Efficacy of Task-specific Training on Physical Activity Levels Post-stroke

The sample size was calculated to detect a between-group difference of 0.15 m/s in gait speed, with 80% power, at a two-tailed significance level of 0.05. In an RCT with a similar population and intervention (Yang et al. 2006) gait speed for the control and experimental groups at baseline was 0.78±0.14 m/s and 0.84±0.13 m/s and after were 0.78±0.15 m/s (p=0.8) and 0.93±0.14 m/s (p<.001), respectively. Based on these values, 15 participants per group will be required (a total of 30 participants). Assuming a dropout rate of 15%,66 a total of 36 participants will be recruited (18 per group).

Data analyses will be performed by the SPSS for Windows® (release 17.0, SPSS Inc., Chicago, IL, USA). Descriptive statistics will be carried-out for all outcome variables. Differences between the groups at baseline will be investigated with the independent Student's t-tests for all variables related to the demographic and clinical characteristics. If differences between the groups at baseline exist, analysis of covariance will be used to eliminate the influence of extraneous factors.

The effects of the interventions will be analysed in two ways, namely from the data collected and by intention-to-treat analyses, where the last available value in the dropouts will be carried forward to represent the missing data. Analyses of variance with repeated measures (2×4) will be employed to investigate the mean and interaction effects between the groups (intervention×control) and the time (preintervention, postintervention, and follow-up) for the primary and secondary outcomes. Group descriptions will be presented as mean (SD) and effect sizes with 95% confidence intervals (CIs) will be reported.

The effect sizes will be calculated to determine the magnitude of the differences between the groups. The differences between the two mean values will be expressed in units of their SD, expressed as Cohen's d, or mean results for the experimental group minus the mean results for the control group, divided by the SD of the control group. Effect sizes between 0.2 and 0.5 will be considered small; between 0.5 and 0.8, medium; and above 0.8, large.

Inclusion criteria

• have a clinical diagnosis of first or recurrent stroke more than six months since the onset of their strokes;
• are older than 19 years of age;
• are able to independently walk 10 m with or without walking aid devices;
• have tone of elbow flexor muscles below 4 on modified Ashworth scale;
• are inactive or insufficient, based on Centers for Disease Control and Prevention criteria;
• get medical permission for physical activity practice

Exclusion criteria

• have severe cognitive deficits, as assessed by the mini-mental state exam and/or language problems (comprehensive afasia), as evaluated by simple motor commands ("lift your nonparetic upper limb and open your hand"), which might prevent them from following instructions during the data collection and/or the interventions;
• have history of severe heart disease and/or uncontrolled blood pressure;
• have pain and/or other adverse health conditions which might affect the performance in the intervention program, such as vestibular disturbances, severe arthritis, or other neurological disorders.