It all started when his ex-wife kicked him out of the house.
"She kicked me out of the house, and I had to think of things other than how I could get even with her, so I started stair climbing and racing star climbing," said Keith Wood, a native of Sydney, Australia. "And I broke records immediately on that."
Now, at 84-years old, Wood has shifted his focus to long-distance running, and completed the Summer Roundup Trail Run in 1 hour, 41 minutes (12-kilometers), averaging about 13:40 per mile.
As he crossed the finish line at Bear Creek Park on Sunday morning, his black bandana dotted with white skull and cross bones still securely fastened to his head, Wood's face spread into a toothy grin. He was the first, and only runner to cross the finish line in the 80-84 age group.
On the opposite end of the spectrum was 9-year-old runner Alden Kruse who was competing in the Summer Roundup for the second time. He finished second in his age group and about 20 minutes faster than Wood.
"He was running really fast," Kruse said of Wood. "When I saw him, I was like, I can beat this guy. It was fun."
Wood has already run in the Garden of the Gods 10-miler and plans to compete in both the Pikes Peak Marathon and Ascent. If he finishes one of the two Pikes Peak races, then he will complete the Colorado Springs Triple Crown, a feat that he's accomplished a few times before. In 2009, Wood set a new course record for his age group in the Ascent at 4 hours, 51 minutes.
The overall Summer Roundup winner, 24-year-old Andy Wacker of Boulder, didn't know until after the race that he was sharing the course with a man 60 years his senior, but he was impressed with Wood's dedication and endurance.
"I can't imagine that," Wacker said. "I can barely imagine it this year doing it as a 24-year-old. So much respect, and that's just an amazing race. I can't imagine doing this race and then both the Pikes Peak runs."
Race officials said Wood is the oldest participant in the Summer Roundup, and he's used to being in a class of his own. Four years ago, he competed in the race for the first time at 80 years old, and he believes he was the first 80-year-old to do so.
Wood also ran in the Boston Marathon two years ago, and was the oldest competitor at 83-years-old. He's already qualified for the race in 2014.
To train for the Colorado Springs Triple Crown of Running races, Wood leaves his home in Washington and heads to the mountains of Colorado and trains at the higher elevation. This year he camped for two weeks between Mount Massive and Mount Elbert.
"I've got an old Suburban up there, I don't know what's going to die first, it or me," Wood said. "But I sleep in it and I do my training outside of Leadville. It's a real rough road so you have it all to yourself, but on the 4th of July it was like a freeway."
Wood was a cyclist and hill climber before he took up running more than a decade ago in his early 70s.
"I fell off my road bike coming down at a heck of a speed coming down from a 4,000 foot pass at 75," Wood said. "And that knocked me for a couple years. It hurt my hip, but hasn't affected me outright."
As he's aged, Wood has suffered a few setbacks, including a shortened stride that has slowed his pace, but he said that his cardiovascular system is doing fine.
Wood doesn't have any plans to compete next year because, he said, he has too much to do.
But he'll most likely be back - as long as there's an age group for him to compete in.
Numerous course records fell, including Wacker's overall first-place finish of 44:33. He broke the course record for 20-24 men that was previous set by Aaron Rubalcaba-Lopez in 2010 of 45:20. Wacker said that the run was good training for the U.S. Mountain Running championships, held in two weeks in New Hampshire.
Peter Fleming, a 52-year-old from Colorado Springs, set a course record for the 50-54 age group (49:04), nearly four minutes faster than the previous record.
For the women, Nicole Mericle, 25 of Boulder, set a record for her age group by nearly a minute. Mericle led for half of the race, but was passed by Ashlee Nelson, 32, of Colorado Springs. Nelson finished first, setting a women's overall course record. Her time of 51:26 came in just under Samantha McGlone's time of 52:43 in 2008. Nelson's time also set an age-group course record by three minutes.
There were about 700 competitors.