Is Creatine Beneficial for Athletic Performance?
Yes, creatine supplementation is beneficial for athletic performance—it improves high-intensity repeated sprint performance, enhances training capacity, and increases muscle strength, power, and lean body mass, with no significant negative health effects when following appropriate protocols. 1
Performance Benefits
Creatine works by increasing muscle creatine stores by approximately 20%, which enhances the resynthesis of phosphocreatine and provides rapid ATP regeneration during intense exercise. 2, 3 This mechanism translates into measurable performance improvements:
- Improves high-intensity repeated sprint performance by increasing available energy for short-duration, powerful movements 1, 3
- Enhances training capacity and chronic training adaptations, including increased muscle strength, power, and lean body mass 1, 3
- May support brain function by increasing phosphocreatine stores in brain tissue, potentially improving cognitive processing 1, 2
The evidence is strongest for short-duration, high-intensity activities dependent on the ATP-CP energy system, particularly exercises involving repeated bouts with limited recovery time. 4, 5
Recommended Supplementation Protocol
The UEFA Expert Group Statement provides clear dosing guidelines that balance efficacy with minimizing body mass increases:
Loading Phase
Maintenance Phase
Alternative Low-Dose Approach
Optimization Strategy
- Concurrent consumption with ~50g of protein and carbohydrates may enhance muscle creatine uptake via insulin stimulation 1, 3
- After cessation, approximately 4-6 weeks are required for creatine levels to return to baseline 1, 3
Safety Profile
Creatine monohydrate supplementation is safe with no significant adverse effects on organ function when following appropriate dosing protocols. 2 The evidence base is robust:
- No significant negative health effects have been reported when following appropriate protocols in healthy individuals across short-term (5 days), medium-term (9 weeks), and long-term (up to 5 years) studies 2, 6, 5
- Studies show both short- and long-term supplementation is safe and well tolerated in healthy individuals 5
Expected Side Effect
- The primary side effect is a predictable 1-2 kg increase in body mass, typically attributable to water retention or increased protein synthesis rather than pathological changes 1, 2, 3
Critical Safety Considerations
While creatine is safe for healthy individuals, specific monitoring is warranted in certain contexts:
Renal Function Monitoring
- If a patient has evidence of renal dysfunction, discontinue creatine supplementation 2
- Creatine may affect the evaluation of glomerular filtration rate (GFR) by altering exogenous creatinine generation, but does not affect actual kidney function 2, 7
- In kidney donor populations specifically, dietary supplement use including creatine should be discouraged due to unknown effects and potential interference with GFR estimation 1
Enzyme Level Interpretation
- When interpreting creatine phosphokinase (CPK) levels in athletes taking creatine, levels above 3000 U·L⁻¹ have been detected after maximal resistance exercise without pathological significance 2, 3
- Elevated enzyme levels should be interpreted in context of training history, muscle mass, ethnicity, and timing of blood collection 3
Common Pitfalls to Avoid
- Do not use creatine for endurance sports—the effects diminish as exercise duration increases, and it is not useful for endurance activities 8, 4
- Ensure third-party testing certification of supplements (e.g., Informed Sport, Kölner Liste) to reduce risk of contamination with banned substances 1
- Monitor WADA status—while creatine is currently permitted, regulations should be checked prior to use in competitive athletes 1
- Avoid in patients with pre-existing renal dysfunction—though monitoring is prudent even in healthy individuals 2