The "Total Recall" star, who is engaged to Justin Timberlake, said she is a survival expert and knows how to stop hypothermia developing, reported Contactmusic.
"My father taught me to be a survival expert. I know how to prevent hyperthermia if you fall into a freezing cold river; you get out and immediately take off your clothes.
"The best way to heat up your body is to have skin-on-skin contact with someone. So basically, you're both naked," she said.
Biel, 30, credits her parents as the closest people too her in her life, mostly because of their 'outdoorsy' nature.
"Who have I been closest to in my life? My parents. They are very cool outdoorsy people. Growing up, we always camped as a family in Colorado, where we lived. My dad taught me all this survival stuff, like starting a fire and building a shelter out of trees and branches."
