Contreras-Briceño, FelipeEspinosa-Ramírez, MaximilianoKeim-Bagnara, VicenteCarreño-Román, MatíasRodríguez-Villagra, RafaelVillegas-Belmar, FernandaViscor Carrasco, GinésGabrielli, LuigiAndía, Marcelo E.Araneda, Oscar F.Hurtado, Daniel E.2022-04-072022-04-072022-03-172075-1729https://hdl.handle.net/2445/184835This study aimed to evaluate if the changes in oxygen saturation levels at intercostal muscles (SmO2-m.intercostales) assessed by near-infrared spectroscopy (NIRS) using a wearable device could determine the respiratory compensation point (RCP) during exercise. Fifteen healthy competitive triathletes (8 male; 29±6 years; height 167.6±25.6 cm; weight 69.2±9.4 kg; V ̇O2-máx 58.4±8.1 mL·kg-1·min-1) were evaluated in a cycle ergometer during the maximal oxygen-uptake test (V ̇O2-máx), while lung ventilation (V ̇E), power output (watts, W) and SmO2-m.intercostales were measured. RCP was determined by visual method (RCPvisual: changes at ventilatory equivalents (V ̇E·V ̇CO2-1, V ̇E·V ̇O2-1) and end-tidal respiratory pressure (PetO2, PetCO2) and NIRS method (RCPNIRS: breakpoint of fall in SmO2-m.intercostales). During exercise, SmO2-m.intercostales decreased continuously showing a higher decrease when V ̇E increased abruptly. A good agreement between methods used to determine RCP was found (visual vs NIRS) at %V ̇O2-máx, V ̇O2, V ̇E, and W (Bland-Altman test). Correlations were found to each parameters analyzed (r=0.854; r=0.865; r=0.981; and r=0,968; respectively. p<0.001 in all variables, Pearson test), with no differences (p<0.001 in all variables, t-student test) between methods used (RCPvisual and RCPNIRS). We concluded that changes at SmO2-m.intercostales measured by NIRS could adequately determine RCP in triathletes.13 p.application/pdfengcc-by (c) Contreras-Briceño, Felipe et al., 2022https://creativecommons.org/licenses/by/4.0/ExerciciMúsculs respiratorisExerciseRespiratory musclesinfo:eu-repo/semantics/article7223222022-04-07info:eu-repo/semantics/openAccess