Mariko Yamamoto - NHK Documentary
This video is getting a little old now but someone has done a pretty good job of subtitling it in English.
Her story is interesting because these kind of profile docos of elite women kenshi are not so common.
In spite of being very quiet and shy, she obviously has amazing determination to win. It also helps that she was a member of the Osaka Police Force Special Training Squad and trained 5 hours a day 5 days a week. Having a dad who is a previous All Japan champion doesn't hurt either!
Here she is teaching a Kendo seminar in Japan.
Also, an interesting research article in English on Japanese women's elite Kendo can be found here (download PDF) .