Middle-distance swimmer Kosuke Hagino, who won the 2016 Rio de Janeiro Olympics' men's 400-meter individual medley, announced his retirement on Sunday.The 27-year-old Hagino won bronze in the same race at the 2012 London Games as a high school senior. He also won the 200 IM silver and a bronze in the 4x200 freestyle relay in Rio but failed to reach a podium this summer in Tokyo."I'd decided that my last race would be at the Tokyo Olympics," Hagino told a Tokyo press conference. "I'm amazingly happy and have no regrets. When it came to bringing it to an end, I had a strong inner resolve."Hag…READ FULL ARTICLE