Morgan Coull took part in the World's Toughest Race

Even for the world's most adventurous and ambitious ultra-athletes, the prospect of completing an 11 day marathon covering more than 670 kilometres of sheer mountains, river rapids and dense jungle is a daunting one.

For Murray Bridge paramedic Morgan Coull, competing in the 'World's Toughest Race' was an opportunity to push his body - and his willpower - to the absolute extreme.

The 'World's Toughest Race: Eco-Challenge Fiji' pitted 66 teams of adventure athletes against each other in an 11-day expedition across some of the toughest and most unforgiving terrain in the globe - and every step of the way was recorded for a 10 part TV series.

With more than a decade of experience adventure racing under his belt, Coull was approached by a Victorian-based team who he had competed against in the past.

"They were looking for a fourth team member and .. it didn't take long to get my arm twisted," Coull said.

The race, which is now available to stream on Amazon Prime, was completed in September last year and tested competitors in various terrains including ocean paddling, sailing, outrigger canoes, mountain biking, jungle trekking and highland trekking.

Despite the constant fatigue, hunger and thirst that beset Coull, he said a particular highlight was an extensive rope climb over the top of the Navua Falls they completed in the dark of night and while being pummelled by rain.

This highlight however would be followed by one of the most harrowing sections.

"We had to do an eight kilometre swim once we were above the waterfalls," Coull explained.

"The water temperature was 11 degrees and a lot of people broke on that section from hypothermia and the really slippery rocks that you are trying to navigate either by swimming or slipping over rocks.

"There were some moments there that I didn't think I was going to pull through.

"It took a fair amount of resolve to just keep pushing forward and trying to keep moving because if you stop you die, basically.

The premier of the Eco Challenge race brings back the format after a 18 year hiatus.

Coull's team - Team Aussie Rescue - was comprised of a paramedic, a firefighter, special ops, and a social impact entrepreneur and Coull said their main goal going into the event was to complete the race.

"We went in to it knowing that only 10 teams finished it last time (2002) we were adamant that we wanted to finish."

"But just when you think its gonna be a couple of easy miles it could be some of the hardest longest miles of your life."

"We did a pretty strenuous bike-hike section that involved literally carrying bikes through mud for probably six hours because the mud was so thick that it was un-rideable and this was up a really steep mountain - so that was relentless."

OUTREACH: Coull is also the event director of Murrayland Multisports, a community organisation which hosts a range of adventurous challenges such as the Federation Ultra-Trail.

OUTREACH: Coull is also the event director of Murrayland Multisports, a community organisation which hosts a range of adventurous challenges such as the Federation Ultra-Trail.

Having competed at an elite level in short distance sprinting as a teenager, Coull said he had started extend his distances as he got older and eventually competed in his first multi-day expedition race in Tasmania in 2011 and was "hooked from there".

"The adventure racing is just a good place to hit a bit of an internal reset button and just get out amongst environment and nature and moving back to basics," he said.

"I don't know what it is that makes us want to get out there and punish ourselves and see how much we can suffer but you do get to see some pretty uncharted territories."

Living locally in Murray Bridge, Coull said he has been able to use the local conservation parks, trails, and gravel back roads a training grounds.

He is also the event director of Murrayland Multisports, a community organisation which hosts a range of adventurous challenges throughout the year and is designed - not just for elite athletes - but for anyone who wants to challenge, visit www.mmievents.com.au.

The 'World's Toughest Race: Eco-Challenge Fiji' is now available for stream through Amazon Prime.