Double Olympic medalist Natsumi Hoshi, who won the bronze in the women's 200-meter butterfly at the 2012 London Games and the Rio Olympics in August, said Tuesday she is retiring from competition.
"The biggest (reason for retirement) is that I gave my all at the Rio Olympics," Hoshi told a news conference in Tokyo. "I watched my race a number of times, but I didn't get the feeling of frustration like before. I gave everything I had and am satisfied."
The 26-year-old appeared in three consecutive Summer Games and as many world swimming championships despite suffering from Graves' disease, characterized by excessive production of the thyroid hormone, for which she had the thyroid gland surgically removed in November 2014.
Last year, she became the first Japanese woman to win a gold medal at the swimming worlds.
"I've had to deal with illness and surgery, but because I went through these things, I was able to genuinely think that I love to swim and that I want to return to the pool again," she said. "A lot has happened, but to sum it up, I led a happy competitive career."
Hoshi will remain with the swim team of sporting goods maker Mizuno Corp. as an assistant coach.