The pack will contest the North Face 100 - a 100 kilometre run in the Blue Mountains.

It's going to be as tough as it gets, but Simon Turnbull and the group believe they are in good shape to get over the line tomorrow.

Each member has been on plenty of training runs. Turnbull trains about three times per week, depending on his schedule.

An average run for the exercise physiologist is between 50 and 20km, and anything up to about 40km on weekends.

Fortunately, there are plenty of good running routes across Port Macquarie and the Hastings. Bago is one of Turnbull's favourite areas, and the group has also tackled North Brother Mountain to Lighthouse Beach run.

That course starts on the western side of the mountain, winds its way to the top and then to Port Macquarie.

"It's good smashing yourself a bit [up the mountain] before you even get to run," Turnbull said.

There are some big hills the area between Herons Creek and Comboyne.

"They're the hills you need [in training]," Turnbull said.

There's the expected friendly banter, but Turnbull said the group's focus was on encouragement.

He's got the advantage of having completed the race before. Last year, Turnbull finished the run in 16 hours, 30 minutes. He thinks anything under 20 hours is a good time.

Turnbull did the Cradle Mountain Run as preparation back in February. It's part of the extra training he's put in this year.

Turnbull began running with Port Macquarie's Tracks & Trails running group. He started out doing a 5km run once a week.

"Things got bigger," he said.

Pushing himself harder than he previously thought possible is part of the attraction.

"Ultra [running] is a bit special. It's quite meditative," Turnbull said. "It pushes you far beyond the limits of what you think you can do. When you're really stuffed and you think you can't go any further, you're usually only about halfway."