Vagal activity and oxygen saturation response to hypoxia: Effects of aerobic fitness and rating of hypoxia tolerance

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15510%2F17%3A73581620" target="_blank" >RIV/61989592:15510/17:73581620 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.5507/ag.2017.014" target="_blank" >http://dx.doi.org/10.5507/ag.2017.014</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5507/ag.2017.014" target="_blank" >10.5507/ag.2017.014</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Vagal activity and oxygen saturation response to hypoxia: Effects of aerobic fitness and rating of hypoxia tolerance

Popis výsledku v původním jazyce

Background: A reduction in the inspired oxygen fraction (FiO2) induces a decline in arterial oxygen saturation (SpO2) and changes of heart rate variability (HRV). It has been shown that SpO2 and HRV responses to similar levels of acute normobaric hypoxia are inter-individual variable. Variable response may be influenced by normoxia reached maximal oxygen uptake (VO2max) value. Objective: The primary aim was to assess HRV and the SpO2 response to hypoxia, and examine the association with normoxic VO2max. Methods: Supine HRV and SpO2 were monitored during normobaric hypoxia (FiO2 = 9.6%) for 10 minutes in 28 subjects, aged 23.7 ± 1.7 years. HRV was evaluated by using both spectral and time domain HRV analysis. Low frequency (LF, 0.05-0.15 Hz) and high frequency (HF, 0.15-0.50 Hz) power together with square root of the mean of the squares of the successive differences (rMSSD) were calculated and transformed by natural logarithm (Ln). Based on the SpO2 in hypoxia, subjects were divided into Resistant (RG, SpO2 ≥ 70.9%, n = 14) and Sensitive (SG, SpO2 &lt; 70.9%, n = 14) groups. Perceived hypoxia tolerance was self-scored on a 4-level scale. Results: VO2max was higher in SG (62.4 ± 7.2 ml ⋅ kg-1 ⋅ min-1) compared with RG (55.5 ± 7.1 ml ⋅ kg-1 ⋅ min-1, p = .017, d = 0.97). A significant relationship (r = -.45, p = .017) between hypoxic-normoxic difference in SpO2 and normoxic VO2max level was found. Vagal activity (Ln rMSSD) was significantly decreased (SG: p &lt; .001, d = 2.64; RG: p &lt; .001, d = 1.22), while sympathetic activity (Ln LF/HF) was relatively increased (p &lt; .001, d = -1.40) in only the SG during hypoxia. Conclusions: Results show that subjects with a higher aerobic capacity exhibited a greater decline in SpO2, accompanied by greater autonomic cardiac disturbances during hypoxia. The SpO2 reduction was associated with perceived hypoxia comfort/discomfort. The hypoxia discomfort state was accompanied by a greater withdrawal in cardiac vagal activity.

Název v anglickém jazyce

Vagal activity and oxygen saturation response to hypoxia: Effects of aerobic fitness and rating of hypoxia tolerance

Popis výsledku anglicky

Background: A reduction in the inspired oxygen fraction (FiO2) induces a decline in arterial oxygen saturation (SpO2) and changes of heart rate variability (HRV). It has been shown that SpO2 and HRV responses to similar levels of acute normobaric hypoxia are inter-individual variable. Variable response may be influenced by normoxia reached maximal oxygen uptake (VO2max) value. Objective: The primary aim was to assess HRV and the SpO2 response to hypoxia, and examine the association with normoxic VO2max. Methods: Supine HRV and SpO2 were monitored during normobaric hypoxia (FiO2 = 9.6%) for 10 minutes in 28 subjects, aged 23.7 ± 1.7 years. HRV was evaluated by using both spectral and time domain HRV analysis. Low frequency (LF, 0.05-0.15 Hz) and high frequency (HF, 0.15-0.50 Hz) power together with square root of the mean of the squares of the successive differences (rMSSD) were calculated and transformed by natural logarithm (Ln). Based on the SpO2 in hypoxia, subjects were divided into Resistant (RG, SpO2 ≥ 70.9%, n = 14) and Sensitive (SG, SpO2 &lt; 70.9%, n = 14) groups. Perceived hypoxia tolerance was self-scored on a 4-level scale. Results: VO2max was higher in SG (62.4 ± 7.2 ml ⋅ kg-1 ⋅ min-1) compared with RG (55.5 ± 7.1 ml ⋅ kg-1 ⋅ min-1, p = .017, d = 0.97). A significant relationship (r = -.45, p = .017) between hypoxic-normoxic difference in SpO2 and normoxic VO2max level was found. Vagal activity (Ln rMSSD) was significantly decreased (SG: p &lt; .001, d = 2.64; RG: p &lt; .001, d = 1.22), while sympathetic activity (Ln LF/HF) was relatively increased (p &lt; .001, d = -1.40) in only the SG during hypoxia. Conclusions: Results show that subjects with a higher aerobic capacity exhibited a greater decline in SpO2, accompanied by greater autonomic cardiac disturbances during hypoxia. The SpO2 reduction was associated with perceived hypoxia comfort/discomfort. The hypoxia discomfort state was accompanied by a greater withdrawal in cardiac vagal activity.

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

30306 - Sport and fitness sciences

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Acta Gymnica

ISSN

2336-4912

e-ISSN

—

Svazek periodika

47

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

10

Strana od-do

112-121

Kód UT WoS článku

—

EID výsledku v databázi Scopus

2-s2.0-85031090221