GKR Karate
I competed in the GKR Karate World Cup at Sydney Olympic Park in October 2005. There were 8 women in my division for kata (a sequence of stylised movements) and six in my division for kumite (sparring against an opponent).
My division was: yellow/orange belt; over 45; women. It's all non-contact at this level, which is good, because I don't believe in hitting people.

Belt colours in order from white to black, and the katas required for each belt, are described on the unofficial GKR website at GKR Grading Information.

And here are a couple of photos: Me with medals; Medals; Medal-winning kata; Gold medal presentation.