Abstract-As the injury and re-injury to lateral ankle ligaments are common in athletes due to the restricted ankle dorsiflexion range of motion (DROM) and dynamic balance (DB), this study was aimed to find out the effectiveness of MobEx intervention to improve and sustain the DROM and DB. Twenty-seven athletes with history of unilateral LAS were recruited in one of the experimental, placebo and control groups randomly. All of them were assessed for their DROM and DB using weight bearing lunge test and Modified Bass Test for Dynamic Balance respectively as a pre-test score. After this pre-test measurement, the experimental group were intervened by MobEx intervention for six weeks and the placebo group were intervened by placebo intervention for six weeks too. Whereas the control group neither intervened by MobEx intervention nor the placebo Intervention. The DROM and DB were measured after sixweeks for post-test scores and again after one month for retention-test scores. The primary aim was examined with repeated measures of multivariate analysis of variance. The interaction for the repeated measures of multivariate analysis of variance was statistically significant for the DROM and DB in the experimental group (P<0.001), and for the DB in the placebo group (P<0.001). The improvements in DROM and DB were significantly greater at both six weeks and one month in favor of experimental group. The result suggests that the MobEx intervention is effective not only in improving the DROM and DB but also to retain its improved effects.