# 肱三頭肌(Triceps)

在人體的上肢部位中，肱三頭肌是最重要的肌群之一。它是位於手的上臂部後方之肌群，主要功能是手臂對於外物的推撐用力作用，以及協助胸部肌群對外界的運動。

一般而言，我們針對肱三頭肌的訓練，通常是伴隨於胸部肌群之後，才施於訓練處方。這是因為「先訓練大肌群，再訓練小肌群」的原則，不然的話肱三頭肌將因先訓練而提早衰竭，使得因為手臂沒力氣，那麼更別提實施胸部肌群訓練了。

**肌肉起止點：**

長頭：上側起於肩胛骨盂下節結，下側止於尺骨鷹嘴！

外側頭：起於肱骨大結節下方後外側表面，止於尺骨鷹嘴！

內側頭：起於肱骨後表面（在裡面），止於尺骨鷹嘴！


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