{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T06:28:22Z","timestamp":1788330502223,"version":"build-2803163510"},"reference-count":53,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,5,10]],"date-time":"2022-05-10T00:00:00Z","timestamp":1652140800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurosci."],"abstract":"<jats:sec><jats:title>Purpose<\/jats:title><jats:p>Hypobaric hypoxic habitats are currently being touted as a potential solution to minimise decompression procedures in preparation for extra vehicular activities during future space missions. Since astronauts will live in hypoxic environments for the duration of such missions, the present study sought to elucidate the separate and combined effects of inactivity [simulated with the experimental bed rest (BR) model] and hypoxia on sleep characteristics in women.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Twelve women (Age = 27 \u00b1 3 year) took part in three 10-day interventions, in a repeated measures cross-over counterbalanced design: (1) normobaric normoxic BR (NBR), (2) normobaric hypoxic BR (HBR; simulated altitude of 4,000 m), and (3) normobaric hypoxic ambulatory (HAMB; 4,000 m) confinement, during which sleep was assessed on night 1 and night 10 with polysomnography. In addition, one baseline sleep assessment was performed. This baseline assessment, although lacking a confinement aspect, was included statistically as a fourth comparison (i.e., pseudo normobaric normoxic ambulatory; pNAMB) in the present study.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Hypoxia decreased sleep efficiency (<jats:italic>p<\/jats:italic> = 0.019), increased N1% sleep (<jats:italic>p<\/jats:italic> = 0.030), decreased N3 sleep duration (<jats:italic>p<\/jats:italic> = 0.003), and increased apnea hypopnea index (<jats:italic>p<\/jats:italic> &amp;lt; 0.001). BR impaired sleep maintenance, efficiency, and architecture [e.g., N2% sleep increased (<jats:italic>p<\/jats:italic> = 0.033)]. Specifically, for N3% sleep, the effects of partial pressure of oxygen and activity interacted. Hypoxia decreased N3% sleep both when active (pNAMB vs HAMB; <jats:italic>p<\/jats:italic> &amp;lt; 0.001) and inactive (NBR vs HBR; <jats:italic>p<\/jats:italic> = 0.021), however, this decrease was attenuated in the inactive state (\u20133.8%) compared to the active state (\u201310.2%).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>A 10-day exposure to hypoxia and BR negatively impacted sleep on multiple levels as in macrostructure, microstructure and respiratory functioning. Interestingly, hypoxia appeared to have less adverse effects on sleep macrostructure while the participants were inactive (bed ridden) compared to when ambulatory. Data were missing to some extent (i.e., 20.8%). Therefore, multiple imputation was used, and our results should be considered as exploratory.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fnins.2022.852741","type":"journal-article","created":{"date-parts":[[2022,5,10]],"date-time":"2022-05-10T09:45:25Z","timestamp":1652175925000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Adult Female Sleep During Hypoxic Bed Rest"],"prefix":"10.3389","volume":"16","author":[{"given":"Jeroen","family":"Van Cutsem","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathalie","family":"Pattyn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olivier","family":"Mairesse","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B\u00e9r\u00e9nice","family":"Delwiche","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helio","family":"Fernandez Tellez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martine","family":"Van Puyvelde","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilie","family":"Lacroix","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam C.","family":"McDonnell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ola","family":"Eiken","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Igor B.","family":"Mekjavic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2022,5,10]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"233","DOI":"10.1016\/j.resp.2013.05.020","article-title":"Breathing and sleep at high altitude.","volume":"188","author":"Ainslie","year":"2013","journal-title":"Respir. Physiol. Neurobiol."},{"key":"B2","doi-asserted-by":"publisher","first-page":"817","DOI":"10.1164\/ajrccm\/145.4_Pt_1.817","article-title":"Operation Everest II: arterial oxygen saturation and sleep at extreme simulated altitude.","volume":"145","author":"Anholm","year":"1992","journal-title":"Am. Rev. Respir. Dis."},{"key":"B3","doi-asserted-by":"publisher","first-page":"283","DOI":"10.1016\/j.jsmc.2018.04.002","article-title":"Menstrual Cycle Effects on Sleep.","volume":"13","author":"Baker","year":"2018","journal-title":"Sleep Med. Clin."},{"key":"B4","author":"Berry","year":"2015","journal-title":"The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications, Version 2.2"},{"key":"B5","doi-asserted-by":"publisher","first-page":"597","DOI":"10.5664\/jcsm.2172","article-title":"Rules for scoring respiratory events in sleep: update of the 2007 AASM Manual for the Scoring of Sleep and Associated Events. Deliberations of the Sleep Apnea Definitions Task Force of the American Academy of Sleep Medicine.","volume":"8","author":"Berry","year":"2012","journal-title":"J. Clin. Sleep Med."},{"key":"B6","doi-asserted-by":"publisher","first-page":"507","DOI":"10.1113\/jphysiol.1983.sp014906","article-title":"Mechanisms of hypoxia-induced periodic breathing during sleep in humans.","volume":"343","author":"Berssenbrugge","year":"1983","journal-title":"J. Physiol."},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1038\/s41398-019-0510-x","article-title":"The onset of sleep disturbances and their associations with anxiety after acute high-altitude exposure at 3700 m.","volume":"9","author":"Bian","year":"2019","journal-title":"Transl. Psychiatr."},{"key":"B8","doi-asserted-by":"publisher","first-page":"1466","DOI":"10.1152\/japplphysiol.00448.2015","article-title":"Sleep at high altitude: guesses and facts.","volume":"119","author":"Bloch","year":"1985","journal-title":"J. Appl. Physiol."},{"key":"B9","doi-asserted-by":"publisher","first-page":"562","DOI":"10.1164\/rccm.200911-1694OC","article-title":"Nocturnal periodic breathing during acclimatization at very high altitude at Mount Muztagh Ata (7,546 m).","volume":"182","author":"Bloch","year":"2010","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"B10","doi-asserted-by":"publisher","first-page":"469","DOI":"10.1016\/s0031-9384(00)00362-0","article-title":"Relationships between mood states and performances in reaction time, psychomotor ability, and mental efficiency during a 31-day gradual decompression in a hypobaric chamber from sea level to 8848 m equivalent altitude.","volume":"71","author":"Bolmont","year":"2000","journal-title":"Physiol. Behav."},{"key":"B11","doi-asserted-by":"publisher","first-page":"288","DOI":"10.1177\/0748730410374943","article-title":"Sex differences in phase angle of entrainment and melatonin amplitude in humans.","volume":"25","author":"Cain","year":"2011","journal-title":"J. Biol. Rhythms."},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2021.809360","article-title":"The Effect of Chronic Intermittent Hypobaric Hypoxia on Sleep Quality and Melatonin Serum Levels in Chilean Miners.","volume":"12","author":"Calderon-Jofre","year":"2021","journal-title":"Front. Physiol."},{"key":"B13","author":"Carpenter","year":"2008","journal-title":"Missing Data in Clinical Trials \u2014 a Practical Guide."},{"key":"B14","doi-asserted-by":"publisher","first-page":"387","DOI":"10.1053\/smrv.2000.0110","article-title":"Exercise and sleep.","volume":"4","author":"Driver","year":"2000","journal-title":"Sleep Med. Rev."},{"key":"B15","doi-asserted-by":"publisher","first-page":"15602","DOI":"10.1073\/pnas.1010666108","article-title":"Sex difference in the near-24-hour intrinsic period of the human circadian timing system.","volume":"108","author":"Duffy","year":"2011","journal-title":"Proc. Natl. Acad. Sci. U S A."},{"key":"B16","doi-asserted-by":"publisher","first-page":"251","DOI":"10.1113\/jphysiol.1961.sp006806","article-title":"The effect of sympathetic stimulation on carotid nerve activity.","volume":"159","author":"Eyzaguirre","year":"1961","journal-title":"J. Physiol."},{"key":"B17","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1164\/rccm.201403-0598LE","article-title":"Sleep-related periodic breathing does not acclimatize to chronic hypobaric hypoxia.","volume":"190","author":"Fernandez Tellez","year":"2014","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.14814\/phy2.14827","article-title":"Improvements in sleep-disordered breathing during acclimatization to 3800 m and the impact on cognitive function.","volume":"9","author":"Frost","year":"2021","journal-title":"Physiol. Rep."},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2018.00442","article-title":"Indices of Increased Decompression Stress Following Long-Term Bed Rest.","volume":"9","author":"Gennser","year":"2018","journal-title":"Front. Physiol."},{"key":"B20","doi-asserted-by":"publisher","first-page":"257","DOI":"10.1111\/jsr.12380","article-title":"Beta EEG reflects sensory processing in active wakefulness and homeostatic sleep drive in quiet wakefulness.","volume":"25","author":"Gr\u00f8nli","year":"2016","journal-title":"J. Sleep Res."},{"key":"B21","author":"Hair","year":"2018","journal-title":"Multivariate Data Analysis, Eighth Edition."},{"key":"B22","doi-asserted-by":"publisher","first-page":"344","DOI":"10.1016\/j.jsams.2011.02.010","article-title":"Accuracy of four resting metabolic rate prediction equations: effects of sex, body mass index, age, and race\/ethnicity.","volume":"14","author":"Hasson","year":"2011","journal-title":"J. Sci. Med."},{"key":"B23","author":"Heer","year":"2009","journal-title":"Standardization of Bed Rest Study Conditions."},{"key":"B24","doi-asserted-by":"publisher","first-page":"115","DOI":"10.1152\/japplphysiol.00832.2014","article-title":"Periodic breathing in healthy humans at exercise in hypoxia.","volume":"118","author":"Hermand","year":"1985","journal-title":"J. Appl. Physiol."},{"key":"B25","doi-asserted-by":"publisher","first-page":"398","DOI":"10.1159\/000196715","article-title":"Operation Everest one and two. Studies of acclimatization to simulated high altitude.","volume":"64","author":"Houston","year":"1997","journal-title":"Respiration"},{"key":"B26","doi-asserted-by":"publisher","first-page":"148","DOI":"10.1111\/j.1365-2869.2009.00745.x","article-title":"Sleep architecture changes during a trek from 1400 to 5000 m in the Nepal Himalaya.","volume":"19","author":"Johnson","year":"2010","journal-title":"J. Sleep Res."},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/zsaa169","article-title":"Gender differences in nighttime sleep patterns and variability across the adult lifespan: a global-scale wearables study.","volume":"44","author":"Jonasdottir","year":"2021","journal-title":"Sleep"},{"key":"B28","doi-asserted-by":"publisher","first-page":"872","DOI":"10.1080\/10543400903105406","article-title":"Last observation carried forward: a crystal ball?","volume":"19","author":"Kenward","year":"2009","journal-title":"J. Biopharm. Stat."},{"key":"B29","doi-asserted-by":"publisher","first-page":"854","DOI":"10.1111\/sms.12976","article-title":"Sustained sympathetic activity in altitude acclimatizing lowlanders and high-altitude natives.","volume":"28","author":"Lundby","year":"2018","journal-title":"Scand. J. Med. Sci. Sports."},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/zsy206","article-title":"Preparing for Mars: human sleep and performance during a 13 month stay in Antarctica.","volume":"42","author":"Mairesse","year":"2019","journal-title":"Sleep"},{"key":"B31","doi-asserted-by":"publisher","first-page":"941","DOI":"10.1089\/jwh.2014.4914","article-title":"The impact of sex and gender on adaptation to space: executive summary.","volume":"23","author":"Mark","year":"2014","journal-title":"J. Womens Health"},{"key":"B32","doi-asserted-by":"publisher","first-page":"13","DOI":"10.1097\/00003677-200301000-00004","article-title":"Adrenergic contribution during acclimatization to high altitude: perspectives from Pikes Peak.","volume":"31","author":"Mazzeo","year":"2003","journal-title":"Exerc. Sport Sci. Rev."},{"key":"B33","doi-asserted-by":"publisher","first-page":"1250","DOI":"10.1113\/EP087482","article-title":"The LunHab project: muscle and bone alterations in male participants following a 10 day lunar habitat simulation.","volume":"104","author":"McDonnell","year":"2019","journal-title":"Exp. Physiol."},{"key":"B34","doi-asserted-by":"publisher","DOI":"10.14814\/phy2.14413","article-title":"The influence of a sustained 10-day hypoxic bed rest on cartilage biomarkers and subchondral bone in females: the FemHab study.","volume":"8","author":"McDonnell","year":"2020","journal-title":"Physiol. Rep."},{"key":"B35","doi-asserted-by":"publisher","first-page":"37","DOI":"10.1113\/EP087834","article-title":"Do females and males exhibit a similar sarcopenic response as a consequence of normoxic and hypoxic bed rest?","volume":"106","author":"Mekjavic","year":"2021","journal-title":"Exp. Physiol."},{"key":"B36","doi-asserted-by":"publisher","first-page":"858","DOI":"10.1093\/sleep\/20.10.858","article-title":"The effects on human sleep and circadian rhythms of 17 days of continuous bedrest in the absence of daylight.","volume":"20","author":"Monk","year":"1997","journal-title":"Sleep"},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2017.00410","article-title":"Bed Rest and Hypoxic Exposure Affect Sleep Architecture and Breathing Stability.","volume":"8","author":"Morrison","year":"2017","journal-title":"Front. Physiol."},{"key":"B38","doi-asserted-by":"publisher","first-page":"673","DOI":"10.1183\/09031936.00073111","article-title":"Altitude illness is related to low hypoxic chemoresponse and low oxygenation during sleep.","volume":"40","author":"Nespoulet","year":"2012","journal-title":"Eur. Respir. J."},{"key":"B39","doi-asserted-by":"crossref","DOI":"10.1177\/1094428114548590","article-title":"Missing Data: five Practical Guidelines.","volume":"17","author":"Newman","year":"2014","journal-title":"Organ. Res. Methods"},{"key":"B40","author":"Norcross","year":"2005","journal-title":"Evidence Report: Risk of Hypobaric Hypoxia from the Exploration Atmosphere."},{"key":"B41","author":"Norcross","year":"2013","journal-title":"Effects of the 8 psia\/32% O2 Atmosphere on the Human in the Spaceflight Environment."},{"key":"B42","author":"Norcross","year":"2015","journal-title":"Evidence Report: Risk of Hypobaric Hypoxia from the Exploration Atmosphere."},{"key":"B43","doi-asserted-by":"publisher","first-page":"419","DOI":"10.5665\/sleep.1708","article-title":"Effect of short-term acclimatization to high altitude on sleep and nocturnal breathing.","volume":"35","author":"Nussbaumer-Ochsner","year":"2012","journal-title":"Sleep"},{"key":"B44","doi-asserted-by":"publisher","first-page":"788","DOI":"10.1152\/japplphysiol.00606.2016","article-title":"Sleep during an Antarctic summer expedition: new light on \u201cpolar insomnia\u201d.","volume":"22","author":"Pattyn","year":"1985","journal-title":"J. Appl. Physiol."},{"key":"B45","doi-asserted-by":"publisher","first-page":"463","DOI":"10.1016\/0013-4694(75)90188-1","article-title":"Sleep physiology at high altitude.","volume":"38","author":"Reite","year":"1975","journal-title":"Electroencephalogr. Clin. Neurophysiol."},{"key":"B46","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1089\/ham.2009.1099","article-title":"Operation Everest III: COMEX \u201997.","volume":"11","author":"Richalet","year":"2010","journal-title":"High. Alt. Med. Biol."},{"key":"B47","doi-asserted-by":"publisher","first-page":"1973","DOI":"10.1007\/s00421-014-2909-7","article-title":"The separate and combined effects of hypoxia and sustained recumbency\/inactivity on sleep architecture.","volume":"114","author":"Rojc","year":"2014","journal-title":"Eur. J. Appl. Physiol."},{"key":"B48","doi-asserted-by":"publisher","first-page":"260","DOI":"10.1177\/0748730411404677","article-title":"Predominance of distal skin temperature changes at sleep onset across menstrual and circadian phases.","volume":"26","author":"Shechter","year":"2011","journal-title":"J. Biol. Rhythms"},{"key":"B49","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0076945","article-title":"Quantitative changes in the sleep EEG at moderate altitude (1630 m and 2590 m).","volume":"8","author":"Stadelmann","year":"2013","journal-title":"PLoS One."},{"key":"B50","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.b2393","article-title":"Multiple imputation for missing data in epidemiological and clinical research: potential and pitfalls.","volume":"338","author":"Sterne","year":"2009","journal-title":"BMJ"},{"key":"B51","doi-asserted-by":"publisher","first-page":"305","DOI":"10.1580\/1080-6032-020.004.0305","article-title":"Subjective sleep quality alterations at high altitude.","volume":"20","author":"Szymczak","year":"2009","journal-title":"Wilderness Environ. Med."},{"key":"B52","doi-asserted-by":"publisher","first-page":"773","DOI":"10.5665\/sleep.5626","article-title":"Exercise during Short-Term and Long-Term Continuous Exposure to Hypoxia Exacerbates Sleep-Related Periodic Breathing.","volume":"39","author":"Tellez","year":"2016","journal-title":"Sleep."},{"key":"B53","doi-asserted-by":"publisher","first-page":"293","DOI":"10.1093\/sleep\/27.2.293","article-title":"Sleep and reported daytime sleepiness in normal subjects: the Sleep Heart Health Study.","volume":"27","author":"Walsleben","year":"2004","journal-title":"Sleep"}],"container-title":["Frontiers in Neuroscience"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnins.2022.852741\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,5,10]],"date-time":"2022-05-10T09:45:42Z","timestamp":1652175942000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnins.2022.852741\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,5,10]]},"references-count":53,"alternative-id":["10.3389\/fnins.2022.852741"],"URL":"https:\/\/doi.org\/10.3389\/fnins.2022.852741","relation":{},"ISSN":["1662-453X"],"issn-type":[{"value":"1662-453X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,5,10]]},"article-number":"852741"}}