Swimming in 4c water! Can I?

I spotted these brave women today going for a swim in 4c water with only wetsuit gloves and shoes! They swim for about 10 minutes most mornings. I wonder if I could do that, I have a strong allergic reaction to cold water LOL.

I want to be able to swim in freezing water!!! For now I have set myself the challenge to take a New Year's Day plunge as part of #theyeariturn65, as I expect it make my soul sing.