Does creatine increase muscle strength?
Further research is very unlikely to change the conclusion.
How we rated this ▾Hide rating detail ▴
| Domain | Rating | Why |
|---|---|---|
| Risk of bias | Not serious | Most pooled trials were randomized and placebo-controlled, and the outcome is objectively measured rather than self-reported. |
| Inconsistency | Not serious | Effect direction is consistent across four independent meta-analyses covering different populations and muscle groups. |
| Indirectness | Not serious | Trials measured strength directly — one-repetition maximum and comparable performance tests — not a biomarker standing in for it. |
| Imprecision | Not serious | Pooled samples run to hundreds of participants and confidence intervals exclude no effect. |
| Publication bias | Serious | Sports-nutrition literature carries known small-study and industry-funding pressures, and some pooled trials are small. |
Creatine monohydrate reliably increases muscle strength when combined with resistance training. Multiple meta-analyses of randomized trials find gains of roughly 5-10% over training alone, across upper and lower body, in both younger and older adults. It is among the most consistently replicated findings in sports nutrition.
5 studies analysed4 systematic reviewsLast reviewed
What the evidence shows
- The effect is real, replicated, and modest in absolute terms — it adds to training, it does not replace it.
- It holds for both upper and lower body, and for older adults as well as young trained men.
- Monohydrate is the form the evidence actually covers.
Why scientists think this
Creatine increases intramuscular phosphocreatine stores, which regenerate ATP during short, high-intensity efforts and allow slightly greater training volume.
The strength gain is therefore partly indirect: better work capacity per session accumulates into larger training adaptations over weeks.
Where studies disagree
Good-quality studies do not always agree. Where they conflict, we show the conflict rather than picking the tidier answer.
How large the effect actually is
One reading
Dedicated strength meta-analyses report a clear and consistent benefit on directly measured strength outcomes.
The other
Broader syntheses covering many performance outcomes report smaller average effects, because the benefit is concentrated in short high-intensity tasks rather than spread evenly across all performance measures.
The analyses pool different outcome sets. The disagreement is about scope, not about direction.
What we still don’t know
- Pooled trials are mostly short, typically weeks to a few months, so very long-term strength trajectories are less well characterized.
- Responders and non-responders exist: baseline muscle creatine content varies, and people who already have high stores gain less.
- Much of the literature studies young men, though the older-adult meta-analysis narrows this gap.
- Industry involvement is common in this field, which is why publication bias is rated serious despite the consistency of results.
What would change our mind
- A large, pre-registered, independently funded trial finding no strength advantage over placebo in resistance-trained adults.
- A meta-analysis restricted to low-risk-of-bias trials that reports a null pooled effect on directly measured strength.
- Evidence that the pooled effect is driven mainly by industry-funded trials and disappears among independently funded ones.
The evidence
Every study that informed this assessment, strongest evidence first — including the ones that disagree with our conclusion.
| Study | Design | What it measured | Finding | Quality |
|---|---|---|---|---|
Lanhers et al. 2017Creatine Supplementation and Upper Limb Strength Performance: A Systematic Review and Meta-Analysis Sports Medicine
Companion analysis to the lower-limb review by the same group, using the same methodology. | Meta-analysis | Upper-limb strength performance | Supports | |
Lanhers et al. 2015Creatine Supplementation and Lower Limb Strength Performance: A Systematic Review and Meta-Analyses Sports Medicine
Pre-specified systematic search with pooled randomized evidence; the strongest single source on this question. | Meta-analysis | Lower-limb strength performance (1RM and comparable tests) | Supports | |
Chilibeck et al. 2017Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a meta-analysis Open Access Journal of Sports Medicine
Extends the finding to an older population, which is where generalizability was weakest. | Meta-analysis | Muscular strength and lean tissue mass | Supports | |
Branch 2003Effect of creatine supplementation on body composition and performance: a meta-analysis International Journal of Sport Nutrition and Exercise Metabolism
Older synthesis and broader in scope than the outcome asked about here; downgraded one tier for age and heterogeneity. | Meta-analysis | Performance and body composition outcomes, including strength | Supports | |
Kreider et al. 2017International 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
Position stand from a sports-nutrition body. Used for context and for the monohydrate-form question, never as the basis for the verdict. | Guideline | Exercise performance and safety outcomes across the literature | Supports | Industry ties |
How we researched this284 screened → 5 included
Databases searched
PubMed, Europe PMC, OpenAlex — searched · 1990-2026
Search strings
- creatine[MeSH] AND (muscle strength[MeSH] OR resistance training[MeSH])
- creatine monohydrate AND (1RM OR "one repetition maximum") AND randomized
- creatine supplementation strength meta-analysis
Included if
- Human participants
- Strength measured directly (1RM or comparable objective test)
- Randomized design, or systematic review/meta-analysis of randomized designs
Excluded if
- Animal and in-vitro work
- Studies measuring only body composition or biomarkers without a strength outcome
- Non-monohydrate forms without a monohydrate comparator
Screening
284 records screened → 37 full texts reviewed → 5 included
Notable exclusions
Single-arm and non-randomized creatine loading studies reporting strength change
No placebo comparator, so training effect cannot be separated from supplementation effect.
No external expert reviewer on this page yet. How we assign review.
How AI was used
AI planned the literature search, screened abstracts against our inclusion criteria, extracted study details into the evidence table, drafted this synthesis from that table, and audited every claim against its cited sources. It did not answer from its own knowledge and did not decide what gets published. A human selected the question, checked the evidence table against the sources, and signed off on the verdict. Full disclosure.
Change history
No changes since first publication.