Creatine and Muscle Growth

What the meta-analyses report

A 2024 systematic review and meta-analysis of 12 randomized studies in adults under 50 found that creatine combined with resistance training increased lean body mass by about 1.14 kg compared with resistance training alone, alongside small reductions in body fat percentage and body fat mass. A separate 2022 meta-analysis of 35 randomized controlled trials with 1,192 participants similarly reported that creatine paired with resistance training increased lean body mass by about 1.10 kg, regardless of age. Both analyses point in the same direction: creatine offers a measurable but modest additional gain in lean mass when added to a structured training stimulus.^{[1], [2]}

Importantly, the benefit in these analyses was linked to the combination of creatine and resistance training rather than to creatine alone. In the 2022 meta-analysis, creatine without exercise produced essentially no change in lean body mass, and the effect with mixed exercise was not statistically significant. The doses examined in this literature were in the range of roughly 7 g/day or about 0.3 g/kg of body mass per day, which is consistent with commonly studied maintenance amounts of a few grams daily, sometimes preceded by a short higher-intake loading phase.^{[1], [2]}

Who responds and by how much

The average effect should not be read as identical for everyone. The 2022 meta-analysis reported a statistically significant lean body mass gain in males of about 1.46 kg, while the corresponding estimate in females of about 0.29 kg was not statistically significant. Whether this reflects a genuinely smaller response in females or simply fewer and smaller trials in that subgroup is not resolved by the data, so the subgroup findings are best treated as preliminary signals rather than firm conclusions.^[2]

Evidence limitations

The pooled estimates carry meaningful caveats. The 2022 meta-analysis explicitly noted high heterogeneity across individual studies, meaning the trials differed substantially in design, population, dose, and duration. The absolute gains are also small, on the order of about 1 kg of lean mass, and were observed specifically when creatine accompanied resistance training; creatine without training did not significantly increase lean body mass. These findings describe group averages from research settings and are not a substitute for individualized guidance.^{[1], [2]}

Subgroup results, such as the larger response reported in males than females, come from a single meta-analysis and should be interpreted cautiously given the between-study variability and the differing number of trials available per subgroup.^[2]