This Diver Saw a Frozen Lake…You Won’t Believe What He Did Next [VIDEO]

Oh the weather outside is frightful — but that didn’t stop this diver!

In this video we see Petr Kapoun free diving under ice that covers Lake Milada. This reservoir in the Czech Republic may look like a pond, but it’s actually around 50 feet deep. The water only looks shallow because it is crystal clear!

You may be thinking that Petr is a little crazy, but winter swimming is actually a tradition that goes back centuries in Eastern European countries like Russia and the Czech Republic. In Scandinavian countries, sauna-goers often plunge into cold water after a long stay in the steam rooms to cool down. There are even international competitions for winter swimming!

Don’t take this stunt too lightly however. Petr has extensive experience with ice swimming and brought along a buddy both to film him and to help him if he needed it, as you can see from the rope beneath the ice. If you’ve ever jumped into a cold pool or done the viral ice-bucket challenge, you know the feeling of the convulsive gasp your body takes in response to the sudden shock of cold water. This can be followed by hyperventilation, which makes it a lot easier to accidentally breathe in water — more commonly known as drowning.

Drowning isn’t the only potential risk. If you stay in the cold water for too long, the blood in your limbs cools down, and when it returns to your heart it can cause spasms and even a heart attack. If you don’t fall prey to either drowning or heart failure, hypothermia is another hazard. It can take as little as thirty minutes in freezing water before the body temperature drops to hypothermic levels. Symptoms include shivering, mental confusion, and cardiac arrest.

So enjoy this video of Petr’s amazing icy free dive, but don’t try it for yourself without training first!