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Sometimes I fear my running career has plateaued. Well, not my career, but my pace. I lace up four or five times a week, push hard enough to feel pleasantly wrecked, watch my mileage climb steadily upward, and then—after months of honest effort—still find myself running the exact same pace I was running a year ago. It’s clear that in order to get faster, effort alone isn’t enough.
I’m not alone here. It’s well known in running circles that a lot of us unconsciously settle into what coaches call “the gray zone”—an effort level that’s too hard to be truly easy and too easy to create meaningful high-end adaptation. It feels productive, but from a physiological standpoint, you’re collecting fatigue without collecting much additional fitness.
I see a lot of competing advice from “runfluencers” online, usually focused solely on everyone’s favorite workout: Zone 2 cardio (and all the ambiguity that entails). However, Zone 2 alone isn’t going to help you break through your plateau. The best way to improve your running can be boiled down like this: Slow down on your easy days, and go harder on your hard days. But understanding why requires a short detour into how your aerobic system actually works.
What “Zone 2” means for your running
If you’ve been anywhere near running content in the last few years, you’ve heard about Zone 2 training. It’s practically been evangelized, and I get it—who doesn’t want to hear that less effort can yield greater results. The idea has genuine scientific backing, and it’s useful for runners who chronically overtrain. But it’s also become a buzzword that gets thrown around loosely enough to cause confusion.
“Zone 2” is a term drawn from the five-zone system of heart-rate training. For runners specifically, this zone translates to “easy pace” or “long slow distance pace.” The tricky thing is that for most recreational runners, this pace is far slower than it feels like it should be.
There’s a reason the sort of “moderate intensity” runs I describe above—where you could hold a conversation, but it wouldn’t be comfortable—are sometimes called “junk miles.” It’s not that these miles are without benefit: Running is still good for you! But if you spend the vast majority of your training at “moderate intensity” (or zone 3, or the gray zone, or running junk miles), you’ll struggle to get faster. In order to go intense enough to really push your aerobic ceiling, the rest of your miles need to be easy enough to recover well.
If your mission is simply to get some cardio done, you shouldn’t waste your time obsessing over zone 2 versus zone 3 workouts. However, if you’re trying to run faster, you do need to first learn how to run slower. What happens at a truly easy, low-intensity effort is you can lay the aerobic infrastructure that eventually makes everything faster.
What do you think so far?
How to train to run faster
Now, here’s where a lot of runners who’ve heard the “slow down” message go sideways: They take everything easy and wonder why they’re still not improving. Low-intensity volume builds your aerobic base, but it doesn’t push your lactate threshold or teach your legs to turn over quickly. For that, you need real intensity.
Running economy—how efficiently your body uses oxygen at a given pace—is one of the strongest predictors of performance. I spent the last month testing and reviewing the Garmin Forerunner 970, and next month I’m adding the HRM-600 chest strap in order to properly test the “running economy” metric. Here are the workouts I’ll be doing to try to improve my running economy:
Threshold running. Threshold work (often called tempo running) teaches your body to sustain a comfortably hard effort. Twenty to forty minutes at this effort, once a week, is one of the highest-leverage things a recreational runner can do. It raises the pace at which lactate begins to accumulate, which is another way of saying it makes your “hard” feel easier over time.
Interval training. This forces your cardiovascular system to operate near its ceiling. Short, sharp intervals—think 400 to 1,200-meter repeats at a pace faster than your current 5K—improve VO2 max and reinforce good form under fatigue. These should feel genuinely difficult, and as such, they require real recovery. One interval workout a week is a solid start.
Strides or short accelerations. Strides are a great way to train your turnover speed. Adding four to six strides after an easy run, two or three times per week, is a low-risk, high-return habit to improve running form and eventually speed.
Remember to train smarter, not just harder
I know firsthand that recreational running culture has a complicated relationship with volume. Logging more miles carries a certain social currency, and of course, mileage does matter. But mileage added on top of chronic gray-zone training just adds more gray-zone training. If your 35-mile week is all moderate effort, jumping to 45 miles of moderate effort won’t break your plateau. In fact, it’ll deepen it, and probably bring you closer to injury. The question worth asking isn’t, “How many miles am I running?” but, “What is each of those miles actually doing?“
It’s true that around 80% of your runs should feel easy enough to talk in full sentences. But at least once a week, you should be pushing yourself, such as with threshold work or interval training. Add mileage gradually and only when the easy days actually feel easy. For our purposes here, intensity is the point, not quantity. Go truly easy when easy is what’s called for, and truly hard when the session demands it.