Abstract des Autors

Objectives: Conventional wheelchair propulsion is physiologically demanding because of the small muscle mass that is used and the low mechanical efficiency of the movement. Previous research has suggested that a reverse wheeling technique might be more economical than conventional forward wheeling. The present study sought to compare the physiologic demands of forward and reverse wheeling techniques. Design: A repeated measures design was used to compare the dependent variables between forward and reverse wheeling techniques in the same subjects. Setting: Human exercise research laboratory. Participants: Ten able-bodied men. Intervention: Subjects completed graded, discontinuous exercise tests on a wheelchair ergometer, using both forward and reverse wheeling techniques. Main Outcome Measures: Oxygen uptake (VO2), ventilation (VE), and heart rate were measured during the last 30 seconds of each 3-minute exercise stage. Blood lactate concentration ([La]) and rating of perceived exertion (RPE) were determined immediately after each stage. Results: Repeated measures analysis of variance demonstrated that VO2, VE, heart rate, [La], and RPE were all significantly greater (p<.05) with reverse wheeling compared with forward wheeling. VO2 values with reverse wheeling averaged 9% higher than forward wheeling at identical power outputs. Conclusions: Reverse wheelchair propulsion is physiologically more demanding than conventional forward wheelchair propulsion and does not appear to offer potential for improving the economy of wheelchair propulsion. Verf.-Referat