Article

Objectives: To clarify (1) differences in cardiovascular response during low-intensity exercise in the upright versus the recumbent position, and (2) whether the oxygen uptake (V?o2) calculated by the American College of Sports Medicine (ACSM) metabolic equation reflects the actual V?o2 at low-intensity testing. Design : Repeated-measures comparison study. Setting: University research laboratory. Participants: Thirty-one healthy, young volunteers (age, 23±2y). Interventions: Not applicable Main Outcome Measures : Blood pressure, rate pressure product (RPP), V?o2, oxygen pulse, carbon dioxide output (V?co2), and ventilatory equivalent (V?e) were measured during graded exercise testing using upright and recumbent cycle ergometers. The estimated V?o 2 was calculated by using the ACSM metabolic equation. Results: Systolic blood pressure, RPP, V?o2, oxygen pulse, V?co 2, and V?e at 15 or 30W were significantly higher in the recumbent position than in the upright one (P<.05), however, no significant differences were observed at 50 and 70W. The estimated V?o2 during exercise was significantly higher than the actual one, at every level of intensity, from 15 to 70W (P<.05). Conclusions: Cardiovascular responses should be carefully monitored even during low-intensity exercise using a recumbent cycle ergometer. The V?o2 estimated using the ACSM metabolic equation did not reflect the actual V?o2 during low-intensity exercise at 70W or less. © 2005 by American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.

Langue : ANGLAIS