MESO The rules Support

Volume you have to earn.

Meso reads what you actually lifted and writes next week from it. Beat last week and it adds a set. Stall and it holds. Every rule comes from published research, and the papers are in the app.

See how it decides Support
Coming to the App Store · iPhone · works offline, no account
A Meso workout screen: prescribed weight, rep window and reps in reserve, with last week's numbers beside every set.
A body map with each muscle coloured by how much work it has had this week against its evidence-based band.

Coverage

See exactly where the work is going

Every muscle is measured against the weekly volume the research supports, so an under-worked muscle is obvious at a glance rather than a surprise eight weeks later. Tap one and the app explains why it is the colour it is and what would change it.

The Science tab, listing each engine rule with links to the studies behind it.

Evidence

Every rule cited. Check our work.

Other apps say science-based. Meso shows the papers: each rule the engine follows is written in plain language with its citations, in the app, where you can read them mid-session if you want to.

How it decides

Five rules, and the research behind them

  1. Performance is the acceleratorBeat last week's best sets on a muscle and it earns one more weekly set. Stall and it holds. Regress and it drops.Mann 2010 · Helms 2018 · Enes 2024
  2. Soreness is only a brakeSoreness tracks damage and novelty, not growth, so it can hold volume back or cut it, but it never earns more.Damas 2016 · Damas 2018
  3. Reps first, then loadClimb the rep window, then add roughly 2.5 to 5 percent. Go heavier than asked and hold it across every set, and that becomes your working weight.Plotkin 2022
  4. Failure is rationedSets ramp from three reps in reserve down to one. Only isolation work touches failure, and only in the last hard week.Robinson 2024 · Refalo 2023 · Zourdos 2016
  5. Deloads come early when the data says soTwo weeks of regression across several muscles pulls the deload forward, because a sustained performance drop is the validated overreaching signal.Bell 2023 · Meeusen 2013

Anywhere

Gym, home, or a bar in a park

Gym

Barbells, machines and cables, with plate maths and warm-up ramps built in.

Home

Programs that need a floor, a wall and a sturdy table. Same engine, different lever.

Bar park

Calisthenics progressions that advance the movement when you top the rep window. Log vest weight and it switches to load progression.