Heart and Sole, which hosts an annual 10K and half-marathon at the Boulder Reservior, added a stand-up paddleboard race to the day’s festivities. The SUP Cup offers a 1K novice and three-mile elite race. Sun 8:15 a.m.-noon. 

No need to change into short shorts and a singlet—you can roll out of a bed and run this 5K. Sleep Tight Colorado wants you in your pj's for its annual fundraiser. A costume contest kicks off things. Sat 8-10 a.m.

Test your athleticism and wit during this race. Teams complete obstacles and solve clues in ten- to 30-mile on a mystery course around Denver. Start at the Downtown Aquarium, then grab a beer at the secret finish line—wherever it is. Sat 8 a.m.

Locals and world-class competitors race head-to-head in either a 750- or 1500-meter swim in the Boulder Reservoir. An optional 5K run immediately follows the swim, and a generous spread of food waits all at the finish. Thu 6 p.m.

This 5K is half foot race, half paint party. Runners are blasted with neon paint along the course, which ends in a blacklight-illuminated after-party. Stick around for the post-race concert. Sat 8 p.m.

Cycle from Denver to Winter Park along one of Colorado's most scenic routes. Starting at City Park, you'll trek past Lookout Mountain to Boettcher Mansion, Buffalo Herd overlook, and up Squaw Pass to Echo Lake. This social ride is 96 miles long and gains 10,117 vertical feet. Sat 7 a.m.

Cyclists take a scenic and challenging 106-mile century ride through and around Front Range landmarks and mountain towns. The total elevation gain for this route is approximately 10,000 feet and includes a climb up Squaw Pass. Sat 6 a.m. 

If you thought your childhood playground antics were long behind you, think again. This competition pits teams of 12 against each other in various elementary-school games. Past contests have included human foosball, wiffle ball, and (what else?) dodgeball. Heads up: Registration closes Wednesday, June 5, so act fast. Sat 9 a.m.-4 p.m.

Kick your family off the sofa and bring them to this recreational paradise. Peruse traditional and non-traditional outdoor activities–from mountain biking to geocaching–that your family can enjoy on site. Sponsored by Get Outdoors USA!, this festive day also includes invites families to follow-up activities at local parks.

Soothe mind and body with a trio of yoga classes by Platte River. Each monthly session raises awareness for a seperate cause–helping those with physical disabilities, homeless urban youth, and the South Platte River's preservation. Fri Jun 28, 7 p.m.; Fri July 26, 7 p.m.; Fri Aug 23, 7 p.m.