Afitpilot®
← Back to Glossary
Intensity & Effort

Effort Delta

Also known as: RPE Deviation, Effort Mismatch

The difference between your actual session RPE and the prescribed target RPE. A positive delta means the session felt harder than planned; negative means easier.

Formula

Effort Delta = Actual Session RPE - Target Session RPE

Example

Target RPE: 7.0. Actual RPE: 7.8. Effort Delta = +0.8 (amber flag — slightly harder than planned).

How Afitpilot Uses This

Effort delta is one of three comparison domains (alongside volume and load) in our Target vs. Actual analysis. We use threshold-based color coding: neutral (< 0.7), amber (0.7-1.2), red (> 1.2). A consistently positive effort delta over multiple sessions ("effort creep") may indicate accumulated fatigue, poor recovery, or prescriptions that need adjustment.

What your effort delta is telling you

Who / ContextValueNote
Delta < +0.7On trackNormal session-to-session variation
Delta +0.7 to +1.2Amber — monitorCould be a bad day or early fatigue
Delta > +1.2 (one session)Red — don't panicSingle readings are noisy
Delta > +0.5 for 3+ sessionsOvertraining signalRecovery isn't keeping up — consider deload
Active aging (60+)Wider swings are normalTrack the trend, not individual sessions

Known Limitations

  • •The thresholds (0.7 / 1.2) are based on general coaching heuristics, not individualized to the athlete. An experienced lifter may have tighter natural RPE variance than a beginner.
  • •A single session's effort delta is noisy. The trend over 4-6 sessions is far more meaningful than any individual reading.

What We're Improving

  • Future

    Individualized Alert Thresholds

    Replace static delta thresholds (0.7 / 1.2 RPE, 10% / 25% volume/load) with personalized thresholds derived from each athlete's historical variance.

  • Shipped

    Universal Internal-Load Currency (sRPE → AU)

    Move from tonnage-as-primary to a universal session-load number using Foster's sRPE × duration method. AU is now the headline load metric on every session card and rolls up weekly with a 3-bucket modality split (Strength / Endurance / Mixed). Tonnage stays visible as a strength-specific secondary.

Science Context

Monitoring the gap between prescribed and perceived intensity is a core principle of autoregulated training (Mann et al., 2010). Chronic effort overshoot is associated with non-functional overreaching and may precede performance plateaus.