Pre-acclimation to altitude in young adults: choosing a hypoxic pattern at sea level which provokes significant haematological adaptations.
Eur J Appl Physiol
; 122(2): 395-407, 2022 Feb.
Article
em En
| MEDLINE
| ID: mdl-34750724
ABSTRACT
PURPOSE:
This single-blind, repeated measures study evaluated adaptive and maladaptive responses to continuous and intermittent hypoxic patterns in young adults.METHODS:
Changes in haematological profile, stress and cardiac damage were measured in ten healthy young participants during three phases (1) breathing normoxic air (baseline); (2) breathing normoxic air via a mask (Sham-controls); (3) breathing intermittent hypoxia (IH) via a mask, mean peripheral oxygen saturation (SpO2) of 85% ~ 70 min of hypoxia. After a 5-month washout period, participants repeated this three-phase protocol with phase, (4) consisting of continuous hypoxia (CH), mean SpO2 = 85%, ~ 70 min of hypoxia. Measures of the red blood cell count (RBCc), haemoglobin concentration ([Hb]), haematocrit (Hct), percentage of reticulocytes (% Retics), secretory immunoglobulin A (S-IgA), cortisol, cardiac troponin T (cTnT) and the erythropoietic stimulation index (calculated OFF-score) were compared across treatments.RESULTS:
Despite identical hypoxic durations at the same fixed SpO2, no significant effects were observed in either CH or Sham-CH control, compared to baseline. While IH and Sham-IH controls demonstrated significant increases in RBCc; [Hb]; Hct; and the erythropoietic stimulation index. Notably, the % Retics decreased significantly in response to IH (-31.9%) or Sham-IH control (-23.6%), highlighting the importance of including Sham-controls. No difference was observed in S-IgA, cortisol or cTnT.CONCLUSION:
The IH but not CH pattern significantly increased key adaptive haematological responses, without maladaptive increases in S-IgA, cortisol or cTnT, indicating that the IH hypoxic pattern would be the best method to boost haematological profiles prior to ascent to altitude.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Altitude
/
Aclimatação
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Hipóxia
Tipo de estudo:
Clinical_trials
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Guideline
Limite:
Adult
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Female
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Humans
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Male
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article