Built on the Banister fitness-fatigue model — the same science elite coaches use — Fitness Impact reads your training history and prescribes today's session against your real recovery state. Runs entirely on your iPhone. Never sells your data. No subscription.
On the App Store soon → Launching 2026 · in reviewEvery session you log feeds a dual-factor Banister model — the same framework used in elite sports science — to compute a per-muscle form score. The planner reads those scores and picks exercises that match your current readiness. Transparent math. Re-derivable.
Rate of Perceived Exertion is a first-class input. RPE 7 → add weight. RPE 9 → hold. RPE 10 → reduce. It's the autoregulation framework powerlifters and strength coaches trust — not reps-in-reserve buried in a weight-displacement proxy.
Your data lives on your iPhone and your personal iCloud. Optional Apple Health sync. No server, no account to create, no analytics, no advertising SDKs. You can export everything the app holds as JSON in two taps.
Most apps log your workouts.— the positioning, plainly
This one understands them.
The planner scores every available exercise as
muscleNeed × recoveryReadiness × goalAlignment × variety × balanceCorrection.
Recovery readiness comes from the Banister model
(τfitness=42d,
τfatigue=7d). Goal alignment
is your explicit emphasis boost. Balance correction
nudges toward the weaker side of push/pull,
upper/lower, and anterior/posterior pairs.
Then a greedy fill with saturation re-ranking prevents any single muscle from dominating the session. Your intensity mode — push, normal, light, deload — is computed from your form score, not guessed at.
Every step is visible in the in-app "How It Works" screen. Nothing proprietary. No black box.