Effects of assistive devices on cardiorespiratory demands in older adults

Background and Purpose. The purpose of this study was to quantify and compare cardiorespiratory demands imposed during unassisted ambulation and ambulation with various assistive devices in older adults. Subjects. Ten volunteers (3 male, 7 female) who were not dependent on assistive devices for ambulation, with a mean age 60.3 years (SD=8.4, range=50-74), participated. Methods. Immediately after a 5-minute steady-state session with each of the assistive devices tested (standard walker, wheeled walker, and single-point cane), subjects ambulated for 2 minutes at a self-selected speed with each device and unassisted while selected cardiorespiratory and metabolic variables were monitored. Results. Ambulation with the use of a standard walker was shown to require 212% more oxygen per meter than unassisted ambulation and 104% more oxygen per meter than ambulation with a wheeled walker. Ambulation with a standard walker elicited 200% and 98% higher heart rate per meter as compared with unassisted ambulation and ambulation with a wheeled walker, respectively. No difference was detected for physiologic demands between unassisted ambulation and ambulation with a cane. Conclusion and Discussion. The decision to prescribe a wheeled walker versus a standard walker may be clinically important with patients who have impaired cardiorespiratory systems.