力ちからが抜ぬける

expression, ichidan verb

lose strength; become weak; go limp

Describes physical or mental strength draining away, often suddenly or due to relief, shock, or exhaustion. Can refer to body parts going limp or a general feeling of weakness.

• 緊きん張ちょうが解とけて、全ぜん身しんの力ちからが抜ぬけた。

  The tension left me and my whole body went limp.

• その知しらせを聞きいて、彼かれは力ちからが抜ぬけたように座すわり込こんだ。

  Upon hearing the news, he sank down as if all strength had left him.