LOUISVILLE, Ky. (WDRB) -- Nearly 3,000 athletes will descend on downtown Louisville for Sunday's grueling IronMan competition. 

On Friday, many the athletes were at IronMan Village on the waterfront as they completed the registration process, got their bikes tuned up and even enjoyed a last-minute massage. 

Competitors must complete a 2.4-mile swim in the Ohio River, a 112-mile bike ride and a 26.2-mile run through Louisville and its surrounding areas. The bike course takes athletes out of Louisville, toward Oldham and Henry counties and into La Grange.

The running course is flat and passes the University of Louisville campus and Churchill Downs before finishing at Fourth Street Live!

Timmy Gallagher, an IronMan athlete who has been training hard for the past year, told us what motivates him. 

"It's a sense of you're part of something bigger," Gallagher said. "And you're pushing boundaries of yourself, and you're sharing that will all the other athletes, which I think really is what life is about. That's why I do it."

Weather could play a major part of the race this year. As of Friday evening, the WDRB Weather Team says showers and thunderstorms are possible on Sunday in the late morning and mid-afternoon.

“If it rains on the bike, you just have to go a little slower, be a little more cautious and watch other people,” athlete Stewart Mickler said.

“We're always watching for extreme weather,” Dr. Ryan Modlinski said. “It might rain and thunderstorm, and lightning storms might have to precipitate us to clear the course for a short period of time or runners might have to run through rain and puddles.”

About a dozen Norton Health Care tents will be stationed along the route, including hundreds of medical professionals.

“We have the traumatic bike injuries, a lot of collar bone fractures or clavicle fractures when they fall,” Modlinski said. “They're usually clipped in, so they tend to go over the handle bars, so we see a lot of fractures. We see a lot of heat illness type of injuries, so they are just generating more heat than their body can disperse. [We also see] hyponatremia, which is low salt content. So you are taking in a lot of fluid, but you're sweating out a lot and you're losing more salt than you’re taking back in, so that can cause neurological deficits

More than 40 Louisville Metro EMS workers will be along the route, in the water and on bikes with 12 ambulances stationed.

We have over 40 employees assigned to the event from the beginning until the last run crosses finish line.

There will also be a Mass Casualty Incident Bus on site and equipment placed throughout the venue in case of emergencies, according to Louisville Metro EMS.

A number of streets will be shut down on the day of the competition. On Sunday from 5 a.m to 6:30 p.m, Witherspoon from Preston Street to Bingham Way will be shut down.

River Road from Third Street to the westbound I-64 ramp will also be blocked until 6:30 p.m. as will River Road from Preston to Witherspoon Street.

Traffic will be allowed to access River Road Sunday morning after the bike ride is complete. The eastbound lanes of River Road are expected to open around 1 p.m.  

Click here for a full list of road closures or see the attached pictures below:

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