Experimental Study Of The Effect Of Athletic Fatigue On The Landing Of Dominant And Non-dominant Side Leg Vertical Jump In College Students

Research purposes: This study makes a comparative analysis of the biomechanical characteristics of the landing movements of the dominant and non dominant side legs of the lower limbs,and explores whether there are differences between the two sides of the lower limbs in the fatigue state and the size of the differences.It provides some theoretical basis and reference value for guiding college students to exercise,preventing sports injury and prolonging sports life.Research methods: eight healthy male college students were selected as experimental subjects.First,the dominant side and non dominant side legs were evaluated: the subjects jumped five times in a row,and the landing stage with the highest height of center of gravity and the best performance was selected for analysis.Secondly,quintic motion capture analysis system and three-dimensional dynamometer are used to collect the relevant data of kinematics and dynamics.Finally,through paired sample t-test comparison,the changes of biomechanical indexes of both lower limbs of vertical jump landing after fatigue were obtained.The results were as follows :(1)the fatigue state of the dominant side and the non-dominant side legs increased the landing and buffering time,and the dominant side had a significant difference(P<0.05).(2)In the fatigue state,there were significant differences in ankle angular velocity,knee angular velocity,knee flexion angle,ankle dorsiflexion angle,ankle dorsiflexion peak torque and knee extensor peak torque between the dominant side and the non dominant side(P<0.05).The torque of hip,knee and ankle joints of both legs decreased.(3)In the fatigue state,the dominant leg first bears a large load.The change of the symmetric exponent of vertical ground reaction force and load rate shows that the non-dominant side and the dominant side leg have laterality and asymmetry,and the second peak value of the dominant side and the non-dominant side leg has significant change after fatigue(P<0.05).However,there was no significant difference in load rate between dominant and non dominant limb(P<0.05).Conclusion: there is asymmetry in the lower limbs,and the choice of landing strategy will be affected by the laterality of the lower limbs in the process of movement,so the unilateral lower limbs can not be selected to represent the landing stage changes of the two lower limbs in the study of bilateral jumping.After fatigue,the change of three-dimensional force peak value and joint angle in the vertical direction of both legs showed that the dominant side first suffered a large ground reaction during the movement.The dominant side is more prone to sports injury than the non dominant side in landing stage.When college students exercise their leg muscles,they can choose different exercise methods and exercise loads according to the dominant and non dominant limbs.