Long distance elite runner Jeff Breese completed the 100km Ultra Trail through the Blue Mountains on the weekend.

The return to his Lake Albert home was marked by a distinct lack of discomfort, a fact that now seems odd in hindsight.

"I got up in the morning, and felt like I could go to work," the 55-year-old athlete said.

"I thought, 'I probably shouldn't overdo it', so I went back to bed. I woke up a few hours later in the ambulance."

Mr Breese had suffered a sudden seizure.

"[The paramedics] asked me, 'where do you live? What is your name?' and I gave them the answers," he said.

"They said 'You were in this run yesterday?' and I said, 'what run?' I just had no memory of it whatsoever. You'd think I'd remember running for 25 hours."

Only discharged at midday on Wednesday, Mr Breese was told his unexpected episode had been caused by an "imbalance in electrolytes".

Despite the time length of the run surpassing others he has attempted, Mr Breese would still consider the Ultra Trail as one of his easier sporting journeys.

He is more accustomed to completing multi-disciplined events.

His specialty he has completed three times in Jindabyne.

It involves a 12-leg rotation through eight kilometres of swimming, 25 kilometres of running, 26 kilometres of paddling in a kayak, and an enormous 63 kilometres of mountain biking.

While most complete the journey in a team, Mr Breese typically undertakes it all by himself.

Last year, he even set the record for competitors aged over 50 when he completed the entire circuit in 11 hours and 54 minutes.

The Ultra Trail involved the steep ascent of more than 10,000 sharp steps.

So steep was the terrain that at one point, it required a stepladder to traverse.

"I did this one for the fun of it. It was a buzz," he said.

Mr Breese has been running long-distances since 1994. In those 25 years he has maintained his fitness and kept mindful about his limits.

The legacy of a dear friend has instilled the knowledge of his boundaries, at least, for the past few years.

"My good mate was training for an iron man in Port Macquarie. One day, he came home and felt a little sick, so he lay on the couch," he said.

"He had a heart attack and was in a coma for about a week."

He was a fit and healthy 56-year-old. Nevertheless he died later the same week.

"It's always made me think, I can't over do it. I've got to be careful."

Having now recovered from his health scare, Mr Breese is planning to lace up the running shoes once again.

It may be some time before he is ready to complete another ultra marathon, but he is far from leaving competition altogether.

A member of Wagga Road Runners, he is yet to decide whether he will join the team's bid for the annual City2Surf in August.

So far, 27 Wagga residents have registered for the even, with capacity for 40 to attend via the team's bus.