It runs on your phone.
There is no account, no server and no model behind the plan. The engine is a deterministic set of rules that runs on the device, so the same answers always produce the same week. Nothing about your training leaves the phone to build it.
That is a design choice with a trade-off worth naming: you get a plan instantly and offline, and you do not get anything that learns from other players.
Safety runs before the plan.
Before a single exercise is chosen, the screen runs. Pain rated 5 or higher out of ten, or any red flag — swelling, numbness or tingling, night pain, recent surgery, or a doctor telling you not to train — stops plan generation entirely. You get a referral message, not a lighter week.
CourtFit cannot evaluate an injury, and it does not try to. It refuses instead.
It schedules around your tennis.
Your gym days are placed against your court days, not next to them. The heavy-leg day goes on the gym day furthest from your next tennis session. A gym day that lands the day before tennis becomes a primer: lower-body sets are halved and every jump is removed, so you arrive fresh instead of flattened.
Tell the app you have a match in the next 24 hours and it rebuilds the week on the spot with reduced lower-body volume and no jumping.
Pain changes the day twice.
Flagging a joint does two things, not one. Movements that provoke it are removed. And the light stability work assigned to that same area is kept and moved to the front of the session, where it is actually done rather than skipped at the end.
Flag the elbow and heavy gripping comes out specifically. If your pain trend is rising week over week, jumping is pulled from the whole week. The elbow case is written out in full, because it is the one players ask about most.
Your level and your kit set the dose.
Only equipment you actually have is programmed — nothing is prescribed on the assumption you can improvise it. A beginner gets beginner movements, a fixed two-day week and no high-impact plyometrics. A club player gets at most two competitive-level movements a day — a cap the engine will relax only when your equipment and pain filters would otherwise leave the day empty. A competitive player is uncapped and gets an extra set on each day's primary lift. Every exercise is listed with the kit it needs, so you can see what your gym unlocks before downloading anything.
Session length is a real constraint, not a label: thirty minutes buys four main exercises, forty-five buys five, an hour buys six. The duration shown is computed from the sets, work and rest actually programmed. Players 45 and over get longer rest, an extra mobility slot and no high-intensity plyometrics.
Each week reads the last one.
When the week turns, the engine looks at what you logged. A week that felt easy and left no significant pain adds a set to each day's primary lift. A week that averaged hard — or a pain trend that is climbing — cuts every main set by about a third. The fourth week of a block is a scheduled deload.
Day to day, a two-tap check on how you feel adjusts that session: feeling beaten drops a set from every main exercise, swaps jumping for a strength alternative and adds thirty seconds of rest.
What it does not do.
Most apps leave this part out. It is the fastest way to know whether CourtFit is the right tool for you.
- It does not tell you how much to lift. You choose the load and log it. Progress totals it into weekly volume so you can see the trend, but nothing uses that number to pick your next load.
- It does not add reps or progress you to harder variations. Sets move; reps and exercise difficulty do not.
- It does not react the moment you finish a workout. The week changes when the week turns, or when you change your inputs — not the evening you log a hard session.
- It does not substitute for missing equipment. An exercise you cannot do is dropped, not replaced.
- The plan is not written by AI. No model chooses your exercises, sets or days — those are rules you could read. The app does include a separate AI chat, CourtFit Coach, which answers questions about the session you already have; it never changes the plan and never overrides the safety gate.
What you can do mid-session is swap an exercise for an alternative that trains the same quality and fits your equipment, with the options that avoid your flagged areas shown first. The swap list is a convenience, not a second safety gate — the screening that removes provocative movements happens when the plan is built.