The Influence Of Isokinetic Eccentric Training On Superior And Inferior Ankle Joints

[Method]There are altogether 30 objects of experiment,among them 10 objects are in control group,10 in superior ankle joint experimental group and 10 in inferior ankle joint experimental group.The eccentric training is taken in the same angular velocity-60°/s.The experiment goes on for 8 weeks.In the first week,the PT and TW of ankle joint muscle of the objects are measured before the experiment.At first the experimental is set in the model of concentric contraction and then the experimenter asks the objects get familiar with isokinetic eccentric training by telling them.Some special things they should pay attention to. Before the formal experiment,the objects are asked to do the warming-up exercises for 10 minutes,and then take eccentric training of 60°/s for 5 turns.All the objects are required to try their best to persist until the end of the experiment.Before the experiment the objects are asked to be well-prepared and try their best to finish the training according to the training plan.The objects are trained from the second to seventh weeks, three days a week.The objects in superior ankle joint experimental group are trained at 3 o'clock every Monday,Wednesday and Friday and the objects in inferior ankle joint experimental group are trained at 3 o'clock every Tuesday,Thursday and Saturday,then both groups are allowed to rest for 2 days.From the 2^nd to the 5^th week of the training the resisting moment of the eccentric training is 150%of the TW.Every set of training has 2 rounds(2 turns each round,15 times each turn and 15 seconds for a break).The next round of training does not start until the end of the first round of training.In the 6^th and 7^th week the frequency of the training is increased to 20 times each turn.The TW of the objects is increased to 180%.8 weeks after the training the PT and TW of ankle joint muscle of the objects are recorded.[Result]After 60°/s eccentric training,both the superior ankle joint muscle groups and the inferior ankle joint muscle groups are improved greatly on the sides of PT and TW.It shows that eccentric training is very effective whereas the control group has little change because the objects in this group don't accepted eccentric training.The ratio of the power of flexor and extensor on both superior side and inferior side has decreased in different degrees.After the training,the objects in experimental group can jump much higher especially their inferior side are improved greatly.[Conclusion](1) The 6 week's eccentric training has a very effective effect on strengthening the subjects' flexor and extensor on their ankle joints.The flexor and extensor of the subjects in the experimental group on the ankle joints of both superior side and inferior side are strengthened dramatically on PT and TW.It shows the eccentric training is really a very effective training method.(2) PT and TW are quite different because of different eccentric angular velocity.For the experimental group and the control group,PT and TW of flexor and extensor on superior side and inferior side tend to be:60°/s＞120°/s＞180°/s.It is proved that the greatest strength can be reflected in slow eccentric training.(3)After 6 week's eccentric training,the subjects in both groups can jump much higher in different degrees.It shows 60°/s eccentric train is very effective in improving the ability of jumping upward.(4) After 6 week's eccentric training,the ratio of the power of flexor and extensor on both superior and inferior side has decreased.It shows after the eccentric training the extensor of ankle joints become more powerful and difference between the flexor and extensor is narrowed which helps keeping the balance of flexor and extensor and prevents the muscle on the inferior side from being damaged.