Experimental Study On The Effect Of Neuromuscular Training On Lower Limb Stiffness In Young Recreational Athletes

INTRODUCTION:The stiffness of the lower limbs is potentially related to athletic performance,and the magnitude of the stiffness can determine the amount of external force required to produce an injury.At present,studies have shown that plyometric training or strength training can enhance the stiffness of the lower limbs,and it is predicted that the combination of the two can make the neuromuscular control ideally improved.Moreover,some studies have shown that exercise intervention can increase vertical stiffness,but the impact of specific local tissues is not clear.Therefore,the purpose of this study is to explore the effects of neuromuscular training combined with plyometric training and strength training on young recreational athletes'lower limb muscle stiffness,Achilles tendon stiffness,and vertical stiffness,and the changes in lower limb stiffness caused by training on athletic performance Impact.This hopes to provide new ideas for improving athletes'performance,reducing the occurrence of sports injuries and preventing sports injuries.METHODS:In this study,38 young recreational athletes engaged in regular(at least three times a week)sports(such as football,volleyball,basketball,etc.)were randomly divided into 19 experimental groups and 19 control groups by SPSS.Subjects in the experimental group still maintain their original exercise habits and perform neuromuscular training three times a week;subjects in the control group continue to maintain their original exercise habits without any special strength training or u plyometric training.Before and after the six-week training intervention,MYOTON was used to measure muscle stiffness and Achilles tendon stiffness;Kistler portable force plates were used to measure vertical stiffness(hopping),vertical stiffness(drop jump),and jump height related to athletic performance,Peak response force index and vertical ground reaction force.Repeated measurement two-way analysis of variance was used to compare muscle stiffness,Achilles tendon stiffness,vertical stiffness,jump height,peak vertical ground reaction force,and reaction force index in each group(time×group)before and after intervention.Ancova was used to analyze lower limb Effect of stiffness on athletic performance.RESULTS:The results of repeated measurement analysis of variance showed that:(1)compared with the control group,the stiffness of the right medial gastrocnemius muscle(F=7.23,P=0.011,?~2_p=0.167)in the experimental group was significantly increased after intervention,Compared with the control group,the stiffness of the right Achilles tendon(F=5.098,P=0.03,?~2_p=0.124)in the experimental group was significantly increased after the intervention.(3)Compared with the control group,after the intervention,the vertical stiffness of the left lower extremity(hopping)(F=5.655,P=0.023,?_p~2=0.136)in the experimental group was significantly increased,And the difference in vertical stiffness(hopping)on both sides of the experimental group changed from the original 37.4 N/m/kg to the current 12.82 N/m/kg;compared with the control group,After the intervention,the vertical stiffness(drop jump)of the lower limbs(F=7.394,P=0.01,?2p=0.17)in the experimental group was significantly increased.(4)Compared with the control group,after the intervention,the reaction force index(F=11.502,P=0.02,?_p~2=0.242)in the experimental group was significantly increased.According to the analysis of covariance,the stiffness of he right medial gastrocnemius muscle(F=0.96,P=0.795,?~2_p=0.003),the stiffness of the right Achilles tendon(F=0.923,P=0.344,?~2_p=0.028),and the vertical stiffness of the left lower limb(hopping)(F=0.616,P=0.438,?~2_p=0.019)has an effect on the reaction force index;compared with the control group,the experimental group's jump height after intervention(F=16.894,P<0.001,?~2_p=0.319)to get a very significant increase.According to the analysis of covariance,the stiffness of he right medial gastrocnemius muscle(F=0.032,P=0.859,?~2_p=0.001),the vertical stiffness of the left lower limb(hopping)(F=1.582,P=0.218,?~2_p=0.047),and The lower limb vertical stiffness(drop jump)(F=3.064,P=0.09,?~2_p=0.087)has an effect on the jumping height;the vertical ground reaction force peak has no significant difference in the interaction effect of time×groups(F=0.000,P=0.984,?~2_p<0.001).CONCLUSION:Six weeks of neuromuscular training is a training method for young recreational athletes that can effectively improve the stiffness characteristics of the lower limbs,and the improvement of the stiffness of the lower limbs can help improve the athletic performance of the young recreational athletes.Six-week training intervention can improve the symmetry of vertical stiffness,and the vertical stiffness of the lower limbs can be improved without significant changes in the vertical ground reaction force peak,suggesting that six-week training intervention may prevent and reduce the risk of injury.