Effects of Normobaric Hypoxia on Matched-severe Exercise and Power-duration Relationship.
Int J Sports Med
; 42(8): 708-715, 2021 Jun.
Article
em En
| MEDLINE
| ID: mdl-33461230
ABSTRACT
We investigated the effects of hypoxia on matched-severe intensity exercise and on the parameters of the power-duration relationship. Fifteen trained subjects performed in both normoxia and normobaric hypoxia (FiO2=0.13, ~3000 m) a maximal incremental test, a 3 min all-out test (3AOT) and a transition from rest to an exercise performed to exhaustion (Tlim) at the same relative intensity (80%∆). Respiratory and pulmonary gas-exchange variables were continuously measured (K5, Cosmed, Italy). Tlim test's VÌO2 kinetics was calculated using a two-component exponential model. VÌO2max (44.1±5.1 vs. 58.7±6.4 ml.kg-1.min-1, p<0.001) was decreased in hypoxia. In Tlim, time-to-exhaustion sustained was similar (454±130 vs. 484±169 s) despite that VÌO2 kinetics was slower (τ1 31.1±5.8 vs. 21.6±4.7 s, p<0.001) and the amplitude of the VÌO2 slow component lower (12.4±5.4 vs. 20.2±5.7 ml.kg-1.min-1, p<0.05) in hypoxia. CP was reduced (225±35 vs. 270±49 W, p<0.001) but W' was unchanged (11.3±2.9 vs. 11.4±2.7 kJ) in hypoxia. The changes in CP/VÌO2max were positively correlated with changes in W' (r = 0.58, p<0.05). The lower oxygen availability had an impact on aerobic related physiological parameters, but exercise tolerance is similar between hypoxia and normoxia when the relative intensity is matched despite a slower VÌO2 kinetics in hypoxia.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Consumo de Oxigênio
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Exercício Físico
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Tolerância ao Exercício
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Hipóxia
Tipo de estudo:
Prognostic_studies
Limite:
Adult
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Humans
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Male
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article