Muscles spanning the upper back, the middle trapezius and rhomboids, pull the shoulder blades towards the spine to open the front of the chest.

中斜方肌和菱形肌(贯穿上背部的肌肉)将肩胛骨向脊柱的方向拉，从而打开胸廓。

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Inhale and lift upper back using back muscles while moving forearms outward until parallel.

吸气并用背部的肌肉抬起上背部，同时移动前臂向外直到平行。

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Draw your hands back behind you so your elbows are down and your upper back muscles are squeezed together.

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