(This version of the story corrects owner of Olive Young chain to CJ Corp in paragraph 5) By Hooyeon Kim SEOUL (Reuters) – Looks no longer center only on the face in beauty-obsessed South Korea, where more women are hitting the gym to improve muscle tone and physical health. As the ideal of beauty evolves in a country that is a trend setter in cosmetics and the pursuit of plastic surgery, women’s fitness has become a growth business, say purveyors of health products, from diet supplements to dumb-bells. Now they exercise,” said celebrity trainer Ray Yang, who leads a workout session during the Body Show, a weekly television event targeted at women that is now in its second season.