Question 1

What is FTP and why does it matter?

Accepted Answer

FTP (Functional Threshold Power) is the maximum average power you can sustain for approximately one hour. It represents your aerobic ceiling — the boundary between sustainable and unsustainable effort. FTP is the cornerstone of structured cycling training because all power zones, race pacing, and workout intensities are derived from it. According to Allen & Coggan (2010), tracking FTP over time is one of the best ways to measure fitness progression.

Question 2

Which FTP test protocol is the most accurate?

Accepted Answer

The 20-minute test is considered the gold standard for self-testing because 20 minutes is long enough to tax your aerobic system without excessive anaerobic contribution. The 0.95 correction factor (Allen & Coggan, 2010) is well-validated. However, the ramp test is the most practical for indoor cycling and is used by Zwift, TrainerRoad, and Wahoo SYSTM. For best results, use the same protocol consistently so you can track changes over time.

Question 3

How often should I test my FTP?

Accepted Answer

Most coaches recommend retesting every 4-8 weeks, or at the start of each training block. Testing too frequently can be counterproductive — FTP changes take time. If you notice your training zones feel too easy or too hard, that's a sign to retest. Some platforms like TrainerRoad also auto-detect FTP changes from your training data.

Question 4

Can I estimate FTP without a formal test?

Accepted Answer

Yes, but with less accuracy. Some methods include: using your best recent 60-minute power from a race or hard ride, taking 95% of your best 20-minute power from any ride, or using ramp test equivalents on indoor trainers. TrainingPeaks can also estimate FTP from your power curve. However, a structured test in controlled conditions will always give the most reliable result.

Question 5

Why does the ramp test use a 0.75 factor instead of 0.95?

Accepted Answer

The ramp test measures your Maximum Aerobic Power (MAP), not your sustained power. MAP is significantly higher than FTP because the test includes a large anaerobic component at the end. The 0.75 factor converts MAP to an FTP estimate. This factor works well for most athletes but can be less accurate for those with unusual anaerobic capacities (very high or very low sprint power relative to endurance).

Question 6

What should I do after finding my FTP?

Accepted Answer

Once you know your FTP, use it to set your 7 power training zones (Coggan model). These zones guide every workout — from easy endurance rides (Zone 2, 56-75% FTP) to VO2max intervals (Zone 5, 106-120% FTP). You can also use your FTP to set race pacing targets for triathlon and cycling events. TrainingZones.io's Power Zones Calculator does all of this automatically — just enter your FTP and weight.

FTP Calculator — Estimate Your Functional Threshold Power

FTP Test Protocols — Complete Guide

Frequently Asked Questions