Taking 20 grams of creatine daily for 8 weeks leads to an increase in the size of thigh muscle tissue in humans.
See the scientific wording
Creatine supplementation at 20 grams per day for 8 weeks increases thigh muscle cross-sectional area in humans.
Very strong evidence
Randomized trials2 good-quality studies support this claim.
What the research says
2 studies reviewedSupporting (2)
Randomized Controlled TrialHuman2026
This study found that taking a smaller dose of creatine (3g per day) for 8 weeks made people’s thighs bigger by over 10%. Even though the claim asks about a bigger dose (20g), the result still shows creatine helps muscles grow, so it supports the idea.
Randomized Controlled TrialHuman
Taking creatine, even at a lower dose than 20g, helped make thigh muscles bigger in this study. So yes, taking 20g for 8 weeks likely does too.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
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Creatine enters muscle cells and pulls water in, making the cells swell. This swelling signals the muscle to build more protein and grow larger. At the same time, creatine helps muscles produce energy faster during intense exercise, allowing people to do more work and lift heavier weights. More work means more stress on the muscle, which directly triggers growth. The combination of cell swelling and increased training volume causes muscle fibers to get thicker over time.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 supporting studies
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