Estimated 1RM — Docs

Metric’s estimated 1RM (e1RM) is your predicted one-rep max for a given exercise, calculated from sub-maximal sets. No actual 1RM testing required.

For most lifters and most use cases, e1RM is safer than true 1RM testing (no max attempts), more frequent (every working set updates it), and more sensitive (catches small changes between formal test days).

How it’s calculated

Two inputs:

Your load-velocity profile for the exercise — the relationship between load and bar speed for you on this lift.
The current set’s data — load and mean velocity of recent reps.

Metric extrapolates from the load-velocity line to find the load at which your mean velocity would drop to a 1RM threshold (typically around 0.15 m/s for compound lifts, lift-specific in practice).

After 5–10 working sets across a load range, the profile is robust enough that e1RM updates between sessions reflect real changes, not noise.

Where you see it

Set summary, when a set materially changes the estimate.
Performance charts, as a strength trend line over time.
Personal records, tracked per exercise.
Home screen, on the dashboard for top exercises.

Accuracy

Validated against actual 1RM testing — see the studies at /research. Typical accuracy: ±2.5–5% of true 1RM for compound lifts in lifters with a robust profile.

Less accurate when:

The profile is built from few sets.
The load range trained is narrow (only ever 70–80%).
The exercise has unusual velocity characteristics (deadlift e1RM tends to be slightly less accurate than squat or bench).

Using e1RM in programming

Picking working loads. Programme calls for 82% × 5? Use today’s e1RM × 0.82. The working load adapts to readiness automatically.

Tracking progress. Plot e1RM over time. If trending up across a block, the programme is working.

Avoiding test days. True 1RM testing costs fatigue, injury risk, and time. e1RM tests every session at zero extra cost.

When to do an actual 1RM test

Competition prep — you need real attempts.
Long absence from heavy work — if you’ve trained only at moderate loads for months, e1RM extrapolations are less reliable. A heavy single recalibrates.

What degrades e1RM accuracy

Bad bar speed data from poor camera setup.
Profile built from one rep range only.
Equipment changes between sessions.
Reps with tracking glitches polluting the working set.

e1RM per exercise

Each exercise has its own e1RM. Squat e1RM doesn’t apply to bench, even if you train them in the same session. Variations of the same lift (high-bar vs low-bar squat, front squat, SSB squat) get separate profiles too.

Coach view

Coaches see athlete e1RMs on the team leaderboard and in individual profiles. Useful for percentage-based programming that adapts per athlete.

How long the profile takes to build

5–10 working sets across a meaningful load range gives a good initial profile. Full robustness comes after 4–6 weeks of consistent training on the lift.