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Mystery #1Tier 2water / pressure / body

Why do your ears start to ache when you swim down to the bottom of a deep pool?

Dive down to touch the floor of a deep swimming pool and, about halfway, your ears start to ache and go funny. It never happens while you paddle at the top. The deeper you kick, the worse it gets. What is down there, squeezing your ears?

A swimmer in a diving mask walking along the bottom of a deep pool, well below the surface.
Photo: U.S. Navy / MC3 Diana Quinlan · Public domain · via Wikimedia Commons

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