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.”
For those of us who grew up thinking that exercise meant pushing our limits, easy training in Zone 2 can feel strange—despite the fact that it’s actually really good for us. Also: saying you’re going out for a Zone 2 workout versus actually doing it? That’s a different story. Ego can get in the way, and people tend to push a little too hard. Here’s how to really dial it in.
Understand What Zone 2 Feels Like
Training with heart rate divides your cardio workouts into (usually) five different zones of intensity: Zone 5 is all-out, while Zone 1 is barely more strenuous than sitting on the couch. Zone 2 is just a bit harder than that. If you’re new to Zone 2 training, working at this low intensity might feel almost too easy. You might wonder: Is this actually doing anything for me?
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.
To properly train Zone 2, you need to know your heart rate zones. A lab test will give the most accurate results, and your device might take a guess, but the simplest way to estimate your Zone 2 heart rate range is by using a formula. One common method is to determine your maximum heart rate (220 minus your age), then calculate 60 to 70 percent of that number—that’s your aerobic threshold, the very top of your Zone 2 range. Another popular method is the MAF formula, developed by Phil Maffetone, which suggests subtracting your age from 180. Both of these formulas can give you a general idea, but they don’t account for many individual nuances.
