Does Creatine Affect Aerobic Capacity? The Impact on Endurance

October 18, 2025 •

3 min read

Creatine is one of the most widely researched and effective supplements for improving performance in high-intensity, short-duration exercises. However, its relationship with endurance performance and the central question of whether creatine affects aerobic capacity is far more complex and nuanced.

Quick Summary

The impact of creatine on aerobic capacity is indirect, primarily benefiting high-intensity efforts within endurance events rather than steady-state cardio. Benefits include improved glycogen storage and recovery, but athletes should consider potential weight gain from water retention, especially in weight-bearing sports.

Key Points

Anaerobic vs. Aerobic: Creatine primarily benefits the anaerobic system for short, high-intensity efforts, not the steady-state aerobic system.
Mixed Endurance Results: Research shows mixed to minimal direct effects on pure aerobic capacity metrics like VO2 max, especially for steady-state endurance activities.
Weight Gain: Creatine causes temporary water retention and weight gain, which can negatively impact performance in weight-bearing endurance sports like running.
Targeted Benefits: Endurance athletes benefit most from creatine during high-intensity surges, intervals, and end-of-race sprints.
Indirect Support: It supports endurance by increasing muscle glycogen storage and accelerating recovery from intense training.
Individualized Approach: Dosage and strategy should be tailored to the athlete's sport and goals, with non-loading options available to minimize weight gain.

The Core Function of Creatine: A Focus on Anaerobic Power

Creatine is a naturally occurring compound crucial for energy production, particularly during rapid, high-intensity movements. Stored mostly in skeletal muscle as phosphocreatine (PCr), it helps regenerate adenosine triphosphate (ATP) during intense efforts like sprinting or weightlifting. This phosphocreatine system is the quickest way for muscles to get energy for up to 15 seconds of intense work. Supplementing with creatine increases PCr stores, allowing for longer and more intense anaerobic activity, which is why it's highly effective for sports needing short, powerful bursts.

Creatine's Influence on Aerobic Capacity: A Complex Relationship

Unlike its clear impact on anaerobic performance, creatine's effect on pure aerobic capacity is less straightforward. Aerobic activities, like long-distance running, rely on oxidative phosphorylation for sustained energy. The PCr system's direct contribution decreases in longer, lower-intensity exercise. Studies on creatine and aerobic markers like VO2 max show mixed results, with some finding no significant direct improvement. Some reviews even suggest a slightly negative effect on relative VO2 max (mL/kg/min). This is thought to be due to temporary water retention and weight gain from creatine, which can affect performance in weight-bearing activities.

Indirect Benefits for the Endurance Athlete

Though not a direct aerobic booster, creatine offers indirect benefits for endurance athletes:

Enhanced Glycogen Storage: Creatine can increase muscle glycogen, a key fuel for sustained, moderate-to-high-intensity aerobic exercise, potentially delaying fatigue.
Improved Recovery: With antioxidant and anti-inflammatory properties, creatine can help reduce muscle damage and inflammation after intense exercise, aiding faster recovery between training sessions.
Improved Buffering Capacity: PCr breakdown helps buffer hydrogen ions in muscles, delaying fatigue during high-intensity efforts or sprints within longer events.
Support for High-Intensity Intervals: Creatine can significantly improve performance in repeated high-intensity intervals, leading to better adaptations for aerobic fitness.

The Creatine Trade-Off: Weighing the Pros and Cons

For endurance sports, the decision to use creatine involves balancing benefits and drawbacks, which vary by sport and individual.


Feature	Potential Pros for Endurance Athletes	Potential Cons for Endurance Athletes
Performance	Enhances performance during high-intensity intervals, surges, and final sprints.	May have minimal direct effect on steady-state aerobic performance.
Recovery	Reduces muscle damage and inflammation, leading to faster recovery.	Individual responses can vary significantly, with some athletes seeing minimal benefits.
Fueling	Increases muscle glycogen storage, providing more fuel for longer efforts.	Potential for gastrointestinal discomfort, especially during the loading phase.
Body Weight	None (creatine does not cause fat gain).	Can cause temporary weight gain from water retention, which may hinder performance in weight-bearing sports like running.
Thermoregulation	Enhances hydration status, which can aid in thermoregulation during exercise in the heat.	The weight gain might be a psychological or practical drawback for some athletes.

Practical Considerations for Endurance Athletes

To minimize water retention and weight gain, endurance athletes might use a low-dose approach (3-5g daily) without a loading phase. Consistency is key for maintaining elevated creatine levels, and taking it with carbohydrates post-workout can aid absorption and glycogen replenishment. Testing during the off-season is recommended to assess individual response before competitions.

Conclusion: A Nuanced Perspective

In conclusion, while creatine affects aerobic capacity indirectly, it primarily benefits the anaerobic system. Direct performance gains in purely steady-state aerobic activities are likely minimal. Its main value for endurance athletes comes from improving high-intensity aspects like intervals and sprints. Enhanced recovery and glycogen storage also provide indirect support. However, temporary weight gain from water retention is a factor, especially in weight-bearing sports. Creatine is best seen as a strategic tool for marginal gains, usable during specific training phases. For further details, the International Society of Sports Nutrition Position Stand is a reliable source.

Potential Mechanisms That Influence Aerobic Performance

Creatine's impact extends to physiological factors relevant to endurance. By increasing phosphocreatine stores, it boosts ATP regeneration during recovery and, through hydration, supports protein and glycogen synthesis. As an antioxidant and anti-inflammatory, it aids recovery from prolonged aerobic activity. Its buffering capacity helps manage acidity during intense bursts, allowing for sustained power. These effects show creatine's role in supporting training and recovery, which can lead to long-term aerobic improvements.

Weighing the Individual Response

Responses to creatine vary based on genetics, baseline creatine levels, and muscle fiber type. Individuals with lower baseline stores, like vegetarians, may see greater benefits. A personalized approach is important; testing creatine during the off-season helps athletes gauge their response and determine if the benefits align with their goals and sport.

Frequently Asked Questions

While creatine may provide a small benefit for your final sprint in a marathon, it is unlikely to significantly improve your overall marathon time. The temporary weight gain from water retention could even be a disadvantage for some long-distance runners.

Yes, creatine can be particularly effective for HIIT. It enhances performance during repeated bursts of high-intensity effort, allowing you to sustain a higher power output during interval training sessions.

Yes, creatine monohydrate is generally considered safe for long-term use in healthy individuals when taken at recommended dosages. It is important to consult a healthcare provider, especially if you have pre-existing kidney conditions.

No, research indicates that creatine does not cause dehydration or cramping. In fact, by pulling water into muscle cells, it can improve overall hydration status and support better thermoregulation.

Endurance athletes can use a low-dose, non-loading protocol, such as 3–5 grams per day. This approach saturates muscle stores over several weeks without the rapid fluid retention associated with a loading phase.

Creatine aids recovery by reducing exercise-induced muscle damage and inflammation through its antioxidant and anti-inflammatory effects. This helps repair muscle fibers more quickly between training sessions.

Directly, no. Creatine does not appear to increase VO2 max. Some studies even show a slight decrease in relative VO2 max (mL/kg/min) due to the associated water weight gain. However, improvements in ventilatory threshold have been noted, which indicates better exercise efficiency.