Around the world in 80 days is not nearly fast enough for runner Becca Pizzi, who recently ran seven marathons, on seven continents, in seven days.

The feat, completed over the weekend, makes Pizzi the first person to ever to run the World Marathon Challenge twice. In the race, athletes transitioned from below-freezing Antarctica to Colombia, where it was 80 degrees — with 90 percent humidity. Pizzi says the constant travel makes the experience particularly challenging.

“We cross 16 time zones and that’s always exhausting, but the temperature change is tiring and fatigue sets in,” she told Jim Braude on Greater Boston.

When asked what makes someone want to run these marathons, Pizzi joked, "we're crazy.” She said the drive to complete a challenge like the World Marathon comes from wanting to test your own endurance and strength.

Pizzi ran the final stretch of the marathon with her daughter, whom she calls her number one fan and biggest inspiration. 

“When I saw her in the last 100 yards to run through the finish line and we threw our hands up, it was the greatest day of my life,” she said.

Pizzi holds the record for fastest women's time after running the 2016 World Marathon in just 27 hours and 26 minutes.

"I say dream big, take chances, and believe in yourself," she said. "Find your world marathon challenge. Find what it is that you’re passionate about. And if you believe that you can do it, you can do it,” she said.

As for her next goal, Pizzi said she is working toward running a marathon in each of the 50 states. So far, she has competed in 33 states and aims to run marathons in the remaining 17 by the end of the year.

This post has been updated.