Plankan: Plank Trainer

Plankan takes you from wherever you are today to five 2-minute front planks in one session. There is no generated plan and nothing to configure. The whole program is one fixed ladder of reps × seconds. You do the next step. If you finish it, you move on. If you don't, you do it again. YOUR FIRST HOLD PLACES YOU Hold a plank for as long as you can. That one number puts you on the right rung — about 65–72% of your max — so you start where you actually are instead of at week one of someone else's plan. Already know your max, or timed it without the phone? Type it in instead. ADD A REP, THEN ADD TIME Add a rep until the level runs out, then the hold gets longer and the reps reset. This is double progression, and it's what the core-endurance research prescribes: increase the repetitions rather than the duration of the holds. It's also why the goal is five 2-minute holds rather than one ever-longer grind — repeated quality holds beat a single marathon one. EVERY LEVEL ENDS IN A MAX A max hold can't be failed. It charts your progress against the 2-minute line, and if it's strong enough it skips you past rungs you've already outgrown. FAILING A STEP COSTS NOTHING Miss a step and you just repeat it. Unlimited, no penalty, no streak to break. Each step is its own test, so there is nothing else to design. A TIMER YOU CAN READ FROM THE FLOOR The clock is a line, not a ring. A plank is the one exercise where nothing moves, so the timer contracts from both ends toward the centre as the hold drains and expands back out while you rest. Monospaced digits hold their width as they tick down. Work is stark white with no colour at all, because enduring a hold is not a celebratory moment — colour is reserved, so slate always means recover and brass always means progress. HAPTICS CARRY THE SESSION You can't see the screen mid-hold. Ticks escalate into every transition, and every transition lands harder than any tick, so the two can never be confused. Passing your best gets its own pulse. 12 levels. 54 steps. One rung a session, roughly a level a week. NO ACCOUNT, NO ADS, NO SUBSCRIPTION Plankan works entirely offline and collects nothing. There is no sign-up, no tracking and no upload. Your progress lives on your phone and nowhere else. Plankan is a training timer, not medical advice. If a plank hurts, stop.