What is Xert?
Xert's argument is that the FTP test is redundant paperwork: the hard rides you already do contain the same information, so it goes and takes it. It reads every activity with power data, hunts for maximal efforts, and extracts a three-number Fitness Signature — Threshold Power, High Intensity Energy (the finite reserve you spend above threshold), and Peak Power. Those three feed the number Xert is really built around: Maximal Power Available, "a measurement of the maximal power that can be produced by an athlete for a given exercise, factoring in fatigue." MPA is computed second by second. Ride hard early and it sags; sit up and it climbs back. When your actual power crosses the MPA line — Xert's guidance is roughly five seconds above it — that's a breakthrough, meaning the signature was too conservative, and Xert raises it on the spot rather than waiting for you to book a test.
Strava is both an input and an output here. Under Sync > Strava there are two independent switches. One pulls activities from Strava into Xert automatically, with a custom date range for backfilling history — Strava's API lets Xert reach about three years back, and Xert asks for at least three months before it trusts its own analysis. The other pushes activities recorded in Xert's own apps out to Strava, and can write a training summary (XSS, Difficulty Score, estimated fat and carb use) plus a Forecast AI report with an MPA chart into the Strava activity itself.
The catch on that second switch is worth knowing before you wire anything up: the reports only appear if the ride reaches Xert first and Xert forwards it to Strava. If your Garmin, Wahoo or Zwift account is already pushing straight to Strava, Xert sees a duplicate and the reports don't post.
Key Features
A Fitness Signature that updates itself
Threshold Power, High Intensity Energy and Peak Power, re-derived from your best efforts as you produce them. Xert calls it a fitness fingerprint, and the whole no-testing pitch rests on it: your threshold number moves because of a ride you actually did, not a protocol you scheduled.
MPA in real time, on the head unit
The Garmin Connect IQ player and the Xert EBC mobile apps draw your live power against your live MPA, so you can see how much is left before the point of failure instead of guessing. This is the part that's hard to get anywhere else — most platforms only tell you about fatigue after the fact.
Breakthroughs, graded
A breakthrough is scored by how much of the signature it moved: gold when all three values improve, silver for two, bronze for one. Efforts that get close without crossing MPA are flagged as near-breakthroughs — Xert users call them fakethroughs.
Training Status and Form
Form is a five-state readout of how recovered you are: Very Fresh (green), Fresh (blue), Tired (yellow), Very Tired (red), and Detraining (brown) after seven days with no recorded activity. It's not decorative — the advisor caps what it will recommend, so a tired status limits you to workouts of difficulty 2.5 or below. Training Status is the separate ladder your accumulated Training Load sits on, from Untrained below 25 through Recreational, Trained, Competitive and Elite to Pro Level above 150.
Focus
Rather than label a ride "tempo", Xert converts it to a Focus Duration on your power curve and names the rider it trained you toward — Breakaway Specialist at five minutes, GC Specialist at 8:43. A Specificity Rating says how tightly the work clustered around that focus power, from Pure at 100% down through Mixed and Polar.
Forecast AI
Set a program type and a target date and Forecast AI lays out a day-by-day forecast to it: expected Low, High and Peak XSS, training loads, training status, and where your Fitness Signature should end up. Change your availability and Adapt Forecast recalculates the whole thing.
Smart workouts on most of the devices you own
SMART intervals chase a target MPA rather than fixed watts, so the effort scales to the fitness you have on that day. They play through the Garmin Connect IQ Workout Player and Xert EBC on Android and iOS; connecting a Wahoo account sends your scheduled workout to a Bolt, Roam or RIVA and the Wahoo app automatically; and workouts export as ZWO, ERG or TCX for Zwift and friends. One honest caveat: Xert EBC for Android was last updated on Google Play in July 2025, while the iOS build on the App Store is still version 3.2.1 from November 2021.
Who It's For
- Cyclists with a power meter who will happily do the hard ride but not the scheduled test
- Racers with a date circled who want a plan that projects forward to it and rebuilds when the week falls apart
- Riders who race and ride unstructured, where knowing how much is left right now beats a post-ride TSS number
- Strava-first cyclists who want the analysis to come back and live on the Strava activity
