ST. AUGUSTINE, Fla. -- Mike Pennington of St. Augustine didn’t like retirement, so he decided to try something new. Not golf, not checkers. Instead, he gave triathlons a try!

Little did he know he'd end up at the Ironman World Championship, which he is training for now.

"It’s a two-mile swim, a 75-mile bike race, and an 18-mile run," Pennington said as he took a break from training at the Solomon-Calhoun Community Center in St. Augustine.

He is 72 years old and will compete in the 70 – 74 year old age bracket.

This interest in triathlons kick-started about three years ago after Pennington’s daughter was training for one. Pennington remembers asking, "What’s a triathlon?"

When he heard it was a "bike, swim, run" he said to her, "'I think I can do that.' And she said, 'No, I think you’re too old, Dad.' So bang! Challenge on!"

He has taken on that challenge with fervor! Over the last three years, he has done 15 triathlons, placing sixth in nationals, which has now qualified him for the Ironman World Championship this summer in Canada.

"I think he’s awesome," Craig Teeters, Pennington's swim coach said. "About a year ago, his swimming skills were very poor at best, and now he’s swimming at a very high level."

This septuagenarian is now excelling, but he is not splashy about it.

"There are some pretty fit old people you know," he said. "Seriously, its very competitive. They’ll swim over you, knock over you, and bounce over you. It’s amazing!"

Another person, Mel Phillips, from St. Augustine will compete in the Ironmn World Competition.

"He’s kind of my hero," she said. "One of the last races we went to, he won his age group. I see him walking, carrying all his gear, not looking tired. He’s so fit. And I think he’s generally a wonderful person."

Pennington’s wife – who may be his biggest cheerleader – said he is not just wanting to compete, he wants to do well.

"I’m not under an illusion that I will win," he said. "It’s a massive competition for me. But I want to do well, yeah."

He said age is not an issue for him, but keeping fit is.

"If you don’t use it, you lose it," he said. "It’s cliche, but true. I’m determined to go to the end."

He said the end could be the championship circle or the end of his own personal path.