Ageing · CREA-AGE-01 · v2
Across this corpus, giving creatine to older adults alongside resistance or conditioning training tends to improve muscle strength, and the strongest single trial also shows more lean tissue gained than placebo. The clearest evidence comes from two trials that tested creatine on its own [4] and [11], supported by a strength gain from creatine plus training [1]. Other trials mixed creatine with HMB or with L-carnitine and leucine [2] [3], so any benefit there cannot be pinned on creatine itself. One of those combination trials [2] found that muscle-mass changes were not statistically significant and said the strength benefit was independent of muscle mass. The panel treated the direction of effect as consistent but noted small samples, confounded formulas, and that part of one trial's sample was middle-aged rather than older. That mix of coherent support and real caveats is why it landed where it did rather than higher.
The isolated-creatine trials point the same way: [4] reports a greater lean-tissue gain for post-exercise creatine (Δ 3.0 ± 1.9 kg) than placebo (p < 0.025) over 32 weeks in adults 50-71 years, with strength also greater than placebo, and [11] reports creatine raising lean tissue mass, strength, and muscular endurance with and without exercise in adults 45-65 years. [1] adds that strength gains were more visible in the creatine arm than the placebo arm (p < 0/05) after resistance training. The combination trial [3] shows a 1.0 kg increase in total lean muscle mass (P = 0.013) in adults 55-70 years, but creatine is bundled with L-carnitine, leucine, and vitamin D3. [2] improved functional strength yet found within-group body-composition changes not statistically significant. The contested point: The division is whether 'muscle gains' means hypertrophy or strength: [4] and [11] support lean-mass accrual, but [2] explicitly reports non-significant muscle-mass change and attributes its strength benefit to a mechanism independent of muscle mass. The second fault line is attribution, since the trials showing the largest composite or functional gains [2] [3] deliver creatine only inside combined formulas.
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Two included trials ([2], [3]) deliver creatine only within combined formulas (HMB; L-carnitine+leucine+D3), so any muscle gain cannot be attributed to creatine itself; [3]'s L-carnitine-only arm did not move the composite.
[2] explicitly reports that muscle-mass changes were not statistically significant and attributes the functional benefit to a mechanism independent of muscle mass, directly undercutting a hypertrophy reading of 'muscle gains'.
Where it remains uncertain. [2] found muscle-mass changes not statistically significant and called its strength benefit independent of muscle mass, and the combination trials [2] [3] cannot isolate creatine's own contribution.
Aleatory
The isolated-creatine trials [4] [11] have modest group sizes, so observed lean-mass and strength effects carry wide sampling noise, visible in the large standard deviations around [4]'s Δ 3.0 ± 1.9 kg.
The load-bearing papers from a corpus of 11, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Supports enhanced muscular strength gains from creatine added to resistance training in older adults
“although muscle strength changes were more visible in the RT + CS group than in the RT + P group ( p < 0/05)”
Panel auditInternal validity: medium · scope of inference: Non-athlete older men and women (mean 68 years) doing 10 weeks of resistance training, outcome = muscle strength.Key limitations: small groups · strength not mass · short duration
Directionally supportive lean-mass gain, but creatine was delivered in a combination formula and cannot be isolated
“Participants supplemented with the L-Carnitine-combination showed a 1.0 kg increase in total lean muscle mass ( P = 0.013)”
Panel auditInternal validity: medium · scope of inference: Healthy older adults 55-70; outcome = composite lean mass, strength and mobility of a multi-ingredient supplement.Key limitations: three-ingredient combination · creatine not isolated · small arms
Most direct support: isolated creatine+RT over 32 weeks produced greater lean-tissue mass and strength gains than placebo (CR-A Δ3.0 kg vs PLA 0.5 kg, p<0.025)
“Compared with resistance training alone, creatine supplementation improves muscle strength, with greater gains in lean tissue mass resulting from post-exercise creatine supplementation.”
Panel auditInternal validity: high · scope of inference: Older adults 50-71 doing resistance training; outcomes = lean tissue mass and 1RM strength.Key limitations: modest per-group n · between-timing comparison reduces per-cell size
Effect cannot be attributed to creatine because it is co-supplemented with HMB, and within-group muscle-mass changes were non-significant with strength gains stated to be independent of muscle mass.
Panel auditInternal validity: medium · scope of inference: Physically active older adults in a conditioning programme; outcomes = functional strength and body composition.Key limitations: combined creatine + HMB · within-group mass changes non-significant · gains independent of muscle mass
4 of 11 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
A coherent but modest body of primary RCT evidence supports creatine enhancing muscle gains, held below Established by small isolated-creatine samples and confounded combination trials.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
Isolated creatine, older-only, direct mass endpoint. The clearest support mixes a middle-aged sample [11] and a single small isolated trial [4]; a large trial restricted to older adults with DXA lean-mass as a primary endpoint would test the hypertrophy claim directly. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: Adequately powered RCT of creatine alone versus placebo in adults over 65, DXA lean tissue as the primary outcome, with resistance training held constant.
Open question: Does creatine given alone increase lean muscle mass in adults over 65, not just 45-65? Why it is still open: The one isolated trial reporting a lean-mass benefit [4] spans 50-71 and the other [11] is 45-65, so a strictly-older isolated sample is absent.
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 21 Oct 2026 · protocol v0.19