapidly saturate intramuscular creatine stores, while the maintenance phase preserves this saturation.
Loading vs. Low-Dose: A Comparative Analysis
In contrast, studies evaluating low-dose regimens (3–5 grams per day, no loading) have demonstrated equivalent increases in creatine stores after 28 days.[5] While loading accelerates the rate of store saturation, the difference in total creatine levels between loading and low-dose protocols becomes negligible after one month.
A Critical Limitation: Muscle Storage Capacity
Skeletal muscle has a finite capacity for creatine storage. With a 20-gram daily loading dose, maximum storage capacity is reached within approximately two days. By the third day of a five-day loading period, urinary creatine excretion increases by up to 60 percent—indicating that excess creatine is not retained.[4] Thus, loading beyond three days may be unnecessary for most individuals, though interindividual variability exists.
Should You Load? A Goal-Driven Decision
The decision to implement a loading phase is highly individualized and should be guided by specific goals.
For Athletes Seeking Rapid Benefits
Loading accelerates the onset of creatine’s ergogenic benefits. For resistance-trained athletes (e.g., weightlifters), a loading phase may be advantageous to expedite gains in muscular strength, power, and hypertrophy. However, after one month, intramuscular creatine stores are identical regardless of whether a loading phase was utilized. In the absence of an imminent competition or time-sensitive goal, a gradual, low-dose approach is preferable.
For Weight-Class or GI-Sensitive Individuals
Weight-class athletes may benefit from avoiding loading phases to minimize acute, undesirable weight gain associated with water retention from high-dose creatine. (Conversely, some individuals report a psychological benefit from this initial weight increase—though it is primarily water weight—due to a perceived increase in muscular size.) Additionally, gastrointestinal discomfort is a common adverse effect of loading phases, likely due to increased water intake and retention; this can be mitigated with a low-dose regimen.
References
Chilibeck, P. D., Chrusci-Ll, M. J., Chadi, K., Davison, K. S., & Burke, D. G. (2005). Creatine monohydrate and resistance training increase bone mineral content and density in older men. The Journal, 9(5).
Tarnopolsky, M. A., & Maclennan, D. P. (2000). Creatine monohydrate supplementation enhances high-intensity exercise performance in males and females. International Journal of Sport Nutrition and Exercise Metabolism, 10(4), 452–463.
Kutz, M. R., & Gunter, M. J. (2003). Creatine monohydrate supplementation on body weight and percent body fat. The Journal of Strength & Conditioning Research, 17(4), 817–821.
Persky, A. M., Brazeau, G. A., & Hochhaus, G. (2003). Pharmacokinetics of the dietary supplement creatine. Clinical Pharmacokinetics, 42(6), 557–574.
Hultman, E., Soderlund, K., Timmons, J. A., Cederblad, G., & Greenhaff, P. L. (1996). Muscle creatine loading in men. Journal of Applied Physiology, 81(1), 232–237.
Buford, T. W., Kreider, R. B., Stout, J. R., Greenwood, M., Campbell, B., Spano, M., ... & Antonio, J. (2007). International Society of Sports Nutrition position stand: creatine supplementation and exercise. Journal of the International Society of Sports Nutrition, 4(1), 6.
