Cupping therapy wins gold in the eyes of Olympic athletes

Olympic athletes have been spotted in Rio. No really, athletes have been spotted with red circular bruises as a result of cupping therapy.

Cupping is an ancient therapy used to promote blood flow and healing. Round glass suction cups are warmed then placed on sore areas of the body. This creates a vacuum, which relieves pain while stimulating muscles and blood flow. The marks left behind typically fade after a few days.

Michael Phelps was seen undergoing cupping therapy in an Under Armour commercial earlier this year. The marks could be seen on his body during swimming events in Rio.

Some doubt the benefits of cupping therapy -- but it's taking home the gold in the eyes of the Olympians.

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