Abstract: Objective To observe the effect of strengthening training of hip muscles on functional ankle instability (FAI).Methods From May, 2015 to June, 2016, 40 patients with FAI were randomly divided into control group (n=20) and observation group (n=20). Both groups were treated with routine exercise training including muscle strength and proprioceptive training of the ankle joint, while the treatment group received hip muscle strength training in addition, for six weeks. They were evaluated with hip force assessment, postural stability assessment, Star Excursion Balance Test (SEBT) and Cumberland Ankle Instability Tool (CAIT).Results There was no significant difference in all the indexes between two groups before treatment (P>0.05). After treatment, the peak torques of hip muscles increased in the observation group (t>3.528, P<0.01); the overall stability index, anteroposterior stability index, middle-lateral stability index decreased in both groups (t>2.360, P<0.05); the distance of eight direction in SEBT increased in both groups (t>2.254, P<0.05); the score of CAIT increased in both groups (t>3.268, P<0.01). All the above indexes were better in the observation group than in the control group (t>2.161, P<0.05).Conclusion Strengthening training of hip muscle, based on conventional ankle muscle strength and proprioceptive training, could facilitate to improve FAI.

Key words: hip muscle, strength training, ankle, functional ankle instability