When runners in the Chubb Bermuda Triangle Challenge marathon start to feel the burn on Sunday they could do worse than heed the advice of one of America’s greatest marathon runners, Deena Kastor.

Kastor, who won the Chicago Marathon in 2005, the London Marathon in 2006 and finished third in the 2004 Olympic Marathon in Athens, is giving the keynote speech to Triangle Challenge athletes at a pasta dinner held less than 24 hours before hundreds of runners push themselves to the limit around the island’s streets.

The inspirational 50-year-old is a proponent of positivity and believes that the mental side of marathon running is crucial to assist performance.

“I would venture to say the mental side is more important,” said Kastor, whose book Let Your Mind Run: A Memoir Of Thinking Your Way To Victory dispels the myth that positive psychology is a magical concept.

“They say that the mental breaking point comes at mile 20 but sometimes it comes a lot sooner than that. When it starts to hurt it’s almost masochistic but I think this is the moment I’ve been waiting for and it’s time to start thinking about my character.

“Sometimes you will be in the middle of a race and start to back-pedal on your goals or think you’ll look at the scenery today, don’t have to run a personal best and think nobody really cares if I’m first or fail to finish.

“As soon as I start thinking in these terms I realise it’s time make this about character. Instead of giving up I’m going to dig down. Instead of throwing in the towel I’m going to drop the hammer. I use any cheesy line in my head to get me looking forward to the next step or next mile.

“You need to do anything you can to talk yourself back into it rather than talk yourself out of it. I think often we can give up before it’s time but in your head you need to be your own cheerleader.”

At one time or other Kastor has held every American national record from 5K to the marathon, but she is adamant that goals must be constantly reviewed and changed to enable peak performance.

“Whatever the goal is to get you out there is the most important thing in the world,” Kastor said.

For me sometimes it was time-motivated and others it was just about winning. In 2005 when I was entered in the Chicago Marathon, I already had an Olympic medal and the national record but I had yet to win a race, so I wanted to experience what that felt like and that became my sole mission.

“It almost went horribly wrong. I had a minute lead over Constantina Dita, of Romania, and it came down to three seconds, so if the race was any longer she would have beaten me to that line.

“Whatever gets you outside to put in the work is what’s important and it should change as goals can get stale if we pursue the same thing all the time.

“When I broke the national record, it’s important in the accomplishment and pride that you did the work. That moment was special but for the 19 years I held the record it didn’t really matter. It only mattered when I was chasing Joan Benoit Samuelsen’s record, or trying to lower my own record.

“When I crossed the finish line third in London [2003] I was behind Paula Radcliffe, of Great Britain, and Catherine Ndereba, of Kenya. Paula broke the world record that day and Catherine lowered the national record so it was a really good day to run fast.

“But the juxtaposition was the elation of reaching that ultimate goal and the possibility of being able to run faster. The goal of the record was completed but the women in front of me showed me there was more to accomplish and fired me up for what’s next.

With a stellar career including Olympic medals, historic marathon success and honours galore, including winning the 2003 Jesse Owens Award as the top female track and field athlete in the US, it might be difficult for Kastor to nominate her proudest racing moment but her choice comes quickly and is something of a surprise.

“In 2015 I ran the Chicago Marathon and broke the American masters record and was a second shy of the world record,” Kastor said.

“That was a culmination of everything I had and the accumulation of every lesson I learnt in the sport and my build-up was terrible.

“I got the flu, I had terrible allergies and we had a big fire season in California so the build-up was interrupted and I remember telling my husband, who was my coach at the time, that I was done and I couldn’t handle any more challenges.

“He told me it was strange that I was saying that as I was still hitting the times and doing sub five-minutes in mile repeats. He said that despite the excuses I was piling up that I was ready, so I pushed aside the excuses and ran.

“The race itself was terrible as I missed a water bottle, I got tripped but I was still putting my head in it. It was a great lesson that the micro decisions we make are so critical to our success. To me that was the finest moment.”

This year’s Triangle Challenge athletes will get the chance to compete alongside Kastor, who will be running the Butterfield Mile on Friday night, and she is keen to mention the attraction Bermuda offers to runners with this event.

“I’ve just come from 4ft of freshly fallen snow, so I think this is heaven,” Kastor said.

“For someone who experiences big-time winter this is a great destination to break up the monotony of snow and cold. I can’t think of better timing for this race and to be able to enjoy some warm weather. Although the weather here might not be ideal for Bermudians right now, for us mountain folk it’s ideal.”

It’s a joy to listen to Kastor, with every sentence a heady mixture of inspiration and emotion and runners at the Pasta dinner will be in for a treat when she takes to the stage to speak, although perhaps her daughter might want to close her ears if her mom mentions her proudest moment away from marathon running.

“I think I’m supposed to say my daughter but that’s not my answer,” Kastor said.

“I would say writing my book because that is the hardest thing I’ve ever done but it’s also where I could see in the moment that I could make the biggest impact on people. It’s all about the power of positivity and performance so being able to write from that perspective to show that working on your head space is so critical to living your potential in any moment. That was the time that I knew I could empower people to do what I do.”