Evidence map›Paper›PMID 33137206›Full record

SynthesisEuropean journal of nutrition2021

CYP1A2 genotype and acute ergogenic effects of caffeine intake on exercise performance: a systematic review.

Jozo Grgic, Craig Pickering, Juan Del Coso, Brad J Schoenfeld, Pavle Mikulic

Abstract readSystematic Review
PubMed Publisher
In one paragraph

Synthesis in European journal of nutrition, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers, 4 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
25citing papers in PubMed, 4 pooled it
2.9field-weighted citation impact, top 9% of its field
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

25 citing papers in PubMed, 4 syntheses or guidelines pooled it, 35 citations in OpenAlex.

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  8. Influence of the CYP1A2 c.European journal of nutrition · 2024
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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

5 authors at 5 institutions in 5 countries.

Jozo GrgicInstitute for Health and Sport (IHES), Victoria University, Melbourne, VIC, Australia. jozo.grgic@live.vu.edu.au.
Craig PickeringInstitute of Coaching and Performance, School of Sport and Wellbeing, University of Central Lancashire, Preston, PR1 2HE, UK.
Juan Del CosoCentre for Sport Studies, Rey Juan Carlos University, Fuenlabrada, Spain.
Brad J SchoenfeldDepartment of Health Sciences, Lehman College, Bronx, NY, USA.
Pavle MikulicFaculty of Kinesiology, University of Zagreb, Zagreb, Croatia.
Lehman College · USUniversidad Rey Juan Carlos · ESUniversity of Central Lancashire · GBUniversity of Zagreb · HRVictoria University · AU

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeTo systematically review studies that examined the influence of the CYP1A2 -163C>A polymorphism on the ergogenic effects of caffeine and to discuss some of the reasons for the discrepancies in findings between the studies.

methodsThis review was performed in accordance with the PRISMA guidelines. The search for studies was performed through nine databases.

resultsSeventeen studies were included in the review. Based on the included studies, it seems that individuals with the AA or AC/CC genotype may experience an increase in performance following caffeine ingestion. Significant differences between genotypes were found in four studies, and all four reported a more favorable response in the AA vs. AC/CC genotype. These results suggest that if there is an actual genotype-related effect of acute caffeine supplementation, it might be in that direction. In the studies that reported such data for aerobic endurance, the findings are specific to male participants performing cycling time trials (distances of ≥ 10 km) and ingesting caffeine 60 min before exercise. For high-intensity exercise, two studies reported that genotype variations determined the response to caffeine ingestion, even though the differences were either small (~ 1 additional repetition in high-load resistance exercise set performed to muscular failure) or inconsistent (i.e., observed only in one out of eight performance tests).

conclusionsCYP1A2 genotype variations may modulate caffeine's ergogenic effects, but the differences between genotypes were small, inconsistent, or limited to specific exercise scenarios. Future studies with larger sample sizes are needed to fully elucidate this research area.

Indexed as

Performance-Enhancing SubstancesCaffeineCytochrome P-450 CYP1A2EatingGenotypeHumansMalePhysical EnduranceCaffeineCYP1A2 protein, humanCytochrome P-450 CYP1A2Performance-Enhancing SubstancesErgogenic aidGeneticsResponsesSupplements

Identifiers

PMID33137206
OpenAlexW3095992491

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.