I Was Wrong About Junk Miles (A Power Meter Proved It)

I used to think “junk miles” was just bravado.

You know, those runners who brag about getting out there 7 days a week? I thought they were just grinding themselves into the ground. Just forcing it.

And I couldn’t back up runs day after day, so I must have been right…

Then I started using a power meter.

The number that embarrassed me

I saw that other runners were doing their easy runs at less than 75% of threshold power. It was embarrassing, but I noticed I couldn’t actually run that slow. My “easy” runs were actually low-end tempo.

Running slow is a skill.

And I didn’t have it.

My junk miles weren’t junk because easy running is pointless

They were junk because they were too hard.

Which meant my speed sessions weren’t fast enough, because I was too tired to hit them properly.

So I spent 6 weeks learning how to run slow. Like, actually slowly. It was a hit to the ego. But it changed everything.

The quality of your speedwork is determined by the quality of your easy runs

If you do your easy work too hard, you’re not actually recovering. You’re just stacking fatigue. And then your speed work suffers for it.

So many experienced marathon runners are stuck in a plateau because they’re running their easy runs too hard, and they can’t see it.

Without power data, you can’t tell if you’re truly recovering or just grinding yourself down at 85% day after day. That’s why adding more volume leads to injury instead of improvement.

What changed when I finally dialled it in

When I finally got my easy runs right, I unlocked the ability to back up 7 or even 8 runs in a week without falling apart.

I could absorb my hard sessions. I could increase volume without a disproportionate increase in stress.

I could actually train like the runner I wanted to be.

Easy days prevent injuries. Hard days create fitness. Both are non-negotiable.

Where to start

If you’re stuck guessing whether your “easy” days are actually easy, that’s the first thing to fix: before you add volume, before you add intensity. (If you want the longer breakdown of why this trips up so many marathon runners, read why your easy runs are probably too hard.)

I put together a free 5-step guide that shows you how to convert any training plan into a power-based plan, so your easy days are actually easy and your hard days are actually hard. Grab it here and start training with the number that doesn’t lie.