[6] In 2017, Miyahara repeated this result with the silver medal in the women's kumite 50 kg event at the World Games in Wrocław, Poland.

[8] At the 2018 Asian Karate Championships held in Amman, Jordan, Miyahara won the gold medal in the women's kumite 50 kg event.

[2] A few days later, she won the gold medal in the women's kumite 50 kg event at the 2018 World University Karate Championships held in Kobe, Japan.

[1] At the 2019 Asian Karate Championships held in Tashkent, Uzbekistan, Miyahara won the silver medal in the women's kumite 50 kg event.

[5] In November 2021, she won the gold medal in the women's 50 kg event at the World Karate Championships held in Dubai, United Arab Emirates.