Emma Mckeon, of Australia, puts on her gold medal during a victory ceremony for the women's 50-meter freestyle final at the 2020 Summer Olympics, Sunday, Aug. 1, 2021, in Tokyo, Japan. (AP Photo/Jae C. Hong)

Emma Mckeon, of Australia, poses after winning the gold medal in the women's 50-meter freestyle final at the 2020 Summer Olympics, Sunday, Aug. 1, 2021, in Tokyo, Japan. (AP Photo/Gregory Bull)

Emma Mckeon, of Australia, starts in the women's 50-meter freestyle final at the 2020 Summer Olympics, Sunday, Aug. 1, 2021, in Tokyo, Japan. (AP Photo/Gregory Bull)

Emma Mckeon, right, of Australia, and Sarah Sjoestroem, of Sweden, smile as they look at the results after competing in the women's 50-meter freestyle final at the 2020 Summer Olympics, Sunday, Aug. 1, 2021, in Tokyo, Japan. Mckeon won gold and Sjoestroem took silver. (AP Photo/Jae C. Hong)

Emma Mckeon, of Australia, dives off the starting block in the women's 50-meter freestyle final at the 2020 Summer Olympics, Sunday, Aug. 1, 2021, in Tokyo, Japan. (AP Photo/David Goldman)