ThreeByEight: Training Planner

About ThreeByEight: Training Planner

ThreeByEight plans your training — and shows its work.

Most training apps hand you a number and ask for faith. ThreeByEight shows the reasoning behind every target: what you lifted last time, what the rep range calls for, and why today's suggestion is what it is.

No AI, no black box. Every target comes from transparent progression rules applied to your own logged work — the same arithmetic a good coach would show you on paper. Nothing guesses, nothing hallucinates a workout, and the answer to "why this weight?" is always on screen.

PLAN • Build multi-week training blocks: pick your days, choose your lifts, set your rep ranges. • Cardio belongs in the plan, not a separate app: schedule cardio blocks right alongside your lifts, and they count — in your day, your week, and your history. • The week grid shows the whole block at a glance — what's done, what's planned, and where today sits.

TRAIN • A session view built for the gym floor: log sets fast, with last time's performance right next to today's target. • Double progression that explains itself — load and reps move when your logged work earns it, and the app tells you why. • A rest timer that lives in your notification shade — when rest is up, one tap puts you back in your session. • Plate math on tap: see exactly what to put on the bar. • Calisthenics done right: weighted and unweighted variations tracked separately, with reps-only progression where load isn't the point.

TRACK • Honest strength trends — estimated one-rep max charted from the sets you actually logged, not smoothed into flattery. • Bodyweight logging with your history where you expect it. • Writes finished workouts — lifts and cardio alike — and bodyweight to Health Connect, so your training lands in your own health store. Write-only by design: ThreeByEight never asks to read your health data.

WORKS WHERE YOU TRAIN • Offline-first: log an entire session in a concrete basement. It syncs when you're back in signal.

ThreeByEight runs on a subscription, with a 14-day free trial. Your data stays yours: delete your account and everything in it any time, from the app or the web.

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