Why does the human body initiate shivering when exposed to a cold environment, even though muscle contraction consumes energy and could exacerbate heat loss?

💡 Explanation

Shivering generates heat through non-shivering thermogenesis via futile cycling, a process of rapid muscle contraction and relaxation; because ATP is hydrolyzed without producing mechanical work, therefore, heat is released, rather than conserving energy through other mechanisms.

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