If you look past the three indoor cycling studios on your block, chances are you'll spot a new type of fitness boutique: group treadmill classes. While running is often a solitary endeavor, these classes help train students in ways that aren't always possible when going at it solo. Whether you find yourself cranking up your treadmill to a 10 at Barry's Bootcamp [1] or running up what feels like a mountain before being tasked with a set of push-ups at Burn 60 [2], you're pushed to go faster and climb harder than you ever would outside on your own. And it's not just textbook runners you'll find in these classes. Moving back and forth between high-intensity treadmill intervals and strength training also makes for an enticing workout for anyone looking to challenge themselves and loves the motivation that comes from a group workout.

As is the case with most fitness trends, the vast majority of treadmill classes are found only in big cities. But that doesn't mean you can't get a little taste of the fitness trend for yourself. The below workouts come from some of the most popular treadmill classes in the country and can easily be done at the gym.

• Barry's Bootcamp: While classes at Barry's Bootcamp alternate between running on a treadmill and strength-training sets on the floor, this 30-minute treadmill workout [3] from trainer Alycia Stevenin is a good example of what the running segments are like. Expect a tough run full of intervals and hill training to test both your endurance and speed.
• Burn 60: Much like the Barry's Bootcamp formula, Burn 60 challenges its students to perform running along with total-body strength training. This simplified version of the studio workout [4] combines high-intensity treadmill intervals with total-body strengthening moves. While you can turn this into an hour-long workout to get a true Burn 60 experience, one round lasts 20 minutes, making it a perfect workout for days you are pressed for time.
• Tread and Shred: A constant on Equinox's class schedule is its popular Tread and Shred class. While the class incorporates bouts of sprinting, what really sets it apart is how the teachers utilize the treadmill as a tool for total-body strength training [5].
• Precision Running: Unlike the majority of classes that split time between running and strength training, Equinox's Precision Running class takes places solely on the treadmill. Led by a running coach, the workouts are meant to help you become a stronger and faster runner by focusing on speed, incline, endurance, and proper recovery. Trainer David Siik, the creator of Precision Running, developed this 25-minute pyramid speed workout [6], which will help condition the body to become faster while protecting it from injury.