Back squat progression: warm-up ramp, top set and rep-max ladder

A 120 kg back squat for five at RPE 8 is worth about 148 kg for one. The same set says the warm-up before it should be the bar, 60 kg, 85 kg and 102.5 kg, and that 120 kg is roughly the lifter's 7-rep max. Every number here comes from the model the app runs on each logged set, worked out with compute.mjs, so you can check them against the one-rep max calculator.

This guide covers what the back squat trains, how to log it so the numbers mean something, the ramp and the ladder for a 120 kg working set, which of the seven progression schemes suits a 5 to 8 rep squat, and what to swap in when you cannot squat.

What the back squat trains

In the app's exercise library the barbell back squat is a compound squat-pattern lift with quads and glutes as the primary muscles, and hamstrings, core and spinal erectors as secondary. Working sets count toward the weekly set targets for quads and glutes. Adductor work has no slot of its own on the 14-muscle grid and is counted under quads.

Depth changes what grows. In a 10-week study with two sessions a week, full squats and half squats added a similar amount to the knee extensors (4.9 and 4.6 per cent), but the full squat group gained more adductor volume (6.2 against 2.7 per cent) and more gluteus maximus volume (6.7 against 2.2 per cent) [1]. Hamstring volume did not change in either group [1]. A squat is a quad and glute lift. If you want hamstrings, program a hinge or a leg curl alongside it.

How to log a back squat

A back squat is a load lift, not a bodyweight-plus-load lift, so you log the weight on the bar and nothing else. It is not a per-side lift. One set is one line in the log.

Give each set a role. The sets before the working weight are warm-ups or ramp-ups and never count toward volume. The heaviest set of the day is the top set. Anything after it at a lower load is a back-off. The app only counts normal, top and back-off sets as working volume, so the warm-up ramp below adds nothing to your weekly quads total however many sets it has.

Log RPE on the top set at least. The scale is reps in reserve: RPE 10 means no reps left, RPE 9 means one, RPE 8 means two [2]. A set logged without RPE is treated as RPE 10, the assumption every classic one-rep max formula makes. For the squat that assumption is close to how strong lifters actually rate a true max. Fifteen powerlifters working up to a 1RM rated the squat 9.6 out of 10 on average, and RPE tracked percentage of 1RM with a correlation of 0.88 to 0.91 across the three lifts [3]. The numbers are good enough to plan from, provided they are honest.

The warm-up ramp for a 120 kg working set

The app builds the ramp from the planned weight of the first working set. For 120 kg, compute.mjs warmup --kg 120 returns four sets.

The working set itself is two 25 kg plates a side. Each ramp load is rounded to the nearest 2.5 kg, and any candidate heavier than 95 per cent of the working weight is dropped, because a set that close to the working load is a working set with a different label. A fifth set, a single at 90 per cent, only appears once the working weight passes 120 kg, so a 125 kg day gets one more set than this one. The plate counts are from the plate calculator, which the app opens from any barbell set.

Reps fall as the load rises: eight, five, three, two. The ramp exists to groove the pattern and wake the legs up, not to spend reps you want in the top set.

What 120 kg for five at RPE 8 is worth

Five at RPE 8 means two reps in reserve, so 120 kg was a 7-rep load that day. The model reads the published reps-by-RPE chart along its diagonal, where the key is reps plus reps in reserve, and comes out at 81.1 per cent of 1RM. That makes the estimated one-rep max 148 kg. Epley gives 140 kg and Brzycki 135 kg for the same set, because both assume the fifth rep was the last one possible.

From that 148 kg the model produces a rep-max ladder: the heaviest load for each rep count at RPE 10. The compute.mjs ladder --kg 120 --reps 5 --rpe 8 output is below.

Read the ladder as a planning table. The five-rep rung is 127.7 kg at RPE 10, so 120 kg for five at RPE 8 and about 127.5 kg for five at RPE 10 describe the same lifter. A back-off set of eight at RPE 8 sits two rungs below the 8-rep max, around the 10-rep load of 109.4 kg.

The curve is strictly decreasing, so a 15-rep max can never beat a 12-rep max, and the model stops at 30 reps. Past 12 reps it leaves the published chart and follows an Epley-shaped tail, which is why the calculator calls estimates above 10 reps rough. The sibling guide on how the estimated 1RM is built goes through the chart and the tail in detail.

Which progression scheme suits a 5 to 8 rep squat?

The app has seven schemes: Auto, Double, Top set + back-off, Load, Reps, RIR and Manual. For a squat worked in the 5 to 8 range, two fit well.

Top set + back-off matches the way most lifters already squat. You set a rep band for the top set and a target RPE, and the back-off sets sit at a fixed percentage of the top set. When the top set lands in the band at or under the target RPE, the next session's top set goes up by one plate-loadable step and the back-offs follow. A grinder, meaning a top set well over the target RPE or well under the rep floor, holds the load instead of adding to it. At 120 kg the step is 2.5 kg, the smallest change a pair of 1.25 kg plates allows.

Double progression suits straight sets, three or four sets of 5 to 8 at one load. You add reps until every set reaches the top of the band, then the load goes up and the reps reset to the floor. The scheme reads the whole session, not the best set, so one set of eight and two sets of six keeps you at the same weight for another week.

A few rules hold across every scheme. A planned deload week never emits an increase. More than 30 days off a lift resets it rather than pretending the old number still stands. And on a cut, a load increase never leaks through; the plan holds while the deficit does its work. Three sessions without progress flags a stall by default, which for a squat is the point to check depth, sleep and the RPE you have been logging before you blame the program.

Put the squat first in a lower session. The library's default rest for it is three minutes, and the top set is the one you want fresh legs for.

Mistakes lifters make with squat progression

The most common one is logging without RPE. The same 120 kg for five logged with no RPE is treated as a max and comes out at 139 kg instead of 148 kg. Nine kilos of strength vanish from the chart, and the next weight the scheme suggests is pinned to a set that was never a max.

Letting warm-ups count is the second. Tag the ramp as warm-up or ramp-up and the weekly set target for quads stays honest. Leave them as normal sets and a four-set ramp doubles the apparent volume of a three-set squat day.

Depth creep is the third. As the load rises the squat gets shallower, and the adductor and glute growth that depends on a full squat goes with it [1]. A 148 kg estimate from half squats and a 148 kg estimate from full squats are different lifts, and the trend line cannot tell them apart.

Treating the ladder's top rung as a target for a test day is the fourth. The estimate is built to track a trend over weeks. It is not a promise about the next single.

Substitutions and what changes when you swap

A front squat or a safety-bar squat keeps the pattern and the quads but moves load off the shoulders and onto the upper back. A hack squat or leg press removes the balance demand and lets you push the quads close to failure with less fatigue to the back. A Bulgarian split squat is a per-side lift, so the app logs left then right and counts both sides toward working volume.

Whatever you swap in, the estimated 1RM and the ladder belong to the exercise they came from. A 148 kg back squat estimate says nothing about a front squat, and the swap starts its own history. Keep the swap for a block, log RPE from the first session, and the new lift has a ladder of its own within a few weeks.

Questions

How many warm-up sets before a heavy back squat?

For a 120 kg working set the app's ramp is four sets: the empty bar for eight, 60 kg for five, 85 kg for three and 102.5 kg for two. A fifth single at 90 per cent only appears above 120 kg, and nothing within 5 per cent of the working weight is ever a warm-up.

Does a squat logged without RPE count as a max?

Yes. A set with no RPE is treated as RPE 10, the same assumption Epley and Brzycki make. For 120 kg for five that gives 139 kg instead of the 148 kg an honest RPE 8 produces. If you stopped two reps short, log RPE 8 and the estimate matches what you had left.

Why does the ladder show my working weight as a 7-rep max?

Because five reps at RPE 8 means two reps in reserve, and five plus two is seven. The model keys the reps-by-RPE chart on reps plus reps in reserve, so 120 kg for five at RPE 8 and 120 kg for seven at RPE 10 land on the same rung at 81.1 per cent of 1RM.