What matters in an extreme environment like Patagonia, is not so much your rate of cooling as much as the final temperature that your body drops to. Mariano seems to have figured this out. He absolutely needs to keep his body insulated to maintain his core temperature, but not so much his head. Experience had taught him that all he needed was an amazing sleeping bag. Next time I’m getting one.
You can hear more Medical Myths on Health Check on the BBC World Service.
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