Submaximal exercise in persons with stroke: Test-retest reliability and concurrent validity with maximal oxygen consumption

Eng JJ, Dawson AS, Chu KS. Submaximal exercise in persons with stroke: test-retest reliability and concurrent validity with maximal oxygen consumption. Arch Phys Med Rehabil 2004;85:113-8. Objective: To establish the test-retest reliability and concurrent validity with maximum oxygen consumption ((V) over dotO(2)max.) for 3 submaximal exercise tests in persons with chronic stroke: (1) submaximal treadmill test, (2) submaximal cycle ergometer test, and (3) 6-minute walk test (6MWT). Design: Prospective study using a convenience sample. Setting: Free-standing tertiary rehabilitation center. Participants: A volunteer sample of 12 community-dwelling individuals who had a stroke with moderate motor deficits. Interventions: Not applicable. Main Outcome Measures: Heart rate, blood pressure, and oxygen consumption ((V) over dotO(2)) were assessed during the exercise tests. Results: Test-retest reliability was good to excellent for the exercise tests (maximal and submaximal tests). (V) over dotO(2) for all submaximal measures related to (V) over dotO(2)max (r range, .66 - .80). Neither the 6MWT distance, self-selected gait speed, nor hemodynamic measures related to (V) over dotO(2)max. Conclusion: The (V) over dotO(2) measures of the submaximal exercise tests had excellent reliability and good concurrent validity with (V) over dotO(2)max. Submaximal exercise tests may be a method by which to monitor the effects of interventions after a screening test (eg, symptom-limited graded exercise test, dobutamine stress echocardiograph).