Committing to a gym membership can be hard, especially when it comes with a hefty price tag and unfamiliar equipment or workouts. FIT36 is here to help, with a free-week trial program that lets you get in and get comfortable with classes and equipment before signing on the dotted line. FIT36's signature workouts take 36 minutes at most, and all are based on high-intensity interval training (HIIT). During your free week, try FIT36's "push, pull, pulse" system, or work with trainers to challenge your fitness and adjust your form. The flagship location is downtown, and there are outlets all around the Denver metro area, so get moving: This introductory gym package offers big bang for your buck (or lack thereof).