Charlie Butler and her great Kiwi Shape Up

"I have been overweight most of my life. After the birth of my third child six years ago I weighed 107kg. I had been trying to get to my goal weight of 59.9kgs for the anniversary of my father Tony Butler's death this month, but the weight just wasn't moving.
"Hearing about The Great Kiwi Shape Up gave me the motivation I needed. People around the country were given the challenge by More FM and Jenny Craig to lose 5kg in a healthy manner in eight weeks. I entered the competition three weeks late. I was 79kg but managed to lose 6.2kg in five weeks and four days.
"Dad lost his battle with cancer at the beginning of 2010. My weight-loss fight doesn't even come close to what Dad endured. I ran for him. I never gave up and I set my mind to the challenge. I was crowned the national winner on December 6 and won $10,000. I donated half of my winnings to help research a cure for cancer.
How I lost the weight
"I had tried to diet many times before but I think you have to be ready in yourself to do it. It's more a mental challenge than a physical one. When I used to exercise, my mind would tell me, 'You can't run any further, you've got to stop, you can't breathe'. But once I changed my thinking to only positive thoughts, it was amazing how fast I could finish my weights and cardio routine.
"My big weight-loss secret is high-intensity interval training. These short bursts of intense physical activity cause your body to burn fat hours after you've done it and it takes you half the time! You're burning fat while you're watching TV, while you're sleeping and who wouldn't want that?
"People who can't get to the gym can still do interval training at home. It even works if you're huge. You just walk to one power pole on the street, then go to the next pole faster, then repeat.
"Once you get fitter, you can run to the first power pole then sprint to the next. You get so much energy and you get super fit so fast.
"Your whole body changes - people noticed my bum getting smaller straight away."
Secret weapons
1. Carrot and zucchini sticks with salsa for when I was really hungry. You can munch down as many as you want.
2. Sugar-free chewing gum - great when I was out if I had the urge to grab a chocolate bar.
3. Rice cakes - for when hunger strikes at lunchtime and I'm eying up Burger King.
4. Baked beans - for meals in a rush.
Charlie's top tips
1. Find the fighter within yourself. Keep conquering. Once you see a small result, you won't want to stop.
2. Make tiny goals, because they are realistic and achievable.
3. If you can just get  5kg off, once you see that and you hear comments from people, that keeps you motivated and on-track.

4. Think of it as setting an example for your children. If you're feeding your kids right, why can't you feed yourself right? And who is going to look after them if you're not there?

5. If you don't feel like exercising, force yourself - because you will feel great.

6. Everything is a choice, from what you say and  do to what you put in your mouth. I try to make what I think are good choices ... and it feels good.