收紧腹部及全身松弛肌肉。

Contract abdomen and all loose muscle throughout the body.

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提举或者放下物体的时候收紧腹部肌肉；

Tighten your stomach muscles as you lift the object or lower it down.

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检查一下你的前侧肋骨下部不要明显地向天花板的方向突出，收紧腹部并伸展下背部。

See that your lower front ribs aren't protruding sharply toward the ceiling, which hardens the belly and compresses the lower back.

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