What is RPE?

What is RPE?

RPE = Rating of Perceived Exertion.

It’s simply how hard the run feels to you in the moment—based on breathing, muscle strain, and how sustainable the effort feels. It’s not a sensor metric.

Why PaceAdapt uses RPE for v1

Heart rate and pace are useful data, but they’re unreliable as live targets for many runners because they’re affected by:

• heat / humidity

• hills / wind

• sleep / stress

• hydration / caffeine

• HR lag and drift

RPE doesn’t fight those realities—it incorporates them automatically.

The PaceAdapt effort bands (simple)

Easy

• You can talk in full sentences

• Breathing is calm, you feel like you could keep going for a long time

• This is where most weekly mileage should live

Steady

• You can talk in short phrases

• Controlled effort, focused but sustainable

• Feels “purposeful” but not desperate

Hard

• You can manage single words

• Clearly challenging and limited-duration

• Used sparingly and intentionally

Why this matters

Most runners improve fastest when:

• Easy days are genuinely easy

• Hard days are deliberate and limited

• Training is consistent week to week

Effort-led running is the easiest way to get that right without watch-chasing.

FAQ

Isn’t RPE subjective?

Yes—and that’s why it works. It captures the real cost of the run on that day.

Does PaceAdapt ignore heart rate?

No. HR is used after the run to understand your week and adjust next week. It’s not used to police you mid-run.