Australian Bridget Quayle suffers from mental health problems and wants to break the cycle in her family.
The 39-year-old from Canberra, who is a mother of two young boys and works part-time for the Australian Government, hopes to achieve a special goal of completing the 26km of the Tussock Traverse.
"Women in my family have inherited mental health issues which I would like to prevent," said Quayle. "Of course, I want to break the cycle."
She took up trail running 18 months ago to help with her mental health and it has been a rewarding journey.
"Any exercise is good for mental health but running is extra calming for me," she said. "I am free to think about anything I want while running. The fresh air and the freedom make running a great escape as well as the endorphins afterwards."
She has simple advice for other people who have mental health issues.
"Exercise, get into running, eat well and generally look after yourself. Positive psychology and gratefulness help."
Quayle ran her first 10km at the Australian Running Festival in April 2012 and she did her first half marathon a year later.
She is using the run in the Tongariro National Park to prepare for her first marathon in April.
"My mid-life crisis marathon, I like to call it ... I wish it was only 40km as that would be more fitting."
It is also fitting that Quayle will have her family with her as she looks to complete the tough trail run.
"My mum is coming with me as she knows how much doing this event means to me. My mum also has bipolar, so we are taking a risk with her coming but mental health shouldn't hold people back."
It is that sort of attitude that has seen Quayle not make excuses and hit the trails with real vigour.
Before she started running she went to the gym only twice a week. Now it is four runs a week.
The finish line of the Tussock Traverse is going to be an emotional place for Quayle and her family.
"I hope my mum is organised enough to have my kids there waiting for me," she said. "I love the looks of pride on their faces when they see me finish."