title: Aerobic fitness influences cerebral oxygenation response to maximal exercise in healthy subjects.
abstract: The study examined whether the aerobic fitness level modifies the cerebral oxygenation response to incremental ramp exercise, and more specifically the decline in cerebral oxygenation from heavy exercise up to maximal intensities. 11 untrained (VO2max 47.3±4.0 mL min(-1) kg(-1)) and 13 endurance-trained (VO2max 61.2±8.0 mL min(-1) kg(-1)) healthy men performed a maximal ramp cycle exercise. Left prefrontal cortex oxygenation (ΔHbO2) was monitored by near-infrared spectroscopy. A cerebral oxygenation threshold decline (ThCOx) during exercise was determined. ThCox occurred in all subjects but for higher VO2 (mL min(-1) kg(-1)) in endurance-trained than in untrained subjects (P<0.01). At submaximal exercise intensity corresponding to ThCOx, ΔHbO2 was higher in endurance-trained than in untrained subjects (P<0.05). VO2 at ThCox was related to VO2 at respiratory compensation point (n=24, r=0.93, P<0.001) and to VO2max (n=24, r=0.92, P<0.001). These findings indicate that above the respiratory compensation point the prefrontal O2 demand exceeds the supply in untrained and in endurance-trained subjects. In addition, the occurrence of ThCOx was delayed to higher absolute exercise intensities in endurance-trained in relation with their higher VO2max than untrained men. These results demonstrated that aerobic fitness influences cerebral oxygenation during exercise.
authors.affiliation: Université Lille, Nord de France, Lille, France; UDSL, EA 4488 Activité Physique - Muscle - Santé, Lille, France. Electronic address: oussnina84@yahoo.fr.
authors.forename: Kahina
authors.initials: K
authors.lastname: Oussaidene
authors.affiliation: EA 4532 CIAMS Laboratory, Université Paris Sud, Université d'Orléans, Orléans, France. Electronic address: fabrice.prieur@univ-orleans.fr.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Prieur
authors.affiliation: Université Lille, Nord de France, Lille, France; UDSL, EA 4488 Activité Physique - Muscle - Santé, Lille, France. Electronic address: tagougui_s@yahoo.fr.
authors.forename: Semah
authors.initials: S
authors.lastname: Tagougui
authors.affiliation: Université Lille, Nord de France, Lille, France; UDSL, EA 4488 Activité Physique - Muscle - Santé, Lille, France. Electronic address: abd-elabasset.abaidia@etu.univ-lille2.fr.
authors.forename: Abdelbasset
authors.initials: A
authors.lastname: Abaidia
authors.affiliation: Université Lille, Nord de France, Lille, France; Service d'Exploration Fonctionnelle Respiratoire, Centre Hospitalier Régional Universitaire, Lille, France. Electronic address: regis.matran@univ-lille2.fr.
authors.forename: Regis
authors.initials: R
authors.lastname: Matran
authors.affiliation: Université Lille, Nord de France, Lille, France; UDSL, EA 4488 Activité Physique - Muscle - Santé, Lille, France. Electronic address: patrick.mucci@univ-lille2.fr.
authors.forename: Patrick
authors.initials: P
authors.lastname: Mucci
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared; D055815:Young Adult
keywords: Cerebral deoxygenation; Endurance training; Exhaustive cycle exercise; Near-infrared spectroscopy (NIRS); Ventilatory threshold