Acute Effects of Post-Exercise Hyperoxia on Recovery in Cycling

Inclusion Criteria: * Road cyclists competing in Elite 2 (Elite without professional contract) or Under-23 (U23) categories or equivalent \[Participation in national-level Belgian competitions within the previous 12 months. No specific ranking, finishing position, or performance threshold is required.\] * ≥ 2 consecutive years of cycling experience at regional or national level, with structured and periodized training * Cycling-specific training volume ≥ 8 h a week over the preceding 10 weeks * Stable training load in the weeks preceding inclusion, with no major changes due to injury, illness, or abnormal overload * Measured VO₂max ≥ 60 ml/kg/min Exclusion Criteria: * Presence of significant cardiovascular, pulmonary, neurological, ENT, or metabolic disease, including but not limited to: Uncontrolled arterial hypertension (systolic blood pressure ≥ 180 mmHg and/or diastolic blood pressure ≥ 110 mmHg) ; Unstable heart disease or decompensated cardiomyopathy * Contraindications to hyperbaric exposure, including: Untreated pneumothorax, History of spontaneous pneumothorax without medical clearance ; Pulmonary conditions associated with air trapping (e.g. emphysema or bullous lung disease), or abnormal thoracic imaging when indicated ; Recent thoracic surgery * Neurological contraindications, including epilepsy, history of oxygen-induced seizures, or recent seizure activity, and any association with cannabis use * Ear, sinus, or Eustachian tube disorders preventing adequate pressure equalization, including active infection or history of severe barotrauma * Severe claustrophobia incompatible with chamber exposure