Double progression and how hard the effort felt

The principle

Double progression is the simplest and most proven method for making progress in strength training. You work within a rep range (for example 8 to 12). As long as you don't reach the top of the range, you keep the same load and add reps. When all your sets get there, the load goes up by one increment — and you start again from the bottom of the range. Azetta adds your perceived effort to this: a set that succeeded but only just should not make the load go up.

The Azetta method

The question after the exercise

After an exercise, the app asks how many more reps you could have done (reps in reserve): 0 (failure), 1 (very hard), 2 (ideal), 3 (comfortable) or 4 or more (easy). The answer is converted into perceived effort out of 10 (RPE):

You can also say whether the load was too light, just right or too heavy. On its own, this answer is worth an RPE of 7, 8 or 9.5. Combined with reps in reserve, "too heavy" gives at least 9 (9.5 if you were at 9; 10 stays 10); "too light" gives at most 8, and takes 0.5 off an RPE of 8 or less, without going below 6.

By default, the question is asked once per exercise and applies to its last normal set; you can have it asked after every set, or turn it off.

The rule from one session to the next

Only the heaviest sets of the session are read (not the warm-up or drop sets). Let max RPE be the highest of these sets:

Without an answer to the question, reaching the top of the range is enough to go up. For a bodyweight exercise, going up means shifting the range by one rep (8-12 becomes 9-13), and the app never goes down.

This is the basic rule, when you train regularly close to what was planned. The article on adaptive load describes what comes on top of it: a gap of 3 reps or more from the plan recalibrates the load (at most +10% or −15% from one session to the next), a break of more than 14 days lowers it, so does the exercise's position in the session, and with a pyramid or with alternating ranges, the load follows your estimated 1RM rather than this table.

During the session (question after every set)

• RPE ≥ 9.5 → the next set loses 1 increment.
• RPE ≤ 6, or RPE ≤ 7 with the top of the range reached → +1 increment.
• RPE ≤ 7 below the top of the range → +1 rep, up to 2 above the range.
• "Too heavy" forces at least −1 increment, "too light" at least +1, "just right" keeps the same load and the same reps for the next set.

How the session felt

At the end of the session, you can say whether it was easy, good, hard or exhausting. For sets logged without RPE, this counts as 7, nothing, 9 or 9.5: "hard" keeps the load, "exhausting" lowers it.

Why this choice

• Double progression guarantees progressive overload without complicated calculations: you gain reps, then load.
• The RPE scale based on reps in reserve has been validated for strength training; it lets the load be adjusted to how you feel on the day.
• Aiming for about 2 reps in reserve leaves enough stimulus while limiting fatigue and the risk of failure.

Limits

• Everything relies on your honesty and your practice at estimating reps in reserve: beginners tend to underestimate themselves.
• Progression happens in fixed increments: an exercise where one increment is a lot (2 kg on dumbbells for lateral raises) progresses in jumps.
• The rule looks at the last session of the exercise: one bad day can lower the load once.

References

1. Helms ER, Cronin J, Storey A, Zourdos MC. Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training. Strength and Conditioning Journal, 2016;38(4):42-49.
2. Zourdos MC, Klemp A, Dolan C, et al. Novel Resistance Training-Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve. Journal of Strength and Conditioning Research, 2016;30(1):267-275.
3. American College of Sports Medicine. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Medicine & Science in Sports & Exercise, 2009;41(3):687-708.