"It was so hot. We were in the red zone, which was one zone away from cancelling the event.
"I just had to keep pushing myself, saying, 'You are at the world champs and you've only got this one moment so just push through the pain, it'll all be worth it'."
While the mental notes-to-self certainly helped on the day, a lot of her success came down to hard work leading up to the event, both physically and mentally.
For the past three years, Goodisson has been part of the Woodford House Sports Academy, where she learnt to set goals and mentally prepare for the international event.
"Standing on the podium, I couldn't really believe I had won gold because I had no expectations going into the event. But it felt well-deserving because I had put in a lot of effort."
Woodford House director of sport Chris McIvor said her achievements are remarkable for someone who has only been competing in triathlons for one year: "Eva has always been a star athlete, particularly in swimming, but to become a world champion in aquathon is a testament to her commitment and positive attitude."
Goodisson's coach, Ken Maclaren, said she performed at the top of her game.
"I knew she was in great shape but putting together a good performance in a top competition can be very different from racing well in low-key events at home. She clearly came through with flying colours," MacLaren said.
Chloe Johnson is the Woodford communications and development manager.