Integrations
phase.fitness plans your training and runs it — and then gets out of the way, into the app you already log in and onto the watch you already wear. It sends workouts to Garmin, pushes a program to Hevy or Liftosaur, and writes endurance sessions to Intervals.icu. Here is exactly what travels, which way, and where it doesn't need to.
Where your sessions travel
All three are written by the AI into your phases, and all three can be run in the built-in player — on a phone at the rack, or a laptop on the kitchen table. What follows is the second half of the journey: where a session also goes once it exists.
| Session | GarminWatch | Intervals.icuEndurance | HevyStrength | LiftosaurStrength |
|---|---|---|---|---|
Strength Barbell, dumbbell and machine work, periodized across your phases. | Sent and returned Sets and reps on the watch | Comes back only Counted in your load | Sent and returned | Sent and returned |
Cardio Structured intervals with heart-rate and power targets. | Sent and returned Six sports by name, the rest as generic cardio | Sent and returned Intervals and zones intact | Strength apps — your cardio goes to Garmin or Intervals instead | |
Calisthenics Skill work toward a movement: its own catalogue, roadmaps, holds and progressions. | Built-in player — no exercise catalogue out there has a tuck front lever, so there is nothing to send | |||
Cardio on your watch
These arrive with their own sport, so the watch counts laps and zones properly: Running, Cycling, Swimming, Rowing, Walking, Hiking. The rest — triathlon, kayaking, cross-country skiing, mountaineering — arrive as a generic cardio workout: the session is there, the label is less precise.
Why a front lever has nowhere to go
A front lever isn’t a movement Hevy or Garmin know about — their exercise sets are built around barbells and heart rates. So a calisthenics session has nowhere to be sent, and doesn’t need one: the player walks you through the holds and the progressions, and the session counts in your program exactly like the others. The roadmap for the skill is the thing doing the work, and it lives here.
Data coming in
Everything below lands in one place, and that one place is what the AI reads when it writes your next block. Garmin is the one you decide on: your activities always mark the plan done, and reach the AI only if you allow it.
| Source | Direction | What it brings |
|---|---|---|
| Garmin | Comes back only |
Activities only: no sleep, HRV or body battery. The AI uses them only if you allow it. |
| Intervals.icu | Comes back only |
Also the way Apple Health data reaches phase.fitness. |
| Hevy | Comes back only |
|
| Liftosaur | Comes back only |
Mutually exclusive with Hevy — you connect one or the other. |
Sessions going out to Strava
- The sessions you finish in phase.fitness, on your Strava feed
- Strength, cardio and calisthenics, with your sets in the description
Only the sessions you choose to post. phase.fitness doesn't import from Strava: since June 2026 Strava's rules don't let apps use your Strava data in AI. Your runs and rides reach your plan from Garmin or Intervals.icu.
Connect what you already use
You don't have to change app to train with a real program. Connect one, or all of them, and phase.fitness works around what you already do.
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