What 'the math' actually does

You show up, log what you lifted, and the app handles the math for your next session. Here is what the app is actually doing while you rack the bar.

What Rackd reads

When you tap Finish, Rackd writes the session to your history. The numbers it cares about are simple. The weight on the bar for each working set, the reps you actually got, the RPE you tagged if you tagged one, and the program rule that owns this lift today.

That is the input. Last session, plus the rule.

The eleven progression systems

Every program in My Rack ships with a progression rule on each lift. There are 11 of these built in, and your program already chose the right one for the lift in question. A few you will recognise by name.

• Linear progression adds a fixed jump every session you hit reps. The Stronglifts engine.
• Double progression climbs reps inside a window, then bumps the weight when the top of the window is clean.
• Wave loading runs a 3-week cycle, climbing the percentages, then deloads.
• Percentage-based locks targets to a percent of your training max, the way 5/3/1 wants it.
• RPE-driven reads the RPE you logged and shifts the next session's target up, sideways, or down based on how hard the last one felt.

The other six cover bodyweight ladders, AMRAP top sets, ascending pyramids, descending pyramids, fixed-load accessories, and time-under-tension blocks. Your program picks the right one per lift. You do not have to.

What lands on your screen next session

When you open the next session, the targets are already filled in. Each working set has a weight chip and a rep range. Those are not guesses. They are the output of the rule applied to your last numbers.

If you nailed the last session, the targets climbed. If you missed reps, the targets held or backed off so you can clear them next time. If the program is a wave, the next session sits one step further along the wave whether you like it or not. The rules are honest like that.

When the math says deload

Some rules trigger a deload week on their own. Three missed sessions in a row on a linear lift, a failed top set on the third week of a wave, an RPE pattern that says you are cooked. Rackd cuts the load, writes a Coach Note that says deload week, and resets the climb when the deload is done.

That is the whole loop. Lift, log, repeat. The app does the bookkeeping so you do not have to.