| Research purposes:Based on C507 difficulty movement of aerobics sports biomechanics research, discusses the basic characteristics and regularity, thus promoting the aerobics, perfecting the system theory and provide theoretical basis for scientific training.Research methods:Using two nissan panasonic NV-MD9000 fixed, fixed-focus camera, spacer way synchronously (external synchronous), exposure time of 1/500 sec, frequency for 50 cycles per second. To analysis and evaluation the test object technology moves and 3d images analytical data.Research results: (1) The athletes finish C507 difficulty movement used 3.660 sec total time. Take-off stretching time for 0.220 seconds, and emptied of body gravity for 0.660 seconds (including rise time for 0.260 seconds, down time for 0.400 seconds), support for ground buffer time is 0.960 seconds. (2) In the C507 difficulty movement process, body weight change displacement is lesser in the direction of Y axis.That show about body shaking little amplitude. Take-off to landing on the displacement of the body is only for 0.222 meters on the X direction. Body gravity in the maximum displacement on the Z direction to 1.357 meters.(3)The X direction of maximum speed of body gravity is 1.652 m/s, which is mainly run-up phase change;The maximum speed in Y directions for 0.655 m/s, little amplitude;Take-off in the Z direction on the maximum velocity value for 2.562 m/s, the body touch down when 3.867m/s for maximum velocity. (4) The speed of two leg knee change fluctuatly in trend. The largest amount change which are during take-off stage and suspension, and the bowed legs than straight legs. Knees and legs leg knee unbend of maximum speed for 4.081 m/s and 4.831 meters per second, are rising in suspension.(5) The speed of leg unbend the ankle have the largest amount change during take-off stretching stage and emptied stage, phase change emptied rise in 2.200 emptied when 6.887 maximum speed/sec.Due to the athletes in the runup stage adopts single feet and legs jump approach will, so at this stage knees leg unbend leg change faster than the ankle. Bowed legs ankle speed achieve maximum 4.261 meters per second in 2.160 seconds to vacate the rise. (6)The ankle in take-off cushioning and take-off stretching two stages, the biggest change at 85°~ 160°. Left, right knee moments in the Angle of buffer for 80°and 88°, the maximum height in suspension for 170°and about 50°probably. Right and left hip be to the minimum when the gravity to the highest.The main conclusion: (1) when the athletes finish C507 difficulty movement, the control accuracy, body posture, every action legible action link between compact, coherent. But because of lumbar abdomen muscle power shortages, so physical control ability is poor when landing in the buffer. (2) Using slant in the process of takeoff stretching influence take-off on the speed, height. Also due to less of lumbar abdomen muscle strength and arm strength leads to ground buffering time is too long, and later the connection and unfavorable movement rhythm. (3)the body was small displacement in the direction of movement , Athlete jumps direction of force and upper limb swing range perfect . (4)The maximum speed of body gravity is 1.853 meters per second in the run-up stage by x direction. The Y direction of maximum speed about body gravity in take-off buffer stage, reached 1.028 m/s. Jump for maximum speed on Z direction is 2.717 m/s, but the body gravity decline of displacement, longer than rise. So the body touch down the maximum velocity value reached 4.057 m/s, greater than the speed of the take-off significantly. (5)She had good attitude control body air, reached the rules,from the ankles, knees, hips angle. But left and right knee buffer corresponding to the small Angle in the biggest moments,so that cause take-off time long, low altitude suspension, The body thrust not fully extended when two hip Angle in take-off stretching stage from the ground, then affecting the height of suspension.
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