Area native to run 1st Bank of America Chicago marathon after losing over 200 pounds

CHICAGO (WLS) -- Pre-race festivities kicked off Thursday for the 45th annual Bank of America Chicago Marathon on Sunday.

More than 45,000 runners are looking to log 26.2 miles through dozens of Chicago neighborhoods.

The Abbott Health and Fitness Expo was just getting going at McCormick Place Thursday morning.

The tens of thousands or runners at the marathon expo included plenty of first-timers, just hoping to finish, as well as marathon veterans hoping for a personal record. A third of the field is made up of international runners from 120 different countries.

"This is my first time coming here. My goal is to run my personal best," South African runner Kurhula Bilankulu said.

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From an Edgewater priest, to the breast cancer survivors, so many runners have inspiring stories, including Carmen Nacci.

The Chicago native has dropped more than 200 pounds over the last nine years.

Crossing the finish line on Sunday will carry special meaning for the 33-year-old.

Nacci joined ABC7 Chicago Thursday to talk more about it.

Potentially the fittest group of 70-something's around are also running the race.

First-timers and veterans attended the Chicago Marathon expo Thursday.

They've run every Chicago marathon -- 44 straight. They're going for 45 Sunday.

The group used to be much bigger.

In 2017, there were seven; now there are three.

"It's come to the point, it's 'how can I not go?'" George Mueller said.

"Running keeps you young, right? As long as you can keep it all together, and it's not easy," Randy Burt said.

The race is also a big financial engine for the city, with economic impact estimates of more than $300 million over the weekend.

"This is the Super Bowl of running, so it's incredibly important to us," said Dave Zimmer, with Fleet Feet.

It's also important to the city. The marathon course travels through 29 Chicago neighborhoods.

"To experience the culture of the city, the neighborhoods are the best way to get it. And that's what makes this event so important in the mayor's eyes," said Glenn Eden, with Choose Chicago.

The largest field ever is expected for the race: 47,000 are signed up to be at the starting line Sunday. And they have lots of family and friends with them.

There are 1.7 million fans expected to line the course.