The ventilatory effects of sustained isocapnic hypoxia during exercise in humans.
To investigate how the ventilatory response to isocapnic hypoxia is modified by steady-state exercise, five subjects were studied at rest and performing 70 W bicycle exercise. At rest, isocapnic hypoxia (end-tidal PO2 50 Torr) for 25 min resulted in a biphasic response: an initial increase in ventil...
| Main Authors: | , |
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| Format: | Journal article |
| Language: | English |
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1991
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| _version_ | 1826274624212566016 |
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| author | Pandit, J Robbins, P |
| author_facet | Pandit, J Robbins, P |
| author_sort | Pandit, J |
| collection | OXFORD |
| description | To investigate how the ventilatory response to isocapnic hypoxia is modified by steady-state exercise, five subjects were studied at rest and performing 70 W bicycle exercise. At rest, isocapnic hypoxia (end-tidal PO2 50 Torr) for 25 min resulted in a biphasic response: an initial increase in ventilation was followed by a subsequent decline (HVD). During exercise, an end-tidal PO2 of 55-60 Torr was used. The magnitude of the initial ventilatory response to isocapnic hypoxia was increased from a mean +/ SE of 1.43 +/- 0.323 L/min per % arterial desaturation at rest to 2.41 +/- 0.424 L/min per % during exercise (P less than 0.05), but the magnitude of the HVD was reduced from 0.851 +/- 0.149 L/min per % at rest to 0.497 +/- 0.082 L/min per % during exercise (P less than 0.05). The ratio of HVD to the acute hypoxia response was reduced from 0.696 +/- 0.124 at rest to 0.202 +/- 0.029 during exercise (P less than 0.01). We conclude that while exercise augments the ventilatory sensitivity to hypoxia, it also has a direct effect on the mechanisms by which sustained hypoxia depresses peripheral chemosensitivity. |
| first_indexed | 2024-03-06T22:46:16Z |
| format | Journal article |
| id | oxford-uuid:5d498a61-162b-4601-8928-43272b02db4e |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T22:46:16Z |
| publishDate | 1991 |
| record_format | dspace |
| spelling | oxford-uuid:5d498a61-162b-4601-8928-43272b02db4e2022-03-26T17:33:26ZThe ventilatory effects of sustained isocapnic hypoxia during exercise in humans.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5d498a61-162b-4601-8928-43272b02db4eEnglishSymplectic Elements at Oxford1991Pandit, JRobbins, PTo investigate how the ventilatory response to isocapnic hypoxia is modified by steady-state exercise, five subjects were studied at rest and performing 70 W bicycle exercise. At rest, isocapnic hypoxia (end-tidal PO2 50 Torr) for 25 min resulted in a biphasic response: an initial increase in ventilation was followed by a subsequent decline (HVD). During exercise, an end-tidal PO2 of 55-60 Torr was used. The magnitude of the initial ventilatory response to isocapnic hypoxia was increased from a mean +/ SE of 1.43 +/- 0.323 L/min per % arterial desaturation at rest to 2.41 +/- 0.424 L/min per % during exercise (P less than 0.05), but the magnitude of the HVD was reduced from 0.851 +/- 0.149 L/min per % at rest to 0.497 +/- 0.082 L/min per % during exercise (P less than 0.05). The ratio of HVD to the acute hypoxia response was reduced from 0.696 +/- 0.124 at rest to 0.202 +/- 0.029 during exercise (P less than 0.01). We conclude that while exercise augments the ventilatory sensitivity to hypoxia, it also has a direct effect on the mechanisms by which sustained hypoxia depresses peripheral chemosensitivity. |
| spellingShingle | Pandit, J Robbins, P The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title | The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title_full | The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title_fullStr | The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title_full_unstemmed | The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title_short | The ventilatory effects of sustained isocapnic hypoxia during exercise in humans. |
| title_sort | ventilatory effects of sustained isocapnic hypoxia during exercise in humans |
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