Oral single-ingredient NR and muscle strength: benefit in low-strength adults is not established
research showsOral single-ingredient NR has not established a strength benefit in ordinary adults with reduced strength. An acute trial in12healthy older men reports a small isometric knee-extension signal(P=.048), but its printed95%CI includes zero and conflicts with that test. Other small grip studies did not demonstrate clear improvement; these findings do not establish zero effect, equivalence or benefit in the intended low-strength population. [S01-S06]
ads claimThese sources do not support converting NAD,muscle mass or fatigue changes into proof of strength improvement. [S01-S06]
Four separate assessment dimensions
| Effect direction and size | E~ for small statistical-convention magnitude,not a validated MCID. S05 CI/P conflict and other nonsignificant findings retained. |
|---|---|
| Evidence certainty | Limited;small samples and reporting/design limitations |
| Applicability | Indirect for ordinary low-strength adults;acute healthy response is not chronic treatment efficacy |
| Safety | Caution |
C,fixed46,zero strong axes;not clinical response probability or formal GRADE
Useful facts when choosing a product
- Single oral NR only; other B3 forms,NMN,NAD+,NRH and combinations are distinct.
- NR chloride confirmed in Martens/Elhassan; other batch salts remain unverified.
- Research doses are not personal dosing instructions.
Chamgap Semantic Classification Code
Permanent code issued
S.nicotinamide-riboside.oral.adults-with-reduced-strength-muscle-strength.improve.placebo-or-matched-careSupplements and nutraceuticals > Nicotinamide riboside > Oral > Adults with reduced strength; muscle strength > Improvement claim > Placebo or study-specific matched care
Technical binding of unchanged ChatGPT C/46, Caution and declared study-specific boundaries. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.
Exact Claim Classification
These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.
| Intervention class | S · Supplement or nutraceutical |
|---|---|
| Canonical ingredient or intervention | Nicotinamide riboside |
| Source or part used | Isolated supplement ingredient; botanical part not applicable; batch/process not verified for all studies |
| Formulation or processing | Single oral NR; confirmed chloride trials separated from unverified salts |
| Route | oral |
| Dose | Study-specific:acute500mg or usually1000mg/day,with escalation in one trial;not dosing advice |
| Duration | About2hours,21days,6weeks,10weeks,26weeks/period;not pooled |
| Population | Intended:reduced-strength adults. Actual:healthy older/young men,Werner syndrome,cancer survivors,MCI |
| Effect or condition | Muscle strength improvement |
| Primary endpoint | Page question:grip and muscle-specific maximal force/torque;separate from registered primary outcomes |
| Comparator | Placebo or matched exercise-only;study-specific |
| Duplicate-detection key | S|nicotinamide-riboside|oral|single-ingredient|adults-with-reduced-strength|muscle-strength|placebo-or-matched-care |
What the research actually shows
# TASK-1020 / R01-060 Research Report
## Thirty-second answer
Oral single-ingredient NR has not established a strength benefit in ordinary adults with reduced strength. An acute trial in12healthy older men reports a small isometric knee-extension signal(P=.048), but its printed95%CI includes zero and conflicts with that test. Other small grip studies did not demonstrate clear improvement; these findings do not establish zero effect, equivalence or benefit in the intended low-strength population. [S01-S06]
**Current assessment C/46; safety Caution; kind S/category sports.** This is a rule-based Chamgap evidence assessment,not a response probability,formal GRADE rating or effect size. It is not copied from the D28 muscle-mass verdict3135. Document quality A means same-author checks,not independent external peer review or journal certification.
Input snapshot:2026-09-16T23:46:14+09:00. Searches took place on2026-09-16 UTC,spanning September16-17 in KST. Evidence cutoff:2026-09-17. All dose descriptions are research exposures.
## 1. Fixed question and actual populations
The intended question concerns **oral single-ingredient NR and muscle strength in adults with reduced strength**. Intended eligibility is not substituted for actual trial selection. Healthy older/young men,Werner syndrome,cancer survivors with prediabetes,and older adults with MCI remain distinct. No included study was verified as treatment of diagnosed B3 deficiency; absence of reporting is not proof of nutritional sufficiency.
NR is not niacin,nicotinamide,NMN,NAD+ or NRH. NR+pterostilbene and NAM+B6 are excluded. Single NR added to matched prescribed exercise is not a multicomponent supplement but estimates an **incremental effect over exercise**. Martens/Elhassan explicitly used NR chloride; unverified salts in other batches remain unknown. Reported salt/product milligrams are not converted to free-NR active milligrams. [S01-S06,S11]
Grip,knee-extension/flexion peak force or torque are separated by test and muscle group. No eligible numerical1RM result was verified in this scope; other tests are not relabeled1RM. Muscle mass,appendicular lean mass,DXA/BIA,FFM percentage,blood NAD,body weight,gait,SPPB,fatigue resistance and torque-development rate are not interchangeable with maximal strength.
## 2. Study-level evidence
SD and SEM follow each original source. Twelve crossover observations percondition do not represent24independent people.
| Study | Actual population and denominator | Intervention and comparator | Strength test | Reported result and information status | |---|---|---|---|---| | Dolopikou2020 (online2019) [S05] | Healthy older men, not selected for diagnosed low strength / 12older+12young men; each contributes both conditions | Single500mg NR vs lactose placebo; about2hours;10days between sessions is washout | Knee-extension isometric90degrees and concentric60degrees/s torque,Nm; separate from fatigue | Older isometric: placebo141+/-8.7 vs NR151+/-11.3 Nm(mean+/-SEM),P=.048. Separate difference column9.6+/-19.3,95%CI-2.7 to21.9 Nm conflicts with P. Older concentric:110+/-7.3 vs121+/-10.9 Nm,P=.113; difference10.4,CI-2.9 to23.7. Young isometric P=.146; concentric P=.230. | | Shoji2025 [S01] | Werner syndrome; FAS baseline right19.6+/-7.5kg(n6),left17.4+/-7.4kg(n5) / 9randomized/safety;6efficacy,5left-hand measurements | NR1000mg/day vs placebo;26weeks perperiod,no washout | One grip attempt perhand,standing where possible; right/left kg kept separate | Right changes NR-0.6+/-2.3 vs placebo-1.2+/-2.7kg,P=.563(n6). Left NR-1.2+/-1.7 vs placebo-0.2+/-2.0kg,P=.505(n5);mean+/-SD. Original paired contrast CI not verified. | | Bhandari2025 (online2024) [S02] | Adult childhood/AYA cancer survivors with prediabetes; not selected for weak grip / 10/10randomized;8exercise-only/9exercise+NR analysed | NR1000mg/day6weeks; both arms prescribed3weekly telehealth resistance sessions | Camry,maximum of3attempts perhand; table reports dominant grip,kg | Median(range) change:exercise2.5(-4.1,10.1)kg,exercise+NR-0.1(-1.7,4.3)kg. Between-group P=.27; within-group P=.48/.81 is not the group contrast. CI not reported. | | Martens2018 [S03] | Healthy adults55-79 / 30randomized24completed; pertest denominator not independently verified | NR chloride500mg twice daily,6weeks percondition vs placebo | Grip kg; maximal-voluntary knee flexion/extension peak torque Nm; rate of torque development separate | Main text reports no overall motor-function benefit; actual location is Supplementary Figure1D/E. Exact values,contrast CI/P were not extracted; bar heights were not guessed. | | Elhassan2019 [S04] | Otherwise healthy men70-80,median age75 / 12people,12percondition; not24independent people | NR chloride1000mg/day21days percondition;21-day washout; placebo | Takei bilateraltriplicate,highest readings; absolute grip,kg | Narrative condition values NR32.5 vs placebo34.7kg,P=.96. Numerical variance/coherent paired CI not verified; relative-grip scaling not substituted for absolute kg. | | Orr2024 (online2023) [S06] | Older adults with MCI,not selected for low grip / Abstract20;flow22 with2pre-treatment MRI exclusions;10/10analysed | Escalation to NR1000mg/day over10-week course vs placebo | Pre/post handheld dynamometry; hand,attemptcount and numeric unit not verified from inaccessible supplement | Main text reports no grip change in either arm. Original Supplementary Table6(DOCX) inaccessible; review-only P=.11 not promoted to verified primary data. SPPB/gait are separate. |
Original locations,identifiers,formulation,co-interventions,nutritional status and analysis populations are linked in `sources.json` and `audits/endpoint_extraction.json`. Hands,kg/Nm,acute/chronic timepoints and medians/means are not pooled.
## 3. Positive and contrary findings
The positive finding is older-men isometric knee extension in S05. It does not extend to concentric strength or young men,and the printed CI/P disagreement remains visible. Human strength research therefore exists,but ordinary low-strength adult efficacy is not established. Hand-specific Werner findings,incremental exercise-trial findings and the available healthy/MCI grip results provide nonsignificant or limiting evidence. Different populations,tests and periods are not combined into repeated same-indication refutation(RX/F) or an exact-zero effect. [S01-S06]
S05 states randomization and double blinding; allocation-concealment implementation and a unique registered primary strength hierarchy were not verified. Rare Werner syndrome recruitment is not judged by an invented feasible sample target; its6/9complete-case efficacy set,left-hand n5,no washout and lack of reported period-adjusted strength analysis are explicit limitations. S02 lacks a supplement placebo and reports8/9completed analyses. Public/academic support,manufacturer products and NR-related author ties are mixed; missing funding information is not I2 independence. [S01-S06]
## 4. Paper versus registered primary outcomes
S01 specifies safety,S02 feasibility,and S06 Statistical analyses specifies MoCA as primary. S03 focuses on safety/NAD and S04 on muscle NAD metabolism/bioenergetics; strength was not verified as their primary endpoint. A unique registered primary among S05 redox/performance measures was not identified. Registry identifiers and access levels are separate:an official page shell is not the full registry. Registration concordance and primary-failure flags were not guessed. [S01-S06]
Song2022/NCT05194397 is a16-week protocol with quadriceps-strength Z-score as planned primary,not a completed numerical effect. NADage/NCT06208527 gait plans and NR-VET/NCT04691986 strength-related plans are not verified outcome results. Failure to retrieve a result does not prove that no unpublished/result-posted data exist anywhere and does not verify current recruitment status. [S07-S09]
## 5. Calculations and rule application
Condition SD=SEM*sqrt(12); average SD=34.932506Nm. The rounded10-Nm contrast gives d_av=0.286266; using the reported9.6Nm gives0.274816. This is not paired-difference d_z and does not invent a within-person correlation. The author's8% is not equated with7.09% from rounded means. With no verified group-level MCID,we apply only the supplied0.2/0.5/0.8 statistical size convention and classify the signal below0.5 as small. That convention does not establish clinical efficacy or C1 exclusion of meaningful benefit. [S05; audits/calculations.json; supplied rubric precedents28,34,43]
A sensitivity reconstruction from rounded Werner mean contrasts,two-sided paired-t P values and n gives approximate CIs of[-1.89,3.09]kg(right) and[-4.80,2.80]kg(left). These are analyst approximations,not original CIs,and assume that each P tests that paired change contrast. They are not period/order-adjusted CIs and do not erase the original-CI information gap.
No normal mean-CI is created from S02 medians/ranges. S03 graph values,S04 unverified variance and S06 inaccessible supplement values are not invented. No pooled estimate,MCID,ARR or NNT is manufactured.
P/R1/I1/E~/B2/CX. The acute older-men paper reports a positive P=.048; it is not erased. Condition SEMs yield d_av=0.286 (0.275 using its reported9.6-Nm contrast). Under supplied precedent28 and the0.5 medium-size convention illustrated at lines574-577, this is a small signal (E~), not failure of a validated clinical MCID. The printed CI/P conflict remains explicit (CX). R1 is the provided code for noncomparable/indirect inconsistency, not certification of a confirmatory trial. The small healthy sample and unreported allocation-concealment implementation support B2; acute follow-up itself is not penalized. Unmodified calculator:C; zero strong axes selects fixed anchor46, no override.
Safety,applicability,effect,certainty and document quality remain distinct. C46 is a **limited current evidence assessment retaining a small reported signal**,not a supplementation recommendation or proof of treatment benefit in low-strength adults. Exact supplied rules and scope limits appear in `audits/grading_audit.json`.
## 6. NUT/R01 extraction and safety
Baseline B3-deficiency criteria,total dietary B3 and concomitant vitamins were mostly unreported/unverified. S05 matched3-day diet records and reported no medication/supplement use but did not diagnose total B3 adequacy. S04 protocol-specific medication/vitamin withholding is not personal treatment advice. Blood/muscle NAD changes remain biochemical outcomes,not strength gains. Unreported salt or active-dose basis is not supplied from another study with the same brand. [S01-S06]
Caution. Small,short trials do not establish long-term safety for all adults. Werner syndrome reports7NR versus12placebo AE occurrences,not participant incidences among the9-person safety cohort. Elhassan reports no clinical AEs in12men over21days percondition. The exercise trial reported mild muscle pain,fatigue and nausea/rash; one MCI participant had severe nausea/heartburn requiring temporary dose reduction. Pregnancy,children,severe liver/kidney disease,long exposure and concomitant-drug safety are not established here. Study doses are not personal dosing or treatment-change instructions. [S01,S02,S04,S06]
A dedicated exhaustive drug-interaction/laboratory-interference review was outside scope. Not searched is not not applicable; no absence-of-interaction or absence-of-interference assurance is made.
## 7. Information states and revision triggers
- S05 printed P=.048 and95%CI-2.7 to21.9 Nm do not align; difference-column dispersion19.3 and model correspondence unresolved -> Both retained; no claim of coherent confirmed clinical efficacy (conflicting). - Full official registry records and Orr Supplementary Table6 not accessible -> Paper and registered hierarchy separated; missing values not invented (inaccessible). - Some pertest denominators,paired CIs,salt/active-dose basis,total B3 intake and co-vitamins unreported or unverified -> No automatic cross-trial substitution (not_reported). - Replicated clinically meaningful strength benefit in ordinary adults with low strength/sarcopenia not established in verified scope -> State indirectness of acute healthy,rare-disease,cancer and MCI samples (not_reported). - Dedicated exhaustive interaction and laboratory-interference review was outside this strength task -> No claim of no interactions or no assay interference (not_searched). - New site ID,slug,URL and first publication time unassigned before technical publication -> Clinical content complete; no deployment or next task performed (not_applicable).
Authenticated S05 corrections/data/model clarification,original registration/supplements,a prespecified strength trial in low-strength adults or a material safety signal can trigger revision while preserving the eventual assigned ID/URL. Current content,grade and safety decisions are complete. These limits are not clinical-reverification or new-value TODOs for the recipient.
## 8. Reuse and publication state
The full3135-record index and originals314/929/1068/3093/3094/3135 did not contain the same independent strength claim. Their source maps/extracts were reused without re-researching,regrading or rewriting completed clinical conclusions. TASK-1019's original unassigned status is historical; the supplied subsequent3135receipt records bilingual publication/display,build,two ledgers,MD and index completion. All27current input members and the exact input archive are preserved. [audits/duplicate_audit.json; inputs/members/17_task1019_deployment_receipt.json]
Result:`completed_with_uncertainty`; publication:`needs_id_assignment`; grading:`calculated_with_provided_rules`; content verification:`completed_with_declared_scope`; document quality:A(same author). ID/slug/URL/first_published_at remain null. No server access,deployment or next task occurred. Clinical content is frozen before transport and is not changed for transmission.
## 9. Traceable sources
- [S01] Shoji et al. (2025). Nicotinamide Riboside Supplementation Benefits in Patients With Werner Syndrome. DOI: 10.1111/acel.70093. https://onlinelibrary.wiley.com/doi/pdfdirect/10.1111/acel.70093 — PDF Table 1 p4, Table 2 p8; Methods 5.3 p17 and 5.6; study flow and safety sections (full_text_and_table_screenshots). - [S02] Bhandari et al. (2025; online 2024). Feasibility of telehealth exercise and nicotinamide riboside supplementation in survivors of childhood cancer at risk for diabetes: A pilot randomized controlled trial. DOI: 10.1002/pbc.31369. https://www.brennerlab.net/files/Bhandari25.pdf — Methods 2.1-2.4 pp2-3; flow/safety p4; Table 2 p6; funding/conflicts pp1,7 (full_text_and_table_screenshot). - [S03] Martens et al. (2018). Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. DOI: 10.1038/s41467-018-03421-7. https://www.nature.com/articles/s41467-018-03421-7 — Main Results and Methods; Supplementary Figure 1D/E (not Supplementary Table 8) (full_text_and_supplement_figure_screenshot). - [S04] Elhassan et al. (2019). Nicotinamide Riboside Augments the Aged Human Skeletal Muscle NAD+ Metabolome and Induces Transcriptomic and Anti-inflammatory Signatures. DOI: 10.1016/j.celrep.2019.07.043. https://www.researchgate.net/publication/335157273_Nicotinamide_Riboside_Augments_the_Aged_Human_Skeletal_Muscle_NAD_Metabolome_and_Induces_Transcriptomic_and_Anti-inflammatory_Signatures — Author-uploaded paper Results grip section (article p1721); STAR Methods hand-held dynamometry and study design; Supplementary Figure S4 caption (author_uploaded_primary_full_text_and_supplement_caption). - [S05] Dolopikou et al. (2020; online 2019). Acute nicotinamide riboside supplementation improves redox homeostasis and exercise performance in old individuals: a double-blind cross-over study. DOI: 10.1007/s00394-019-01919-4. https://www.researchgate.net/publication/330914286_Acute_nicotinamide_riboside_supplementation_improves_redox_homeostasis_and_exercise_performance_in_old_individuals_a_double-blind_cross-over_study — Author-uploaded primary manuscript: Participants, Study design, Supplementation, Muscle strength, Statistical analyses, Table 3 and Performance (author_uploaded_primary_full_text_with_table_text). - [S06] Orr et al. (2024; online 2023). A randomized placebo-controlled trial of nicotinamide riboside in older adults with mild cognitive impairment. DOI: 10.1007/s11357-023-00999-9. https://www.brennerlab.net/wp-content/uploads/2023/12/Orr23.pdf — PDF Methods physical function p6, physical-function results p12; Supplementary Table 6 referenced but DOCX download failed (primary_author_pdf_full_text_supplement_inaccessible). - [S07] Song et al. (2022). Exercise training and NR supplementation to improve muscle mass and fitness in adolescent and young adult hematopoietic cell transplant survivors: a randomized controlled trial. DOI: 10.1186/s12885-022-09845-1. https://link.springer.com/article/10.1186/s12885-022-09845-1 — Protocol design, outcome hierarchy, population and intervention (primary_protocol_reused). - [S08] NADage trial / supplied 3093 source record. DOI: not applicable / not verified. https://clinicaltrials.gov/study/NCT06208527 — Supplied 3093 source extraction; official registry shell (provided_prior_extraction_plus_registry_shell). - [S09] Impacts of Nicotinamide Riboside on Functional Capacity and Muscle Physiology in Older Veterans. DOI: not applicable / not verified. https://clinicaltrials.gov/study/NCT04691986 — Official search title and registry shell; supplied prior trial lead (official_search_snippet_and_registry_shell). - [S10] Prokopidis et al. (2025). The Effect of Nicotinamide Mononucleotide and Riboside on Skeletal Muscle Mass and Function: A Systematic Review and Meta-Analysis. DOI: 10.1002/jcsm.13799. https://onlinelibrary.wiley.com/doi/full/10.1002/jcsm.13799 — Intervention-specific study map and strength outcomes (review_map_only). - [S11] Jensen et al. (2022). A randomized placebo-controlled trial of nicotinamide riboside and pterostilbene supplementation in experimental muscle injury in elderly individuals. DOI: 10.1172/jci.insight.158314. https://insight.jci.org/articles/view/158314 — Supplied original intervention-identity extract (provided_prior_primary_intervention_extract).
Why this is classified as C (46)
P/R1/I1/E~/B2/CX. The acute older-men paper reports a positive P=.048; it is not erased. Condition SEMs yield d_av=0.286 (0.275 using its reported9.6-Nm contrast). Under supplied precedent28 and the0.5 medium-size convention illustrated at lines574-577, this is a small signal (E~), not failure of a validated clinical MCID. The printed CI/P conflict remains explicit (CX). R1 is the provided code for noncomparable/indirect inconsistency, not certification of a confirmatory trial. The small healthy sample and unreported allocation-concealment implementation support B2; acute follow-up itself is not penalized. Unmodified calculator:C; zero strong axes selects fixed anchor46, no override.
Counterpoint. Hand-specific Werner and incremental exercise results are nonsignificant; other verified grip reports do not show clear benefit. Nonsignificance is not zero effect or equivalence. [S01-S06]
Rejudgment record. No independent external consensus; same-author source/numeric checks completed — Supplied rubric and unmodified calculator;P,R1,I1,E~,B2,CX;zero strong axes,C fixed anchor46
| Endpoint | P | Symptom or function itself is the target - including patient reports and performance tests Case application: Functional endpoint P;distinct from ingredient kind S |
| Replication | R1 | Single confirmatory trial Case application: R1 for noncomparable indirect discrepancy under precedent31 |
| Independence | I1 | Mixed funding sources |
| Effect size | E~ | Statistically positive but below the threshold |
| Precision | CX | No pooled confidence interval could be confirmed Case application: CX does not mean no CI printed;it denotes unresolved coherent CI for the key positive test |
Stored derived and displayed grades match; this is not a current recalculation or validity check (C).
Review performed and remaining limitations
Some registry/supplement inaccessible;some salt/nutritional status and coherent CIs unverified
Preliminary RoB 2-informed review — not a complete formal assessment
| Randomization | Randomization/blinding statements checked;S05 concealment implementation unreported |
|---|---|
| Deviations from assigned interventions | S02 has no supplement placebo;actual exercise exposure not assumed identical |
| Missing outcome data | WS6/9,left5;S02analyses8/9;S03pertest n unverified |
| Outcome measurement | Actual grip/knee torque with hand,device,angle/speed distinctions |
| Selection of the reported result | S05 unique registered primary not verified;CI/P conflict explicit;no assumed registry concordance |
Reasons for the certainty judgment — not formal GRADE
| Risk of bias | Small healthy sample and missing concealment implementation;manufacturer support/CI width not double-counted |
|---|---|
| Inconsistency | Different populations,exposures,tests and durations prevent R0/RX pooling |
| Indirectness | Insufficient directness for ordinary low-strength adults |
| Imprecision | A CI is printed but alignment with the positive test is unverified;meaningful benefit not excluded |
| Publication bias | No exhaustive search/test claim;protocol-only records/access gaps retained |
Search scope and limitations. audits/search_log.json;reuse314/929/1068/3093/3094/3135;actual2026-09-16UTC search
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Dolopikou2020 (online2019) | Double-blind randomized crossover | 12older+12young men; each contributes both conditions | Authors declare no conflict of interest on publisher page; verified material did not establish full funding/product-independence, so not assumed I2. | Knee-extension isometric90degrees and concentric60degrees/s torque,Nm; separate from fatigue | Older isometric: placebo141+/-8.7 vs NR151+/-11.3 Nm(mean+/-SEM),P=.048. Separate difference column9.6+/-19.3,95%CI-2.7 to21.9 Nm conflicts with P. Older concentric:110+/-7.3 vs121+/-10.9 Nm,P=.113; difference10.4,CI-2.9 to23.7. Young isometric P=.146; concentric P=.230. | Small acute signal; indirect for low-strength adults. Conflicting statistics preserved, not silently repaired |
| Shoji2025 | Double-blind randomized crossover | 9randomized/safety;6efficacy,5left-hand measurements | Public grants plus ChromaDex NR/placebo support; authors state company no role and no conflicts. Not entirely industry-free evidence. | One grip attempt perhand,standing where possible; right/left kg kept separate | Right changes NR-0.6+/-2.3 vs placebo-1.2+/-2.7kg,P=.563(n6). Left NR-1.2+/-1.7 vs placebo-0.2+/-2.0kg,P=.505(n5);mean+/-SD. Original paired contrast CI not verified. | Direct force outcome but rare-disease population and complete-case analysis limit applicability; nonsignificance is not zero/equivalence |
| Bhandari2025 (online2024) | Randomized parallel common-exercise trial; no supplement placebo | 10/10randomized;8exercise-only/9exercise+NR analysed | NIH K12CA001727; NR supplied by ChromaDex; coauthor Brenner has NR-related commercial interests, as preserved in prior source record. | Camry,maximum of3attempts perhand; table reports dominant grip,kg | Median(range) change:exercise2.5(-4.1,10.1)kg,exercise+NR-0.1(-1.7,4.3)kg. Between-group P=.27; within-group P=.48/.81 is not the group contrast. CI not reported. | Incremental NR over exercise; medians/ranges not recast as means/SDs |
| Martens2018 | Double-blind randomized crossover | 30randomized24completed; pertest denominator not independently verified | NIH/public support and ChromaDex contribution/product; mixed independence. | Grip kg; maximal-voluntary knee flexion/extension peak torque Nm; rate of torque development separate | Main text reports no overall motor-function benefit; actual location is Supplementary Figure1D/E. Exact values,contrast CI/P were not extracted; bar heights were not guessed. | Relevant human function evidence retained; biochemical surrogates do not replace force outcomes |
| Elhassan2019 | Double-blind randomized crossover | 12people,12percondition; not24independent people | Public/academic support and NR manufacturer product; coauthor NR patent/advisory/stock ties declared in primary bibliographic record. | Takei bilateraltriplicate,highest readings; absolute grip,kg | Narrative condition values NR32.5 vs placebo34.7kg,P=.96. Numerical variance/coherent paired CI not verified; relative-grip scaling not substituted for absolute kg. | Nonsignificant; separate from NAD metabolomics. Not a verified deficiency-treatment study |
| Orr2024 (online2023) | Randomized double-blind parallel | Abstract20;flow22 with2pre-treatment MRI exclusions;10/10analysed | NIH/VA and ChromaDex product; coauthor NR intellectual-property/advisory/stock ties declared. | Pre/post handheld dynamometry; hand,attemptcount and numeric unit not verified from inaccessible supplement | Main text reports no grip change in either arm. Original Supplementary Table6(DOCX) inaccessible; review-only P=.11 not promoted to verified primary data. SPPB/gait are separate. | Cognitive primary separated from additional grip outcome; no regrading of3094 |
Receipt — 11 References
Evidence access cutoff: 2026-09-17. Each citation states its actual access level (full-text transcription, abstract, index, or other) and remaining limitations. Bibliographic checking does not certify the study results or treatment efficacy.
Technical integration by: Codex · Evidence date: 2026-09-17 · Corrections: 8
Correction log — 8
Corrections applied to this verdict, in chronological order. Changes are logged, not erased.
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Cite this verdict
[Chamgap] Oral single-ingredient NR and muscle strength: benefit in low-strength adults is not established — Evidence Grade C·46. 11 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/oral-nicotinamide-riboside-low-strength-adults-muscle-strength/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.