Research On The Influence Of Different Static Squatting Modes Against The Wall On The Surface EMG Signal Of Vastus Medialis Obliquus Muscle

Introduction:In this study,three groups of subjects were asked to perform static squatting exercises with different foot widths(1.0 shoulder width,1.5 shoulder width),different squatting angles(30°,45°,60°)and different foot positions(neutral,internal rotation,external rotation).To analyze the influence of different modes on VMO/VL EMG ratio,provide static squatting mode to activate the vastus medialis muscle for different needs,and provide scientific basis for improving the training method of quadriceps muscle coordination and power generation.Methods:Sixty male college students in Capital University of Physical Education were selected,including 20 non-physical education students,20 badminton and football students,and the rest 20 basketball students.They volunteered to participate in the experiment and were in good physical and psychological condition without serious injury of quadriceps and knee joints.All subjects completed different combinations of foot widths(1.0 shoulder width,1.5 shoulder width),squatting angles(30°,45°,60°)and foot positions(neutral,internal rotation,external rotation)in random order.Each subject was required to complete a total of 18 test conditions.Each test condition was successfully tested three times,with an interval of 3 minutes between each condition.The original EMG of VL and VMO in 18 modes was collected and processed by surface EMG system,and the RATIO of VMO to VL was calculated.Finally,statistical comparison was conducted.Results:1.Results of VMO/VL EMG ratio in the normal group: i EMG factorial analysis showed that the main effect of bipedal width was statistically significant(P <0.05);After grouping i EMG values according to the width of two legs,one-way an OVA showed that there were differences in two groups(P<0.05),respectively 30°internal rotation(P=0.045)and 45° neutral(P=0.047).The results of factorial design analysis of RMS showed that there were statistically significant differences in the main effects of foot width and squatting Angle(P<0.05);After grouping the RMS values according to the width of the two legs,one-way an OVA showed that there was a difference in one group(P<0.05),is 30°internal rotation(P=0.046).When different squatting angles were used,there was a difference in one group(P < 0.05),is 1.0neutral(P=0.491).2.Results of VMO/VL EMG ratio in badminton and football groups: The results of i EMG factorial analysis showed that the main effect of bipedal width was statistically significant(P<0.05);Univariate an OVA after grouping i EMG bipod width showed that there were differences in three groups(P<0.05),respectively 30°neutral(P=0.032),30°external rotation(P=0.042),45°internal rotation(P=0.024).The results of factorial design analysis of RMS showed that there were statistically significant differences in the main effects of foot width and squatting Angle(P < 0.05);After grouping the RMS values according to the width of the legs,one-way an OVA showed that there were differences in three groups(P<0.05),respectively 30°internal rotation(P=0.031),30°external rotation(P=0.046)and 45°internal rotation(P=0.036),different results were found in one group with different squatting angles(P < 0.05),is 1.0external rotation(P=0.034).3.Results of VMO/VL EMG ratio in basketball group: The results of i EMG factorial analysis showed that the main effect of bipedal width was statistically significant(P<0.05);One-way an OVA of i EMG values grouped according to bipod width showed that there were differences in 2 groups(P < 0.05),respectively 30°internal rotation(P=0.045)and 45° neutral(P=0.038).The results of RMS analysis showed that the main effect of bipedal width was statistically significant(P <0.05);After grouping the RMS values according to the width of the legs,one-way an OVA showed that there were differences in two groups(P < 0.05),respectively30°internal rotation(P=0.043)and 45°neutral(P=0.036).4.Results of VMO/VL EMG ratio between groups: at 1.0 shoulder width,i EMG and RMS ratios of badminton and football groups were much higher than those of ordinary people and basketball groups,and the difference was statistically significant(P<0.05).The ratio of i EMG and RMS in badminton and football at 1.5times shoulder width was still higher than that in ordinary people and basketball,and the differences in patterns 10,11,12 and 13 were statistically significant(P<0.05),there was no significant difference between the 3 groups in modes 14,15,16,17 and18(P>0.05).Conclusion:1.The VMO /VL EMG ratio of badminton and football students was significantly higher than that of the other two groups.2.When it came to activating vastus medialis muscle in squats,the general population and basketball-specific students chose 1.0 shoulder width,knee bend 45 °foot neutral or 1.0 shoulder width,knee bend 30 ° foot internal rotation.The best EMR data for badminton and football-specific students appeared at 1.0 shoulder width and knee bend 30 ° foot external rotation.3.In squat to coordinate the balance of vastus medialis muscle and vastus lateralis muscles,basketball students should choose an angle of 30 or 45 degrees outside of their foot with 1.0 shoulder width,while badminton and soccer students should adopt a 1.5 shoulder width,a 60 degree squat angle and keep their foot neutral.