Feasibility and validity of a graded one-legged cycle exercise test to determine peak aerobic capacity in older people with a lower-limb amputation.

BACKGROUND: Information concerning exercise tolerance and aerobic capacity is imperative for generating effective and safe exercise programs. However, for older people with a lower-limb amputation, a standard exercise test is not available.

OBJECTIVE: The primary aim of the present study was to determine whether a graded 1-legged peak exercise test is feasible and provides a valid assessment of peak aerobic capacity in older people walking with a lower-limb prosthesis.

DESIGN: This was a quasi-experimental case-control study.

METHODS: A total of 36 older people with a lower-limb prosthesis and 21 people who were able-bodied (controls) (overall mean age=61.7 years, SD=6.1) performed a discontinuous graded 1-legged exercise test. The peak respiratory exchange ratio was used as an indicator of maximal effort. The controls performed an additional 2-legged exercise test to provide insight into differences between the testing modes.

RESULTS: All participants were able to perform the exercise test. Electrocardiographic tracings and blood pressure were adequately monitored. The controls and the people with a lower-limb amputation were able to stress the cardiovascular system to a similar extent. Analyses of construct validity revealed that the peak aerobic capacity measured with the 1-legged exercise test was able to distinguish between participants on the basis of age, body mass index, and sex to a similar extent as the conventional 2-legged exercise test.

LIMITATIONS: The results can be generalized only to people who are able to ambulate with their prosthesis.

CONCLUSIONS: The graded 1-legged exercise test was feasible and provided a valid assessment of peak aerobic capacity and exercise tolerance in older people walking with a lower-limb prosthesis.