CHAMGAP
Verdict No. 3119 · Search date 2026-09-16 · Methodology v1.0

Single-ingredient oral ordinary thiamine,
does it really help with Endurance time-trial completion time in trained adults?

30-Second Summary
?
Evidence Grade ? · Safety caution
ChatGPT source review and self-verification · Codex technical integration
The target effect, CI, P value and analyzed denominator are all unverified/null. Indirect numbers are not the primary effect.
Caution. Product-specific oral hydrochloride GI/hypersensitivity information is separate[S09]. Predominantly parenteral reactions are not assigned an oral incidence. An absent UL is not evidence of unlimited safety[S08].
What the
research shows
No directly eligible controlled result was verified within the recorded search and access scope. The current value is ? / score null. This is not a finding of no effect or no human research.
What the
ads claim
A shared B1 label does not justify treating ordinary thiamine, derivatives, combinations and injections as the same efficacy claim.

Four separate assessment dimensions

Effect direction and sizeNo directly eligible controlled result was verified within the recorded search and access scope. The current value is ? / score null. This is not a finding of no effect or no human research.
Evidence certaintyNot graded at stage zero
ApplicabilityThe question remains one sport, one standardized completion endpoint and one principal time. The empirical sport, salt, dose, duration, protocol and time remain unverified because no eligible trial was verified.
SafetyCaution. Product-specific oral hydrochloride GI/hypersensitivity information is separate[S09]. Predominantly parenteral reactions are not assigned an oral incidence. An absent UL is not evidence of unlimited safety[S08].

No directly eligible controlled time-trial result was verified. The supplied current-value rule requires ?/null and six downstream axes unscored. This is not an assertion of no human research, so no_human_study=false. Native null-schema errors and the raw pre-validation B suggestion are retained; B is not adopted.

*

Useful facts when choosing a product

  • Base, hydrochloride and mononitrate remain distinct; no salt-to-base dose conversion was invented.
  • Study exposures are not personal dosing advice or anti-doping clearance.
ID

Chamgap Semantic Classification Code

Permanent code issued

S.thiamine.oral-single-ingredient-form-dose-duration-unverified.trained-adults-endurance-time-trial.improve.placebo-no-added-thiamine-matched-control

Substances > Ordinary thiamine (vitamin B1) > Oral single ingredient with form/dose/duration unverified > Endurance time-trial completion time in trained adults > Improvement > Placebo, no added thiamine or matched control

The current value is ? with a null score. Derivative, combination and time-to-exhaustion results are not treated as a direct ordinary-thiamine time-trial effect. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.

Download semantic index (JSON) · Codebook v1

Exact Claim Classification

These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.

Intervention classS · Supplement or nutraceutical
Canonical ingredient or interventionOrdinary thiamine; base, hydrochloride, mononitrate separately; no derivatives
Source or part usedSingle active manufactured ingredient; actual source unverified
Formulation or processingSingle-ingredient ordinary oral thiamine; exact salt/product unverified
Routeoral
DoseEligible-study dose unverified
DurationEligible-study duration unverified
PopulationTrained adults; actual sport and training qualification to be verified
Effect or conditionImprove standardized endurance time-trial performance
Primary endpointOne fixed-distance or fixed-work endurance completion time; lower is better; exact sport/protocol/principal time unverified
ComparatorPlacebo/no added thiamine/otherwise matched control
Duplicate-detection keyS|thiamine|oral-single-ingredient-form-dose-duration-unverified|trained-adults-definition-unverified|endurance-time-trial-completion-time|placebo-no-added-thiamine-matched-control
01

What the research actually shows

The question remains one sport, one standardized completion endpoint and one principal time. The empirical sport, salt, dose, duration, protocol and time remain unverified because no eligible trial was verified.

02

Why this is classified as ?

No directly eligible controlled time-trial result was verified. The supplied current-value rule requires ?/null and six downstream axes unscored. This is not an assertion of no human research, so no_human_study=false. Native null-schema errors and the raw pre-validation B suggestion are retained; B is not adopted.

Counterpoint. A non-significant P value is not equivalence or proof of no effect. An unknown parenthetical dispersion and absent paired variance cannot supply a fabricated confidence interval.

Rejudgment record. No verified directly eligible result — Supplied current-value rule; native calculator exception retained

Review performed and remaining limitations

Single-assistant self-review within documented scope

The target effect, CI, P value and analyzed denominator are all unverified/null. Indirect numbers are not the primary effect.

Preliminary RoB 2-informed review — not a complete formal assessment
RandomizationUnscored: no directly eligible trial selected
Deviations from assigned interventionsUnscored: no directly eligible trial selected
Missing outcome dataUnscored: no directly eligible trial selected
Outcome measurementUnscored: no directly eligible trial selected
Selection of the reported resultUnscored: no directly eligible trial selected
Reasons for the certainty judgment — not formal GRADE
Risk of biasUnscored; no borrowing from indirect evidence
InconsistencyUnscored; no borrowing from indirect evidence
IndirectnessUnscored; no borrowing from indirect evidence
ImprecisionUnscored; no borrowing from indirect evidence
Publication biasUnscored; no borrowing from indirect evidence

Search scope and limitations. search/web_queries.json; search/native_search_log.json; search/access_log.json

03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Webster 1998 derivative-combination trial in highly trained cyclistsRandomized double-blind counterbalanced crossover study in six highly trained cyclists6 participantsUnverified in the accessed abstract; not directly eligible evidence2,000-m completion time after a 50-km preloadPlacebo 178.2 (8.4) s and combination 170.7 (10.2) s, P=0.58. Parenthetical dispersion and paired variance were unverified; the derivative combination was not scored as ordinary thiamine alone.Excluded from target grading because it used a derivative combination
Webster et al. 1997 TTFD exercise-performance crossover trialRandomized double-blind crossover study in 14 participants14 participantsUnverified in the accessed abstract; not directly eligible evidenceCycling time-trial completion timePlacebo 204.5 (5.5) s and TTFD 200.9 (4.3) s, P=0.61. TTFD is a derivative and the training criterion was unverified, so this was not substituted for ordinary thiamine alone.Excluded because of derivative and population-boundary mismatch
Lee et al. 2023 vitamin-B-complex time-to-exhaustion crossover trialRandomized double-blind crossover study in 32 healthy non-athletes32 crossover participants; not double-counted as 64Company funding, product provision and author conflicts are preserved in the package auditTime to exhaustion, not a time trialThe favorable multinutrient time-to-exhaustion result was not substituted because population, intervention and endpoint differed.Excluded because it was multinutrient, non-athlete and used another endpoint
§

Receipt — 11 References

Evidence access cutoff: 2026-09-16. 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.

Webster (1998). Physiological and performance responses to supplementation with thiamin and pantothenic acid derivatives
checked
Webster et al. (1997). The effect of a thiamin derivative on exercise performance
checked
Suzuki and Itokawa (1996). Effects of thiamine supplementation on exercise-induced fatigue
checked
Choi et al. (2013). The effects of endurance training and thiamine supplementation on anti-fatigue during exercise
checked
Lee et al. (2023). A functional evaluation of anti-fatigue and exercise performance improvement following vitamin B complex supplementation in healthy humans, a randomized double-blind trial
checked
Bautista-Hernández et al. (2008). Effect of Thiamine Pyrophosphate on Levels of Serum Lactate, Maximum Oxygen Consumption and Heart Rate in Athletes Performing Aerobic Activity
checked
Masuda et al. (2015). Effect of thiamin (vitamin B1) on carbohydrate metabolism at rest and during exercise
checked
NIH Office of Dietary Supplements. Thiamin: Health Professional Fact Sheet
checked
Flamingo Pharma UK Ltd. Thiamine Hydrochloride 100 mg Tablets: Summary of Product Characteristics
checked
NICE CG32. Nutrition support for adults
checked
ClinicalTrials.gov NCT05586295
checked
Published as a stage-zero current value. Derivative, combination and time-to-exhaustion results are not substituted for ordinary-thiamine time-trial efficacy.
Technical integration by: Codex · Evidence date: 2026-09-16 · Corrections: none

Cite this verdict

Does oral ordinary thiamine alone shorten endurance time-trial completion time in trained adults? Evidence Grade ? card
[Chamgap] Does oral ordinary thiamine alone shorten endurance time-trial completion time in trained adults? — Evidence Grade ?. 11 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/oral-thiamine-trained-adults-endurance-time-trial/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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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.