Trial reportRespiratory physiology & neurobiology2011
Cerebral blood flow and oxygenation at maximal exercise: the effect of clamping carbon dioxide.
Trial report in Respiratory physiology & neurobiology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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.
- A simple method to clamp end-tidal carbon dioxide during rest and exercise.European journal of applied physiology · 2012Trial
- Mechanisms regulating cerebral perfusion during running exercise: Influence of foot strike-induced pulsatility oscillations, COThe Journal of physiology · 2026Article
- Cerebral oxygen extraction across different exercise intensities: Role of arterialExperimental physiology · 2025Article
- Article
- Review
- Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation.Physiological reviews · 2021Review
- Cerebral Oxygenation during Exercise in Patients with Cardiopulmonary Diseases: A Prospective Observational Study.Acta Cardiologica Sinica · 2020Article
- Cardiovascular control during whole body exercise.Journal of applied physiology (Bethesda, Md. : 1985) · 2016Review
- Role of CO2 in the cerebral hyperemic response to incremental normoxic and hyperoxic exercise.Journal of applied physiology (Bethesda, Md. : 1985) · 2016Article
- High-intensity interval exercise and cerebrovascular health: curiosity, cause, and consequence.Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism · 2015Review
- Activation patterns of different brain areas during incremental exercise measured by near-infrared spectroscopy.Experimental brain research · 2015Article
- Skin blood flow influences cerebral oxygenation measured by near-infrared spectroscopy during dynamic exercise.European journal of applied physiology · 2013Article
- Effects of hypoxia on cerebral and muscle haemodynamics during knee extensions in healthy subjects.European journal of applied physiology · 2013Article
- The effect of adding CO2 to hypoxic inspired gas on cerebral blood flow velocity and breathing during incremental exercise.PloS one · 2013Article
- Aging blunts hyperventilation-induced hypocapnia and reduction in cerebral blood flow velocity during maximal exercise.Age (Dordrecht, Netherlands) · 2012Article
- Does cerebral oxygen delivery limit incremental exercise performance?Journal of applied physiology (Bethesda, Md. : 1985) · 2011Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
Abstract
During exercise, as end-tidal carbon dioxide (P(ET)(CO₂)) drops after the respiratory compensation point (RCP), so does cerebral blood flow velocity (CBFv) and cerebral oxygenation. This low-flow, low-oxygenation state may limit work capacity. We hypothesized that by preventing the fall in P(ET)(CO₂) at peak work capacity (W(max)) with a newly designed high-flow, low-resistance rebreathing circuit, we would improve CBFv, cerebral oxygenation, and W(max). Ten cyclists performed two incremental exercise tests, one as control and one with P(ET)(CO₂) constant (clamped) after the RCP. We analyzed , middle cerebral artery CBFv, cerebral oxygenation, and cardiopulmonary measures. At W(max), when we clamped P(ET)(CO₂) (39.7 ± 5.2 mmHg vs. 29.6 ± 4.7 mmHg, P < 0.001), CBFv increased (92.6 ± 15.9 cm/s vs. 73.6 ± 12.5 cm/s, P < 0.001). However, cerebral oxygenation was unchanged (ΔTSI -21.3 ± 13.1% vs. -24.3 ± 8.1%, P = 0.33), and W(max) decreased (380.9 ± 20.4W vs. 405.7 ± 26.8 W, P < 0.001). At W(max), clamping P(ET)(CO₂) increases CBFv, but this does not appear to improve W(max).
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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.