The Power-Based 20 minute Field Test
Frank Overton
A 20 minute power-based field test is a simple, repeatable way to track your cycling fitness. The test is straightforward and will help you see clear improvement from your training over time.
Below is our latest podcast episode explaining why the 20-minute field test works so well, how to perform it, and when to schedule it into your training plan. Listen and learn!
The 20-minute field test is our preferred method of testing because it strikes the perfect balance between simplicity, accuracy, and practicality. All you need is a power meter and a willingness to push yourself to the limit for 20 minutes. Unlike shorter tests that can overestimate your Functional Threshold Power (FTP), or longer ones that can be both daunting and less repeatable, the 20-minute duration offers a “Goldilocks” approach that is neither too short nor too long.
The 20 minute test also more closely mirrors the physiological demands you’ll encounter in real-world time trials or hill climbs than automated ramp tests do, providing data that is comparable to competition. By sticking to a consistent protocol over time, you can track your progress with confidence and make informed decisions to optimize your training.
The training plans & phase in CoachCat prescribe a 20-minute field test at the end of a recovery week or when you’re fresh, ensuring fatigue does not confound the test results.
Calibrate your power meter and check your bike to avoid any mid-test malfunctions. If you’re testing outdoors, pick a safe, uninterrupted stretch of road free from traffic and stoplights; if you’re indoors, set up on a stable trainer with consistent conditions (cool down the room and have a strong fan!)
To learn more about performing a test indoors on Zwift, read our training tip here.
Use the warm-up, provided in the CoachCat 20 minute Field Test Warm Up where you gradually build intensity but not too much 👇
Begin the test conservatively - the first 2 minutes should feel easy. Use previous data or threshold workouts to not go out too hard. Minutes 5-10 should be challenging and the last 5 minutes should be as hard as you can go - enough that you need to lay down on the side of the road or room afterwards.
We recommend two field tests per year coupled with your competition data.
Upon completion, CoachCat will auto detect your FTP and set your zones only if you set a higher FTP. If not, use your 20 minute xPower minus 5%. Enter that number [plus your Average HR] into the FasCat App under Profile > Training Zones.
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Road Racing Intervals
- Increase your functional and race-specific power output
- Includes Sweet Spot, VO2, Anaerobic, Threshold
Road Race In-Season
- Weekend racing and group rides with weekday training and recovery
- anaerobic efforts like criss cross, Over/Unders Sweet Spot, Threshold
Foundation : 3 Weeks
- Perfect for all cyclists beginning off season training
- Raise your CTL and the all-important muscle tension intervals
Phil Gaimon's Strava PR Plan
- Perfect Plan for Those with Less Training Time, starts at 15 minutes per day
- VO2's, 1 minuters, Tabatas, threshold, suprathreshold, and even Sweet Spot
