Why do we shiver when cold?

Answer: Muscles contract to generate heat

Muscles contract to generate heat ✓ — Correct! Shivering is your body's automatic response to cold, controlled by the hypothalamus. When body temperature drops, your brain triggers rapid muscle contractions. These involuntary movements burn energy and generate heat through friction and metabolic activity. Shivering can increase heat production by up to five times, helping maintain your core temperature at 98.6°F (37°C).

Nerves are misfiring from cold — Wrong. Shivering isn't a nerve malfunction—it's a precisely controlled warming mechanism. The hypothalamus deliberately triggers muscle contractions to generate heat through metabolic activity.

Muscles tense to conserve heat — Wrong. Simple muscle tension doesn't generate significant heat. Shivering involves rapid, repeated muscle contractions that burn energy and produce heat as a byproduct, actively warming the body.