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SWIMMING
Goal: How to maintain the fastest possible swimming speed.
Free-body diagram of a swimmer:
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head, trunk ———> receive resistive forces
arms. legs ———> receive propulsive forces
Propulsion is produced through drag, but also through lift.
Breaststroke:
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Lift and drag forces exerted on hands in the breaststroke:
In the breaststroke, propulsion is achieved through lift forces.
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Treading water:
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Front crawl (“freestyle”):
In the front crawl, propulsion is achieved through a combination of lift and drag forces.
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To swim fast:
maximize propulsive forces on arms and legs
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pull hands hard through the water; push back water with legs
minimize resistive forces against head and trunk
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keep trunk well aligned with direction of race