Cold water facts: What every winter swimmer & paddler should know

More and more people are enjoying watersports in the wintertime. The cool air, the calm atmosphere and the quietness makes winter paddling so attractive. And of course, if you are a SUP racer or truly addicted, you can’t even image not paddling for any length of time. Several people have asked me why I dress in a drysuit and wear a PFD, gloves and a hat while paddling when I swim in the same lake – and sometimes on the same day – wearing only a bathing suit.

The dangers of cold water

Even though I enjoy cold water swimming a lot, cold water still presents some dangers. The first one is the cold water shock response. This is especially critical when you jump or fall into cold water without a wetsuit or drysuit. Cold receptors in the skin are activated, which leads to gasping and rapid breathing. The heart rate and blood pressure also increase. If you involuntary inhale water during the gasping phase, you can drown. One or two inhales can already have fatal consequences. Heart attacks and strokes are other risks during this phase, especially if you have some known or unknown cardiovascular conditions.

It is possible to reduce the cold water shock response by going into cold water regularly or by taking frequent cold showers. Still, rapidly entering cold waters has its dangers and that’s why I wait in the water for my breathing to become slow and controlled before I start swimming. When paddling, wearing a wetsuit and a PFD as well as gloves protects me from cold water shock if I were to fall in.

Autonomic Conflict explained

The second danger results from a phenomenon called autonomic conflict. It can happen when your body and your face are immersed in cold water. While your body feels stressed from the sudden cold sensation, it sends the message to the heart to increase the heart rate.
At the same time, receptors in your face that are involved in the human diving response tell your heart to slow down to conserve oxygen. When both signals arrive at the heart at the same time, the heart can get confused – and may stop, which leads to drowning. That’s why I prefer a slow, controlled entry into the water when swimming and also like to wear a PFD when paddling that can help keep my face above the waterline.

Cold Incapacitation

The third danger is cold incapacitation. It’s more of a risk for swimmers, since cold water cools the body much faster than cold air. But if you get too cold – while paddling or after falling into the water – your body draws blood away from your arms and legs toward your core to protect vital organs. Your strength and coordination suffer and if you have to paddle back to shore against the wind in choppy conditions, this can get you into trouble. These are some of the reasons for dressing in a dry- or wetsuit, a PFD and other protective gear, even if you are used to the cold water. When dressed appropriately, you can relax and really enjoy paddling in the winter. Have fun and stay warm.