Creatine + HMB in Older Adults: Can This Duo Calm Oxidative Stress From Training?
Summary
If you're over 60 and training regularly, you already know exercise is one of the best things you can do for your body — but it also generates a burst of "oxidative stress," the same biochemical process implicated in aging, muscle loss, and slower recovery. A new secondary analysis of a Spanish randomized crossover trial asked a specific question: can stacking two popular supplements, creatine monohydrate and calcium HMB (β-hydroxy-β-methylbutyrate), help keep that oxidative stress in check during a structured training program for older adults?
The study followed 30 physically active adults (average age ~63, two-thirds men) through two 6-week phases: one with 3 g/day creatine plus 3 g/day HMB, one with a placebo (inulin fiber), separated by a 3-week washout, all while doing four supervised exercise sessions a week (strength, power, HIIT, balance, and endurance work). Because it was a crossover design, every participant served as their own control — a smart way to boost statistical power in a small sample.
The researchers focused on the body's "master antioxidant" system built around glutathione, tracking oxidized glutathione (GSSG, a marker of stress) and the Glutathione Redox Index (GRI, a measure of overall balance), plus a dozen secondary markers (MDA, protein carbonyls, FRAP, GPx, and composite indices bundling them together).
The headline finding: under placebo, oxidized glutathione (GSSG) rose over the 6-week training block — a plausible sign of accumulating training stress — while under creatine+HMB it stayed essentially flat. The GRI (a "how balanced is your antioxidant system" score) told the same story: it declined under placebo but held steady with supplementation. That's an encouraging pattern. However — and this matters — after the researchers statistically corrected for testing many biomarkers at once (FDR correction), neither result stayed statistically significant. So these are "nominal" or trending signals, not proven effects.
Most other markers (FRAP, GSH, GPx, total thiols, protein carbonyls, and the composite antioxidant/damage/balance indices) showed no meaningful difference between supplement and placebo. One unexpected wrinkle: in men specifically, malondialdehyde (MDA, a marker of fat oxidation/lipid damage) actually went up slightly more with supplementation — a finding the authors call "exploratory" and possibly related to a non-specific lab assay rather than a true biological signal.
Exploratory analyses also found weak statistical links between changes in these redox indices and changes in functional test scores (arm strength, chair-stand speed, overall physical performance) reported in a companion paper from the same research group — hinting redox status and functional gains may be connected, but this needs dedicated confirmation.
What This Means For You
This trial is a companion analysis to a 2025 study from the same team showing that 6 weeks of creatine + HMB alongside structured training improved functional strength measures (gait speed, sit-to-stand, Timed Up and Go, 400-m walk) in the same 30 older adults, with 25–46% gains in several tests. Combined, the two papers suggest a story worth watching: creatine+HMB may support both performance and the underlying redox environment during training — but the redox piece specifically remains unproven at the statistical level used here.
For supplement shoppers: the doses used (3 g/day creatine monohydrate + 3 g/day calcium HMB, taken together once daily, dissolved in yogurt or juice, in the evening) match commonly recommended, well-tolerated amounts already used in sports nutrition and geriatric research — no loading phase was used. Both ingredients are inexpensive, widely available, and have long safety track records; this study reported no adverse events and >95% compliance over 6 weeks. If you're already active and considering a stack for healthy aging, this is reasonable supporting (not conclusive) evidence for combining the two rather than using either alone, particularly if you're pairing it with a structured multicomponent exercise program — the supplements were tested as an adjunct to training, not as a standalone fix.
Who might benefit most: physically active older adults already exercising regularly, since the redox and functional effects were observed on top of a supervised training stimulus, not at rest. Who should be cautious: anyone with kidney disease (creatine warrants medical clearance), and note the trial excluded people with significant cardiometabolic, renal, hepatic, or musculoskeletal disease. This isn't evidence that the stack "reverses aging" or works without exercise — treat marketing claims to that effect skeptically.
Important Considerations
The biggest limitation: neither primary endpoint (GSSG or GRI) survived correction for multiple comparisons, meaning the promising-looking patterns could be chance findings given how many biomarkers were tested. The authors themselves label these effects "nominal" and "exploratory" throughout, and readers should hold the same caution — this is not a confirmed antioxidant benefit.
The sample was small (30 total, only 10 women), so sex-specific findings — including the unexpected MDA increase in men — are statistically fragile and could reflect noise, assay limitations (the TBARS/MDA test used is known to be non-specific), or true biology; the study can't distinguish these. Six weeks is also a short window; whether these redox patterns persist, strengthen, or fade with longer-term use is unknown. The trial measured blood/plasma biomarkers, which reflect systemic redox status, not necessarily what's happening inside working muscle tissue directly. Functional-performance correlations were explicitly exploratory, not efficacy tests — they were pulled from the companion trial as secondary correlations, not independently validated. Finally, this was an academically funded, no-industry-money study, which reduces (but doesn't eliminate) bias concerns, but the relatively short duration and modest size mean it should be viewed as hypothesis-generating rather than definitive. Larger, longer, adequately powered trials with more specific oxidative-damage assays (e.g., F2-isoprostanes instead of TBARS) are needed before drawing firm conclusions. If you have underlying health conditions or take medications, talk to a doctor or pharmacist before starting a creatine/HMB regimen.
Terms Explained
Technical Study Details
Study Design
Total Score
JADAD Quality Assessment評価詳細
Randomization
2 / 2Blinding
2 / 2Dropouts/Withdrawals
0 / 1Study Population
- age ≥ 60 years
- engagement in ≥150 min/week of structured physical activity for ≥6 months
- absence of severe cardiometabolic, renal, hepatic, or musculoskeletal disorders
Interventions
Creatine monohydrate
Treatmentβ-hydroxy-β-methylbutyrate calcium salt (HMB-Ca)
TreatmentPlacebo (inulin)
ControlOutcomes
| Outcome | Type | Effect | p-value |
|---|---|---|---|
| Oxidized glutathione (GSSG) | Primary | - | p=0.039 |
| Glutathione Redox Index (GRI) | Primary | - | <0.05 (raw) |
| Ferric reducing antioxidant power (FRAP) | Secondary | - | - |
| Protein carbonyls | Secondary | - | - |
| Reduced glutathione (GSH) | Secondary | - | - |
| GSH/GSSG ratio | Secondary | - | - |
| Total thiols | Secondary | - | - |
| Reactive oxygen and nitrogen species (ROS/RNS) | Secondary | - | - |
| Glutathione peroxidase (GPx) activity | Secondary | - | - |
| Malondialdehyde (MDA) | Secondary | - | p=0.035 |
| Fluorescent oxidation products (FOPs) | Secondary | - | - |
| Total protein (BSA-equivalent) | Secondary | - | - |
| Antioxidant Capacity Index (ACI) | Secondary | - | - |
| Oxidative Damage Index (ODI) | Secondary | - | - |
| Redox Balance Index (RBI) | Secondary | - | - |
| Short Physical Performance Battery (SPPB) - percent change | Secondary | - | - |
| 30-s arm-curl test - percent change | Secondary | - | - |
| Leg/back dynamometry - percent change | Secondary | - | - |
| 5-repetition chair-stand test - percent change | Secondary | - | - |
Safety
Conclusion
Six weeks of creatine plus HMB supplementation during supervised exercise training was associated with nominal modulation of glutathione-centered redox balance in physically active older adults, primarily by attenuating the placebo-related rise in oxidized glutathione (GSSG) and preserving the Glutathione Redox Index (GRI); however, these effects did not remain significant after FDR correction. A nominal, exploratory increase in malondialdehyde was observed in men under supplementation. Exploratory regression analyses indicated that changes in composite redox indices (particularly GRI, ODI, RBI) weakly co-varied with percent changes in select functional measures (SPPB, arm-curl, leg/back strength), with possible sex-specific patterns, but these associations are hypothesis-generating and require confirmation in larger, adequately powered, longer-duration trials.Limitations
- Sample size, particularly among women (n=10), restricted statistical power for detecting subtle or sex-specific effects
- The six-week intervention duration may not capture longer-term redox or functional adaptations
- Plasma biomarkers reflect systemic, not muscle-specific, redox status
- Small crossover trials may lack sensitivity to detect subtle carryover effects despite formal carryover testing
- The TBARS assay used for MDA is non-specific and susceptible to interference, limiting interpretation of lipid peroxidation results
- FDR correction reduced false positives but the small sample size may have increased the risk of false negatives
- No formal a priori power calculation could be performed for the primary endpoints due to lack of validated within-subject variance estimates; sample size was based on methodological benchmarks and confirmed post-hoc