Thousands of people came to Chattanooga over the weekend for the Little Debbie Ironman Triathlon. It’s a competition fit for the fittest.

“I’m not too nervous,” athlete John Marino said. “The heat's going to be the biggest thing. But I think a little bit of physical suffering, a little mental suffering is good for the body."

The race starts with a 2.5-mile swim in the Tennessee River, followed by 116 miles of cycling, all topped off with a full marathon. The challenge is not for the faint of heart.

“It's just such an accomplishment it really is,” Austin Sparks said. “And I’m ready to do more, it's an addiction kind of."

Athlete Brenda Worell says it's all excitement until she settles in for the long road ahead.

"The nerves of the morning have dispelled because you're now into it. This is what you've trained for so you've done it every day,” she said. “It's like 'ok, it's a long training day.'"

Sparks is on his third Ironman challenge. This time around, he found a new way to stay motivated.

"I told my wife last time I said, don't encourage me,” he said. “I want you to yell at me like a drill sergeant, 'don't stop or I'm going to divorce you.' So that helps a lot."

But Sparks says positivity does come in handy.

"Halfway through you get a little bag, it's a special needs bag and I have my family write a note of encouragement and that helps for the last 13 miles,” he said.

Marino has a different strategy. He's placed his eyes on the finish line.

“Excited and then ready to go to bed, eat a lot of food. I can eat whatever I want for the next week,” he said.

Worell though, says she's just happy to keep running.

"Because by the time you run one of those things at my age, you're walking some,” she said.

More than 2,000 athletes registered for this year’s competition. You can see the final finishers come in at Ross’s Landing Sunday at 10 pm.