Published in:
Open Access
01-05-2017 | Original Article
Markers of physiological stress during exercise under conditions of normoxia, normobaric hypoxia, hypobaric hypoxia, and genuine high altitude
Authors:
David Richard Woods, John Paul O’Hara, Christopher John Boos, Peter David Hodkinson, Costas Tsakirides, Neil Edward Hill, Darren Jose, Amanda Hawkins, Kelly Phillipson, Antonia Hazlerigg, Nicola Arjomandkhah, Liam Gallagher, David Holdsworth, Mark Cooke, Nicholas Donald Charles Green, Adrian Mellor
Published in:
European Journal of Applied Physiology
|
Issue 5/2017
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Abstract
Purpose
To investigate whether there is a differential response at rest and following exercise to conditions of genuine high altitude (GHA), normobaric hypoxia (NH), hypobaric hypoxia (HH), and normobaric normoxia (NN).
Method
Markers of sympathoadrenal and adrenocortical function [plasma normetanephrine (PNORMET), metanephrine (PMET), cortisol], myocardial injury [highly sensitive cardiac troponin T (hscTnT)], and function [N-terminal brain natriuretic peptide (NT-proBNP)] were evaluated at rest and with exercise under NN, at 3375 m in the Alps (GHA) and at equivalent simulated altitude under NH and HH. Participants cycled for 2 h [15-min warm-up, 105 min at 55% Wmax (maximal workload)] with venous blood samples taken prior (T0), immediately following (T120) and 2-h post-exercise (T240).
Results
Exercise in the three hypoxic environments produced a similar pattern of response with the only difference between environments being in relation to PNORMET. Exercise in NN only induced a rise in PNORMET and PMET.
Conclusion
Biochemical markers that reflect sympathoadrenal, adrenocortical, and myocardial responses to physiological stress demonstrate significant differences in the response to exercise under conditions of normoxia versus hypoxia, while NH and HH appear to induce broadly similar responses to GHA and may, therefore, be reasonable surrogates.