At the age of 13 years 267 days, she made history by winning the first-ever Olympic gold medal in women's street skateboarding. With Brazil’s Rayssa Leal second and Japan's Funa Nakayama third, the average age of the podium was 14 years 191 days, the youngest in Olympic history. A 4.66-point bigspin to frontside boardslide put Nishiya into the lead, while her final backslide boardslide delivered her the gold. She became the second youngest Olympic champion, behind diver American Marjorie Gestring in 1936 who was 63 days younger. She is the youngest athlete to win an Olympic gold medal for Japan. Also, in 2021, she won a silver medal in the women’s street world championships.