Tang A, Sibley KM, Thomas SG, McIlroy WE, Brooks D. Maximal exercise test results in subacute stroke.
Objectives
To establish the feasibility and reliability of graded maximal exercise testing, suitability of standard indexes of maximum oxygen consumption (V̇o2max), and evidence of trial-to-trial practice effects in subacute stroke.
Design
Descriptive, cross-sectional study.
Setting
Rehabilitation hospital.
Participants
Consecutive sample of 35 participants (mean age, 65.7±2.6y; mean days poststroke, 17.6±2.2d).
Interventions
Not applicable.
Main Outcome Measures
Graded maximal exercise test using semirecumbent cycle ergometry. A subset (n=20) performed repeated tests to determine test-retest reliability and presence of practice effects.
Results
Thirty-one (89%) participants completed the exercise test without symptomatic responses (mean peak level of oxygen consumed [Vo2peak], 10.7mL·kg−1·min−1; peak work rate, 39W). Twelve (34%), 15 (44%), and 3 (9%) participants achieved oxygen consumption per unit time (V̇o2) plateau, respiratory exchange ratio, and heart rate criteria, respectively. Although test-retest correlations were high (intraclass correlation coefficient range, .67–.87), higher Vo2peak (1.0mL·kg−1·min−1, P=.04) and work rate (7.3W, P=.01) were observed with repeated testing, with no associated increase in reaching standard criteria for V̇o2max.
Conclusions
This work has important implications for developing guidelines for measuring aerobic capacity early after stroke. Although maximal exercise testing using semirecumbent cycle ergometry is feasible, standard V̇o2max criteria are not consistently appropriate. At least 1 practice trial is recommended before the actual evaluation is performed.
aDepartment of Physical Therapy, University of Toronto, Toronto, ON, Canada
bInstitute of Medical Science, University of Toronto, Toronto, ON, Canada
cFaculty of Physical Education and Health, University of Toronto, Toronto, ON, Canada
dToronto Rehabilitation Institute, Toronto, ON, Canada.
Reprint requests to Dina Brooks, PhD, Dept of Physical Therapy, Faculty of Medicine, University of Toronto, Rm 160, 500 University Ave, Toronto, ON M5G 1V7, Canada
Supported by the Canadian Institutes of Health Research (Canada Research Chair, New Investigator Award), the Government of Ontario/Heart and Stroke Foundation of Ontario, the Toronto Rehabilitation Institute and the Physiotherapy Foundation of Canada, the Natural Sciences and Engineering Research Council of Canada, and the Provincial Rehabilitation Research Program, Ontario Ministry of Health and Long Term Care.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.
ABSTRACT