This story is from Manual, GQ’s flagship newsletter offering useful advice on style, health, and more, four days a week. Sign up here to get it in your inbox. It seems like everybody’s in a run club these days, so it’s no surprise that Zone 2 training, once used primarily by serious athletes, has become the go-to workout of the moment. “This has been the staple of endurance sports for close to a hundred years,” says Scott Johnson, coach at Evoke Endurance and co-author of Training for the Uphill Athlete. “I just think it got lost. Twenty years ago, the pendulum swung really hard to high intensity interval type training—HIIT—which was kind of popularized by CrossFit. Now we’re seeing the pendulum has swung back in the other direction more towards the more traditional aerobic base training.”
Zone 2 training, also known as the “sweet spot” or “easy” training, is a method of exercise that falls within a specific heart rate range. It’s characterized by a moderate intensity, allowing for sustained effort without pushing your body to its absolute limits. The benefits of Zone 2 training are numerous and far-reaching. It’s a highly effective way to improve cardiovascular health, boost endurance, and enhance fat burning.
That’s exactly how it should feel. “It’s an easy pace—you can have a full-sentence conversation while you’re doing it,” says Channing Muller, a Chicago-based certified running coach. If you’re struggling to get more than a few words out without catching your breath, you’re going way too fast. Zone 2 might seem paradoxical—you have to run slow to eventually run fast. But training at a lower intensity actually helps you build a stronger aerobic base. If your goal is to improve your aerobic threshold, the point at which your blood lactate starts to rise and your body starts to rely on anaerobic energy sources, “the only way you can do it is to gently nudge it from below,” says Johnson. “You cannot drag it from above.”
Use an Accurate Heart Rate Monitor When I started Zone 2 training, I was using an old Apple watch with a wrist heart rate monitor; my heart rate would jump to 165 as soon as I picked up my pace from a walk to a run. When I took my pulse manually, it was actually 20 beats per minute lower than my watch suggested. Lesson learned: Use an accurate fitness tracker. While wrist-based heart rate monitors are common and convenient, their accuracy can vary between brands, models, and even how they fit. For the most reliable readings, consider using a chest strap.
