The arm and shoulder rotation stretch warms up the muscle that surrounds the shoulder jointed the body. These muscles are used continuously during swimming.

手臂和肩膀的旋转伸展动作帮助肩部及其联接躯干的肌肉群充分热身。游泳时将连续不停的运用这些肌肉。

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At most, body rotation is in the vicinity of 45 degrees to either side and the length of stretch forward is determined by the amount of time available to execute the stretch.

至多，身体转动是在每一侧的45度时，而向前伸展的长度则是由伸展完成的时间所定。

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Finally, through the approximate analysis, the approximate representation on the rotation tensor and stretch tensor is proposed.

最后通过近似分析，给出了在小变形中等转动情况下转动张量和伸长张量的近似表示。

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