The Polar Plunge is this weekend; here’s what you need to know about what this “fun” challenge does to your body.
To the adventurous, jumping into icy cold water in the middle of winter may sound like a good way to raise money for charity. But the Polar Plunge can also affect your body — from your lungs and heart to your muscles and skin.
Fortunately, perhaps the biggest fear associated with being in cold water — hypothermia — doesn’t set in until you’ve been immersed in cold water for 30 minutes, says Paul Gabriel, M.D., Grant Emergency Department Medical Director. “So Polar Bear Plunge participants probably do not be concerned with hypothermia with limited cold water exposure,” Gabriel says. We talked with Gabriel about the ways the plunge can affect your body — plus some tips on staying safe.
“The most important issue is called the ‘cold shock response,’” which refers to the first minute after you get into cold water, Gabriel says.
“It first affects breathing. There is an automatic gasp reflex that occurs in response to rapid skin cooling,” Gabriel says. “The second cold shock response is hyperventilation. This normally will pass after a short time, but can lead to fainting if panic occurs.”
“The third cold shock response is vasoconstriction, which narrows the arteries and makes the heart work harder,” Gabriel explains. “Sudden cold immersion also affects the heart’s electrical conduction and can cause cardiac arrhythmias and potentially cardiac arrest.”
Skin and Muscles
You know how you shiver in cold water? There’s a physiological reason for that.
“Vasoconstriction decreases blood flow to the skin and muscles, preserving flow to the vital organs, the heart and brain,” Gabriel says. “This initiates our shivering response in an effort to increase body heat.”
“Continued cold water immersion leads to confusion, impaired judgement and eventually coma,” Gabriel says.
So don’t stay in the cold water longer than you need to.
Staying Safe and Warm
When it comes to safety, “common sense is the best bet,” Gabriel reminds. Here are some of his tips:
- Layer and wear warm clothes, including gloves.
- Limit the time of cold water contact to under 15 minutes — ideally less than five.
- Don’t immerse your head under water.
- As soon as you’re done with the plunge, dry off completely and change into warm dry clothes.
Want to talk to a doctor about the Polar Plunge? Find one here.