The Analysis Of The Characteristics Of The Upper Body Posture In Different "Outside Practices" Of Ballet

At present, the basic training methods of ballet are widely used in the physical training, but the knowledge of their functions is from the perspective of research on the ballet arts, and there is little research reported that how the physical training with different outside practices in basic training of ballet will affect the different results of the steady upper body posture. For the practical needs of physical training, according to the theory of sports anatomy and basic principles of aesthetics, using the method of biomechanical analysis, and with the measurement of the physical forms of the students and the analytical tools of sEMG, this paper studies the activities of the trunk muscles and the posture change of the body with different outside practices of 15 female college students.The result shows that the curvature of the thoracic vertebra changes very little while the shape of the chest is tending toward unfolded and straight on three different foot positions of outside practice, and the basic standing of ballet with lower limbs turning outside is helpful to strengthen the related muscles and thereby improve the form of the body; that the motor units of most muscles mobilize on a higher level during the outside practice of basic standing of ballet which needs willpower to maintain the equilibrium of the gravity centre when keeping the two feet on a straight line with the two heels met together, particularly, there are more motor units of muscles which are enlisted to mobilize among all the tested ones during the half or fully squatting exercise; and that the angle of inclination of sacrum significantly increased and lordosis also increased accordingly during the basic standing of ballet, which are related to the ability of controlling the gravity centre and the hip flexibility.It concludes that as the angle formed by the two feet opens wider, the upper body posture is tending toward the more unfolded and straight; that the buttocks stick up as the angle of inclination of sacrum and lordosis increase when it needs willpower to keep the two feet on a straight line with the basic standing of ballet; and that while doing the half and fully squatted exercises, the exercise is useful to increase the lower limb muscles power and helpful to the physical form improvement..The paper also suggests that the exercisers should practise the basic standing of ballet as the basis of physical training, and meanwhile should practise it with the increasing angle formed by the two feet; and they should increase the lower limbs flexibility of turning outside and should have a mind to reduce the angle of inclination of sacrum at the same time, and therefore to extend the spinal more fully, to strengthen the related muscles, and to gain and keep a nice body and posture.