From couch potato to fitness junkie
Three years ago, Angus Petrie weighed 120kg and lived a mostly sedentary lifestyle.
Fast-forward to today, and the 34-year-old is 50kg lighter and competing in a 24-hour mountain-bike endurance race.
"It does sound a little bit crazy," Petrie said.
"My life is just completely different and I feel so much better. I'm a fraction of the person I once was."
Petrie, a transport manager, decided to change his lifestyle three years ago after his marriage ended.
"My sister sent me a bike down from the North Island and said get your fat bum on that bike. I did and I caught the fitness bug."
He gradually built up his fitness to the point where he was competing in endurance races, including the Coast to Coast.
"I have gone from a 120kg couch-dweller to a 70kg fitness nut. I train every minute I can and get itchy feet if I don't get out on my bikes, pound a track with my feet, or feel the water under me in my kayak."
He has previously done 10 and 12-hour endurance rides in the South Island, coming third each time.
"I discovered my real love is for endurance mountain biking and decided a 24-hour endurance race would be a whole heap of fun."
Petrie decided to do the World 24-hour Solo Championships in Australia this October, but wanted to do a New Zealand race as a "lead-up".
After finding a lack of 24-hour races in the South Island, he decided to organise his own at Bottle Lake Forest.
"We built this unofficial race and I organised some of my friends, who are experienced racers, to do it with me. There's nine of us doing it now."
The event starts at 10am today and runs until 10am tomorrow.
"We've got a 12km course that's going to take us about 40 minutes to do a lap. There will be a pit stop at every lap so you can get more food and drink," Petrie said.
At the end of the race, whoever had done the most laps, or "whoever was left standing", would be the winner.
"You can stop as many times as you like but I hope to spend at least 23 of the 24 hours on my bike."
Although his friends were experienced racers, Petrie said he hoped to be the winner on the day.
His partner, Leigh-Ann, and his bike mechanic would be his support crew. The hardest part would be keeping hydrated and fed for the entire race.
"We might burn 400 calories a lap, so we'll probably burn 14,000 calories for the whole event. We're going to have to be eating pretty much constantly. If you get to the point when you're hungry then it's too late."
There would also be a "whole lot of mind over matter" to keep his body going.
Petrie hopes that if the race is a success it may become a yearly event in Christchurch.