Those dark red, spots dotting Olympians’ shoulders and backs are not cigar burns. They’re not perfectly circular hickeys either. Viewers watching the Olympics this weekend may have spotted the pepperoni-like bruises on athletes and wondered: What is that? Olympians at Rio have taken to cupping — an ancient therapy that have mostly been used in Middle Eastern and Asian countries, especially China. The therapy consists of having round glass suction cups that are warmed, then placed on sore parts of the body. The placement of the glass cup creates a partial vacuum, which is believed to stimulate muscles and blood...