Back in January I wrote about a free Denver running club at Nike, framed as a way to keep up on those New Year’s resolutions to start running. But as e-mails came in about other free running clubs, I realized Denverites don’t need to make resolutions to run; it’s what we love to do. Another free club is the Denver Trail Runners, which meets weekly on Thursday evenings. There’s very little to worry about if you run with this group: There's no required sign-up or dues. (Which, frankly, I appreciate. Sometimes even having to sign up for a running group deters me.) You simply register for the weekly e-mail to find out where they’re meeting and where the run is that week. Dogs and baby strollers are welcome. As a runner who prefers the flattest surface possible, I’m excited to try this club, but I'm also a bit intimidated to run uphill. Luckily for wimps like me, the members' performance levels range widely and include simply walking and hiking. Bonus: In Boulder? Check out the Boulder Trail Runners, which schedules even more weekly runs, including a happy-hour run at 5:30 p.m. on Thursdays. The hour-long run is followed by drinks at Sherpa's.