Periodization in strength training: linear, undulating and block models

Types of periodization training in one table

Periodization training is a plan of changes to load, sets and reps across weeks, laid out in advance for a specific goal. You'll usually see three models: linear, undulating and block.

In studies, the last row without the lighter week serves as the non-periodized program: constant sets and reps (ACSM 2026). If you keep adding weight in it, muscle grows about as much as with the other models (results below).

Macrocycle, mesocycle and microcycle

Periodization is planned on three time scales, from a week to a year.

How to build one block and when to end it is covered on the mesocycle page.

Periodization for hypertrophy and for strength

Periodization gives a bit more strength than a program with constant sets and reps where only the weight goes up, but it doesn't build more muscle. For physique, training volume, meaning your weekly sets, matters more, and so does whether you keep adding weight or reps.

That's the result of a meta-analysis of 35 studies with equated amounts of work (Moesgaard et al. 2022), and the 2026 ACSM position stand concludes that with progressive overload, periodization is not clearly better than a constant program. The meta-analysis authors link the strength advantage to adaptations of the nervous system, not the muscle. That fits how a periodized block ends: with sets of 2-4 reps, which are the closest thing to a 1RM test.

The other planning topics are collected in the periodization and planning section.

How to periodize your training step by step

1. Write down your goal and date, e.g. “barbell squat, test in 12 weeks” or “more muscle, no date”.
2. Set the block length: 4-8 weeks. Past your first year of training, end it with a lighter week; in your first year, take a lighter week only when two sessions in a row go worse in most exercises. If the block ends with a test, the last weeks are a taper before the test (fewer sets and reps at a heavy weight), not a deload; take the lighter week after the test.
3. Pick the model for your goal from the table above and keep it until the block ends.
4. Make the first week a calibration week: choose weights that leave one more rep in reserve than the plan says (RIR 1 higher).
5. Write down the rule for the following weeks, e.g. “barbell squat: 4 × 10, +2.5 kg every week, fourth week lighter, then 4 × 6”.
6. After the block, compare your main lift in the same rep range: with a constant week, week 2 against the last regular week; in a linear or block model, week 1 of this block against week 1 of the next one, or your test result.

If the plan gives RIR instead of kilograms, on a weaker day the same RIR comes out at a lower weight and the plan still works.

With a constant week, you start the next block from the weights of your last regular week. In a linear or block model, you go back to the week 1 rep range with a weight based on your new 1RM, or 2.5-5 kg more than in week 1 of the last block, e.g. after a test in week 12 you start 4 × 10 at 67.5-70 kg instead of 65 kg. If you lift more in the same rep range at the same RIR, the block worked; compare your estimated 1RM only across sets with a similar number of reps.

In most gyms the smallest plates are 1.25 kg, so the bar goes up in 2.5 kg steps. On a 100 kg barbell squat that's 2.5%, but on a 40 kg barbell bench press it's over 6%, so in lighter lifts it's better to progress by adding reps. In the lighter week, leave the pin on a machine where it was and cut the number of sets, so you don't have to find your weights again after the deload.

Strength and physique coaches usually program a lighter week every 4-6 weeks (Bell et al. 2023). In our plans the deload comes only in week 8, because weeks 2-7 are identical, you end your sets at RIR 1-2 and fatigue builds slowly. After a block with a rising number of sets or with sets to failure, take the lighter week earlier.

Periodization examples: the barbell squat in three models

In these examples the Barbell Squat is done by someone with an estimated 1RM of 100 kg, so percent of 1RM and kilograms are the same numbers. You can work out the weights for your own 1RM in the 1RM calculator's plan weight mode.

Do the 1RM test in a rack with the safeties set just below the bottom position, after the warm-up from the 1RM calculator; without a test, the estimated 1RM from your last heavy set is enough.

Only the main lift changes with the model, while the Romanian Deadlift and the Seated Leg Curl stay in a fixed rep range with double progression for the whole block.

In the free 4-day upper/lower plan for intermediates, the Barbell Bench Press has three sets of 6-10 reps at RIR 3 in week 1, the same at RIR 2 in weeks 2-7, and two sets at RIR 4 in week 8. That's the constant week from the last row of the models table, and you progress with double progression.

Periodization vs linear progression and double progression

Periodization plans changes several weeks ahead, while progression tells you what to change in your next session.

Periodization sets the phases and their goals, while programming picks the exercises, sets and reps within each phase (Lorenz and Morrison 2015).

Common mistakes

1. A plan on paper only. The weeks are called “accumulation” and “transmutation”, but your log shows the same weights and reps for the whole block. If your log doesn't show which week was hard, the plan isn't working.
2. Periodization instead of sets. With the same amount of work, changing the model adds no muscle (result above). Before you rebuild a block, count the weekly sets for each muscle group.
3. A peak with no date. A taper, meaning 1-2 weeks with fewer sets and reps at 90% 1RM, only makes sense when a test or a meet is on the calendar. Without a date, alternate blocks with more sets and blocks of heavier sets, or train a constant week with progression.
4. A week off instead of a deload for no reason. In the only study on this, a week without training halfway through a 9-week program gave no extra muscle, and leg strength came out slightly worse (Coleman et al. 2024). If you don't need a break, deload instead: fewer sets, ended with about 4 reps in reserve.

What the research says about periodization

Meta-analyses compare periodization with a program of constant sets and reps, or the linear model with the undulating one; the certainty ratings in the claims table are our assessment. Read ES (effect size) like this: about 0.2 is a small effect, 0.5 moderate, 0.8 large.

In the Grgic et al. 2017 meta-analysis, studies lasted 12 weeks on average, and the other meta-analyses are also mostly made up of short programs. Whether any model wins over years is unknown. No study has compared periodization with a program adjusted as you go, without a preset scheme (Afonso et al. 2019), and ACSM notes that the order of changes in a plan is poorly studied.

What SmartWorkout logs show

Most longer plans built in the creator are therefore a constant week, the last row of the models table, and roughly one in three changes something between weeks. Every number is based on at least 50 people.

How to plan periodization in SmartWorkout

You build periodization in SmartWorkout in the plan creator: a plan is split into blocks, a block into weeks, and you edit each week separately.

1. On the Workout tab, next to “My Plans”, tap “See All”, then “+” and “Create new plan”.
2. Tap “Select load indicator” and choose RIR, RPE or 1RM (percent of your one-rep max) for the whole plan.
3. Tap “Add Block” and “Create mesocycle”, choose the number of workouts per week (1-6), and on the “Define Microcycle” screen the number of weeks (2, 4, 6, 8, 10 or 12) and the exercises for each workout.
4. On the “Define Mesocycle” screen each week has its own tab: change its sets, rep ranges or RIR according to your model and tap “Save”. The creator doesn't change them from week to week on its own.
5. If you plan a deload, leave fewer sets and raise the RIR in the last week of the block. There's no separate deload feature.
6. Add the next block with “Add Block” again. Press and hold a block's tab to clone it (“Clone”) or rename it (“Edit Block Name”), e.g. to “Accumulation”.

An AI plan repeats one week for several weeks; you add blocks and changes between weeks afterward in the plan creator.

With Premium, you see each muscle group's sets in every week of the plan against the volume zones, so you can tell right away whether the number of sets rises through the block.

You can paste the first week of a block through plan import (“Import plan” in the same “+” menu) and build the following weeks in the plan creator by cloning the week and changing the ranges. Import costs 10 AI credits, so the welcome credits cover it.

DAY: Lower A- Barbell Squat | WU 2x5 | 4x10 RIR 3 | TEMPO 20X0 | REST 180- Romanian Deadlift | 3x8-10 RIR 3 | TEMPO 3010 | REST 150- Leg Press | 3x10-12 RIR 2 | TEMPO 2010 | REST 120- Seated Leg Curl | 3x10-15 RIR 2 | TEMPO 2011 | REST 90

This is week 1 of the linear block from the example above. In week 2, set the barbell squat to RIR 2, in week 3 to RIR 1.5, in week 4 do 2 × 10 at RIR 3, and from week 5 switch to 4 × 6 at RIR 3.