REAL

V<sub>E</sub>STPD as a measure of ventilatory acclimatization to hypobaric hypoxia

Loeppky, JA and Sheard, AC and Salgado, RM and Mermier, CM (2016) V<sub>E</sub>STPD as a measure of ventilatory acclimatization to hypobaric hypoxia. Physiology International (Acta Physiologica Hungarica), 103 (3). pp. 377-391. ISSN 2498-602X

[img]
Preview
Text (Article)
2060.103.2016.3.1.pdf

Download (856kB) | Preview
[img]
Preview
Text (Errata)
erratum.pdf

Download (25kB) | Preview

Abstract

This study compared the ventilation response to an incremental ergometer exercise at two altitudes: 633 mmHg (resident altitude = 1,600 m) and following acute decompression to 455 mmHg (≈4,350 m altitude) in eight male cyclists and runners. At 455 mmHg, the V<sub>E</sub>STPD at RER <1.0 was significantly lower and the V<sub>E</sub>BTPS was higher because of higher breathing frequency; at VO<sub>2</sub>max, both V<sub>E</sub>STPD and V<sub>E</sub>BTPS were not significantly different. As percent of VO<sub>2</sub>max, the V<sub>E</sub>BTPS was nearly identical and V<sub>E</sub>STPD was 30% lower throughout the exercise at 455 mmHg. The lower V<sub>E</sub>STPD at lower pressure differs from two classical studies of acclimatized subjects (Silver Hut and OEII), where V<sub>E</sub>STPD at submaximal workloads was maintained or increased above that at sea level. The lower V<sub>E</sub>STPD at 455 mmHg in unacclimatized subjects at submaximal workloads results from acute respiratory alkalosis due to the initial fall in HbO<sub>2</sub> (≈0.17 pHa units), reduction in PACO<sub>2</sub> (≈5 mmHg) and higher PAO<sub>2</sub> throughout the exercise, which are partially pre-established during acclimatization. Regression equations from these studies predict V<sub>E</sub>STPD from VO<sub>2</sub> and P<sub>B</sub> in unacclimatized and acclimatized subjects. The attainment of ventilatory acclimatization to altitude can be estimated from the measured vs. predicted difference in V<sub>E</sub>STPD at low workloads after arrival at altitude.

Item Type: Article
Additional Information: Errata: http://dx.doi.org/10.1556/2060.103.2016.4.002 Loeppky, JA és Sheard, AC és Salgado, RM és Mermier, CM (2016) Erratum to: V<sub>E</sub>STPD as a measure of ventilatory acclimatization to hypobaric hypoxia. Physiology International, 103 (4). 487-. ISSN 2498-602X
Subjects: R Medicine / orvostudomány > R1 Medicine (General) / orvostudomány általában
Depositing User: Ágnes Sallai
Date Deposited: 05 Oct 2016 08:51
Last Modified: 31 Oct 2017 00:15
URI: http://real.mtak.hu/id/eprint/41551

Actions (login required)

Edit Item Edit Item