Kinematic Analysis Of The Bounce Technique Of The Samba Forward Bota Fogo

Based on the kinematic perspective,this study aimed to explore the kinematic rules of bouncing technique initially by comparing the kinematic characteristics of Samba Forward Bota Fogo bouncing technique of 12 Latin dance special athletes（divided into high level and normal level groups）from Xi’an Physical Education University,and to provide reference for normal level athletes to further improve their bouncing technique.This study mainly adopts the kinematic test method,by collecting the original kinematic parameters of 12 test subjects during the Forward Bota Fogo bounce to provide for the analysis of sports technology characteristics;The raw data in this paper were sorted and functionally calculated using Excel 2019,and Independent Sample t-test was conducted by SPSS26.0,as a way to dig deeper into the differences of the relevant indicators between the two groups of athletes,which can be conveniently used to guide the writing of this paper.Research Results:1.In the forward Bota Fogo movement,the total time spent in the high and normal level groups was1.99±0.34 s and 1.84±0.25 s,respectively,with no significant difference between the two groups,but there was a difference in the time allocated to the bounce,with a highly significant difference in the time spent in the bounce accumulation phase.2.During the bouncing accumulation phase,the body weight displacement of the high-level group in the anterior-posterior and vertical directions was 0.032±0.086 m and 0.005±0.005 m,respectively,and during the bouncing out phase,the body weight displacement of the high-level group in the horizontal and left-right directions was 0.133±0.063 m and 0.179±0.093 m,which differed from the comparison of the normal horizontal group.3.The starting velocities of the three joints of the lower limbs in the bouncing stage were hip,knee and ankle joints in the high level group and the normal level group from the largest to the smallest,in which the starting velocities of the three joints of the main leg in the bouncing storage stage were0.15±0.11m/s,0.11±0.07m/s,0.10±0.10m/s,which were different from those of the normal level group;the starting velocities of the hip and knee joints during the bouncing out phase were also different from those of the normal level group.4.The knee joint angle of the dominant leg in the high level group was from large→small→large→small→large→large→large during the bouncing process,and there was a general difference in comparison with the normal level group.5.The shoulder-hip torsion angles of the high level group were 43.18±13.65° and 53.52±21.94° at the beginning moment of the two bounces,16.72±5.99° and 18.67±2.09° at the moment of the intersection of the main and power legs,respectively,and 24.21±2.58° and 17.58±3.36° at the end moment of the bounces,respectively,except for the beginning moment of the second bounce when the shoulder width torsion angle was not different from that of the normal horizontal group at the beginning moment of the second flick,except for the significant differences at all other moments.Research recommendations:1.Average level athletes generally take less time than high level athletes to build up force during the bouncing phase,and take longer to extend the knee joint during the bouncing phase than high level athletes,so the bouncing rhythm is less controlled.2.The high level group had smaller displacement of body weight in horizontal,left and right and vertical directions during the bouncing phase,while the speed of body weight in horizontal and vertical directions was smaller,the trunk was more stable in control and the bouncing technique was completed more smoothly.3.In the bouncing accumulation stage,the high level group lower limb three joints start slow,which is conducive to fully demonstrate the bouncing process,and in the bouncing out of the foot stage hip and knee movement speed,which is conducive to increase the sense of bouncing explosive.4.High level athletes generally have more reasonable control of the hip,knee and ankle joint angle changes,sufficient flexion and knee storage,large stirrups and extension forces,large joint amplitude changes,and more fluid in the articulation of the bouncing technical movements.5.High level athletes have positive shoulder and hip torsion,the torsion angle is the largest at the beginning of the bounce,which is conducive to the torso force to further amplify the leg force and speed of the bounce through the knee stirrups;the shoulder and hip torsion angle is small at the moment of the completion of the bounce,the pelvis inward amplitude is large,and the vertical feeling in the middle section is more obvious.