GETTING HOTTER OUT HERE. IT WAS PRETTY COOL THIS MORNING AS WE STARTED. >> IT FELT PERFECT, THE RIGHT TEMPERATURE TO GET IN THE WATER. >> BUT NOW THE SUN IS UP AND IT'S BEAMING DOWN. I FEEL FOR THESE ATHLETES. THEY'RE WORKING HARD RIGHT NOW. WE ARE LIVE RIGHT BY THE FINISH LINE. WE'RE IN THE NEXT FEW MINUTES. WE ARE EXPECTING THE FIRST ATHLETE TO CROSS THAT FINISH LINE. AFTER STARTING JUST A COUPLE OF HOURS AGO AT 6:00 THIS MORNING. SO LET'S TALK A LITTLE BIT MORE ABOUT THIS RACE. OBVIOUSLY THESE ATHLETES ARE BEING TESTED PHYSICALLY. THEY'RE BEING TESTED MENTALLY AS WELL AS THEY COMPETE IN THIS LONG SWIM BIKE AND THEN RUN THE COURSE STARTED IN LAKE MICHIGAN AT, UH, ONE OF THE HARBORS THERE FOR ATHLETES TAKE OVER CITY STREETS. THE TRIATHLON ALSO HAS A CORPORATE CHALLENGE, WHICH HAS RAISED MORE THAN 50 K FOR PEDIATRIC CANCER. AND BLOOD DISORDER RESEARCH AT LURIE CHILDREN'S HOSPITAL, WE SPOKE WITH THE CEO OF SUPER TRI, THE COMPANY OPERATING THE CHICAGO TRIATHLON, ABOUT WHAT MAKES THIS EVENT SO SPECIAL. >> CHICAGO TRIATHLON IS A IS NOW THE BIGGEST EVENT IN NORTH AMERICA. I BELIEVE THE SECOND BIGGEST EVENT IN THE WORLD. SO AND IT HAS A LONG HISTORY OVER 40 YEARS AND THE IMPACT IT HAS ON THE COMMUNITY, NOT ONLY IN CHICAGO BECAUSE I'VE MET PEOPLE, I MET SOMEBODY WHO DROVE IN FROM NEBRASKA THIS MORNING. SO IT HAS AN IMPACT ON THE WHOLE TRIATHLON COMMUNITY ACROSS NORTH AMERICA. THAT'S THAT'S MASSIVE. NOW BACK HERE, LIVE ALONG COLUMBUS DRIVE . >> TAKE A LOOK AT THE VERY FIRST ATHLETE HAS CROSSED THE FINISH LINE RIGHT HERE. A REMARKABLE AMOUNT OF TIME. DID NOT TAKE LONG FOR THAT TO HAPPEN WHATSOEVER. NOW REMEMBER SO MUCH TIME AND EFFORT IS SPENT TRAINING FOR THESE TRIATHLONS. THERE'S THAT LONG SWIM THEY HAVE TO GET THROUGH THE BIKE, RIGHT? OF COURSE. AND THEN THE RUN. SO HATS OFF TO ALL THESE ATHLETES COMPETING TODAY. WE'RE