Michael Phelps' purple blotches spotlight 'cupping' trend

It wasn't just Michael Phelps' big win on Sunday that had people talking about the US swimming star. It was also the dark purple circles on his shoulders. Phelps, who won the 19th Olympic gold medal of his career on Sunday and helped the US men's team to victory in the 4x100 meters freestyle relay, is one of a number of Olympic athletes practicing "cupping," an ancient Chinese healing practice.

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Michael Phelps' purple blotches spotlight 'cupping' trend https://t.co/Y7wXqj3ulw pic.twitter.com/yYQ0AJ5L7S

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