Blood Flow Restriction Intervention Combined With Low-intensity Squat On The Lower Extremities Of Sprinters The Effect Of Post-activation Potentiation

[Research objective]:Post-activation Potentiation（PAP）is a currently hot research issue and is widely studied at home and abroad.For induction of PAP load strength,experts and scholars generally hold that the greater the load strength of given organism,the more obvious the PAP effect.However,greater load not only increases the risk of injury,but also fails to induce PAP due to excessive fatigue.But the blood flow restriction（BFR）can not only preferentially recruit more Type II muscle fibers,but also have a special mechanism of producing heavy load training traces on the body with a small load.The purpose of this study is to verify the effect of blood flow restriction intervention on post activation enhancement effect on the basis of experiment,and find a more effective way to induce post activation enhancement effect.[Research method]:The experimental method is mainly adopted in this paper,of which,12 subjects are sprinters.The sports grade is grade II or above.In the experiment,all subjects are intervened in three different ways to induce PAP: 45% 1RM6 times\group * 2 interval 60 S,120mmgh45%1RM6 times\group * 2 interval 60 S and 80%1RM3 times\group * 2 interval 2min.The data of 30 M,standing triple jump,vertical jump touch height and isometric muscle strength are collected at six recovery time points of 1min,4min,7min,10 min,13min and 16 min after induction.[Research conclusion]: 1.Combined with the experimental data,it is concluded that the subjects could not induce PAP after 45% 1RM weight-bearing squat intervention;2.Blood flow restriction combined with low load squat intervention（120mmgh+45%1RM）can induce PAP,which has a significant impact on the subjects’ 30 M performance in 7-13 minutes respectively.The performance in 7-16 minutes has a significant effect on the subjects’ standing triple jump performance.The performance in 4-10 minutes has a significant effect on the subjects’ vertical jump and touch height.The performance in 7-13 minutes has a significant effect on the isometric contraction（anterior group）muscle strength of the subjects.Subjects can induce PAP through 80%1RM weight-bearing squat intervention,which has a significant impact on subjects’ 30 M performance in 4-16 minutes respectively.The performance in 4-10 minutes has a significant effect on the subjects’ standing triple jump.The performance in first 7 minutes has a significant effect on the subjects’ vertical jump and touch height.The performance in 1-16 minutes has a significant effect on the isometric muscle strength（front group）of subjects,and the performance in 10-13 minute has a significant effect on the isometric muscle strength（rear group）;3.Blood flow restriction combined with low load squat can induce PAP.In terms of the duration of PAP activation,the duration of PAP induced by 80%1RM weight-bearing squat intervention is longer in 30 m and isometric muscle strength（front group）,and the duration of PAP induced by 120mmgh+45%1RM weight-bearing squat intervention is longer in standing triple jump test.4.Comparing the PAP intensity of 80%1RM and 120mmgh+45%1RM intervention,it can be seen from the P value that there is no significant difference between them.