Recovery is key to swimming when it’s cold
The best way to prepare is to “swim down the temperatures” throughout autumn. But you can acclimatise at any point; start with just one minute twice a week and build up. You can also prepare your body with very cold, short showers.
Plan your swim carefully. Always go with someone else, who stays on land. Agree how long you’re going to be in the water, and how you will get in and out. When you get in, aim to be immersed within three minutes, or you will just get too cold. Splash water on your chest (if you’re not in a wetsuit) and face. Always get out of the water at the agreed time – or sooner. The person swimming is not the best judge of when it’s time to get out (the cold can make you confused).