The world doesn't need another workout tracker. There are already great ones — Hevy for strength, Strava for cardio, Garmin and Apple Watch for data. They're excellent at what they do.
What's missing is the intelligence layer. The part that looks at your training history, understands exercise science, and creates a structured program that actually leads somewhere. That's what phase.fitness is.
We're an AI that creates programs for your favorite apps.
The name is the domain: phase.fitness, written in lower case with the dot and read “phase dot fitness”. It is an independent hybrid training planner at www.phase.fitness, and it is not affiliated with other apps or companies that use the word Phase in their name.
A single workout in isolation is almost meaningless. What matters is how workouts connect into a progressive sequence — building volume, shifting intensity, managing fatigue, and peaking at the right time. This is periodization, and it's the foundation of everything we do.
No plan survives contact with reality. Your body responds differently than expected, life gets in the way, some exercises work better than others. phase.fitness reads your actual performance and adjusts — weekly workload updates, automatic deloads, RPE-based progression. The program evolves with you.
Your training data lives in many places — Hevy or Liftosaur logs your sets, your watch records your runs and your heart rate, Intervals.icu aggregates your wellness. We pull all of this together and use it to make smarter decisions about your next training block.
phase.fitness isn't meant to be open all day. The ideal usage is a weekly check-in where the AI reviews your progress and prepares your next training block.
Import your latest workouts from Hevy, Liftosaur and Garmin. Wellness data flows in automatically from Intervals.icu.
The AI analyzes your performance, fatigue signals, HRV trends from Intervals.icu, and progress against your program goals — your Garmin activities too, if you allow it.
Adjust next week's training with one click. The AI modifies volume, intensity, and exercise selection based on your recovery.
Send updated routines to Hevy, Liftosaur or your Garmin watch, and cardio to Garmin or Intervals.icu. Open your favorite app and train.
The rest of the week? Train in Hevy, run with your watch, live your life. phase.fitness works in the background — it's your training intelligence, not your daily workout app.
We don't replace your tools — we make them smarter. Through our integrations, every app in your training stack gets the benefit of AI-powered periodization.
Intervals.icu forwards from there — Apple Watch · Suunto · COROS · Wahoo · Amazfit
Tick Post to Strava when you save a session and it goes to your feed. Nothing comes back: Strava's rules keep its data out of AI apps, and it can't take a planned workout.
No exercise catalogue out there has a tuck front lever. Those sessions play in phase.fitness's own player, and count in the program like the others.
Routines go to Hevy or Liftosaur and to Garmin, set by set — and what you log comes back.
Structured workouts go to Garmin and Intervals.icu with their intervals and targets.
Garmin directly. Apple Watch, Suunto, COROS, Wahoo and Amazfit through Intervals.icu.
Training should be structured, not random. Science-based periodization beats motivation every time.
AI should augment coaches, not replace them. We automate the programming — you bring the effort.
Your data belongs in the apps you already use. We're the brain, not the tracker.
Recovery is not optional. Deloads, fatigue management, and wellness monitoring are first-class features.
Transparency matters. We clearly attribute features to the platforms that power them. Garmin takes our workouts directly; other devices get them through Intervals.icu.
Create your first AI-powered, periodized training program in minutes.