Why does the human body shiver?

When your body does become too cold, its automatic response is to tighten and relax the muscles in rapid succession to warm up. This is also known as shivering.

The human body shivers as a way to regulate body temperature. When it's cold outside, you might starts shivering, and that's your body's way of warming up. It rapidly tightens and relaxes your muscles for warmth.

Explanation:

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