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KSR Number: KSRA62298

Progressive resistance training increases strength after stroke but this may not carry over to activity: a systematic review

Risk of Bias Assessment

Overall summary: High risk of bias in the review

Bottom Line

Current evidence suggests that progressive resistance training can generally increase immediate muscle strength but may not impact immediate activity levels compared to no intervention or placebo in patients who have had a stroke. Of note, these findings should be interpreted with caution, since methodological weaknesses mean that reviewer error and bias cannot be ruled out, and heterogeneity and the robustness of the data were not adequately explored. Future studies are needed to provide additional evidence for patients early after stroke and for those who need to engage in upper limb strengthening following stroke.

Risk of Bias Assessment

Overall summary High risk of bias in the review

High

No information was provided on the number of authors involved in the risk of bias assessment, meaning reviewer error and bias cannot be ruled out. Heterogeneity was assessed and found to be moderate for some outcomes; the source of this heterogeneity was not explored further. Publication bias was not assessed; however, this was considered appropriate due to the small number of included studies. Robustness of the findings was not assessed.

A. Did the interpretation of findings address all of the concerns identified in Domains 1 to 4? Probably no
B. Was the relevance of identified studies to the review's research question appropriately considered? Probably yes
C. Did the reviewers avoid emphasizing results on the basis of their statistical significance? Probably yes
Risk of bias in the review High

Details of Review

Number of studies 11
Number of participants 314
Last search date May 2017
Review type Intervention
Objective To evaluate the effect of progressive resistance training on strength after stroke; and to determine whether any increases in strength are carried over into activity.
Population Adults (aged > 18 years old) of either gender who were diagnosed with stroke and had muscie strength sufficient for progressive resistance training
Interventions Progressive resistance training (defined as exercising against an external load that corresponds to 8 to 12 repetitions maximum, at least twice per week, with resistance increased as strength increases).
Comparator No intervention or placebo.
Outcome Primary outcome: muscle strength (measured as maximum force/torque and congruent with the muscles trained, measured immediately after the intervention) of the affected arm or leg.

Secondary outcome: activity (measured by direct observation of performance (e.g. 10-m walk test, block test)).
Study design Randomised or quasi-randomised trials.

Results

In terms of muscle strength, pooled analysis reported an increase in immediate muscle strength following progressive resistance training compared with no intervention or placebo in patients with stroke (standardised mean difference [SMD] 0.98, 95% confidence interval [CI] 0.67 to 1.29; 6 studies, n=163 patients). Pooled analysis also reported no difference in immediate muscle strength for patients late after stroke following progressive resistance training compared with no intervention or placebo (SMD 1.08, 95% CI 0.74 to 1.42; 5 studies). Subgroup analysis based on upper or lower limbs reported no difference in immediate muscle strength for progressive resistance training in the lower limb compared with no intervention or placebo in patients with stroke (SMD 1.08, 95% CI 0.74 to 1.42; 5 studies).

In terms of activity, pooled analysis reported no difference in immediate activity following progressive resistance training compared with no intervention or placebo in patients with stroke (SMD 0.42, 95% CI -0.08 to 0.91; 6 studies, n=163 patients). Pooled analysis also reported no difference in immediate activity for patients late after stroke following progressive resistance training compared with no intervention or placebo (SMD 0.40, 95% CI -0.17 to 0.97; 5 studies). Subgroup analysis based on upper or lower limbs reported no difference in immediate activity for progressive resistance training in the lower limb compared with no intervention or placebo in patients with stroke (SMD 0.40, 95% CI -0.17 to 0.97; 5 studies).

Full Risk of Bias Assessment

The study objectives and eligibility criteria were well described and appeared appropriate for the review question. No restrictions were reported based on study characteristics or sources of information.

1.1 Did the review adhere to pre-defined objectives and eligibility criteria? Probably yes
1.2 Were the eligibility criteria appropriate for the review question? Probably yes
1.3 Were eligibility criteria unambiguous? Probably yes
1.4 Were all restrictions in eligibility criteria based on study characteristics appropriate (e.g. date, sample size, study quality, outcomes measured)? Probably yes
1.5 Were any restrictions in eligibility criteria based on sources of information appropriate (e.g. publication status or format, language, availability of data)? Probably yes
Concerns regarding specification of study eligibility criteria Low

EMBASE, CENTRAL, and the Physiotherapy Evidence Database (PEDro) databases were searched for relevant studies. The reference lists of included studies were handsearched to identify additional records. Searches were not restricted by date, publication format or language. The search strategy was reported and appears comprehensive. Two reviewers were independently involved in the study selection process and any disagreements were discussed until consensus was reached.

2.1 Did the search include an appropriate range of databases/electronic sources for published and unpublished reports? Probably yes
2.2 Were methods additional to database searching used to identify relevant reports? Probably yes
2.3 Were the terms and structure of the search strategy likely to retrieve as many eligible studies as possible? Yes
2.4 Were restrictions based on date, publication format, or language appropriate? Probably yes
2.5 Were efforts made to minimise error in selection of studies? Yes
Concerns regarding methods used to identify and/or select studies Low

Two reviewers were independently involved in the data extraction process, and extracted data was checked by a third reviewer. Sufficient study information was provided to enable interpretation of the results. The methodological quality of the included studies was assessed using the PEDro scale. No information was provided on the number of authors involved in the risk of bias assessment.

3.1 Were efforts made to minimise error in data collection? Yes
3.2 Were sufficient study characteristics considered for both review authors and readers to be able to interpret the results? Probably yes
3.3 Were all relevant study results collected for use in the synthesis? Probably yes
3.4 Was risk of bias (or methodological quality) formally assessed using appropriate criteria? Probably yes
3.5 Were efforts made to minimise error in risk of bias assessment? No information
Concerns regarding methods used to collect data and appraise studies Unclear

All relevant studies appear to have been included in the synthesis. The methods were explained and appeared to be appropriate. All pre-defined analyses were reported. There was substantial clinical heterogeneity given that studies used different outcome measures for both strength and activity; however, statistical heterogeneity was assessed and found to be low or moderate for the outcomes reported. The source of this heterogeneity was not explored further. Publication bias was not assessed. Robustness of the findings was not assessed.

4.1 Did the synthesis include all studies that it should? Probably yes
4.2 Were all pre-defined analyses reported or departures explained? Probably yes
4.3 Was the synthesis appropriate given the degree of similarity in the research questions, study designs and outcomes across included studies? Probably yes
4.4 Was between-study variation minimal or addressed in the synthesis? No
4.5 Were the findings robust, e.g. as demonstrated through funnel plot or sensitivity analyses? Probably no
4.6 Were biases in primary studies minimal or addressed in the synthesis? Probably yes
Concerns regarding synthesis and findings High

Abstract

Question Does progressive resistance training improve strength and activity after stroke? Does any increase in strength carry over to activity? Design Systematic review of randomised trials with meta-analysis. Participants Adults who have had a stroke. Intervention Progressive resistance training compared with no intervention or placebo. Outcome measures The primary outcome was change in strength. This measurement had to be of maximum voluntary force production and performed in muscles congruent with the muscles trained in the intervention. The secondary outcome was change in activity. This measurement had to be a direct measure of performance that produced continuous or ordinal data, or with scales that produced ordinal data. Results Eleven studies involving 370 participants were included in this systematic review. The overall effect of progressive resistance training on strength was examined by pooling change scores from six studies with a mean PEDro score of 5.8, representing medium quality. The effect size of progressive resistance training on strength was 0.98 (95% CI 0.67 to 1.29, I 2 = 0%). The overall effect of progressive resistance training on activity was examined by pooling change scores from the same six studies. The effect size of progressive resistance training on activity was 0.42 (95% CI –0.08 to 0.91, I 2 = 54%). Conclusion After stroke, progressive resistance training has a large effect on strength compared with no intervention or placebo. There is uncertainty about whether these large increases in strength carry over to improvements in activity. Review registration PROSPERO CRD42015025401. [Dorsch S, Ada L, Alloggia D (2018) Progressive resistance training increases strength after stroke but this may not carry over to activity: a systematic review. Journal of Physiotherapy 64: 84–90]