Analysis Of The Kinematic Features About The Curve Running Technology In The First Corner Of The Outdoor 400-meter Standard Track And Field

Objective: in order to improve the athletes' understanding of the curve running technique and to improve the performance of sprint 400 m,the kinematics characteristics of the athletes' running technique in the first curve of 400 m were analyzed.by studying and analyzing the kinematics characteristics of the first bend running technique in the outdoor 400 m standard field,it is helpful for the athletes to better understand the curve running technique and to provide some theoretical data for the coaches.At the same time,it provides some kinematics indexes and scientific basis for curve running training,and strengthens the scientific degree of training.Methods: the methods of literature,experiment,mathematical statistics,analysis and comparison were used in this paper.During video recording,two cameras are required to synchronize,and the students who take part in the test are shot in a sprint.Result:1.In the first curve of 400 meters,the step capability index is below 1.2,and the step frequency capability index is more than 8.After the radius is increased,the step length is increased properly on the basis of the original step frequency.2.The center of gravity of nine second-level sprinters of Xi'an Institute of physical Education is 8.119m/s-9.055m/s in the first curve of 400 m.With the increase of radius,the speed of gravity center moves is increasing.The inward inclination of the body tends to increase.Athletes' performance is relatively better.3.At the moment of pedaling at the end of the bend,the specific state of the swing arm of the athletes investigated in this paper is as follows: the angle between the left arm and the right arm is 34 °-48 °,and the amplitude of the right arm angle is between 37 °-58 °.In the 400 m first bend,whether in the first,third or fifth track,the mean velocity of left hip is smaller than that of right hip,and the difference is within 1m/s.4.At the moment of landing buffer,the angle of the knee joint of the supporting leg is small,the angle of the back flexion of the ankle joint is larger,the angle of the knee joint of the swing leg is about 47.86 °,the angle of the back flexion of the swing leg is about 118.43 °,the angle of the knee joint of the supporting leg is small and the angle of the ankle joint is small at the moment of vertical support.The knee joint angle of swing leg is about moderate,the angle of ankle joint dorsoflexion is about 108.43 °,the angle of knee joint of supporting leg is decreased,the angle of back flexion is about 106.37 °,the angle of knee joint of swing leg is 52.96 °,and the angle of ankle joint dorsoflexion is reduced to 106.30 °.Conclusion:1.Nine runners of the Xi'an Institute of Physical Education ran at the first corner of an outdoor track and field track 400 meters.From the first runway to the fifth runway,the step length increased and the cadence decreased.The angle of body tilts inwards is larger and larger.The center of gravity moves more smoothly.In terms of the degree of advantage,the fifth track has the greatest advantage.The first road has the least advantage,and the third road is relatively moderate.2.In the course of the end of the curve after running in the corner,the swing amplitude of the left arm of the athlete in the first lane,the third lane,or the fifth lane must be smaller than the amplitude of the swing of the right arm,and the angle between the left upper arm and the trunk is smaller than the angle between the right upper arm and the trunk.The average speed of the left hip is less than the average speed of the right hip.3.During the period of time when the ground is supported on one foot and the moment of falling,due to the ground reaction force,the athlete's legs are under greater stress.Swing leg knee angle is too small,and the dorsiflexion angle of the ankle is larger.In the vertical support moment,the support leg and knee joint are basically moderate,and the ankle joint dorsiflexion angle is large.At the moment of the back force,the force and bending angles of the joints of the legs are similar but different from the momentary support of the single foot.The difference is that the angle of the dorsiflexion of the ankle is moderate.