Trial reportThe Journal of physiology2004
Brain and central haemodynamics and oxygenation during maximal exercise in humans.
Trial report in The Journal of physiology, 2004. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 111 papers, 2 of them syntheses that pooled 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.
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.
Brain During Effort : Effects of Hypoxia With Respiratory Patients
Effects of Acute Exercise Intensity on Cerebral Blood Flow and Cognitive Function in Older Adults
Who cites it
111 citing papers in PubMed, 2 syntheses or guidelines pooled it, 272 citations in OpenAlex.
- Core Body Temperatures in Intermittent Sports: A Systematic Review.Sports medicine (Auckland, N.Z.) · 2023Pooled it
- Effects of high intensity interval exercise on cerebrovascular function: A systematic review.PloS one · 2020Pooled it
- Cardiorespiratory and oxygenation responses in iron-deficient anemic women during whole-body exercise under moderate hypoxia.European journal of applied physiology · 2026Trial
- Impact of elevated core temperature on cognition in hot environments within a military context.European journal of applied physiology · 2021Trial
- The effect of severe and moderate hypoxia on exercise at a fixed level of perceived exertion.European journal of applied physiology · 2019Trial
- Plasma Nucleotide Dynamics during Exercise and Recovery in Highly Trained Athletes and Recreationally Active Individuals.BioMed research international · 2018Trial
- The effect of a short-term exercise programme on haemodynamic adaptability; a randomised controlled trial with newly diagnosed transient ischaemic attack patients.Journal of human hypertension · 2013Trial
- Cerebral oxygenation during hyperoxia-induced increase in exercise tolerance for untrained men.European journal of applied physiology · 2013Trial
- Passive heat exposure induced by hot water leg immersion increased oxyhemoglobin in pre-frontal cortex to preserve oxygenation and did not contribute to impaired cognitive functioning.International journal of biometeorology · 2013Trial
- Influence of heat stress and exercise intensity on vastus lateralis muscle and prefrontal cortex oxygenation.European journal of applied physiology · 2013Trial
- Influence of cerebral and muscle oxygenation on repeated-sprint ability.European journal of applied physiology · 2010Trial
- Effects of intermittent hypoxia on SaO(2), cerebral and muscle oxygenation during maximal exercise in athletes with exercise-induced hypoxemia.European journal of applied physiology · 2008Trial
- Effects of heat and cold stress on central vascular pressure relationships during orthostasis in humans.The Journal of physiology · 2007Trial
- Limitations to systemic and locomotor limb muscle oxygen delivery and uptake during maximal exercise in humans.The Journal of physiology · 2005Trial
- Circulating ATP-induced vasodilatation overrides sympathetic vasoconstrictor activity in human skeletal muscle.The Journal of physiology · 2004Trial
- Intracranial vasomotor and blood flow responses to light-intensity aerobic exercise in young adults: a 4D flow MRI study.Journal of applied physiology (Bethesda, Md. : 1985) · 2026Article
- Cerebral oxygenation and skeletal muscle responses to time trial, maximal oxygen uptake and time to exhaustion exercise.Experimental 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
- Increases in skin perfusion and blood oxygen in the non-exercising human limbs during exercise in the heat: Implications for control of circulation.Experimental physiology · 2025Article
- Time-continuous analysis of muscle and cerebral oxygenation during repeated treadmill sprints under heat stress: a statistical parametric mapping study.European journal of applied physiology · 2025Article
51 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
During maximal exercise in humans, fatigue is preceded by reductions in systemic and skeletal muscle blood flow, O(2) delivery and uptake. Here, we examined whether the uptake of O(2) and substrates by the human brain is compromised and whether the fall in stroke volume of the heart underlying the decline in systemic O(2) delivery is related to declining venous return. We measured brain and central haemodynamics and oxygenation in healthy males (n= 13 in 2 studies) performing intense cycling exercise (360 +/- 10 W; mean +/-s.e.m.) to exhaustion starting with either high (H) or normal (control, C) body temperature. Time to exhaustion was shorter in H than in C (5.8 +/- 0.2 versus 7.5 +/- 0.4 min, P < 0.05), despite heart rate reaching similar maximal values. During the first 90 s of both trials, frontal cortex tissue oxygenation and the arterial-internal jugular venous differences (a-v diff) for O(2) and glucose did not change, whereas middle cerebral artery mean flow velocity (MCA V(mean)) and cardiac output increased by approximately 22 and approximately 115%, respectively. Thereafter, brain extraction of O(2), glucose and lactate increased by approximately 45, approximately 55 and approximately 95%, respectively, while frontal cortex tissue oxygenation, MCA V(mean) and cardiac output declined approximately 40, approximately 15 and approximately 10%, respectively. At exhaustion in both trials, systemic VO(2) declined in parallel with a similar fall in stroke volume and central venous pressure; yet the brain uptake of O(2), glucose and lactate increased. In conclusion, the reduction in stroke volume, which underlies the fall in systemic O(2) delivery and uptake before exhaustion, is partly related to reductions in venous return to the heart. Furthermore, fatigue during maximal exercise, with or without heat stress, in healthy humans is associated with an enhanced rather than impaired brain uptake of O(2) and substrates.
Indexed as
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.