Is Creatine Good for Endurance Athletes, Not Just Bodybuilders?

If you spend any time on fitness Instagram, you have probably absorbed two “facts” about creatine: it is for people who lift heavy things in tank tops, and if you are a runner or cyclist it will just make you heavier and slower. We hear a version of this from the endurance athletes we coach all the time, usually phrased as “should I even bother with creatine, or is that a gym bro thing?”

Here is the fun part. The actual endurance literature says something much more interesting than the influencers do, and some of the best studies on this were run by the exact researchers we trust most in sports nutrition, including Louise Burke’s group. So let’s dig into what the research really shows, where creatine genuinely helps endurance athletes, and where the skeptics have a point.

First, what creatine actually does

Creatine helps your muscles rapidly regenerate ATP through the phosphocreatine system, which is the energy system you lean on during short, hard efforts: a surge to close a gap, a punchy climb, the final sprint to the line. Supplementing raises your muscle creatine stores, which improves your capacity to repeat those high intensity efforts. That is why it became a strength sport staple, and it is also exactly why it was dismissed for endurance for so long. A steady state marathon does not look like a set of squats.

But racing is not steady state. Races are decided in surges, attacks, and finishing kicks. A 2023 review by Forbes and colleagues in the Journal of the International Society of Sports Nutrition makes exactly this argument: creatine is unlikely to make your cruising pace faster, but it can matter in the moments that actually decide races (Forbes et al., 2023).

What the research shows in actual endurance athletes

The study we point athletes to most is Tomcik et al. (2018), published in Medicine and Science in Sports and Exercise with Louise Burke as senior author. Eighteen well trained male cyclists (VO2peak around 65 ml/kg/min) did a 120 km time trial that included repeated 1 km and 4 km sprints, after either creatine loading (20 g per day for 5 days, then 3 g per day) or placebo, combined with moderate or high carbohydrate intakes. Creatine did not make the overall time trial faster. But the creatine group produced more power in the final 4 km sprint, exactly when everyone was cooked, and creatine plus carb loading elevated muscle glycogen above carb loading alone (Tomcik et al., 2018). Worth repeating: this was well trained male cyclists, so if you are a female athlete, a runner, or newer to training, the exact numbers may not transfer to you, though the mechanism should.

That glycogen finding deserves its own sentence. Creatine taken with carbohydrate appears to help you store more glycogen, which is the whole point of a carb load before a long race (Tomcik et al., 2018; Forbes et al., 2023). So the supplement everyone says is irrelevant for endurance may actually make your pre race carb load work better.

It gets better with the sprint data. Engelhardt et al. (1998) had competitive triathletes ride at an endurance pace with 15 second sprint intervals mixed in, and creatine supplementation improved sprint power by around 18 percent without hurting the aerobic work in between (Engelhardt et al., 1998). Again, note the population: trained triathletes, short study, small sample, and mostly male. This is a consistent theme in creatine research, which we will come back to.

And for recovery: Santos et al. (2004) gave experienced marathon runners 20 g of creatine per day for 5 days before a 30 km race and measured markers of muscle damage and inflammation afterward. The creatine group showed substantially lower creatine kinase, LDH, and inflammatory markers than the control group (Santos et al., 2004). One race, small group of seasoned runners, so treat it as promising rather than proven, but it fits with the broader recovery literature (Forbes et al., 2023).

Okay, but the weight gain thing is real

This is where we will defend a piece of the skepticism. Creatine pulls water into the muscle, and in the Tomcik study the creatine group gained about 1.5 percent body mass versus about 1 percent with placebo (Tomcik et al., 2018). On a bike, where your weight is supported, that extra kilo did not hurt performance, including on an inclined ride to fatigue. Running is weight bearing, so a kilo of water is not free there, especially if your goal race is hilly.

Our take as coaches: this is a reason to be thoughtful, not a reason to skip creatine. Trial it in a training block, never race week. Skip the aggressive 20 g loading phase and just take 3 to 5 g per day, which gets your stores to the same place in about 3 to 4 weeks with less water weight all at once (Antonio et al., 2021). If you are a runner chasing a goal time on a hilly course, weigh the tradeoff. If you are a cyclist, triathlete, or swimmer, the weight argument mostly falls apart.

What about women?

Most creatine research was done on men. Smith-Ryan and colleagues point out that around 70 to 80 percent of creatine studies are in male participants, while women have lower endogenous creatine stores and may plausibly benefit just as much or more, with emerging evidence across the lifespan for muscle, recovery, and even brain outcomes (Smith-Ryan et al., 2021). So when someone tells you creatine is not for women, the honest answer is that the research gap is the problem, not the supplement. The dosing that works in the studies we do have is the same 3 to 5 g of creatine monohydrate per day.

The myths, quickly

The claims that creatine wrecks your kidneys, causes hair loss, or is basically a steroid have been directly addressed in the literature. Antonio et al. (2021) walked through the evidence on all of these: no kidney harm in healthy people at recommended doses, no good evidence for hair loss (the worry traces back to a single study on DHT levels, not actual hair), and creatine is not remotely a steroid. The International Society of Sports Nutrition position stand reaches the same conclusion on safety, calling creatine monohydrate one of the most studied and safest supplements available (Kreider et al., 2017). Caveat where it belongs: if you have kidney disease or any medical condition, talk to your doctor first, because “safe in healthy adults” is exactly that.

How we would actually use it

Creatine monohydrate, 3 to 5 g per day, every day, timing does not matter. That is it. You do not need fancy forms, and you definitely do not need the pre workout blend with 14 other ingredients. Look for creatine monohydrate on its own, ideally third party tested (NSF Certified for Sport or Informed Sport) since supplement quality control is a genuine problem in this industry.

Two brands we consistently recommend to our athletes are Thorne and Momentous, and you can get both through our Fullscript dispensary: get 20% off creatine and anything else in the Fullscript database here. Fullscript carries practitioner grade brands like Thorne, Momentous, Pure Encapsulations, Metagenics, and others, and the 20 percent discount applies across their whole catalog, which is usually a better deal than retail for these brands.

The bottom line

The influencer version of creatine (“bulking supplement, skip it if you run”) does not survive contact with the endurance literature. Creatine will not raise your FTP or your easy pace. It can improve the surges and finishing sprints that decide races, boost the glycogen you store during a carb load, and possibly speed recovery from long hard efforts. The costs are about a kilo of water weight and the minor hassle of a daily habit. For most cyclists and triathletes we work with, that trade is clearly worth it. For runners, it depends on your course, your goals, and how your body responds, which is exactly the kind of thing we sort out in 1:1 coaching.

Want help with the bigger picture of fueling and supplements? Our free nutrition guides, cheat sheets, and resources are a good place to start, and they cost exactly nothing.

References

Antonio, J., Candow, D. G., Forbes, S. C., et al. (2021). Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Journal of the International Society of Sports Nutrition, 18(1), 13.

Engelhardt, M., Neumann, G., Berbalk, A., & Reuter, I. (1998). Creatine supplementation in endurance sports. Medicine and Science in Sports and Exercise, 30(7), 1123-1129.

Forbes, S. C., Candow, D. G., et al. (2023). Creatine supplementation and endurance performance: surges and sprints to win the race. Journal of the International Society of Sports Nutrition, 20(1), 2204071.

Kreider, R. B., Kalman, D. S., Antonio, J., et al. (2017). 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, 14, 18.

Santos, R. V. T., Bassit, R. A., Caperuto, E. C., & Costa Rosa, L. F. B. P. (2004). The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race. Life Sciences, 75(16), 1917-1924.

Smith-Ryan, A. E., Cabre, H. E., Eckerson, J. M., & Candow, D. G. (2021). Creatine supplementation in women’s health: a lifespan perspective. Nutrients, 13(3), 877.

Tomcik, K. A., Camera, D. M., Bone, J. L., Ross, M. L., Jeacocke, N. A., Tachtsis, B., Senden, J., van Loon, L. J. C., Hawley, J. A., & Burke, L. M. (2018). Effects of creatine and carbohydrate loading on cycling time trial performance. Medicine and Science in Sports and Exercise, 50(1), 141-150.