Effects of hydrokinesitherapy on balance and walking ability for stroke survivors: update of a systematic review and meta-analysis of randomized controlled studies

BACKGROUND: Balance dysfunction often affects stroke patients. While our earlier research indicated that aquatic exercise therapy could help, the evidence was initially rated as very low. With new studies emerging, this research aims to update the evidence on the effectiveness of water-based exercise in improving balance for stroke survivors. METHODS: The study followed PRISMA guidelines, retrieving records from five databases (Medline, Embase, CENTRAL, CINAHL, and SPORTDiscus) up to July 1, 2025. Two researchers independently conducted a two-step screening of titles, abstracts, and full texts to select studies. Quality was assessed using the ROB2 tool, and data extraction followed a set protocol. All steps were independently performed by two authors, with a third resolving any disagreements. Data extraction followed a set protocol, with two authors independently handling literature screening, bias assessment, and data extraction. Discrepancies were resolved by consulting a third party. Data analysis was conducted using RevMan 5.4 and Stata, calculating combined effect sizes using either SMD or MD based on the Q test results, and choosing between random- or fixed-effects models. Sensitivity analysis was done with Stata 15.0, and publication bias was evaluated using funnel plots and Egger's test. Evidence quality was assessed with the GRADE system. RESULTS: A total of 29 RCTs involving 1075 stroke patients were included in this study. The results indicated that the water-based exercise can improve the balance function of stroke survivors based on BBS score with moderate effect size (N.=523, SMD=0.71, 95% CI: 0.28-1.14, P=0.001) and FRT(n=107, SMD=0.97, 95% CI: 0.32-1.61, P=0.003), while test time for TUGT in the intervention group was not improved (SMD=-0.46, 95% CI: -0.96 to 0.04, P=0.07). The quality of the evidence for BBS was assessed as moderate, and the quality of evidence for TUGT and MBI was assessed as very low. CONCLUSIONS: Moderate strength of evidence suggests that aquatic exercise therapy may improve the balance function of stroke patients. However, due to methodological limitations, inconsistent results, and clinical heterogeneity, this result should be interpreted with caution. Future research employing more rigorous study designs is necessary to substantiate these results.