A hiker stranded in a blizzard experiences extreme hypothermia. Why does shivering become less effective below a core body temperature of 30°C (86°F)?

💡 Explanation

Shivering effectiveness declines at very low temperatures because the hypothalamus, the body's thermoregulatory center, becomes significantly impaired. Therefore, it is less able to stimulate muscle contractions for heat generation, rather than glycogen catabolism or maximum heat output from brown adipose tissue being the primary limiting factors.

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