Research Review: Creatine Supplementation Increases Lean Mass and Reduces Fat When Combined With Resistance Training

By Rob Shaul, Founder

BLUF

A 2024 meta-analysis in the Journal of Strength and Conditioning Research reviewed 12 randomized controlled trials examining creatine supplementation combined with resistance training (RT) in healthy adults under 50. Across studies, creatine users gained an average of 1.14 kg more lean body mass (LBM) and reduced body fat mass by 0.7 kg and body fat percentage by 0.9% compared to those doing RT alone. These changes occurred regardless of training experience or total training volume. Adding carbohydrate to creatine did not improve results.

Context

Creatine monohydrate remains one of the most heavily researched and widely used supplements among strength athletes and recreational lifters. Although its role in improving muscular power and anaerobic performance is well established, evidence for its effect on body composition—particularly when combined with resistance training—has varied. This systematic review sought to clarify whether creatine meaningfully enhances training-induced hypertrophy and whether it affects fat mass.

Methods

Researchers screened 1,694 studies, narrowing to 12 trials (n=362) that met strict inclusion criteria: healthy adults aged 18–50 performing full-body, machine or free-weight resistance training for 4–11 weeks. Participants trained about four days per week at 65–83% of 1RM, averaging 8 exercises per session and roughly 13 weekly sets per muscle group—sufficient for hypertrophic stimulus.

Most studies used a loading phase of 20 g/day (or 0.3 g/kg) for 5–7 days followed by maintenance doses of 5–7 g/day. Some trials added carbohydrate drinks to creatine dosing to test whether insulin-mediated creatine uptake would amplify results. Body composition was measured with high-reliability methods: dual-energy X-ray absorptiometry (DXA), MRI, or CT.

Results

Creatine with resistance training increased lean body mass by 1.14 kg more than training alone (95% CI 0.69–1.59). Training status—novice or experienced—did not affect outcomes, and total training volume showed no moderating influence.

Fat loss was also greater with creatine: body fat percentage dropped by 0.88% and fat mass by 0.73 kg more than in placebo groups. These changes persisted whether or not carbohydrate was co-ingested.

The hypertrophy benefit aligns with previous research showing 0.5–2.0 kg greater lean mass gains from creatine. The fat mass reduction, though smaller in absolute terms, is notable and likely reflects both greater LBM accrual and modest shifts in resting metabolic rate from increased muscle tissue.

Discussion

The findings reaffirm creatine as an effective, low-cost, and safe supplement to enhance RT-driven improvements in lean mass and possibly accelerate fat loss. Mechanistically, creatine’s ergogenic effect stems from increasing phosphocreatine stores, enabling faster ATP resynthesis and allowing greater training intensity and total work output.

The added LBM gain cannot be explained by higher training volume, since all studies equated workloads. Some of the effect may derive from greater cellular hydration—a stimulus for protein synthesis—but long-term hypertrophy likely reflects increased satellite cell activation and myonuclei proliferation.

Adding carbohydrate did not augment outcomes, despite evidence that insulin can enhance creatine uptake into muscle. This suggests the standard monohydrate dose of 5–7 g/day is sufficient on its own when paired with structured resistance training.

A limitation noted was the male-dominant sample (87% male), preventing sex-based analysis. Only one trial involved women exclusively. Future research should better examine how creatine influences hypertrophy, water retention, and hormonal cycles in female athletes.

Takeaways

• Creatine supplementation during resistance training increases lean body mass by about 1.1 kg and reduces fat mass by 0.7 kg more than training alone.
• Results are consistent across trained and untrained lifters and unaffected by total training volume.
• Co-ingesting carbohydrate with creatine offers no additional benefit.
• A daily dose of 5–7 g (or 0.3 g/kg body mass) appears sufficient after an optional short loading phase.
• Gains reflect true hypertrophy rather than transient water retention, though short-term water gain may contribute early in use.
• Research remains limited on female populations.

Source

Desai, I., Wewege, M. A., Jones, M. D., Clifford, B. K., Pandit, A., Kaakoush, N. O., Simar, D., & Hagstrom, A. D. (2024). The effect of creatine supplementation on resistance training–based changes to body composition: A systematic review and meta-analysis. Journal of Strength and Conditioning Research, 38(10), 1813–1821. DOI: 10.1519/JSC.0000000000004862.