Unlike most sports, swimming makes you hungry.

Usually, exercising triggers the release of hormones that suppress appetites. Not so with swimming. There is no universally agreed upon reason for this exception. However, it’s possible that the cold water can hold back the release of these hormones by lowering a person’s body temperature. Studies have shown that people who swim in colder water consume 44% more calories after their workout than people who swam in warm water.
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