Sure, spin class feels killer, but outdoor cycling may require you to work even harder, according to a study in Journal of Strength and Conditioning Research. Plus, “there’s something really nice about covering distance and being in the fresh air and sunshine,” says Jim Rutberg, a cycling expert for Carmichael Training Systems and Strava in Colorado Springs, Colorado. He created the 30-minute interval workout below. If you’re a beginner, try doing the workout in a loop first so you can log the distance without getting too far from home. Once you feel comfortable, turn it into an out-and-back ride and explore some new terrain.