Because force is generated with help from the ground, bending your knees places your body in better position to produce trunk, hip, and shoulder rotation.

因为力量源自地面，弯曲你的膝盖能让你的身体处于一个更易通过躯干，髋和肩部转动获得能量的绝佳位置。

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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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Rotation is due to shoulder roll.

转动是由于肩的转动使然。

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Even with her tiny arms she has incredible arm reach and rotation in her shoulder joints.

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He missed a start March 21 because of a shoulder impingement and missed another turn in the rotation this week after experiencing neck pain during a bullpen session Monday.

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Lilly tossed five effective innings in his first start since shoulder surgery, giving the Dodgers' injury-depleted rotation a boost.

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