Why do people feel cold after a swim?

Answer 1

Theres a few reasons for that. First, once you stop swimming, your body temperature will start to decrease because you aren't exerting anymore energy. Secondly, you're wet, so it is easier to feel cold, especially if there is wind. Thirdly, the pool water was probably cooler than your body temperature so it would cool you.

Answer 2

After a swim the swimmer is covered with water, and water evaporates, which has a cooling effect.