The riders took off in a pack of clicking gear and churning muscles - but few were huffing just yet.
It wouldn't be until the finish line, yards from where they started their 4-mile, 9-mile, 14.5-mile or 18.5-mile ride that they'd be red-faced, but many smiling and excited to complete Wednesday's second race in the Summit Mountain Challenge mountain biking series.
"The course is loose, it's dry, it's classic Colorado mountain biking out there," event organizer Jeff Westcott said through the PA system.
Many took to the trail, racing for the first time this summer or in their lives. Like Dennis Flanagan, who's heart is in trail running, but he decided to sign up for the mountain biking series this year.
"I love trail running, but it's so great to get on two wheels," he said. "It's a party every Wednesday and I just wanted to be a part of it."
For him, the hardest part is staying in control on the downhills, though he likes cruising the steeps.
On the flip side, the hardest part for second-place finisher Nate Vacura in the men's beginner class was the last hill, known as Heinous Hill. He didn't carry his bike, even though he started mountain biking two years ago and his friends only just convinced him to join the race this year.
For women's beginner class fourth-place finisher Suzy Baver, the feat of merely finishing was her drive.
"It was tough. It wasn't that long of a distance, but there's some steep climbs and some ballsy downhills," she said of the 9-mile beginner course. "There's some great athletes in this area to be competing with as a hobbyist. It's pretty cool."
She'd been trying to get up the courage to race for several years, and this year she opted in with the mentality that all she needed to do was finish. She beat out five other women in the same class in her first race.
On the opposite end of the spectrum from these beginners are the men who are upper-level gear bike racers and opt to use one speed throughout the race. They select the gear, set up their bike and are limited to that speed for the 14.5 miles they're racing.
"I'm always second-guessing myself," winner Jesse Swift said, explaining that he chose a different gear than second-place finisher Kristofer Carlsted.
Out of the gates, Carlsted left Swift in the dust, but once they reached the first hill, Swift pulled ahead. He thinks he had the advantage by a mere gear tooth, though both hiked Heinous Hill.
"It's a unique challenge," said Dan Teodoru, an attorney in Breckenridge who sometimes races in the series and occasionally takes to single-speed biking, but wasn't geared up on Wednesday. "It's simple. You grind along as best you can and when you can't, you throw your bike on your back."