Nearly 1,000 athletes were scheduled to compete, according to South Shore Convention and Visitors Authority director of sports development Jason Sands, in only its fourth year since the event was revived.
"My involvement came about five years ago when Leon Wolek came to us and he wanted to restart the event," Sands said. "It was one of the bigger triathlons in the '80s and '90s and it became a huge community event."
In the Olympic-length triathlon, amateur athletes swim 0.9 miles in Wolf Lake, bike 24.6 miles on a shut-down portion of Cline Avenue and run 6.2 miles through Wolf Lake Park.
Wolek started the race in 1983 in Hobart, where it was run at the Izaak Walton League until it outgrew that space, and Wolek was invited to stage the race at Wolf Lake by then-Hammond Mayor Thomas McDermott Sr. The popular event was televised on ESPN, and was billed as the world's fastest because of its flat course. But the race took a 15-year hiatus starting in 1997 when the Trump Casino balked at shutting down a stretch of Cline Avenue for three hours.
"The event is such a major production that you can't do it for a couple months of the year; it's literally a year-round production to prepare," Wolek said. "What happened way back then was there were a lot of moving parts in transition, politically and in business. So we collectively decided that all of the pieces were not there to operate in unison."
Wolek said competitors and fans of the event asked him often about restarting the event, but it was only through a conversation with McDermott's son - currently Hammond Mayor Thomas McDermott Jr. - that got the ball rolling again.
"I told him, ‘If we're going to do it, we've all got to be committed. I don't want to do it halfway'," Wolek said.
Sands said the SSCVA looked at other triathlons - in particular the Maytag Ironman 70.3 Steelhead race in St. Joseph, Mich. - for inspiration on how to run an event the right way.
"It's a signature event for the community," Sands said. "They get excited, and the athletes come in eat and stay. We're hoping to be booking up to 1,000 hotel rooms, but what's more measurable to us is the showcase it provides for Northwest Indiana.
Comcast SportsNet taped the event and will broadcast it July 4.
But for Wolek and many of the competitors the event goes beyond a race.
The event always has had a military emphasis, from a 21-gun salute and flyover to open the race to the race serving as the military championship twice in the 1990s. But many of the triathletes are running to raise money for veterans in crisis.
"Team RWB (Red White and Blue) is creating communities across the country to reach out to people who are in a dark place," Wolek said. "When soldiers come off the battlefield, they have all of the flashbacks, and some end up addicted and lose their lives through suicide.
"It really affects me so much because they give up their lives for us."
Beyond the military, triathletes race for a variety of charities, including the Leukemia and Lymphoma Society's Team In Training, Team To End AIDS, ALS, and animal welfare groups to name a few.
"I just feel so obligated to do everything I can to help these organizations," Wolek said. "It's turned into something from the heart."
Chicago resident Sally Stresnak competed in her second-straight Leon's Triathlon on Sunday.
"Today was a rough day," Stresnak said. "Typically, the swim gets in my head. But every time I struggle I just think of why I'm out there (for Team To End AIDS).
"It's a cause near and dear to my heart because I've lost friends to the disease. As long as we deal with this problem for all humanity, I'll be out here."
Chicago resident Jim Rochford finished his first triathlon as a member of the the Leukemia and Lymphoma Society's Team In Training.
"My cousin has leukemia," he said.
It was the first triathlon for Elgin, Ill., resident Dick Johnson, but he's ran marathons with the Leukemia and Lymphoma Society's Team In Training for several years.
"My next door neighbor was involved and I considered walking the marathon, but (Team In Training) provides coaching and soon enough I was doing it," Johnson said.