Evidence map›Paper›PMID 39673565›Full record

Trial reportEuropean journal of applied physiology2025

Efficacy of caffeine as an ergogenic aid in multiple cycling time trials.

Ítalo Vinícius, Cayque Brietzke, Paulo Franco-Alvarenga, Gustavo Vasconcelos, Bryan Saunders, Tony Meireles Santos, Flávio Oliveira Pires

Abstract readRandomized Controlled Trial
PubMed Publisher
In one paragraph

Trial report in European journal of applied physiology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed, 1 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Pooled it
  2. Effects of Caffeine on NFL Combine-Like Tests in Undergraduate Students.International journal of exercise science · 2026
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Ítalo ViníciusExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0002-4599-7559
Cayque BrietzkeExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0002-7557-3140
Paulo Franco-AlvarengaExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0002-0894-786X
Gustavo VasconcelosExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0002-1217-3537
Bryan SaundersApplied Physiology and Nutrition Research Group, School of Physical Education and Sport and Faculty of Medicine, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0003-0995-9077
Tony Meireles SantosExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.ORCID http://orcid.org/0000-0002-5242-0117
Flávio Oliveira PiresExercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil. piresfo@usp.br.ORCID http://orcid.org/0000-0003-4538-1751

Funding

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior #0001Coordenação de Aperfeiçoamento de Pessoal de Nível Superior #310355/2019-2Fundação de Amparo à Pesquisa do Estado de São Paulo #2020_04827-0Fundação de Amparo à Pesquisa do Estado de São Paulo 2021/06836-0Fundação de Amparo à Pesquisa do Estado de São Paulo #2021/07036-7
6 · The paper itself

Abstract

introductionEvidence that caffeine supplementation is effective to improve performance in cycling time trials has been obtained in single rather than multiple time trials. We investigated whether 5 mg.kg

methodsAfter selection of eligible cyclists and familiarization with the TT4km, thirteen well-trained cyclists participated in a balanced placebo-controlled designed with two caffeine sessions (CAF-1 and CAF-2) and a placebo session. In each session, cyclists performed a baseline TT4km before caffeine, and two supplemented TT4km (50 min and 80 min after supplementation). Relative and absolute reliability were obtained through intraclass coefficient correlation and standard error of the measurement (SEM), respectively. The cyclists' performance responses to caffeine were classified as beneficial, unchanged, and adverse by calculating the change between caffeine and placebo relative to SEM.

resultsCaffeine enhanced performance in the first supplemented TT4km in CAF-1 and CAF-2 (0.5% and 1.8%, respectively), although only CAF-2 was significantly different from placebo (p < 0.001). Analysis with grouped data showed good absolute and relative reliability of caffeine effects within and across days. However, analysis of individual data showed that 38% and 31% of the cyclists changed their classification of responsiveness to caffeine between the supplemented trials across days.

conclusionsDespite the good reliability of caffeine to enhance performance in a single TT4km performed within and across days, individual analysis challenged the use of caffeine supplementation protocols based on grouped data.

Indexed as

Athletic PerformanceBicyclingCaffeinePerformance-Enhancing SubstancesAdultHumansMalePhysical EnduranceCaffeinePerformance-Enhancing SubstancesAerobic performanceErgogenic aidReproducibilitySupplementation

Identifiers

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.