On pool deck, swimmer bends forward and practices arm action.

站在泳池边，运动员向前弯曲，同时作蝶泳移臂的动作；

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The right image shows a more effective position at the completion of the arm entry. The leverage is improved so the swimmer can immediately begin to generate substantial force.

下图显示了一种更有效的入水方式，手臂处于这个位置，背阔肌对手臂的杠杆作用大大提高(力矩增加)，选手能立即产生很大的力量。

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Flippers allow the swimmer to concentrate on arm technique because it improves the efficiency of each kick, helping to maintain momentum.

允许游泳运动员的鳍状肢臂技术集中精力，因为它能有效运作的每一踢，帮助保持发展势头。

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His compatriot Natalie du Toit, a single amputee swimmer, and Natalia Partyka, a Polish table tennis player who was born with one arm ending just below her elbow, competed at both the Olympic and Paralympic Games in Beijing.

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