@Article{Sousa2025,
journal="Biology of Sport",
issn="0860-021X",
volume="42",
number="1",
year="2025",
title="Dietary nitrate supplementation very slightly mitigates 
the oxidative stress induced by high-intensity training performed 
in normobaric hypoxia",
abstract="Oxidative stress is augmented under hypoxic environments, which may be attenuated with  antioxidant supplementation. We investigated the effects of dietary nitrate (NO 3 −) supplementation combined with high-intensity training performed under hypoxic conditions on antioxidant/pro-oxidant balance. Thirty trained participants were assigned to one of three groups – HNO: hypoxia (13% F i O 2 ) + NO 3 −; HPL: hypoxia + placebo; CON: normoxia (20.9% Fi O2) + placebo – while performing 12 cycling high-intensity interval training (HIIT) sessions during a 4-week period (3 sessions/week). Before and after the intervention, venous blood samples were collected and a time to exhaustion test (T lim ) was performed (with vastus lateralis changes in local O 2  saturation: SmO 2  monitoring). Glutathione peroxidase (GPX) activity increased in CON ( p  = 0.017, ~20%) and superoxide dismutase (SOD), catalase and ferric-reducing antioxidant power (FRAP) did not change in any group. Malondialdehydes (MDA) increased in both HNO ( p  = 0.001, ~60%) and CON ( p  = 0.023, ~30%) but not in HPL. Advanced oxidation protein products (AOPP), uric acid, and myeloperoxidase activity were not modified by the protocol. Only the CON group recovered faster after the T lim  test (SmO 2recovery :  p  = 0.0003, ~58%). Hypoxic exposure during high-intensity training blunted the increase in GPX and MDA after the intervention period. However, the effects of NO 3 − supplementation seem to very slightly mitigate the detrimental effect of performing high-intensity training under hypoxic conditions.",
author="Sousa, Ana
and Chambion-Diaz, Marie
and Pialoux, Vincent
and Carin, Romain
and Viana, João Luís
and Milheiro, Jaime
and Reis, Víctor Machado
and Millet, Grégoire",
pages="243--251",
doi="10.5114/biolsport.2025.139851",
url="http://dx.doi.org/10.5114/biolsport.2025.139851"
}