The purpose of this study was to identify the effects of isokinetic exercise programs on the muscular function recovery of athletes with chronic ankle sprain. The subjects were 12 male college athletes with chronic ankle sprain assessed by maximum inv...
The purpose of this study was to identify the effects of isokinetic exercise programs on the muscular function recovery of athletes with chronic ankle sprain. The subjects were 12 male college athletes with chronic ankle sprain assessed by maximum inversion stress roentgnography. 12 participants were randomly assigned into two different treatment groups: concentric isokinetic exercise(CIE, n=6) and eccentric isokinetic exercise(EIE, n=6).
The CIE group performed concentric contractions of each ankle dorsiflexor and plantarflexor muscles and the EIE group performed eccentric contractions of each ankle muscle group three days for eight weeks. The instrument was used a spectrum of angular velocities ranging from 30°/sec to 150°/sec with 30°/sec intervals and EMG to record activity of tibialis anterior, soleus, and gastrocnemius, for involved side.
The results of this study were following as:
1. Muscular function
1) Dorsiflexors
CIE group showed increases (p<.05) in peak torque and peak torque % body weight and EIE group showed marked increases(p<.01) in peak torque % body weight, average power, and total work in the involved side. However, both training groups did not display these marked changes in the uninvolved side after the 8-week period.
2) Plantarflexors
EIE group showed marked increases(p<.01) in peak torque and peak torque % body weight but CIE group didn't increase in the involved side. In addition, both training groups did not display these marked changes in uninvolved side after the 8-week period.
3) DF/PF ratio, Average ROM, and IV/UV ratio.
CIE group showed marked decreases (p<.01) in the IV/UV ratio of dorsiflexion. However, EIE group did not display these marked changes after the 8-week period.
2. EMG
EIE group showed marked increases (p<.01) in the gastrocnemius. However, both training groups did not display marked changes in other sides after the 8-week period.
These results also indicated that eccentric isokinetic exercise has a greater influence on muscular function, especially plantarflexor an descending, than concentric isokinetic exercise, however, the improvements in the IV/UV ratio of dorsiflexion were better in the CIE group compared with EIE group after the training.
The findings of these results implied that with isokinetic exercise programs used in this study, it is possible to recover muscular function in athletes with chronic ankle sprain. It was also indicated that extensive training involving a high number of repetitions and eccentric contractions was safe, effective, and well tolerated for the athletes with chronic ankle sprain.