Why are Olympic swimmers bundled up like they're competing in the Winter Games?

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The U.S. Olympics swimming team has been racking up wins in the pool in Paris, with 20 medals won so far, including four golds.

And for the many watching the competition, a question of apparel has been top of mind. Google trends in the U.S. shows a big spike in searches for “why swimmers wear parkas.”

The question has also been circulating on social media.

"Why do swimmers wear coats before a competition?" asked the apparel company Dr. Warm in a TikTok video, before going on to answer the question in this way: "It is to keep the body temperature stable after warming up and optimize the competitive state."

So why is warmth important? Especially in the balmy Paris summer?

It helps keep an athlete's muscles loose and ready to go, a 2023 Swimming World Magazine article explains. If the muscles cool down, they become stiff and less responsive.

The parkas are also, of course, useful for bone rattling winter practices.

Apparel companies like Speedo make special water-resistant parkas for swimmers. Many are knee-length, lined with fleece and topped with big, floppy hoods. They also have pockets for goggles and other swim gear. Swimmers can wrap themselves in them straight from the pool and they're not cheap. They run about $100 - $200.