Effects Of Blood Flow Restriction Training With Different Pressures On The Rehabilitation Effect Of Knee Injury Athletes

Objective: The purpose of this study is to implement different pressure blood flow restriction training for athletes with knee joint injuries,to study its therapeutic effect on athletes’ knee joint injuries,and to compare the rehabilitation effects of different pressure blood flow restriction training on athletes’ knee joint injuries.Methods: According to the inclusion and exclusion criteria,20 athletes aged 18-24 years old and diagnosed as knee joint injuries were included.The subjects were randomly divided into two groups,group A was pressurized by 300 mm Hg,and group B was pressurized by 200 mm Hg.Both were trained for 6 weeks of blood flow restriction,3 times/week,40 minutes each time.Before and after the training,the thigh circumference,isokinetic muscle strength of knee flexor and extensor,active position sense of knee joint,balance function,motor function and knee joint subjective function score were evaluated.The data were analyzed by IBM SPSS(version 25.0).ShapiroWilk test is used to analyze the normality of measurement data.Paired-sample t-test and Wilcoxon signed-rank test were used to analyze changes before and after training.Two independent-sample t-tests and Mann-Whitney U test were used to compare differences between groups.Counting data comparison,using Fisher exact probability method.P<0.05 was considered statistically significant.Results: 1.Thigh circumference:Intra group comparison:compared with before training,thigh circumference(5cm,10 cm,15cm above patella)increased significantly in the two groups after training,and the difference was statistically significant(P<0.01).Comparison between groups: there was no significant difference in thigh circumference(5cm,10 cm,15cm above patella)before training(P>0.05);After training,the thigh circumference(suprapatellar 5cm,10 cm,15cm)in group A was higher than that in group B,and the difference was statistically significant.(P<0.05).2.Knee joint active position sense: Intra group comparison: compared with before training,the 45° active position sense error of knee joint in group A and the knee joint60° active position sense error in group B was decreased decreased after training,and the difference was statistically significant(P <0.01).The 60° active position sense error of knee joint after training in group A and 45° active position sense error of knee joint after training in group B compared with that before training,the difference was not statistically significant(P>0.05).Comparison between groups: The active position sense error of knee joint(45°,60°)before and after training was compared between the two groups,the difference was not statistically significant(P>0.05);3.Knee joint flexor and extensor isokinetic muscle strength: Intra group comparison: after training,the peak moment,relative peak moment,average power and moment at 0.2 seconds of knee flexor and extensor muscles of the two groups were increased compared with that before training,with statistical significance(P<0.01).Comparison between groups: peak moment,relative peak moment,average power and0.2 seconds moment of knee flexor and extensor muscles before and after training was compared between the two groups,and the difference was not statistically significant(P>0.05);4.Balance function: Intra-group comparison: after training,the reach distance of all directions of Y balance test in the two groups increased compared with those before training,and the difference was statistically significant(P< 0.01).Comparison between groups: the reach distance of all directions of Y balance test before and after training was compared between the two groups,the difference was not statistically significant(P>0.05);5.Motor function: Intra-group comparison: compared with before training,the performance of motor function test(Shuttle run test,Carioca test and Co-contraction test)in the two groups was improved after training,and the difference was statistically significant(group A:P<0.05;group B:P<0.01);Comparison between groups: the performance of motor function test(Shuttle run test,Carioca test and Co-contraction test)before and after training was compared between the two groups,the difference was not statistically significant(P>0.05);6.Knee subjective function score: Intra-group comparison: compared with before training,the IKDC scores of the two groups improved after training,the difference was statistically significant,and the difference was statistically significant(P<0.01).Comparison between groups: IKDC scores before and after training were compared between the two groups,the difference was not statistically significant(P>0.05).Conclusion:1.Both 300 mm Hg and 200 mm Hg of blood flow restriction training can effectively increase the thigh circumference of knee injury athletes,and the effect of 300 mm Hg of blood flow restriction training was more significant;2.Both 300 mm Hg and 200 mm Hg pressure blood flow restriction training can improve the knee joint active position sense of athletes with knee joint injury,and the effect of 300 mm Hg pressure blood flow restriction training is more significant;3.Both 300 mm Hg and 200 mm Hg pressure blood flow restriction training can effectively enhance the knee joint flexor and extensor muscle strength and explosive power of athletes with knee joint injuries,improve balance function,motor function and subjective knee function scores;blood flow restriction training has positive effect on knee joint injury rehabilitation of athletes.