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

Overview

The majority of people after stroke demonstrate mobility limitations, which may reduce their physical activity levels. Task-specific training has shown to be an effective intervention to improve mobility in individuals with stroke, however, little is known about the impact of this intervention on levels of physical activity. The main objective will be to investigate the efficacy of a task-specific training, focused on both upper and lower limbs, in improving physical activity levels and mobility in individuals with stroke. The secondary objective will be to investigate the effect of the training, in improving muscle strength, exercise capacity, and quality of life. A randomized controlled trial with blinded assessment will assign eligible participants to either: 1) experimental group or 2) control group. Participants will receive interventions three times per week over 12 weeks. The experimental group will undertake task-specific training, while the control group will undertake global stretching and memory exercises, and health education sessions. Primary outcomes will include measures of physical activity levels and mobility, whereas secondary outcomes will be muscle strength, exercise capacity, and quality of life. The outcomes will be measured at baseline, 12 weeks post-intervention, and four and 12 weeks follow-up. The findings of this trial have the potential to provide important insights regarding the effects of task-specific training, focused on both upper and lower limbs, in preventing secondary post-stroke complications and improving the participants' general health through changes in physical activity levels.

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.