Article

Mechanical efficiency can assess motor performance in individuals with
physical disabilities. The purpose was to determine the utility of predicting it
from heart rate (HR) during a self-paced stair-climbing test in adults with
chronic hemiparesis after stroke and to determine the minimal detectable change
of net mechanical efficiency (MEnet) measured by this exercise. METHODS: First,
15 subjects with chronic hemiparesis participated in a validation study (A) and
then 28 took part in a repeatability study (B). In study A the MEnet was
calculated from external work and oxygen uptake above rest (dVO2), as directly
measured and as predicted from body weight and increase in heart rate (dHR). In
study B, predicted dVO2 was used to obtain MEnet for duplicate stair-climbing
tests (T1, T2) with >30 min rest between. RESULTS: Measured MEnet was closely
related to predicted MEnet (r = 0.97, p < 0.001). In study B predicted MEnet for
T2 and T1 were closely related (r = 0.91, ICC = 0.90). CONCLUSION: With a minimal
detectable change of 0.6% (0.053 of average MEnet score of 10.4%), MEnet values
from the stair-climbing test seem sufficiently meaningful to estimate ambulatory
ability and its changes with interventions or walking aids in adults with
hemiparesis. IMPLICATIONS FOR REHABILITATION: Ambulatory ability can be estimated
from mechanical efficiency, obtained from a 5-min stair-climbing test utilizing a
4-step stair, to measure external work, and the change in heart rate above rest
to estimate the metabolic cost of the task. A change of > 0.6% in mechanical
efficiency by this stair-climbing test indicates a significant change in
ambulatory ability of persons with hemiparesis.

Langue : ANGLAIS