Combined Effects of Aerobic Exercise and Cognitive Training on Cognition After Stroke

Exploring Potential Synergistic Effects of Aerobic Exercise and Cognitive Training on Cognition After Stroke.

The objective of the 'Exploring potential synergistic effects of aerobic exercise and cognitive training on cognition after stroke' pilot trial is to investigate the combined effects of aerobic and cognitive training on cognition after stroke. This is to lay the groundwork for a larger RCT on the same topic. Twenty patients greater than 6 months post-stroke will be randomly assigned into one of four following treatment groups: (i) aerobic training (AEROBIC group), (ii) cognitive training (COGNITIVE group), (iii) aerobic exercise plus cognitive training (AEROBIC+COGNITIVE group); and (iv) non-aerobic range of motion (ROM) and unstructured mental activity (CONTROL group) (for group descriptions, please see detailed description below). We hypothesize that the combination of aerobic exercise and cognitive training will be more effective in improving cognition after stroke than either treatment on its own.

Aerobic exercise: Body weight support (BWS) treadmill exercise at moderately high intensity (60-70% of heart rate reserve) using 15-30% BWS. An additional 6-10 min will be needed for warm-up and cool-down. Heart rate will be continuously monitored, and blood pressure and rating of perceived exertion (RPE) will be measured periodically. Cognitive training: Computerized dual n-back training program that involves a working memory task, the difficulty of which adapts to the individual participant's performance. ROM exercise: Non-aerobic passive and active movement of upper and lower extremity joints performed with the subject lying on a plinth. RPE will be recorded every 5 minutes to ensure intensity remains low. Mental activities: Unstructured mental activity: such as listening to light novels on tape, which will be selected by the subject from a pre-determined list.

6-week program of one 20-min session of aerobic training and one 20-min session of ROM exercise 5 days/week.

6-week program of one 20-min session of cognitive training and one 20-min session of ROM exercise 5 days/week.

6-week program of one 20-min session of aerobic training and one 20-min session of cognitive training 5 days/week.

6-week program of one 20-min session of ROM exercise and one 20-min session of unstructured mental activity 5 days/week.

One 20-min session of body weight support treadmill training at moderate to high intensity (60-70% heart rate reserve) 5 days/week for 6-weeks.

One 20-min session of cognitive training (computerized dual n-back training program) 5 days/week for 6 weeks.

One 20-min session of range of motion exercise (non-aerobic passive and active movement of upper and lower extremity) 5 days/week for 6-weeks.

One 20-min session of unstructured mental activity (e.g., listening to light novels on tape) 5 days/week for 6-weeks.

Flanker Test is a computerized test of selective attention and reaction time that involves a motor response. The participant needs to focus and identify an item presented on a screen while ignoring task-irrelevant distractors. Performance on this test has been shown to improve with exercise.

A measure of visual working memory wherein the subject is shown a set of n digits for study. After a short delay, a digit is shown and the subject is asked to recall whether that item was in the previously viewed set

A measure of self-reported deficits in completing simple everyday tasks due to failures in attention, memory, perception, and motor function.

Inclusion Criteria: ≥18 years of age Diagnosis of ischemic or hemorrhagic stroke >6months ago Be able to perform a two-step command Be able to walk ≥10m with/without aid Live within a 75km radius of the QE II Pass a cardiology screen for safe participants in exercise training Exclusion Criteria: Have moderate or severe receptive aphasia Have terminal illness, life-threatening co-morbidity or concomitant neurological or psychiatric illness