His other daughter, Isabellah, 9, recently returned from the nationals with a bronze medal.
Sensei Rangi Smith, who founded the Bay of Plenty Karate Association, says his club has had more girls in the last two years than in the past 20.
''I think it's great. We have about a dozen girls currently.''
Sensei Paul Scott, of Kiaido Ryu Martial Arts in Katikati, says the number of female members has doubled in the past four years.
''The sport has changed. It was more boys then girls. Now the majority of our juniors are female. I think girls [nowadays] are more confident,'' he says.
''They're good martial artists. They seem to learn faster.''
Sifu Grant Buchanan, of Mile High Karate, says martial arts has more to offer girls now.
''We have a lot of girls training with us and, in some classes, there are more girls than boys. Twenty years ago, it was very much the guy standing in the front of the school hall yelling and screaming. Now there are more professional studios. More and more it is seen as being a great place to boost self esteem for girls,'' says Buchanan, who has four daughters, all of whom have done karate.
It's self-esteem - in girls and boys - that is the golden nugget in the sport.
More parents are turning to martial arts as a way to combat bullying, but not through physical fighting.
''It's about recognising the signs, situational awareness. Knowing not to stand and take it, that they can walk away,'' says McGregor.
''We focus on self-respect. Fighting is the last option.''
Parents want their children to be able to look after themselves, says Smith.
''The objective is not to have any confrontations with anyone, to recognise situations before you get into physical contact. Self confidence, well-being and self esteem is part of that. That is what we call the 'spiritual' side - the self-awareness and mind control.''
Scott says it's a fun way to get fit, with the added benefit of learning self-defence skills and confidence.
''I like to think of it as a way of life - to live healthily, body and mind, and build good moral fibre. It's really cool to see their attention change. They come in a bit cocky, cheeky and lacking respect and they gain respect and self discipline.''
Buchanan says the most important aspect of martial arts is character development.
His karate students are required to do tasks at home and put in a good effort at school. School reports are kept on file and there are areas at the studio in which they can do their homework.
With regards to bullying, if you have confident kids, bullies are not interested, says Buchanan.
''It goes a long way towards the bully not being able to make an impression. My trained kids will put up with a lot because it doesn't really matter to them. That's one of the subtleties of bullying that people often miss. If it doesn't worry or affect you, it ceases to be bullying.''
Garry Carpenter, of Western Bay Olympic Taekwondo, however, says he will turn away any parent who wants to enrol their child to help them physically fight off bullies.
''Martial arts is not an antibullying device. Martial arts is something that gives you confidence. Confidence can get you out of a bullying situation,'' Carpenter says.
''My personal view is that bullies are predators. Predators look for easy prey. The more confident you are the less likely you are to be preyed upon.''
