After an ankle injury, residual symptoms can followed to recurrent sprain in

physical activity and 30% of its lead to functional ankle instability (FAI)

Therefore, the aim of this study was to examine the isokinetic concentric and

eccentric torque measures of the ankle musculature to body weight in female

athletes with and without FAI.30 female athletes, who play in pro league of

Tehran, participated in this descriptive study. Participants were assessed using

questionnaire and clinical tests. Isokinetic measurement speed for inversion and

eversion was 60 and plantar flexion and dorsi flexion was 120 degree/

second.Data were analyzed by independent T- test.The results indicated a

significant difference in peak torque of concentric plantar flexor to body weight

in FAI and healthy groups (P<0.05).Therefore, concentric plantar flexion may be

an important contributing factor to FAI; this finding could also lead to more

effective protocols in the treatment and rehabilitation of FAI