MacArthur's love for sailing dates back to when she was just four years of age, when she first got the opportunity to have a try. "I'll never forget that feeling as a kid of setting foot on a boat for the first time," MacArthur said. "It's kind of struck me that this boat had everything we needed to take us anywhere in the world. And as a child, that opened up everything," she explained how it felt like the "greatest sense of freedom".
This experience lighted a passion within MacArthur. She knew then that she wanted to sail around the world. She had no idea how to achieve it — growing up in the countryside, it wasn't the most obvious career path — but she knew that was what she wanted to do at some stage. So, she acquired knowledge and saved up for years to seek a career in sailing. She would have potato and beans every day for eight years so that she could save up to buy the right equipment. By reaching certain financial goals and asking technical questions about sailing, MacArthur felt as though she was getting closer to her ambitions.
"When you know where you're going, you can actually get there — even if it seems impossible. The impossible could be possible and aiming high is not necessarily such a crazy thing to do." And it seems that MacArthur's drive to become a sailor went beyond her expectations. At the age of 24, she started to receive media attention after participating in the Vendee Globe, a single-handed non-stop yacht (游艇) race that goes around the world. She came in second place. Some three to four years later, MacArthur chose to sail for 71 days and 14 hours, covering more than 26,000 miles during the course of her journey. This led to MacArthur scoring a new world record in 2005, as the fastest person to sail around the globe single-handedly. While this record has since been surpassed, MacArthur is still considered as Britain's most successful off shore racer.