Ana Marcela Cunha, of Brazil, poses with her gold medal after winning the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo. (AP Photo/David Goldman)

Swimmers compete in the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo, Japan. (AP Photo/Jae C. Hong)

Ana Marcela Cunha, center, of Brazil, and Ashley Twichell, of the United States, compete during the women's marathon swimming competition at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo, Japan. (AP Photo/Jae C. Hong)

Ana Marcela Cunha, of Brazil, touches the timing board to win the women's marathon swimming competition at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo, Japan. (AP Photo/Jae C. Hong)

Sharon van Rouwendaal, of the Netherlands, kisses her silver medal during the victory ceremony for the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo. (AP Photo/David Goldman)

Haley Anderson, of the United States, jumps in the water at the start of the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo. (AP Photo/David Goldman)

Samantha Arevalo, center, of Ecuador, takes a drink at a feeding station during the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo, Japan. (AP Photo/Jae C. Hong)

Sharon van Rouwendaal, of the Netherlands, competes in the women's marathon swimming event at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo. (AP Photo/David Goldman)

Gold medalist Ana Marcela Cunha, center, of Brazil, is hugged by bronze medal winner Kareena Lee, right, of Australia, after the women's marathon swimming competition at the 2020 Summer Olympics, Wednesday, Aug. 4, 2021, in Tokyo, Japan. At left is Germany's Leonie Beck who placed fifth. (AP Photo/Jae C. Hong)