Everything the research actually shows about creatine — efficacy, dosing, timing, safety, and who it works for. No myths, no marketing.
Creatine is a naturally occurring compound synthesised from arginine, glycine, and methionine — primarily in the liver and kidneys. It is stored as phosphocreatine in skeletal muscle, where it serves as a rapid ATP buffer during high-intensity contractions.
The mechanism: During maximal effort (sprints, heavy lifts), ATP depletes faster than aerobic metabolism can replenish it. Phosphocreatine donates a phosphate group to ADP → ATP, extending the duration of maximal output before fatigue.
The result: more reps completed at a given weight, higher peak power output, and faster recovery between sets.
| Form | Efficacy vs Monohydrate | Cost | Evidence Base |
|---|---|---|---|
| Creatine Monohydrate | ✅ Reference standard | $ Low | 500+ RCTs |
| Creatine HCl | ≈ Equivalent (claimed higher absorption unproven) | $$$ High | Under 10 RCTs |
| Buffered Creatine (Kre-Alkalyn) | ≈ Equivalent | $$$ High | 3 RCTs |
| Creatine Ethyl Ester | ❌ Inferior (converts to creatinine faster) | $$ Medium | 5 RCTs |
| Micronised Monohydrate | ≈ Equivalent (better mixability only) | $$ Medium | Monohydrate data applies |
Verdict: No creatine form outperforms monohydrate in head-to-head trials. Alternative forms exist solely as marketing differentiation.
A 2013 study by Antonio & Ciccone found a statistically significant but small advantage for post-workout creatine consumption. The practical magnitude is negligible — consistency of daily intake matters far more than window timing.
| Outcome | Effect Size | Notes |
|---|---|---|
| Strength (1RM) | +5–8% | Across multiple muscle groups in RCTs |
| Power output | +10–15% | Peak Watts in sprint protocols |
| Lean mass (8 weeks) | +1–2 kg | Includes water retention in muscle |
| Cognitive performance | Small-moderate | Most pronounced in sleep-deprived subjects |
| Endurance (>90 sec) | Minimal | Minimal benefit beyond PCr-dependent efforts |
Creatine response is not universal. "Non-responders" (those who experience minimal benefit) typically already have high resting muscle phosphocreatine from dietary creatine (red meat, fish) or genetic variation.
| Population | Expected Benefit | Notes |
|---|---|---|
| Strength athletes | ✅ High | Well-documented across power sports |
| Vegetarians/vegans | ✅ Very High | Lower dietary creatine = more room for saturation |
| Older adults (50+) | ✅ High | Protects against age-related muscle loss |
| Endurance athletes | ⚠️ Low-Moderate | Some benefit in high-intensity intervals |
| Non-responders | ❌ Minimal | Estimated 20–30% of users |
These serve different mechanisms. Protein provides substrate for muscle protein synthesis; creatine improves training output. Both are additive. If choosing one, prioritise meeting protein targets (1.6–2.2g/kg bodyweight) before adding creatine.
Emerging evidence suggests modest cognitive benefits, particularly under conditions of sleep deprivation or mental fatigue. A 2022 systematic review found improvements in memory and reaction time with creatine supplementation in healthy adults, though effect sizes were smaller than in athletic populations.