The 33-year-old general manager of Rutledge, from Tuggeranong, jokes about his chances at making it across the finish line, but he has no shortage of inspiration.

Having had aggressive treatment for non-Hodgkin lymphoma when he was a teenager, undergone several frustrating rounds of IVF treatments with his wife to bring their son into the world, and met countless cancer-affected families on the way, Mr Glover is determined to finish the 21.1 kilometres.

But before this week, he's never run more than seven kilometres.

"Originally, I was pretty excited about doing the half marathon but then I went for a run and that's when reality hit. I thought, 'What have I done?'," Mr Glover said.

"I was added to [a running festival Facebook group] and when I hit my first five kilometres, I was pretty proud of it. But then there were people putting up runs of 25 kilometres and 32 kilometres."

Mr Glover ran his first 12 kilometres on Tuesday and planned to get up to 16 kilometres before taking on the half marathon distance for the first time at The Canberra Times Australian Running Festival, presented by Tata Consultancy Services.

His training leading up to the event involved three runs a week - two five kilometre sets on a track or footpath, and one 10 to 12 kilometre one on a treadmill - but otherwise his routine would stay mostly the same.

"I'm just trying to increase the running and have no alcohol between now and when I finish," Mr Glover said.

"The thought of a beer at the end of it will get me through the last five kilometres."

Mr Glover is running in this year's event in memory of Annabelle Potts, the five-year-old girl who inspired a huge fundraising effort across the national capital.

Money raised by Mr Glover's team, in association with Rare Cancers Australia, would go to researching the rare brainstem tumour diffuse intrinsic pontine glioma (DIPG), which Annabelle died from, and other rare cancers.

"One of our suppliers said they were willing to sponsor a team and donate $3000 on the proviso that I ran the 21 kilometres," Mr Glover said.

Mr Glover has long been involved in Samuel Johnson's charity Love Your Sister which raises money for cancer.  He met Annabelle Potts' mother in April 2018 and hosted a gala dinner to raise more than $50,000.

"What's really opened up my eyes is that ... as part of being involved in this DIPG group there's other families out there with little kids the same age as Annabelle that are losing their battles with this cancer," Mr Glover said.

"The fundraising is really important and the money raised in memory of Annabelle will go directly to DIPG research."