What’s your motivation to exercise? Weight loss? Heart health? How about cookies? How about not just any kind of cookie, but one of America’s favorite cookies-for-a-cause, the Girl Scouts’ Thin Mints?

If you’re willing to sweat for one of these delightfully delicate minty treats—simultaneously helping the Girl Scouts of Southern Arizona and earning your own honorary Girl Scout badge—register now for this Sunday’s early-morning fifth annual Thin Mint Sprint, a timed 5-kilometer race that includes a Thin Mint reward at the finish line. The same morning will offer a shorter Do-Si-Do Dash.

Both races are on a flat course through the Brandi Fenton Memorial Park and along the Rillito River Trail, and both are timed—although racers are welcome to either run or walk. Families, teams and individuals are encouraged to enter. The race course is, according to a press release, “ideal for new runners as well as elite runners looking to beat their personal record.”

As icing on the cookie, there will also be a children’s 100-meter dash for kids 6 and younger, so bring the little ones.

The Thin Mint Sprint and Do-Si-Do Dash start at 7:30 a.m. Sunday, Sept. 18, on the northwest side of Brandi Fenton Memorial Park, 3536 E. River Road. Registration is $25 for adults, $20 for kids 12 and younger. Race-day registration is available from 6 to 7 a.m. More info here.