Hypoxia gradually augments metabolic and thermoperceptual responsiveness to repeated whole-body cold stress in humans
العنوان: | Hypoxia gradually augments metabolic and thermoperceptual responsiveness to repeated whole-body cold stress in humans |
---|---|
المؤلفون: | Keramidas, Michail E., Assistant Professor, Kölegård, Roger, Eiken, Ola |
المصدر: | Experimental Physiology. 105:2123-2140 |
الوصف: | We examined whether hypoxia would modulate thermoeffector responses during repeated cold stress encountered in a single day. Eleven men completed two ∼10 h sessions, while breathing, in normobaria, either normoxia or hypoxia (PO2 : 12 kPa). During each session, subjects underwent sequentially three 120 min immersions to the chest in 20◦C water (CWI), interspersed by 120 min rewarming. In normoxia, the final drop in rectal temperature (Trec) was greater in the third (∼1.2◦C) than in the first and second (∼0.9◦C) CWIs (P < 0.05). The first hypoxic CWI augmented the Trec fall (∼1.2◦C; P = 0.002), but the drop in Trec did not vary between the three hypoxic CWIs (P = 0.99). In normoxia, the metabolic heat production (Ṁ ) was greater during the first half of the third CWI than during the corresponding part of the first CWI (P = 0.02); yet the difference was blunted during the second half of the CWIs (P = 0.89). In hypoxia, by contrast, the increase in Ṁ was augmented by ∼25% throughout the third CWI (P < 0.01). Regardless of the breathing condition, the cold-induced elevation in mean arterial pressure was blunted in the second and third CWI (P < 0.05). Hypoxia aggravated the sensation of coldness (P = 0.05) and thermal discomfort (P = 0.04) during the second half of the third CWI. The present findings therefore demonstrate that prolonged hypoxia mediates, in a gradual manner, metabolic and thermoperceptual sensitization to repeated cold stress. |
وصف الملف: | electronic |
الوصول الحر: | https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284590Test https://doi.org/10.1113/EP089070Test https://kth.diva-portal.org/smash/get/diva2:1484825/FULLTEXT01.pdfTest |
قاعدة البيانات: | SwePub |
ResultId |
1 |
---|---|
Header |
edsswe SwePub edsswe.oai.DiVA.org.kth.284590 925 6 unknown 924.8955078125 |
PLink |
https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&scope=site&db=edsswe&AN=edsswe.oai.DiVA.org.kth.284590&custid=s6537998&authtype=sso |
FullText |
Array
(
[Availability] => 0
)
Array ( [0] => Array ( [Url] => https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284590# [Name] => EDS - SwePub [Category] => fullText [Text] => View record in SwePub [MouseOverText] => View record in SwePub ) ) |
Items |
Array
(
[Name] => Title
[Label] => Title
[Group] => Ti
[Data] => Hypoxia gradually augments metabolic and thermoperceptual responsiveness to repeated whole-body cold stress in humans
)
Array ( [Name] => Author [Label] => Authors [Group] => Au [Data] => <searchLink fieldCode="AR" term="%22Keramidas%2C+Michail+E%2E%2C+Assistant+Professor%22">Keramidas, Michail E., Assistant Professor</searchLink><br /><searchLink fieldCode="AR" term="%22Kölegård%2C+Roger%22">Kölegård, Roger</searchLink><br /><searchLink fieldCode="AR" term="%22Eiken%2C+Ola%22">Eiken, Ola</searchLink> ) Array ( [Name] => TitleSource [Label] => Source [Group] => Src [Data] => <i>Experimental Physiology</i>. 105:2123-2140 ) Array ( [Name] => Abstract [Label] => Description [Group] => Ab [Data] => We examined whether hypoxia would modulate thermoeffector responses during repeated cold stress encountered in a single day. Eleven men completed two ∼10 h sessions, while breathing, in normobaria, either normoxia or hypoxia (PO2 : 12 kPa). During each session, subjects underwent sequentially three 120 min immersions to the chest in 20◦C water (CWI), interspersed by 120 min rewarming. In normoxia, the final drop in rectal temperature (Trec) was greater in the third (∼1.2◦C) than in the first and second (∼0.9◦C) CWIs (P < 0.05). The first hypoxic CWI augmented the Trec fall (∼1.2◦C; P = 0.002), but the drop in Trec did not vary between the three hypoxic CWIs (P = 0.99). In normoxia, the metabolic heat production (Ṁ ) was greater during the first half of the third CWI than during the corresponding part of the first CWI (P = 0.02); yet the difference was blunted during the second half of the CWIs (P = 0.89). In hypoxia, by contrast, the increase in Ṁ was augmented by ∼25% throughout the third CWI (P < 0.01). Regardless of the breathing condition, the cold-induced elevation in mean arterial pressure was blunted in the second and third CWI (P < 0.05). Hypoxia aggravated the sensation of coldness (P = 0.05) and thermal discomfort (P = 0.04) during the second half of the third CWI. The present findings therefore demonstrate that prolonged hypoxia mediates, in a gradual manner, metabolic and thermoperceptual sensitization to repeated cold stress. ) Array ( [Name] => Format [Label] => File Description [Group] => SrcInfo [Data] => electronic ) Array ( [Name] => URL [Label] => Access URL [Group] => URL [Data] => <link linkTarget="URL" linkTerm="https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284590" linkWindow="_blank">https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284590</link><br /><link linkTarget="URL" linkTerm="https://doi.org/10.1113/EP089070" linkWindow="_blank">https://doi.org/10.1113/EP089070</link><br /><link linkTarget="URL" linkTerm="https://kth.diva-portal.org/smash/get/diva2:1484825/FULLTEXT01.pdf" linkWindow="_blank">https://kth.diva-portal.org/smash/get/diva2:1484825/FULLTEXT01.pdf</link> ) |
RecordInfo |
Array
(
[BibEntity] => Array
(
[Identifiers] => Array
(
[0] => Array
(
[Type] => doi
[Value] => 10.1113/EP089070
)
)
[Languages] => Array
(
[0] => Array
(
[Text] => English
)
)
[PhysicalDescription] => Array
(
[Pagination] => Array
(
[PageCount] => 18
[StartPage] => 2123
)
)
[Titles] => Array
(
[0] => Array
(
[TitleFull] => Hypoxia gradually augments metabolic and thermoperceptual responsiveness to repeated whole-body cold stress in humans
[Type] => main
)
)
)
[BibRelationships] => Array
(
[HasContributorRelationships] => Array
(
[0] => Array
(
[PersonEntity] => Array
(
[Name] => Array
(
[NameFull] => Keramidas, Michail E., Assistant Professor
)
)
)
[1] => Array
(
[PersonEntity] => Array
(
[Name] => Array
(
[NameFull] => Kölegård, Roger
)
)
)
[2] => Array
(
[PersonEntity] => Array
(
[Name] => Array
(
[NameFull] => Eiken, Ola
)
)
)
)
[IsPartOfRelationships] => Array
(
[0] => Array
(
[BibEntity] => Array
(
[Dates] => Array
(
[0] => Array
(
[D] => 01
[M] => 01
[Type] => published
[Y] => 2020
)
)
[Identifiers] => Array
(
[0] => Array
(
[Type] => issn-print
[Value] => 09580670
)
[1] => Array
(
[Type] => issn-print
[Value] => 1469445X
)
[2] => Array
(
[Type] => issn-locals
[Value] => swepub_free
)
[3] => Array
(
[Type] => issn-locals
[Value] => KTH_SWEPUB
)
)
[Numbering] => Array
(
[0] => Array
(
[Type] => volume
[Value] => 105
)
)
[Titles] => Array
(
[0] => Array
(
[TitleFull] => Experimental Physiology
[Type] => main
)
)
)
)
)
)
)
|
IllustrationInfo |