Peter Beek, Maarten Bobbert, Gert de Groot, Peter Hollander, Jos de Koning, Knoek van Soest and Huub Toussaint
Yagesh N. Bhambhani, Robert S. Burnham, Gary D. Wheeler, Peter Eriksson, Leona J. Holland and Robert D. Steadward
In this study we compared the ventilatory threshold (VT) between 8 untrained and 8 endurance-trained males with quadriplegia during simulated wheelchair exercise. Each subject completed an incremental velocity test in his personal wheelchair mounted on a customized roller system designed to provide velocity and distance feedback. VT was identified by two trained evaluators using established respiratory gas exchange criteria. A significant interevaluator reliability coefficient of .90 (p < .01) was observed for the detection of VT. Relative oxygen uptake (V̇O2, ml · kg-1 · min-1) at VT and peak V̇O2 were significantly (p < .05) higher in the endurance-trained compared to untrained subjects. However, no significant difference (p > .05) was observed between the two groups when VT was expressed as a percentage of peak V̇O2. Significant correlations of .86 and .81 (p < .01) were observed between VT and peak V̇O2 in the untrained and trained groups, respectively. It was concluded that endurance training improves both VT and peak V̇O2 during wheelchair exercise in male subjects with quadriplegia but does not improve VT when it is expressed relative to peak V̇O2.
Karin M. Volkers, Tim C.W. van Dijk, Laura H. Eggermont, A. Peter Hollander and Erik J.A. Scherder
The American College of Sports Medicine prescribes regular performance of at least moderate-intensity physical activity for healthy aging. This study examined whether 1 session of 30 min of chair-assisted exercises for the elderly meets this intensity criterion.
This cross-sectional study included 47 cognitively healthy volunteers (mean age 84 years). During the performance of 30 min of chair-assisted exercises the authors determined oxygen uptake (VO2), carbon dioxide production, heart rate (HR), and rating of perceived exertion (RPE). These measures were expressed as a percentage of the estimated maximal VO2 (VO2max) and the estimated maximal HR (HRmax) and estimated as metabolic equivalent units (METs).
Participants performed chair-assisted exercises at 61.0% ± 14.7% of VO2max, 67.6% ± 11.3% HRmax, 3.9 ± 0.9 METs, and 13.1 ± 2.1 RPE.
The intensity of these chair-assisted exercises is at least moderate for older adults, which is necessary for healthy aging.