Trial reportThe Journal of physiology2008
During hypoxic exercise some vasoconstriction is needed to match O2 delivery with O2 demand at the microcirculatory level.
Trial report in The Journal of physiology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers.
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The trial behind it
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Who cites it
28 citing papers in PubMed, 65 citations in OpenAlex.
- Prolonged adenosine triphosphate infusion and exercise hyperemia in humans.Journal of applied physiology (Bethesda, Md. : 1985) · 2016Trial
- On the mechanisms that limit oxygen uptake during exercise in acute and chronic hypoxia: role of muscle mass.The Journal of physiology · 2009Trial
- The effect of sex on the isolated and combined α- and β-adrenergic control of blood flow during handgrip in adults at high altitude: An exploratory study.Physiological reports · 2026Article
- Global REACH 2018: increased adrenergic restraint of blood flow preserves coupling of oxygen delivery and demand during exercise at high-altitude.The Journal of physiology · 2022Article
- Global Reach 2018: sympathetic neural and hemodynamic responses to submaximal exercise in Andeans with and without chronic mountain sickness.American journal of physiology. Heart and circulatory physiology · 2022Article
- Differences in Cardiac Output and Aerobic Capacity Between Sexes Are Explained by Blood Volume and Oxygen Carrying Capacity.Frontiers in physiology · 2022Article
- Effects of impaired microvascular flow regulation on metabolism-perfusion matching and organ function.Microcirculation (New York, N.Y. : 1994) · 2021Review
- Contribution of oxygen extraction fraction to maximal oxygen uptake in healthy young men.Acta physiologica (Oxford, England) · 2020Review
- Influence of Equimolar Doses of Beetroot Juice and Sodium Nitrate on Time Trial Performance in Handcycling.Nutrients · 2019Article
- Aerobic Capacity, Lactate Concentration, and Work Assessment During Maximum Exercise at Sea Level and High Altitude in Miners Exposed to Chronic Intermittent Hypobaric Hypoxia (3,800 m).Frontiers in physiology · 2019Article
- Regulation of increased blood flow (hyperemia) to muscles during exercise: a hierarchy of competing physiological needs.Physiological reviews · 2015Review
- Maximal heart rate does not limit cardiovascular capacity in healthy humans: insight from right atrial pacing during maximal exercise.The Journal of physiology · 2014Article
- Anti-hypotensive treatment and endothelin blockade synergistically antagonize exercise fatigue in rats under simulated high altitude.PloS one · 2014Article
- Functional sympatholysis and sympathetic escape in a theoretical model for blood flow regulation.Frontiers in physiology · 2014Article
- Skeletal muscle vasodilatation during maximal exercise in health and disease.The Journal of physiology · 2012Review
- Local control of skeletal muscle blood flow during exercise: influence of available oxygen.Journal of applied physiology (Bethesda, Md. : 1985) · 2011Review
- Does cerebral oxygen delivery limit incremental exercise performance?Journal of applied physiology (Bethesda, Md. : 1985) · 2011Article
- Modulation of postjunctional α-adrenergic vasoconstriction during exercise and exogenous ATP infusions in ageing humans.The Journal of physiology · 2011Article
- Vascular adaptations to hypobaric hypoxic training in postmenopausal women.The journal of physiological sciences : JPS · 2011Article
- Article
Corrections and comments
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Authors and funding
6 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
To test the hypothesis that the increased sympathetic tonus elicited by chronic hypoxia is needed to match O(2) delivery with O(2) demand at the microvascular level eight male subjects were investigated at 4559 m altitude during maximal exercise with and without infusion of ATP (80 mug (kg body mass)(-1) min(-1)) into the right femoral artery. Compared to sea level peak leg vascular conductance was reduced by 39% at altitude. However, the infusion of ATP at altitude did not alter femoral vein blood flow (7.6 +/- 1.0 versus 7.9 +/- 1.0 l min(-1)) and femoral arterial oxygen delivery (1.2 +/- 0.2 versus 1.3 +/- 0.2 l min(-1); control and ATP, respectively). Despite the fact that with ATP mean arterial blood pressure decreased (106.9 +/- 14.2 versus 83.3 +/- 16.0 mmHg, P < 0.05), peak cardiac output remained unchanged. Arterial oxygen extraction fraction was reduced from 85.9 +/- 5.3 to 72.0 +/- 10.2% (P < 0.05), and the corresponding venous O(2) content was increased from 25.5 +/- 10.0 to 46.3 +/- 18.5 ml l(-1) (control and ATP, respectively, P < 0.05). With ATP, leg arterial-venous O(2) difference was decreased (P < 0.05) from 139.3 +/- 9.0 to 116.9 +/- 8.4(-1) and leg .VO(2max) was 20% lower compared to the control trial (1.1 +/- 0.2 versus 0.9 +/- 0.1 l min(-1)) (P = 0.069). In summary, at altitude, some degree of vasoconstriction is needed to match O(2) delivery with O(2) demand. Peak cardiac output at altitude is not limited by excessive mean arterial pressure. Exercising leg .VO(2peak) is not limited by restricted vasodilatation in the altitude-acclimatized human.
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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.