The uncomfortable truth about effort
If you've ever glanced at your pace mid-run and quietly sped up because it felt embarrassingly slow, you're in good company. Most recreational runners spend the vast majority of their training in a sort of murky middle zone — not comfortable enough to be truly easy, not hard enough to be genuinely tough. It feels productive. It often isn't.
The result is a pattern coaches sometimes call "junk miles" — runs that are too taxing to fully recover from, but not demanding enough to drive meaningful adaptation. You end up tired and stagnant at the same time, which is a deeply unsatisfying combination.
The fix, slightly maddeningly, is to run slower.
What's actually happening when you go easy
Your body has two main energy systems, and they respond to training in very different ways. When you run at a genuinely easy pace — one where you could hold a full conversation without gasping — you're predominantly working your aerobic system. This is where the long-term magic happens.
Easy running builds the density of mitochondria in your muscle cells (these are the tiny engines that convert oxygen into usable energy). It improves the efficiency of your heart, strengthens the connective tissue around your joints, and teaches your body to use fat as fuel — which matters enormously in longer efforts when carbohydrate stores run thin.
None of this happens quickly. And none of it feels particularly dramatic on the day. But over weeks and months, a well-developed aerobic base is what allows you to run faster, for longer, with less effort. The easy days aren't filler. They're the foundation.
Why we find it so hard to actually go easy
Part of the problem is psychological. Running slowly in public can feel exposing, especially if you've absorbed the idea that more effort equals more progress. There's also the simple fact that easy running, by definition, doesn't feel like very much — and we're conditioned to equate a sense of struggle with a sense of worth.
The other issue is that "easy" is genuinely difficult to calibrate. What counts as easy depends on your current fitness, how well you slept, what you ate, how stressed you are, and a dozen other variables that shift from day to day. A pace that felt leisurely last Tuesday might feel laboured on a warm Thursday after a bad night's sleep.
This is why many coaches recommend training by feel — using perceived effort and, where available, heart rate — rather than chasing a fixed pace on every run. Your body knows what easy feels like. The trick is learning to trust that signal rather than override it.
The 80/20 principle (and why most of us do it backwards)
Research into elite endurance athletes consistently finds that the best performers spend roughly 80% of their training time at genuinely low intensity, and only about 20% at moderate-to-high intensity. This distribution is often called polarised training, and it produces better outcomes than spending most of your time in the middle.
Most recreational runners, left to their own devices, tend to flip this around. They run medium-hard most days because it feels like the responsible thing to do, and then wonder why they plateau or pick up niggles.
Shifting towards an 80/20 split doesn't mean suddenly doing less. It means being more deliberate: making your easy days properly easy, so your hard days can be genuinely hard. The contrast is the point.
How Will Powered helps you find your easy
One of the things Will Powered pays close attention to is whether the effort you're putting in on a given day actually matches what your body can handle. The daily check-in asks how you're feeling before you train — not to gatekeep your run, but to build a picture of where you are right now, on this particular day.
If you've flagged that you're tired, a bit flat, or coming off a tough week, Will Powered uses that context to shape what it suggests. That might mean nudging a planned tempo run towards something gentler, or simply noting that today is a day to keep the effort dialled back. Over time, those adjustments add up — protecting you from accumulating too much fatigue while still keeping the training moving forward.
Easy days aren't a compromise. They're part of the plan.
A practical test for easy
Not sure if your easy runs are actually easy? Try the talk test. If you can speak in full sentences — not just gasp individual words — without having to pause and recover, you're in the right zone. If you'd rather not talk, you're probably going a bit too hard.
Alternatively, if you use a heart rate monitor, aim to keep your heart rate in the lower end of your aerobic range. For most people, this works out somewhere around 60–70% of maximum heart rate, though that varies with age and fitness. The number matters less than the principle: it should feel sustainable, almost boring, for the whole run.
Give it a few weeks. The pace will likely start to creep up even as the effort stays low — and that's the aerobic base doing exactly what it's supposed to do.
Slow down to go further
The counterintuitive thing about easy running is that it requires a bit of confidence. You have to trust the process when the process doesn't feel impressive in the moment. But the runners who make consistent, sustainable progress over months and years tend to be the ones who've made their peace with going slow — regularly, deliberately, and without apology.
Your easy days are doing more than you think.
Try Will Powered free and see how daily check-ins and smart adaptation can help you train smarter — at every pace.