Going to the gym for specialized workout classes have become the norm for many. Whether it’s a classroom full of bicycles or rooms designed for HIIT training, students love environments that can simultaneously push and encourage them. But sometimes—for those who don’t have the time to travel to those gyms—exercising can be tough. That’s where connected devices and equipment like Mirror and Peloton pushes fitness to another level by connecting health enthusiasts to their trainers online. The key is the right technology.

Connected fitness started out with apps and then moved up to wearables, where people could monitor steps and heart rate through their watch. Today, connected devices are getting bigger and more interactive. Smart home-workout equipment and membership packages get people to attend instructor-led classes from the comfort of their own home. And the trend continues to grow. MarketResearch.Biz published a report that states fitness and wellness in the healthcare market is expected to see a compound annual growth rate of 26.6 percent. VentureBeat writes that the health club industry generates $83 billion in revenue around the world each year.

Peloton, the smart fitness company that uses stationary bikes and treadmills with interactive screens, has sold more than 400,000 since late 2013. NYMag writes that this workout is the closest experience to an in-person class thanks to like HD screen and leaderboard. Live DJs, themed playlists, and teacher shout-outs also keep people coming back for more. Built In NYC writes that Peloton’s leaderboard harvests large amounts of data—the board changes constantly in real-time response to more than 20,000 participants. The company’s team also updates the software every few weeks so that each bike has a customized operating system.

Mirror, an interactive monitor that disguises itself as a typical mirror, includes prerecorded workouts like yoga, cardio, and Pilates. Launched in 2018, it received an inaugural $13 million of funding. The New York Times writes that Mirror, which retails for $1495 plus a monthly subscription, was selling $1 million of screens per month, or 650 units. Other popular connected fitness devices include boxing system FightCamp, strength training-based Tonal, and the Hydrow Rower.

The keys to the success of these devices are plenty. Because they are so interactive through instructors giving real-time feedback, students get the excitement of an in-person class while being at home. Seeing metrics on the devices help gamify the experience as well, adding a fun and competitive aspect.