Sport Science

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 The Sport! Science Faq

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All Questions are from the publication The Sporting Life unless otherwise indicated.

 

This list was last updated May 15, 1997

 
Click me to find out the answer  Why do my muscles sometimes burn when I'm excercising?

Click me to find out the answer  Why do I feel sore the day after I exercise?
Click me to find out the answer  What happens to my heart when I exercise?
Click me to find out the answer What is "VO2 max" and how does it measure cardiovascular fitness?
Click me to find out the answer What's the best position for my hands when I swim freestyle?
Click me to find out the answer How high can you jump?

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Why do long jumpers "run" several steps in the air after they take off?

 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.

Click me to find out the answer How does ice help a sprained ankle or other injury?
Click me to find out the answer How important is my grip on the bat when I'm striking the ball?
Click me to find out the answer  Why does spinning a ball make it curve?
Click me to find out the answer How does Michael Jordan manage to hang in the air for so long when he goes up for a slam dunk?


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