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In fact, the Caversham athlete is better at it than anyone else in the country.
The 38-year-old has returned from the weekend’s national 24-hour running championships in Auckland with a gold medal.
Glennie ran further than any other New Zealander in the senior men’s grade to take the national title.
Running for 24 hours in itself may seem like a big enough challenge.
Doing it for 184.451km, or 461 laps, around the same 400m track adds a whole different dimension to it.
"You get sick of it pretty quickly, but it’s like ‘oh, hey, I’m only doing it for a day’," Glennie, a mental health support worker, said.
"I wouldn’t just go out and do a really long track session like that for the sake of doing it.
"But definitely after a minute or two after I started I was like, ‘I can’t wait for this to be finished’."
He was thrilled with the win and very surprised, having entered thinking he may have an outside chance of a placing.
However, he finished 4km ahead of second-placed Bryan McCorkindale, who had led by 20km early on, but slowed down after picking up an injury.
Glennie took the strategy of running three laps and then walking one, before walking the last few hours after realising he had a big enough gap to win.
The win was his first national title, but goes with a placing of second at the national 100km road championships.
An ultra-marathon runner, he does a lot of 100-mile (160km) races and was aiming to complete the unofficial "ultra-slam" in a few weeks’ time. He has run the 100 mile races at Northburn and Naseby, as well as completing at least 100 miles at the 24-hour championships.
All that remained was to complete the 100-mile Round the Mountain race in Taranaki next month. He would become just the third person, after Croydon Paton and Lance Hunniford, to complete all four races in a calendar year.
To make it even more impressive, Glennie only began running in 2014, having progressed from doing the Dunedin half-marathon that year.It was something he found he enjoyed and gradually increased his distance as he looked to take on new challenges.
He usually ran for an hour a day during the week and aimed for a longer run of up to eight hours in the weekends.
Despite all that, he is still wondering the same thing as everyone else: what would compel you to want to run for 24 hours?
"I’ve been asking that myself as well.
"You run ultras and that and people ask you that all the time and I still haven’t nailed down an answer.
"It’s probably got something to do with just trying to find my limits, trying to prove myself and liking a challenge, and it gives me focus.
"That’s probably the big thing. It just gives me focus."