ArticleISRN nutrition2013
Likely additive ergogenic effects of combined preexercise dietary nitrate and caffeine ingestion in trained cyclists.
Article in ISRN nutrition, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 6 of them syntheses that pooled it.
What it found
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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.
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.
Who cites it
16 citing papers in PubMed, 6 syntheses or guidelines pooled it, 24 citations in OpenAlex.
- Ergogenic effects of supplement combinations on endurance performance: a systematic review and meta-analysis of randomized controlled trials.Journal of the International Society of Sports Nutrition · 2025Pooled it
- Effect of Caffeine and Nitrates Combination on Exercise Performance, Heart Rate and Oxygen Uptake: A Systematic Review and Meta-Analysis.Nutrients · 2024Pooled it
- Effect of food sources of nitrate, polyphenols, L-arginine and L-citrulline on endurance exercise performance: a systematic review and meta-analysis of randomised controlled trials.Journal of the International Society of Sports Nutrition · 2021Pooled it
- Ergogenic Effect of Nitrate Supplementation: A Systematic Review and Meta-analysis.Medicine and science in sports and exercise · 2020Pooled it
- The Effect of Dietary Nitrate Supplementation on Endurance Exercise Performance in Healthy Adults: A Systematic Review and Meta-Analysis.Sports medicine (Auckland, N.Z.) · 2017Pooled it
- Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review.Nutrients · 2017Pooled it
- Effects of Dietary Nitrate and Caffeine on End Power and Work Above End Power During a 3 min All-Out Test in Trained Male Cyclists.Nutrients · 2026Trial
- Single and combined effect of beetroot juice and caffeine intake on muscular strength, power and endurance performance in resistance-trained males.Scientific reports · 2025Trial
- Effects of Beetroot Juice Supplementation on a 30-s High-Intensity Inertial Cycle Ergometer Test.Nutrients · 2017Trial
- Exploring saliva as a biofluid for biomonitoring of diet-related contaminants exposure: insights from a literature mining approach.Journal of exposure science & environmental epidemiology · 2026Review
- Influence of Consumption of Nitrate-rich Beetroot Juice on Lactate Production in Saliva and Oral Biofilm - A Clinical Trial.Oral health & preventive dentistry · 2023Article
- Acute effects of beetroot juice and caffeine co-ingestion during a team-sport-specific intermittent exercise test in semi-professional soccer players: a randomized, double-blind, placebo-controlled study.BMC sports science, medicine & rehabilitation · 2022Article
- Carbohydrate supplementation: a critical review of recent innovations.European journal of applied physiology · 2021Review
- Article
- Effects of beetroot juice supplementation on intermittent high-intensity exercise efforts.Journal of the International Society of Sports Nutrition · 2018Review
- Pre-exercise nutrition: the role of macronutrients, modified starches and supplements on metabolism and endurance performance.Nutrients · 2014Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Aims. To evaluate the possible additive effects of beetroot juice plus caffeine on exercise performance. Methods. In a randomized, double-blinded study design, fourteen healthy well-trained men aged 22 ± 3 years performed four trials on different occasions following preexercise ingestion of placebo (PLA), PLA plus 5 mg/kg caffeine (PLA+C), beetroot juice providing 8 mmol of nitrate (BR), and beetroot juice plus caffeine (BR+C). Participants cycled at 60% maximal oxygen uptake ([Formula: see text]max) for 30 min followed by a time to exhaustion (TTE) trial at 80% [Formula: see text]max. Saliva was collected before supplement ingestion, before exercise, and after the TTE trial for salivary nitrate, nitrite, and cortisol analysis. Results. In beetroot trials, saliva nitrate and nitrite increased >10-fold before exercise compared with preingestion (P ≤ 0.002). TTE in BR+C was 46% higher than in PLA (P = 0.096) and 18% and 27% nonsignificant TTE improvements were observed on BR+C compared with BR and PLA+C alone, respectively. Lower ratings of perceived exertion during TTE were found during 80% [Formula: see text]max on BR+C compared with PLA and PLA+C (P < 0.05 for both). Conclusions. Acute preexercise beetroot juice coingestion with caffeine likely has additive effects on exercise performance compared with either beetroot or caffeine alone.
Identifiers
What OpenQuestion holds
Registered trials
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.