Why Easy Running
Is the Real Work

Most runners are running too hard, most of the time. Here is what the science says, what your body is telling you, and why slowing down might be the most important thing you do this year.

I have coached a lot of runners. And there is one pattern I see consistently, regardless of experience level, fitness, or how long someone has been running: almost everyone runs their easy sessions too hard.

Not by a little. Often by quite a lot. And they do not know it, because the pace they are running at feels comfortable. It no longer feels hard. It is their default, and over time that default has started to feel like easy. It is not.

This matters enormously for how your fitness develops, how quickly you recover between sessions, how you perform on race day, and how long your body stays healthy over a season. Understanding what easy actually is, and why it produces results that harder work cannot, is one of the most valuable things you can take into your training.

The Aerobic System: What Is Actually Being Built

When you run at a genuinely low effort, an extensive set of physiological adaptations begin to accumulate. These are not minor or preparatory. They are the foundation that every other training quality sits on top of.

None of these adaptations require hard effort. They require time at low intensity. Going too hard too soon does not accelerate this process. It actively interferes with it, because the physiological demands of hard running suppress the cellular signalling pathways that drive aerobic adaptation. This is one of the most counterintuitive truths in exercise science, and most recreational runners never hear it clearly.

What Easy Actually Feels Like

Easy running has a specific feel. It is not just "not sprinting." It sits within a defined effort range, and most runners are above that range without realising it. The signals are available to you without any technology.

On the RPE scale of 1 to 10, easy sits at 3 to 5. RPE 3 is almost too slow: quiet breathing, fresh legs, very little sensation of working. RPE 4 is the sweet spot: clearly running, mild warmth, nasal breathing throughout. RPE 5 is the upper ceiling: aware of the effort, conversation still comfortable. Aim for 4. Do not live at 5.

The Comfortable Hard Trap

There is a pace that most runners discover over time. A pace that used to feel hard, then moderate, and now feels comfortable. They call it their easy pace. They use it for recovery runs, for long slow sessions, for the days when they are meant to go easy.

The problem is that comfortable is not a physiological category. Adapted to is not the same as easy. A pace can feel entirely familiar and still sit above your aerobic threshold. This is the grey zone: too fast to drive aerobic base adaptations effectively, too slow to create meaningful speed or lactate threshold adaptation. You are working hard enough to accumulate fatigue without delivering the training stimulus that produces results.

Research on elite endurance athletes consistently shows that the highest-performing runners spend around 80 percent of their training time at genuinely low intensities, with the remaining 20 percent at high intensity with clear purpose.¹ Most recreational runners invert this accidentally, spending the majority of their time in the grey zone. The result is chronic low-level fatigue, plateaued performance, and a higher injury rate than either end of the spectrum would produce.

The Mental Work of Going Slow

Understanding the science does not automatically make easy running easy to do. There is a psychological resistance to slowing down that most runners have to work through, and it is worth naming it directly rather than pretending it is not there.

Part of it is ego. Running is visible. Pace is measurable. Slowing down can feel like underperforming, even when the data tells a completely different story. The story you tell yourself about your pace is not the same as the physiology of your pace.

Part of it is impatience. The aerobic base builds slowly. You do not feel fitter after one easy run, or five. The adaptations are cellular and invisible. But six to eight weeks of consistently easy training produces changes in mitochondrial density, capillary networks, and fat oxidation that are measurable and significant. The results are real. They are delayed, not absent.

The mental work of easy running is learning to trust a process before you can see the result. That is harder than running hard. It requires more self-awareness, more patience, and more willingness to feel like you are not doing enough when you actually are.

Why This Matters Especially on Trail

Trail running adds a layer of complexity that road running does not have. The terrain varies constantly. Heart rate fluctuates with gradient. A climb that sits at RPE 4 on flat ground will push you to RPE 7 on a steep ascent without any change in perceived leg effort. Pace becomes almost meaningless as an effort guide on variable terrain.

This means the breath test and the talk test become your primary tools. They are terrain-agnostic. On a climb, if you lose nasal breathing, slow down or walk. Walking uphill to keep effort in the easy zone is not a compromise. On trail, it is smart training. It protects your aerobic base work and teaches you to manage effort across changing terrain, which is exactly the skill that separates strong trail runners from those who blow up on race day.

Easy running on trail is also where you learn the surface. Where your feet begin to read terrain naturally, picking lines, responding to ground feedback without having to think about it consciously. None of that learning happens when you are managing high effort. It happens in the spaciousness of easy running, when your mind has capacity to take in the environment around you.

I have run across some of the most demanding terrain on the planet. And the training principle that has held constant across all of it is this: the quality of your base determines the ceiling of your performance. Not your threshold sessions. Not your long runs. Your base.

This week, experiment with genuinely going easy. Not as a concession. As a strategy. Notice what it feels like. Notice whether your body starts to tell you things it was too busy to say when you were running hard. The trail has a lot to offer at a slower pace. Let it.