Effect Of Six-Week Sand Plyometric Training On The Explosive Power Of The Hip Joint Of Sportsmen

Objective: The purpose of this study was to investigate the effects of different surfaces on the explosive power of hip joints in sportsmen after 6-week plyometric training and the reason why the training increased the explosive power of hip joints.Methods: Sixteen sportsmen were randomly divided into the sand training group(8individuals)and the hard ground training group(8 individuals),they completed 6-week sand ground plyometric training and hard ground plyometric training respectively.The infrared motion capture system was used to test the changes in kinematics indexes related to the subject’s one vertical jump and six consecutive vertical jumps before and after training,and the isokinetic dynamometer was used to test the isokinetic strength of subject’s hip joints at 60 ° / S and 240 ° /S.Results: After 6-week plyometric training,the one vertical jump height of both the sand and hard ground training groups increased significantly(P <0.05);there was no significant difference between the buffer angular velocity of the subjects’ hip joint before and after training(P> 0.05)and so was the landing angular velocity of the subjects’ hip joint(P> 0.05).The height of 6 consecutive vertical jumps of the sand training group was significantly higher than the hard ground training group after 6weeks of plyometric training(P <0.05).Isokinetic strength test results show that the effect size of relative peak torque of hip flexor muscles at 60 ° / S in the sand training group is higher than that in the hard ground training group after training(0.97> 0.41),and the effect size of relative peak torque of extensor muscles is also higher than in the hard ground training group(1.35> 0.82).Conclusions: 1.Using plyometric training on both the sand and hard ground surfaces can enhance the explosive power of the lower limbs and hip joints of sportsmen 2.Compared with the hard ground surface,using plyometric training on the sand surface is more beneficial to improve the continuous explosive power of the hip joint.3.The sand surface has a better effect on the protection of hip joint sports injuries than the hard ground surface.