Muscle and cerebral oxygenation during exercise in athletes with exercise-induced hypoxemia: A comparison between sea level and acute moderate hypoxia. Issue 6 (2nd July 2020)

• Record Type: Journal Article
• Authors: Raberin, Antoine; Meric, Henri; Mucci, Patrick; Lopez Ayerbe, Jorge; Durand, Fabienne
• Is Part Of: European journal of sport science. Volume 20:Issue 6(2020)
• Page Start: 803
• Page End: 812
• Publication Date: 2020-07-02
• Subjects: Hemoglobin saturation -- aerobic performance -- altitude -- muscle oxygenation -- cerebral oxygenation; Sports sciences -- Periodicals; Sports Medicine -- Periodicals; Exercise -- Periodicals; Sports -- Periodicals; 612
• DOI: 10.1080/17461391.2019.1669717
• Languages: English
• ISSNs: 1746-1391

Abstract

Abstract: The objective of the present study was to evaluate the influence of exercise-induced hypoxemia (EIH) on muscle and cerebral oxygenation responses during maximal exercise in normoxia and in acute moderate hypoxia (fraction of inspired oxygen: 15.3%, 2400 m). EIH was defined as a drop in hemoglobin saturation of at least 4% for at least three consecutive minutes during maximal exercise at sea level. Twenty-five athletes performed incremental treadmill tests to assess maximal oxygen consumption (VO2max ) in normoxia and in hypoxia. Oxygenation of the vastus lateralis muscle and the left prefrontal cortex of the brain was monitored using near-infrared spectroscopy. During the normoxic test, 15 athletes exhibited EIH; they displayed a larger change in muscle levels of oxyhemoglobin (ΔO2 Hb) ( p = 0.04) and a greater change in cerebral levels of deoxyhemoglobin (ΔHHb) ( p = 0.02) than athletes without EIH (NEIH group). During the hypoxic test, muscle ΔO2 Hb was lower in the EIH group than in the NEIH group ( p = 0.03). At VO2max, hypoxia was associated with a smaller cerebral ΔO2 Hb in both groups, and a greater cerebral ΔHHb compared to normoxia in the NEIH group only ( p = 0.02). No intergroup differences in changes in muscle oxygenation were observed. The severity of O2 arterial desaturation was negatively correlated with changes in total muscle hemoglobin in normoxia ( r = −0.48, p = 0.01), and positively correlated with the cerebral ΔHHb in normoxia ( r = 0.45, p = 0.02). The occurrence of EIH at sea level was associated with specific muscle and cerebral oxygenation responses to exercise under both normoxia and moderate hypoxia.