Presentation Type

Poster

Faculty Mentor’s Full Name

Dustin R. Slivka

Faculty Mentor’s Department

Integrative Physiology and Athletic Training

Abstract / Artist's Statement

To offset sleep disturbances at terrestrial altitude during acclimatization, those at high elevations occasionally use nocturnal oxygen enrichment. However, deliberately dampening the hypoxic stimulus may limit acclimatization. PURPOSE: Determine the impact of nocturnal oxygen enrichment on altitude acclimatization. METHODS: 22 males were assigned to sleep with (O2+, 32.3±2.5% O2) or without (O2-, 20.8±0.1% O2) nocturnal oxygen enrichment. An 8-day acclimatization protocol occurred at a field-based research site with access to sea level (0m), sleeping dormitories (2800m), and a hikeable route to 4200m. Participants were housed at 2800m and completed 5 daily hikes of 10.4±1.2 km with 1371.5±145.1 m of gain. To assess acclimatization, testing occurred on Day 0 at 0m and Days 1, 4, and 7 at 2800m to evaluate vastus lateralis muscle oxygenation (oxygenated hemoglobin, O2Hb; deoxygenated hemoglobin, HHb), arterial oxygen saturation (SPO2), heart rate (HR), and expired gases at rest and during a 5-min cycling bout (1.75 W·kg-1). RESULTS: Total sleep was longer in the O2+ (452±63 min) than the O2- group (427±63, p=0.028). Accordingly, the O2+ group had higher overnight SPO2 (96±1, 91±2%, p-1, p2- group. However, no other group differences were noted at rest, while cycling, or during acclimatization. ∆O2Hb did not differ between the O2+ (-2.2±2.4 A.U.) and O2- groups (-1.6±2.6 A.U., p=0.426). ∆HHb did not differ between the O2+ (4.2±4.8 A.U.) and O2- groups (3.4±3.8 A.U., p=0.643). SPO2 did not differ between the O2+ (91±5%) and O2- groups (91±5%, p=0.416). HR did not differ between the O2+ (86±29 beats·min-1) and O2- groups (91±31 beats·min-1, p=0.744). Respiratory exchange ratio did not differ between the O2+ (0.74±0.27) and O2- groups (0.84±0.08, p=0.360). CONCLUSION: Nocturnal oxygen enrichment during altitude acclimatization promoted longer total sleep but did not hinder short-term acclimatization when partaking in daily prolonged exercise.

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Life Sciences

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Apr 19th, 2:30 PM Apr 19th, 3:30 PM

Impact of Nocturnal Oxygen Enrichment on High Elevation Acclimatization

UC South Ballroom

To offset sleep disturbances at terrestrial altitude during acclimatization, those at high elevations occasionally use nocturnal oxygen enrichment. However, deliberately dampening the hypoxic stimulus may limit acclimatization. PURPOSE: Determine the impact of nocturnal oxygen enrichment on altitude acclimatization. METHODS: 22 males were assigned to sleep with (O2+, 32.3±2.5% O2) or without (O2-, 20.8±0.1% O2) nocturnal oxygen enrichment. An 8-day acclimatization protocol occurred at a field-based research site with access to sea level (0m), sleeping dormitories (2800m), and a hikeable route to 4200m. Participants were housed at 2800m and completed 5 daily hikes of 10.4±1.2 km with 1371.5±145.1 m of gain. To assess acclimatization, testing occurred on Day 0 at 0m and Days 1, 4, and 7 at 2800m to evaluate vastus lateralis muscle oxygenation (oxygenated hemoglobin, O2Hb; deoxygenated hemoglobin, HHb), arterial oxygen saturation (SPO2), heart rate (HR), and expired gases at rest and during a 5-min cycling bout (1.75 W·kg-1). RESULTS: Total sleep was longer in the O2+ (452±63 min) than the O2- group (427±63, p=0.028). Accordingly, the O2+ group had higher overnight SPO2 (96±1, 91±2%, p-1, p2- group. However, no other group differences were noted at rest, while cycling, or during acclimatization. ∆O2Hb did not differ between the O2+ (-2.2±2.4 A.U.) and O2- groups (-1.6±2.6 A.U., p=0.426). ∆HHb did not differ between the O2+ (4.2±4.8 A.U.) and O2- groups (3.4±3.8 A.U., p=0.643). SPO2 did not differ between the O2+ (91±5%) and O2- groups (91±5%, p=0.416). HR did not differ between the O2+ (86±29 beats·min-1) and O2- groups (91±31 beats·min-1, p=0.744). Respiratory exchange ratio did not differ between the O2+ (0.74±0.27) and O2- groups (0.84±0.08, p=0.360). CONCLUSION: Nocturnal oxygen enrichment during altitude acclimatization promoted longer total sleep but did not hinder short-term acclimatization when partaking in daily prolonged exercise.