Exercise-based interventions for physically active individuals with functional ankle instability: a systematic review of the literature

Ankle instability is highly prevalent in physically active individuals and the effectiveness of rehabilitation programs based on exercise is still unclear. The objective of this study is to assess the effects of any type of exercise programs compared to any other intervention or no intervention for physically active individuals with functional ankle instability (FAI) and to explore whether the effects vary according to the characteristics of the exercise program and outcome variables.We searched English, French and Portuguese language publications from the following databases: PubMed (National Library of Medicine, Bethesda, MD), SPORTDiscus, Physiotherapy Evidence Database, Academic Search Complete, Science Direct and Scielo. Combinations of the following key words were used: functional, instability, ankle, sports, exercise, proprioception, coordination. Eligible studies were randomized control trials (RCT) or clinical control trials (CCT) that compared an intervention consisting of an exercise program in adult participants with functional ankle instability (FAI) and defined as physically active against other exercise programs, other interventions or no intervention. Two independent reviewers applied the selection criteria and assessed the quality of the studies.A total of 567 studies were retrieved from the literature search and eight articles met the inclusion criteria. Included studies assessed dynamic and static postural control, proprioception, strength, self-reported instability, range of motion, balance, pain and muscle reaction time. All studies compared an exercise program versus no intervention, one compared exercise against the same program with the addition of stochastic resonance, and two studies compared different exercise programs.Exercise programs focused on coordination, balance and proprioception appear to improve functional performance for physically active individuals with functional instability and reduce subjective instability. Exercise training presents as an option to improve postural control, joint position sense or recurrent injury rates. Further study is suggested in order to determine optimal exercise programs for specific sports populations.