Creatine and Endurance Performance: Can It Help Without Adding Unwanted Weight?

For years, creatine has been associated mainly with strength athletes, bodybuilders and explosive sports. But endurance athletes are increasingly asking whether it can offer an advantage in cycling, running, rowing and triathlon, particularly when races involve repeated surges or a powerful finishing sprint.

The bigger question is whether those potential benefits are worth the possibility of gaining extra body weight. For an athlete carrying every gram over a marathon or mountain climb, that trade-off matters.

Why Would an Endurance Athlete Use Creatine?

Creatine helps replenish phosphocreatine, an energy system that supports rapid ATP production during short, intense efforts. While traditional endurance exercise relies heavily on aerobic metabolism, races rarely remain completely steady from start to finish.

Breakaways, hill attacks, sprint finishes and repeated accelerations can all place substantial demands on the phosphocreatine system. This is where creatine may have more relevance than its traditional reputation suggests.

A scoping review of 38 randomized controlled trials found that creatine was most promising in endurance and mixed-sport situations involving repeated high-intensity efforts, sprint finishes and power-endurance demands. However, the researchers also noted that evidence for aerobic performance remained limited and inconsistent.

What Does the Recent Research Say?

The evidence is far from a simple “creatine improves endurance” message.

In a study of endurance-trained men and women, participants completed five days of creatine loading before undertaking sprint and short time-trial tests. Creatine improved 15-second sprint power, but it did not improve the six-minute time trial. The researchers concluded that creatine and caffeine appeared to have different performance applications rather than producing an additive effect.

Research involving professional cyclists has been less encouraging. Barranco-Gil and colleagues gave professional U23 cyclists 20 grams of creatine daily during a demanding training camp. The supplementation did not significantly improve performance, recovery or body-composition outcomes, suggesting that a short, high-dose protocol may not provide a meaningful advantage during intense endurance training.

Another trial found that five days of creatine loading improved strength-endurance performance in strength-trained men, increasing repetitions and total work without changing maximal strength. While this wasn't an endurance-sport study, it provides useful evidence that creatine can influence the ability to sustain repeated efforts.

A network meta-analysis provides another important piece of the puzzle. Across 30 randomized controlled trials, creatine tended to improve mean power and peak power, but it did not improve VO₂max. Interestingly, protein showed the strongest evidence for improving endurance performance in that analysis.

The Weight-Gain Question

The main concern for many endurance athletes isn't whether creatine works. It is whether the potential benefit comes with additional weight.

Creatine can increase total body mass, particularly during loading. This is primarily associated with increased water stored within muscle rather than an immediate increase in body fat. The scoping review found that small increases in total body mass were common, while evidence regarding fat-free mass and aerobic outcomes was inconsistent.

That distinction matters. An extra kilogram may be relatively unimportant for a flat cyclist but potentially more consequential for a hill runner or mountain athlete.

Professor Graeme Close, a sports nutrition and human physiology researcher at Liverpool John Moores University who has worked extensively with elite athletes, has highlighted the issue from a weight-sensitive perspective: “One to two pounds for these guys is huge.”

Can You Minimize the Extra Weight?

There is no guaranteed way to eliminate creatine-related water retention. However, athletes don't necessarily need to use an aggressive loading phase.

A conventional approach often involves several days of high-dose supplementation followed by a lower maintenance intake. A smaller daily intake can gradually increase muscle creatine stores without the same rapid loading strategy, although individual responses vary.

For athletes searching for the right creatine dosage, the decision should therefore depend on the sport, body-mass sensitivity, competition calendar and individual response rather than assuming that more is better.

Dr. Louise Burke, a leading sports dietitian and researcher who has worked extensively with Olympic and elite endurance athletes, has emphasized that creatine should be used selectively rather than automatically. She describes creatine as something that should be considered when there is a specific evidence-based reason for an athlete to use it.

Who Might Benefit Most?

The strongest case may be for endurance athletes whose events contain substantial high-intensity components.

For a cyclist who regularly attacks on climbs, a runner who relies on a finishing kick, or a triathlete facing repeated changes of pace, the potential improvement in short-duration power could be more relevant than an effect on steady-state aerobic capacity.

This helps explain why interest in creatine for runners is growing despite the lack of evidence that it directly increases VO₂max.

Likewise, creatine for endurance athletes should not be viewed as a replacement for carbohydrate, hydration, adequate energy intake or a well-designed training program. It is better understood as a potentially useful tool for specific performance demands.

So, Is Creatine Worth It?

The answer depends heavily on the athlete and event.

If your sport rewards repeated sprints, attacks or a strong finishing effort, creatine may offer a worthwhile performance advantage. If your event is almost entirely steady-state and every additional gram of body mass matters, the calculation becomes less favorable.

The current evidence does not support creatine as a universal endurance-performance supplement. Instead, it suggests a more targeted approach, where the potential power and repeated-effort benefits are weighed against individual tolerance for increased body mass.

A More Targeted Role for Creatine

Creatine isn't necessarily an endurance athlete's enemy, nor is it a guaranteed performance booster. The latest evidence points toward a narrower but potentially valuable role, particularly for endurance events that demand repeated high-intensity efforts.

For some athletes, a small increase in body mass may be a reasonable price for greater sprint or power capacity. For others, particularly weight-sensitive competitors, the trade-off may not make sense.

The smartest approach is therefore not to ask whether creatine is “good” or “bad” for endurance athletes. The better question is whether its specific benefits match the demands of your event.