There are very good reasons runners in today's Rotorua Marathon will be trailed by coloured balloons.
The balloons indicate that runner is a pacer - the different colours of the balloons indicating the time they are planning on finishing the race.
Rotorua's Sue Crowley is one of the pacers; her balloons will be purple and her task is to finish in 3h 45m.
"The theory is, if you can do it properly, people can pace off you - especially first timers," she said. "When I did my first couple of marathons, it was a big help to have people around that you can see that are at a set time, especially at the beginning because you always worry at the beginning that you are going too slow."
It will be a new experience.
"I've never done it before, but it's quite a challenge. I've been out on the course quite a bit trying to work out the pace," she said.
"You have to have a plan before you start and you've got to try and do it so that if anyone is with you, you don't kill them. You want to get them round at the right time."
She said the trick was to run at a constant pace - not always easy on the undulating Rotorua course.
"All the pacers are volunteers and it's quite an undertaking really because you want to get it right for people, especially if it's their first marathon. You want to keep it constant, so you don't wreck anyone's race, so that's the real trick with the hills of course.
"I've been out there mapping it out. I think I've got the pace sorted - I've got it written all over my arms."
Crowley said it was a new experience to tackle a marathon having put in so much preparation.
"Normally I just go, and see if I can keep going."
Crowley completed the Tarawera Ultramarathon in February and said then that she had never quite managed to compete the Rotorua marathon in a time she was happy with. However, she decided this was not the year to try and do that.
"Because I wasn't going to compete in it, I thought 'I need to go and help because it's the big Rotorua event. I couldn't really see myself standing on a corner clapping somewhere, or marshalling, and then I was looking, because the Auckland club organise the pacers because they are a bigger club, and they were missing the 3h 45m [pacer] and I thought, I could do that'."
The half marathon starts at 8am today with the marathon runners setting off at 8.20am.