Study On The Characteristics And Morphological Changes Of Female Breast Movement In A Long Running

In the existing domestic breast health and sports bra related research,most of the test time is in 3-5min,,which is not consistent with the exercise time of women in daily life.The majority of women's exercise time in daily life is more than 30 min,so this study will explore the characteristics and morphological changes of female breast movement during a long run.Objective: This study is expected to explore whether the motor characteristics of women's breasts can be changed before and after a long running exercise.Explore whether,in the initial and final stages of a long exercise,a woman's breast form changes and what the cause of the change is.It provides a theoretical basis for the future development of sports bras for female athletes.Methods: 8 female subjects with exercise habits,wearing the same model of experimental sports bras,tights and sneakers running on a treadmill.(1)Experiment one: The subjects wore sports bras,on the treadmill for more than 30 min,the speed of 8-10km/h running,the start of the run 5min and the final end of the 5min speed of 10km/h.(2)Experiment Two: The subjects in the naked chest state on the treadmill for 5min,the speed of 10km/h running.The kinematics data of 5min were collected at the beginning and before the end of the motion,and the morphological characteristic parameters of bare chest were in the static state before and after exercise.Collect all the kinematics data in experiment two.The motion characteristics and morphological changes of breasts in the early stage of a long period of exercise and in the later stage of exercise were calculated by kinematics data.Results: The morphology of the breasts changed when the static state before and after exercise,and the position of the breasts was lower,inward and forward.Compared with the early stage of exercise,there was no significant difference in the displacement of sternum angle point before and after,left and right,upper and lower direction.However,in the early and late stage of exercise,the movement characteristics of the breasts changed,and the movement amplitude of the breasts in the late stage of exercise was significantly increased in the anterior and lower directions,and increased in the left and right directions,but there was no significant difference.The trajectory of the breasts in the later stage of exercise was 17.92% higher than that of the early stage of exercise during a gait cycle.There was no significant difference between the maximum Lyapunov index of upper and lower breast upward movement in the early stage of a long exercise,which was chaotic.Changes in breast kinematics characteristics may be caused by changes in breast morphology.Conclusion: In a long run,the morphology of female breasts changes in the early stage of exercise compared with the late stage of exercise,and the main changes are the sagging and inner of breasts.In a long run,there was no significant change in the kinematics characteristics of the sternum angle compared with the late stage of exercise,but the kinematics characteristics of the female breasts changed,and the values of the total length and displacement of the female breasts were larger,and there was significant improvement.The offset amplitude of each direction indicator also becomes larger.Women should choose high-intensity exercise bras to protect their breasts and prevent damage to breast tissue during long periods of exercise.