Article

Objective: To examine the effect of different levels of fractional inspired oxygen (FIO2) (15%, 21%, 50%) on peak oxygen consumption (VO2,peak) during arm exercise in persons with spinal cord injury and in able-bodied controls. Design: Case-control study. Setting: University medical center in the Netherlands. Participants: Ten able-bodied controls, 6 persons with paraplegia, and 6 persons with tetraplegia. Interventions: Inspiration of 15%, 21%, and 50% oxygen during a 15-minute period before and during arm exercise. Main Outcome Measures: Oxygen uptake (VO(2)peak, VO(2)peak/kg), power output, ventilation, and base excess. Results: In the able-bodied controls, significant FIO2 dependency was seen in power output, VO(2)peak, and VO(2)peak/kg. Persons with paraplegia showed significant FIO2 dependency in VO2 and VO2/kg. In persons with tetraplegia, no FIO2 dependency was observed; however, VO2, and VO2/kg were significantly higher at 50% than at 15% FIO2. Ventilation and base excess did not change in able-bodied controls or in persons with paraplegia with different levels of FIO2. In persons with tetraplegia, ventilation was significantly higher at 15% than at 50% FIO2, and base excess did not change. No significant interactions between groups and FIO2 were observed. Conclusions: Oxygen consumption during peak arm-cranking, exercise is enhanced with an increased inspiratory oxygen fraction in able-bodied controls as well as in persons with paraplegia and to a lesser extent in persons with tetraplegia, indicating that peak oxygen consumption during arm exercise is limited by oxygen supply rather than by the small muscle mass and related biochemical limitations.

Langue : ANGLAIS