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Should Injured Athletes Supplement with Creatine?

Updated: Feb 11, 2020

Creatine monohydrate (CM) is one of the most-researched ergogenic (performance-enhancing) supplements, typically used for short, high-intensity sports and sport positions. Oral supplementation increases creatine levels within muscle cells, thereby increasing:


But with the well-documented swift loss of muscle mass, strength, and endurance occurring with limb immobilization due to injury (think arm slings and casts, leg braces), is there a role for CM supplementation in minimizing these losses and speeding up recovery?

Image: Chemical structure and biochemical pathway for creatine synthesis

What Happens When a Limb is Immobilized Post-injury?


Wall & van Loon (2013) reported that, in the presence of injury and immobilization, “skeletal muscle loss occurs at a rate of approximately 0.5% of total muscle mass per day [which] translates into approximately 150 g of muscle tissue lost per day in a healthy adult [and] more than 1 kg of muscle mass lost after a single week.”


The loss of muscle mass is accompanied with a reduction in the muscle’s strength, the latter of which takes longer to return during the rehabilitation phase compared to mass.


Additionally, immobilization results in reductions in insulin sensitivity, metabolic rate, and skeletal calcium (i.e., bone mineral content and density both decrease) along with an increase in body fat, length of rehabilitation, and injury reoccurrence.


The lower back and limbs (more so the soleus and gastrocnemius of the calves) are more susceptible to these changes compared to the upper limbs. Being bedridden worsens these outcomes.



What is Creatine and Where Does it Exist in the Food System?

Creatine is a non-protein amino acid that can be made within the body and gained from the diet. Ninety-five percent of the body’s creatine is stored in the muscles, with the remaining 5% in the liver, kidneys, brain, and testes.


Creatine within the muscle is broken down to creatinine, which is removed from the body via urine—meaning humans need to replace ~1-3 grams of creatine daily, a value that will depend on the person’s muscle mass (i.e., more muscle produces more creatinine waste).


With half of the body’s creatine requirement derived from diet, sources include herring (3-4.5 grams creatine per pound), pork (2.3 g), salmon, beef (both 2 g), tuna (1.8 g), and cod (1.4 g), with trace amounts coming from plant sources.


In the absence of supplements, and in the presence of a diet providing ~1-2 grams creatine daily, muscle stores are 60-80% saturated—meaning that, in those who respond to CM supplementation (not everyone does), further saturation of these levels will result in improved performance and quantity of lean mass.



Studies Evaluating CM Supplementation


The below studies walk through different phases of an injury.


A few things to keep in mind:

  • No studies exist that evaluate athletes in the injured, immobilized, and/or rehabilitation state with a CM intervention: Participants were in their early twenties to thirties, a mix of men and women, with no recent history of resistance training (or no changes in their physical activity levels throughout the study, which wasn’t defined).

  • Besides Backx et al. (2017) and Tyler et al. (2004), none of the studies controlled for diet: Researchers asked participants not to change their diets throughout the course of the study, yet total daily protein (plus its type and timing throughout the day) will influence muscle retention or loss, as will adequacy of caloric intake.

  • The treatment group receives the intervention (the CM).

  • The control group receives no CM supplementation.



Phase I: Pre-injury CM Supplementation


If we knew an athlete were about to be injured, could supplementing them with CM prior to injury help prevent or minimize these muscle losses?


Study #1: Backx et al. (2017) did just that, and it’s the only study evaluating CM loading prior to a 7-day period of immobilization.


The treatment group consumed 20 grams CM (split into four 5-gram doses) for each of the five days leading up to the “injury”. During the seven days of immobilization, followed by seven days of recovery (no immobilization), participants decreased their CM consumption to 5 grams daily. The control group received no supplemental CM.


Although creatine levels were increased in the treatment group before injury, supplementation did “not prevent or attenuate the loss of muscle mass or strength during short-term muscle disuse” when compared to the control group. Both groups lost to a similar degree.




Phase II: Immobilization and CM Supplementation


Study #2: Johnston et al. (2009) evaluated upper-limb immobilization over two seven-day periods. During one of those periods, the treatment group received 20 grams of CM (split into four 5-gram doses). Despite both the CM and control groups losing muscle mass, strength, and endurance over the course of the study, the CM group had significantly smaller losses.




Study #3: Hespel et al. (2001) evaluated lower-leg immobilization over a two-week course plus ten weeks of rehabilitation. During immobilization, the treatment group received 20 grams of CM (split into four 5-gram doses) that was reduced down to 15 grams CM for the first three weeks of rehabilitation (split into three 5-gram doses) with another reduction to 5 grams CM for the remaining seven weeks of rehabilitation. The control group received no supplemental CM.


Overall, during the immobilization period both groups saw reductions in quadricep muscle cross-sectional area (CSA), maximal dynamic knee-extension power, and isometric force (no significant differences between the two groups). “Creatine supplementation did not prevent the structural and functional changes induced by 2 weeks of immobilization.”




Phase III: Rehabilitation and CM Supplementation


Study #3: Continued here, Hespel et al. (2001) found that, over the course of the rehabilitation program, the CM group experienced larger gains in quadricep muscle CSA and peak strength (the control group did, too, but not as much). Only the CM group experienced improvements with maximal dynamic knee-extension power. The researchers concluded that “creatine supplementation is capable of shortening the duration of rehabilitation needed to restore muscle mass following an episode of disuse atrophy.”



Study #4: Tyler et al. (2004) studied 60 men and women in their early thirties following anterior cruciate ligament (ACL) reconstruction. During the first week after surgery, half of the participants consumed 20 grams of CM daily, which decreased to 5 grams daily for the remaining eleven weeks. The control group received no supplemental CM, but were given calcium tablets (dose was not specified).


The were no significant differences between the CM and control groups at multiple time points post-surgery regarding hip strength, knee strength, single-leg hop test for distance, and a subjective knee outcome score.




Take-home Message:


In regards to CM supplementation and injury in the non-athletic population (i.e., not what you’re here for, but it's what we have to work with), it may be appropriate when an upper-limb is immobilized. The research currently shows that for lower limbs, two weeks of immobilization is too short of a time to reap the benefits of supplementation.


However, once the limb is no longer immobilized and the rehabilitation phase begins, long-term CM supplementation seems to be effective.


Regarding dosing, the above studies used 5-20 grams CM split into 5-gram doses throughout the day (consumed at all meals and a bedtime snack). Of note, the power and lean muscle mass reasoning for using CM is 3-5 grams daily.


Granted, one supplement won’t make a difference if the athlete isn’t consuming adequate calories and protein throughout the day. Hit the low-hanging fruit first by helping your athlete plan timely high-protein meals and snacks that provide enough energy and micronutrients to promote healing.



Further Reading


Krieder, R.B., Kalman, D.S., Antonio, J., Ziegenfuss, T.N., Wildman, R., ... & Lopez, H.L. (2017). J Int Soc Sports Nutr,13(14):18.


Wall, B.T., & van Loon, L.J. (2013). Nutr Rev,71(4):195-208.


Backx, E.M.P., Hangelbroek, R., Snijders, T., Verscheijden, M.L., Verdijk, L.B., ... & van Loon, L.J.C. (2017). Sports Med,47(8):1661-1671.


Johnston, A.P., Burke, D.G., MacNeil, L.G., & Candow, D.G. (2009). J Strength Cond Res,23(1):116-120.


Hespel, P., Op't Eijnde, B., Van Leemputte, M., Urso, B., Greenhaff, P.L., ... Richter, E.A. J Physiol,536(Pt 2):625-633.


Tyler, T.F., Nicholas, S.J., Hershman, E.B., Glace, B.W., Mullaney, M.J., & McHugh, M.P. (2004). Am J Sports Med,32(2):383-388.


Balsom, P., & Soderlund, K. (1994). Sports Med,18(4):268-280.

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