Does Strength Training for Chronic Ankle Instability Improve Balance and Patient-Reported Outcomes and by Clinically Detectable Amounts? A Systematic Review and Meta-Analysis.

OBJECTIVE Strength training as a form of exercise therapy has long been used to maintain or promote strength, but its effectiveness as a treatment intervention in chronic ankle instability is not fully understood. The purpose of this study was to evaluate the effects of strength training compared to no exercise and neuromuscular control training on balance and self-reported function in people with chronic ankle instability (CAI). METHODS Eight databases (PubMed, Embase, Cochrane Library, Web of Science, EBSCO, PEDro, CNKI, and WanFang) were searched in June 2020. Randomized controlled trials involving strength training conducted on individuals with CAI were included. Data were extracted by 2 independent reviewers using a standardized form. Methodological quality and risk of bias were assessed by using the PEDro scale. In addition, the evaluation system (Grading of Recommendations Assessment, Development and Evaluation [GRADE]) was used to determine the strength of evidence. A total of 554 studies were initially screened, resulting in a final selection of 11 RCTs involving 428 participants, and 8 RCTs were included in the final meta-analysis. Compared with no exercise, strength training demonstrated some benefits in the Star Excursion Balance Test (SEBT) (anterior: weighted mean difference [WMD] = 2.39, 95% CI = 0.60-4.18; posteromedial: WMD = 3.30, 95% CI = 0.24-6.35; posterolateral: WMD = 2.97, 95% CI = 0.37-5.57), but these intervention results did not reach the minimal detectable change values. CONCLUSIONS Available evidence showed that, compared with controls, strength training did not produce any minimal detectable changes on SEBT or Foot and Ankle Ability Measure scores in individuals with CAI. Clinicians should use strength training cautiously for improving balance and symptoms in CAI.