THE
FIREHOUSE STRENGTH & CONDITIONING
FUNCTIONAL THRESHOLD POWER
CALCULATOR

Take the Test

This field test records 20-minute performance on one machine and provides starting points for training. It does not measure blood lactate, VO₂max, or fitness for duty.

  1. Choose a machine that reports average watts. Keep the same model and settings for repeat tests.
  2. Warm up for 10–15 minutes.
  3. Complete a hard, evenly paced 20-minute effort. Avoid an opening sprint that prevents a steady finish.
  4. Record average power for the full 20 minutes. The existing calculator also accepts average heart rate from minutes 3–20 as a coaching reference.
  5. Optionally enter body weight for estimated watts per kilogram. Keep the protocols separate: this is a 20-minute test. Do not enter a six-minute AirBike result here. Use the six-minute AirBike test for that protocol.

Get your personalized zones

Enter your recorded values and select Calculate. The outputs are estimates for planning training, not laboratory measurements.

  • Power: the calculator multiplies 20-minute average watts by 0.95. For example, 200 W produces a 190 W estimate. This cycling-derived convention is also applied to the other machines in this tool; that does not establish its validity for every modality or individual.
  • Heart rate: the calculator uses your minutes 3–20 average directly as its zone reference. This is an FHS&C coaching convention, not a verified lactate threshold and not the published Joe Friel test protocol.
  • W/kg: estimated power divided by body mass in kilograms. Compare repeated results on the same machine and setup.
  • Zones: percentage-based starting targets. Adjust using workout response and coaching judgment; do not transfer watts or heart-rate targets unchanged between machines.

Method sources and limits

TrainingPeaks explains the 95% cycling power estimate. Joe Friel's 2011 heart-rate field test uses the final 20 minutes of a 30-minute effort; his guide revised in September 2025 uses 95% of the full 20-minute average for functional threshold heart rate. Neither matches the minutes 3–20 input used here. The calculator's existing formulas have been retained and their limitations made explicit.

Put the result to work

Read the FTP training guide, explore the firefighter training program, or ask a coaching question. Method explanation reviewed October 4, 2026. Coaching framework: Eric Haskins, Firehouse Strength & Conditioning.

Power + Heart-Rate Training Estimates

Pick your erg, plug in your 20-min test numbers, and get starting targets for training.
The same 0.95 factor is applied to each erg; validity is not established across all modalities.
Full 20:00 average power.
Exclude the first 2 minutes.
Used only for W/kg.
Method: Estimated power = 0.95 × 20-min average watts. HR reference = average HR from minutes 3–20 (FHS&C convention, not a measured lactate threshold or the published Friel test). Zone percentages are coaching starting points; see methods above.
Enter values and hit Calculate to see estimated power, HR reference, W/kg, and suggested zones.

Disclaimer:

The Firehouse S&C FTP Calculator is a training tool, not a medical test.

Always consult with a physician or qualified professional before starting new fitness testing or programs.

Use this tool to sharpen the edge and be precise with your training so you never miss the mark.

Firefighting is dangerous — Train Hard. Train Often. Train Like a Firefighter.