What players can rely on
Ultimate Gym Game officially describes three zones: Strength, Hypertrophy and Endurance. Ultimate Gym Game strength and Ultimate Gym Game stamina searches map here because the public Trello adds a rep-system view: Strength 1-3 reps, Hypertrophy 4-8 reps, Endurance 9-16 reps, and Junk 17+ reps.
The Trello gives clear direction but still needs ownership caveats and current in-game verification. Use these ranges as checked planning guidance, not as a promise that every machine has an identical hidden multiplier.