The effect of dual-task on postural control and gait in individuals with Down syndrome: a systematic review

Background and aims Individuals with Down syndrome (DS) exhibit deficits in postural control (PC) and gait. Dual-task (DT) paradigms, which involve performing concurrent cognitive or motor tasks, may exacerbate these deficits or, conversely, serve as effective interventions. Objective This systematic review synthesizes evidence on how DT conditions affect PC and gait in individuals with DS, examining both acute effects and long-term training outcomes. Methods PubMed, Web of Science, and Scopus were searched from inception to February 2025. Included studies examined DT effects on PC or gait in DS populations. Risk of bias was assessed using ROBINS-I (non-randomized studies; non-RCTs) and RoB-2 (randomized controlled trials; RCTs). Due to heterogeneity in the outcome measures, a narrative synthesis following SWiM guidelines was conducted. Results Ten studies [363 participants; mean age 13.66 ± 2.53 years; eight non-RCTs (including six with control groups) and two RCTs] met inclusion criteria. Eight studies examining acute DT effects demonstrated that concurrent cognitive or motor tasks significantly impaired gait parameters (reduced velocity, increased step time, prolonged double support phase) and increased postural sway in individuals with DS compared to single-task conditions. These deficits were observed across various DT paradigms, including counting, word generation, and object manipulation. Conversely, two long-term DT intervention studies (8 weeks) reported significant improvements in dynamic balance, functional independence, and DT performance. IQ scores, reported in six studies (mean range: 26.97–66.60), correlated positively with gait speed and step length. Risk of bias was moderate in seven studies, low in two, and raised some concerns in one. Conclusion Acute DT conditions compromise PC and gait in individuals with DS, reflecting attention resource limitations. However, preliminary evidence suggests that DT training may improve long-term functional outcomes. Longitudinal, high-quality RCTs with standardized protocols and comprehensive cognitive assessment are urgently needed to establish evidence-based DT interventions for this population and determine whether initial improvements are sustained over time. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD42023483849 , CRD42023483849.