It’s common to run PR efforts and tests like VO₂max pace, AeT (Aerobic Threshold), and Critical Speed in carbon-plated shoes. Those shoes can make you faster at the same effort, which means your test results (and therefore your thresholds) may reflect “carbon-shoe speed”.
In day-to-day training, many runners use regular trainers, and paces can feel tougher than expected. That’s normal — and REN is built to handle it.
1) Adjust thresholds manually if they don’t match your reality
If you feel your current thresholds are inaccurate (for example, set on an unusually great day, a carbon-shoe test, or an extreme outlier), you can edit them manually:
Go to Settings → Thresholds
Update the value(s) you want to change
This is the quickest way to align REN with how you actually train most weeks.
2) Workouts are built with pace ranges (you don’t have to hit one exact number)
REN workouts are intentionally based on pace ranges, not a single target pace:
Most workouts use ranges of around 10 seconds
Easy runs use even wider ranges, often around 20 seconds
Why? Because shoe type is only one variable. Weather, fatigue, terrain, fueling, stress, and sleep can all shift your pace on a given day. We don’t expect you to run like a robot.
3) Intervals are usually set slightly below the thresholds on purpose
Especially for longer AeT and Critical Speed intervals, REN typically targets paces just below your threshold.
That’s intentional:
You still get high-quality work
Without pushing you into “overcooked” territory
Which helps you train consistently and recover well
Practical tips for carbon-shoe tests vs. trainer workouts
If workouts consistently feel too hard in trainers, lower the relevant threshold slightly (e.g., AeT or Critical Speed).
If only certain days feel off, stick to the range and run by effort—that’s exactly what the range is for.
Save carbon shoes for key sessions or races if you want, but it’s totally fine to do most training in trainers.
If you tell me which test you used (VO₂max pace, AeT, or Critical Speed) and what feels “off” in training, I can suggest which threshold is most likely the one to adjust.