She was about 50 when she completed her first marathon after enjoying and doing well in shorter events in the lead-up. Since then she has continued to complete at least one marathon a year.
"My first event was a 10km and I realised ... I did really well," Mannington said.
She hopes to inspire others her age to take up walking or running events as a way to keep fit and active.
And her words match her actions. She runs the Body+Soul fitness classes of low impact aerobics, strength and balance as well as social events for over 50s as a way to encourage them to exercise.
"Hopefully I can really motivate and inspire others at my age and a bit older ... to me it's not all about me."
She runs about four classes a week and says it helps with her own training, particularly the stretching.
Mannington has always kept herself fit and has come from a family who have always encouraged her in her sporting achievements, especially her late dad Leslie Stewart.
"I do come from a family who have been into fitness and my dad ... he used to encourage me very much when he was here," Mannington said.
"He always wished me all the best, always wanted to know how I got on."
It's no wonder she has achieved so much.
Mannington has earned more top age-group placings in her marathon and half marathon career than she can keep count. She has also competed in the New Zealand Masters Games as a competitive walker, earning medals at every one over the years - most of them gold.
"I'm not really a fast runner, but I'm a fast walker."
Tonight, Mannington is looking forward to another We Run the Night event. Still dealing with a long-time, upper hamstring injury, she said she works hard to make sure she remains able.
"I'm just thrilled that I can do it."
Mannington said she does "as much training as time allows" but will often do about 70km over a week in her busiest times. And she has no plans to stop any time soon.
"I'll keep going and see how long I can do it. There are people out there in their 80s who are still doing marathons."
