ArticleJournal of applied physiology (Bethesda, Md. : 1985)2011
Does cerebral oxygen delivery limit incremental exercise performance?
Article in Journal of applied physiology (Bethesda, Md. : 1985), 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 42 papers.
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Who cites it
42 citing papers in PubMed, 86 citations in OpenAlex.
- A simple method to clamp end-tidal carbon dioxide during rest and exercise.European journal of applied physiology · 2012Trial
- Exercise hyperpnoea: Unravelling layers of regulation.The Journal of physiology · 2026Article
- Endurance training induces asymmetric brain oxygenation adaptations in the left and right prefrontal cortex during submaximal exercise.European journal of applied physiology · 2026Article
- Cerebral oxygen extraction across different exercise intensities: Role of arterialExperimental physiology · 2025Article
- Age alters integrated cerebrovascular and cardiovascular dynamic responses to exercise: insights from a systems modeling approach.Journal of applied physiology (Bethesda, Md. : 1985) · 2025Article
- Exercise-induced potentiation of the acute hypoxic ventilatory response: Neural mechanisms and implications for cerebral blood flow.Experimental physiology · 2024Review
- Hemorrhage at high altitude: impact of sustained hypobaric hypoxia on cerebral blood flow, tissue oxygenation, and tolerance to simulated hemorrhage in humans.European journal of applied physiology · 2024Article
- AltitudeOmics: effects of 16 days acclimatization to hypobaric hypoxia on muscle oxygen extraction during incremental exercise.Journal of applied physiology (Bethesda, Md. : 1985) · 2023Article
- Article
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- Hypercapnia elicits differential vascular and blood flow responses in the cerebral circulation and active skeletal muscles in exercising humans.Physiological reports · 2022Article
- Neuromuscular fatigability at high altitude: Lowlanders with acute and chronic exposure, and native highlanders.Acta physiologica (Oxford, England) · 2022Review
- Integrative physiological assessment of cerebral hemodynamics and metabolism in acute ischemic stroke.Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism · 2022Review
- A New Tool for Rapid Assessment of Acute Exercise-Induced Fatigue.Frontiers in human neuroscience · 2022Article
- A comparison of protocols for simulating hemorrhage in humans: step versus ramp lower body negative pressure.Journal of applied physiology (Bethesda, Md. : 1985) · 2021Article
- Cerebrovascular responses to graded exercise in young healthy males and females.Physiological reports · 2020Article
- Measurement and Changes in Cerebral Oxygenation and Blood Flow at Rest and During Exercise in Normotensive and Hypertensive Individuals.Current hypertension reports · 2020Review
- Dynamic cerebral autoregulation across the cardiac cycle during 8 hr of recovery from acute exercise.Physiological reports · 2020Article
- A Comparison of V̇OInternational journal of exercise science · 2020Article
- Pulmonary hemodynamics responses to hypoxia and/or COPflugers Archiv : European journal of physiology · 2018Article
Corrections and comments
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Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
Abstract
Previous studies have suggested that a reduction in cerebral oxygen delivery may limit motor drive, particularly in hypoxic conditions, where oxygen transport is impaired. We hypothesized that raising end-tidal Pco(2) (Pet(CO(2))) during incremental exercise would increase cerebral blood flow (CBF) and oxygen delivery, thereby improving peak power output (W(peak)). Amateur cyclists performed two ramped exercise tests (25 W/min) in a counterbalanced order to compare the normal, poikilocapnic response against a clamped condition, in which Pet(CO(2)) was held at 50 Torr throughout exercise. Tests were performed in normoxia (barometric pressure = 630 mmHg, 1,650 m) and hypoxia (barometric pressure = 425 mmHg, 4,875 m) in a hypobaric chamber. An additional trial in hypoxia investigated effects of clamping at a lower Pet(CO(2)) (40 Torr) from ∼75 to 100% W(peak) to reduce potential influences of respiratory acidosis and muscle fatigue imposed by clamping Pet(CO(2)) at 50 Torr. Metabolic gases, ventilation, middle cerebral artery CBF velocity (transcranial Doppler), forehead pulse oximetry, and cerebral (prefrontal) and muscle (vastus lateralis) hemoglobin oxygenation (near infrared spectroscopy) were monitored across trials. Clamping Pet(CO(2)) at 50 Torr in both normoxia (n = 9) and hypoxia (n = 11) elevated CBF velocity (∼40%) and improved cerebral hemoglobin oxygenation (∼15%), but decreased W(peak) (6%) and peak oxygen consumption (11%). Clamping at 40 Torr near maximal effort in hypoxia (n = 6) also improved cerebral oxygenation (∼15%), but again limited W(peak) (5%). These findings demonstrate that increasing mass cerebral oxygen delivery via CO(2)-mediated vasodilation does not improve incremental exercise performance, at least when accompanied by respiratory acidosis.
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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.