The hitch-kick, as the running motion is called, stops the forward
rotation of the jumper's body that he gets when he springs into the air.
As the jumper plants his foot for takeoff, the motion of his lower body
stops for the fraction of a second his foot is in contact with the board.
But his upper body continues to move forward, which makes him start to rotate
forward around his center of gravity. If unchecked, this rotation would
send him face-down into the sand.
Long jumpers have learned to counteract this rotation by moving their
hands and arms in the hitch-kick. During the hitch-kick, jumpers hold each
leg straight as it moves backward and bent at the knees as it comes forward.
This difference in leg position causes the jumper's lower body to move forward.
Similarly, the jumper's arm movements during the hitch-kick pushes the
jumper's upper body backward. These body motions neutralize the takeoff
rotation and allow the jumper to get into a better position for landing
When the jumper stops hitch-kicking, the takeoff rotation continues unchecked.
The jumper rotates forward around a line that goes from side to side through
his center of gravity. This rotation forces his legs (now stretched out
in front of him) downward.