“It’s amazing what your body will do when you jump into the ice.”

In the beginning of November United States Marines, 170 of them, challenged their bodies to its boney core by taking part in frigid training in the country where they’re currently stationed: Norway.

The exercise went like this: their instructors cut a hole in the middle of a frozen pond’s ice, and guided the military members to do one thing. Jump in. When they emerged after a short while, other Marines were tasked with making sure they took the proper precautions to avoid hypothermia.

“Your body naturally pushes everything to your core so you don’t feel as cold as you mentally thought you would feel walking up to the ice.”