Abi Oyepitan is used to outsprinting her rivals during her days as an Olympic athlete.
But when her 11-second time goes out to over 11 months, and the 100m sprint stretches out to 40,000 nautical miles, then they are more than just rivals.
"They're demons, mental demons," Oyepitan told AAP.
The Commonwealth gold medallist arrived in Sydney last week halfway through a gruelling fourth leg of the Clipper Round the World race that kicked off in London on August 30.
Oyepitan joined the crew of GREAT Britain in Albany at the start of the December, where the fleet of 12 boats plunged below the 44th parallel before moving across the southern seaboard.
"Mentally it was challenging because it was lovely and nice from Albany and all of a sudden you hit the Southern Ocean and it was non-stop waves coming over and you were heeling over," the Londoner said.
"Speaking to some of my crew members who are seasoned sailors, they said it's one of the hardest legs you could do as an amateur."
For two weeks, the 35-year-old was locked in the snakepit, pulling, trimming and grinding away at the sails where she admitted hitting a mental wall.
"I'm a sprinter, so this is the ultimate endurance. It's not even a marathon," said Oyepitan, who was forced into track and field retirement last year due to injury.
"The concentration you have to have, you've got to be on it because anything can happen. As a sprinter, you have two hours to recover and then you're okay. Here it's non-stop."
Next up is four days of hard sailing south aboard GREAT Britain in the Sydney to Hobart race, which will act as a sprint compared to her previous fortnight being bashed by the winds in the Great Australian Bight.
Oyepitan, who contested the 200m final at the 2004 Athens Olympics, said she was excited to participate in one of the most renowned events on the sailing calendar.
"Another one of the reasons why I joined this was because, for me, that's where it really becomes a competition," she said.
"It's short, like a sprint, and you can see all the other boats. Usually I'm in a straight line and can see all my opponents. It's the most amazingly prestigious boat race ever."
