The function of forward-leaning leaving board and swinging of the swinging leg on takeoffs in long jump;

On left-leg movement in technology of shot push with back turn;

Three dimensional kinematics analysis on the swing leg support technique before taking off for Chinese elite male high jumpers;

Technical principles of back style swing leg movements;

It analyzed that different swing legs swing the influence of the result to take-off of angle,the result shows the angle of swings the leg to swing directional control about 10-20 degrees,take-off result to be better.

The swinging of the swinging leg in dash & the technigue of the decrease of momentum;

The results reveal that the poor effect of male volleyball players single foot takeoff accounts for their weak eccentric contraction capacity of takeoff leg s knee extensor and poor swinging technique of swinging leg, which lead to long buffer time and slow buffer speed of takeoff knee, as well as slow swinging speed of swinging leg.

The positive action of free leg, quick extending and swing forwards can take good advantages of running velocity and be greatly helpful to the big increase in vertical velocity of the center of gravity.

The mechanism of JVC high-speed photographic system was used to study the kinematic characters of the free leg at the supporting phase of running at full speed after start in the 100m male runners in the 1999 China National Track & Field Championship held in Huizhou.