Activity Metrics: Work, Efficiency and Intensity Minutes
Understand mechanical work, output per heartbeat, relative heart rate and intensity-minute credit.
Learn
Understand the values behind your training. Each explanation documents the calculation used by EffortSignal, a worked example and the data it needs.
Aerobic Decoupling
Aerobic decoupling compares output per heartbeat in the first and second halves of suitable recordings.
ATL — Acute Training Load
ATL is the faster-moving average of daily cardiovascular TRIMP load.
CTL — Chronic Training Load
CTL is the slower-moving average of daily cardiovascular TRIMP load, shown as Fitness.
Next-day Easy-load Estimate
The easy-load estimate solves the product's ATL and CTL recurrences for an equal next updated state.
Estimated FTP from Cycling Power
eFTP is a constrained estimate from cycling power-duration evidence, separate from the configured FTP.
Training Monotony and Training Strain
These Dashboard summaries describe the distribution and amount of TRIMP over seven consecutive daily rows.
Planned Workout Load
Planned load estimates the authored structure. It does not run the completed-activity sensor formulas in advance.
Power Intensity
Power Intensity expresses Weighted Power relative to the applicable power threshold.
PSS, PI and familiar power metrics
How PSS, PI, Weighted Power and Power Variability correspond to TSS®, IF®, NP® and VI—and why EffortSignal uses different names for the same core formulas.
Power Variability
Power Variability compares Weighted Power with average timer-running power.
PSS — Power Stress Score
PSS combines timer duration with weighted power relative to the applicable FTP.
Readiness: Factors, Baselines and Coverage
Readiness combines baseline-relative HRV, resting heart rate, sleep and workload. It is a model with explicit missing-data gates.
How Training Load Works
Learn how EffortSignal turns recorded heart rate into daily TRIMP, ATL, CTL and TSB, including formulas, day boundaries, examples and data limits.
TRIMP — Training Impulse
TRIMP estimates cardiovascular training load from duration and relative heart rate.
TSB — Training Stress Balance
TSB, shown as Form, is the difference between chronic and acute load entering a day.
Your Usual Training Volume
The weekly usual range compares a completed week with eight immediately preceding complete weeks.
Weighted Power
Weighted Power gives variable power a fourth-power-weighted summary over complete 30-second windows.
Workload Ratio
The Dashboard workload ratio compares the current ATL with CTL from the same TRIMP history.
Training Zones and Effective Thresholds
Zones classify measured output or heart rate using the athlete settings applicable to the activity.