Maree Connor finishes 7th overall in Badwater ultramarathon in California's Death Valley, one of the hottest places on Earth

In a phenomenal effort, the 43-year old finished seventh among 100 male and female runners in the gruelling 217-kilometre event in California's Death Valley, one of the hottest places on Earth.

It completed a remarkable journey for the Calvary Mater emergency department nurse unit manager, who had spinal surgery for chronic back pain five years ago.

Mrs Connor was due to return to Newcastle on Monday.

Speaking from Los Angeles International Airport ahead of her trip home, she said "the race was an amazing adventure".

The mother of two girls, aged seven and nine, secured a podium place as the third woman across the finishing line.

She finished in 27 hours and 49 minutes, the ninth fastest female time in Badwater's 46-year history.

Mrs Connor was only the seventh Australian woman to be invited to compete in the event, which was described as the "world's toughest foot race".

"It was 47 degrees on the start line at 10pm. Within two hours it was up to 59 degrees," she said.

"While running you have the feeling of a hot hair dryer blowing on your face.

"Or, imagine opening the oven door at 220 degrees and standing in front of it for hours."

Her crew sprayed her with water often and "dunked my hat in an ice bucket".

"It was dry within minutes," she said.

"They were handing me flasks of iced water that would heat in my hand and were hard to drink after about 20 minutes - like drinking boiling water."

The heat took its toll on her shoes.

"My shoes held up, but look like they melted a bit on the hot road. When I could, I ran along the white line."

She said the race "starts in waves to separate the crew cars a little".

"I was in the third and final wave, two hours behind the first starters."

The race starts below sea level in the Badwater basin and heads north towards the aptly named "Furnace Creek".

It crosses two big ranges and drops down onto the desert floor in between. The "final push" is a half marathon and 1500m elevation.

Mrs Connor handpicked her crew for the event.

They each had individual tasks to ensure all bases were covered.

"The team only met each other one week before the race," she said.

"Without a crew you cannot achieve anything like this. They were amazing and like clockwork."

On the race's final climb, she alternated her crew to walk a mile each with her.

"We talked and reminisced about the day we'd had. This was my favourite part - enjoying their company individually after what they had done for me all day and night," she said.

Mrs Connor had spinal surgery five years ago due to chronic back pain from a work injury.

"Before that, I struggled with even picking up my baby," she said.

"After surgery I vowed that, if able, I would use my body to the best of its ability and never take it for granted.

"I did this race to see how far I can push myself, both mentally and physically. Turns out I can push it a lot."

By the 150-kilometre mark, she was in 13th position overall and fourth in the female ranks.

"This is where I started to push. I was patient and careful, but also brave."

Before the race, she had trouble with jet lag and trying to adjust her body-clock.

"The team and I all struggled with getting more than about four hours' sleep each day and that all added up.

"Towards the last three hours of the race, I was really struggling to stay awake. I was drinking cold brew coffee and coke and nothing else."

Nevertheless, she said her body was feeling "great".

"It's been nearly three days since I finished and the legs are almost back to good," she said.

"They have been a little heavy. I did lose a few toenails, but that's not abnormal for me."

She burned a lot of calories during the race.

"I've just been eating all the food I can get my hands on. The heat meant my heart rate was a lot higher during the race than it normally would have been, so I used a lot more nutrition and fuel."

Despite the epic nature of the event and long trip home, she won't take a break.

"I'll be back running next week sometime I'm sure."