A broken ankle could not stop a 56-year-old from completing a 42km marathon - though it took her nine hours amid increasing pain.

Running the Motatapu Marathon, Di Howarth, of Cromwell, thought she had twisted her ankle after 3km, yet decided to carry on.

"I fell right down on it, but I didn't hear it cracking," she said.

She hobbled to the first of the aid stations, where it was strapped, and she carried on.

"All I could visualise was the finish line - you visualise that when you're training. I really did want to cross that finish line."

A very tough nine hours later, Mrs Howarth crossed the finish line.

"The further I got, the slower and sorer I got. There were two kilometres to go - they were the longest two kilometres ever."

Medical staff at the finish line took one look at her leg and sent her to Lakes District Hospital at Frankton, where she learned she had broken her tibia near her ankle.

"It wasn't straight. It was pretty ugly - very ugly."

Mrs Howarth and friend Leigh Buttar had spent months preparing for the marathon, getting up at 4.45am to train.

Mrs Howarth said there were dark moments during the 39km to the finish line with her friend.

The pair often asked each other whether they should continue.

Nurses at the hospital were surprised she had managed to run nearly 40 kilometres on a broken ankle. "It probably was a bit silly. But [on Saturday] it wasn't silly."

The pair had expected to complete the marathon in five-and-a-half hours.

They were the last to cross the finish line.

"But, hey, we did it. It was really quite emotional," Mrs Howarth said. Fairfax NZ

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