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 November 12, 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 to closeWhat's the best position for my hands when I swim freestyle?
If you learned to swim before the mid-1970s (and maybe later, depending on the coach), you were probably taught to pull your hand straight backward through the water like a canoe paddle. With this stroke, you move forward by pushing against the water. It turns out that's not the best way to propel yourself through the water. Today's swimmers learn to follow an S-shaped pattern (see diagram below), a more natural motion that has more in common with a propeller than a paddle.

 

With the S-shaped motion, the edge of your hand splits the water flowing past it into two streams, much like what happens when an airplane wing cuts through the air. Some water goes over the back of your hand and some goes under it. This split generates a lift, which propels you forward in the water, similar to the way a propeller's wing-shaped blades push a boat forward.


We tend to think of lift in terms of moving you upward (as is the case with an airplane), but lift can be generated in any direction, depending on the orientation of the hand (or wing) that creates it. Expert swimmers continuously adjust the angle of their hands throughout the stroke to maximize the forward-directed lift. This lift means a swimmer can go faster with less effort using the S-shaped stroke. You can almost "fly" through the water.

 Swimming Diagram
Click me to find out the answer How high can you jump?
Click me to find out the answer Why do long jumpers "run" several steps in the air after they take off?
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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