Periodization basics: planning training in blocks

Periodization means planning how your training changes over the weeks. If you're new to lifting, you don't need a formal plan like that yet. Steady progression matters more: a little more weight, or one more rep, over time.^[1] For muscle growth, studies found about the same results with or without periodization.^[2][3]

For strength, periodization may give a small edge, but the studies disagree.^[1][2][4] Two common styles, linear and undulating, are explained below. For people new to lifting, they gave about the same gains.^[5][2]

Why isn't this obvious? Because periodization sounds like what serious lifters do. Heavy blocks, light days, a peak timed for one big day. It's easy to feel behind without a plan like that. The research is less impressed than the internet is.

The last article covered when to take an easier week. That's one planned week. This one zooms out to the plan across many weeks.

Why it matters

The cost of getting this wrong is mostly time and attention. It's rarely muscle.

The common trap goes like this. A beginner reads about heavy phases and light phases, then writes a complicated 16-week plan before they can squat with steady form. A plan you keep rewriting is hard to judge. If your numbers stall, you can't tell whether the plan was wrong or you missed half the sessions.

The opposite mistake is smaller but real. You read that "periodization doesn't work", then drop a good program because it changes the reps from week to week. But with the same total work, periodized and non-periodized plans built about the same muscle in the studies.^[2] What a beginner needs first is to add a little over time (see progressive overload).

What the research says

A few terms first. A meta-analysis pools the results of many studies on the same question into one estimate. A systematic review gathers all the studies on a question in a planned way. An umbrella review is a review of reviews. A position stand is an official summary of the evidence by a group of experts. Here, that's the American College of Sports Medicine (ACSM). Hypertrophy means muscle growth. Your one-rep max (1RM) is the most weight you can lift once.

When studies are volume-matched, both groups did the same total work (the same sets and reps over the program). Only the way it was arranged differed.

The styles, in plain words

• Non-periodized: the same sets and reps the whole way through. You still add weight as you get stronger.
• Linear (also called traditional): the weight goes up and the reps come down, phase by phase, usually every few weeks. For example, 3 sets of 12 for four weeks, then 3 sets of 8 with more weight, then 3 sets of 5 with more still.
• Undulating (also called non-linear): the weight and reps change more often. In daily undulating plans they change within the week: sets of 5 on Monday, sets of 12 on Wednesday, sets of 8 on Friday. In weekly undulating plans they change from week to week.
• Block: the program is split into blocks of several weeks, and each block has its own main goal.

Even experts don't agree on one definition of periodization.^[1] The ACSM panel also notes that papers often treat "periodization" and "programming" as the same thing.^[1] Expert consensus. This is the panel's view, not a tested finding.

For muscle growth: about the same either way

Strong evidence. Studies found about the same results either way. That's narrower than "periodization does nothing". It means that with the same total work, the way it was arranged didn't change how much muscle people built.

Linear against undulating gave the same picture. A 2017 meta-analysis of 13 studies compared linear with daily undulating plans and found no difference in muscle growth.^[6] The 2022 analysis found the same.^[2] The ACSM's 2026 stand, which drew on these reviews, says the same.^[1] Strong evidence, with the caveat below about who was studied.

For strength: the studies disagree

Mixed evidence. Here's what each side found.

• A small edge. In the 2022 volume-matched analysis, periodized training gave slightly bigger 1RM gains than non-periodized training.^[2] The effect was small, and the low end of its range sat close to zero. Moderate evidence for a small effect.
• A bigger edge, less certain. A 2017 meta-analysis of 18 studies found a moderate strength advantage for periodized plans.^[4] The 2024 umbrella review judged its results too varied from study to study to be sure.^[7]
• Can't tell. The ACSM's 2026 stand said the effect of periodization on strength could not be determined.^[1]

There's a reason for caution about the older studies. A 2019 review looked at the 21 studies behind two earlier meta-analyses. None compared a periodized plan with a non-periodized plan that also varied its training. Eight compared other things altogether, such as one set against several sets.^[8] Expert consensus. This is the authors' view, not a tested finding. It explains why the strength results are hard to read.

In the 2017 analysis, people new to training gained more from periodized plans than trained people did.^[4] So "periodization only matters for advanced lifters" isn't a fair summary either. The fair summary: you don't need periodization to make progress now. Any extra strength it adds is disputed. The study that kept total work the same found it small.^[1][2] Mixed evidence.

Linear or undulating for strength

A 2015 meta-analysis pooled 17 studies with 510 people. In 16 of them, both styles increased strength. It found no difference between linear and undulating plans for upper-body or lower-body strength.^[5] A 2026 meta-analysis of 29 studies with 704 people found the same.^[9] The average ages in its studies ranged from 14 to 80. It included people with obesity and some athletes.^[9]

The 2022 analysis found a small strength edge for undulating plans overall. But the edge showed up only in people who already trained. In people new to training, linear and undulating plans gave about the same strength gains.^[2]

Moderate evidence that the two styles give beginners about the same strength gains. Limited evidence for the edge in trained lifters. It's one subgroup result, sitting right on the line of chance. The 2026 analysis didn't find that edge in trained people.^[9]

What nobody has tested

You'll often read that periodization times your progress or prevents overtraining. The 2019 review found that none of the 21 studies tested those timing claims.^[8] The 2024 umbrella review said the reasons behind any strength edge remain unclear. None of the reviews it looked at checked whether periodized groups just trained heavier right before the final test.^[7] Nobody has studied this well yet.

What about block periodization? The 2022 analysis couldn't pool comparisons of other styles, because there were too few studies.^[2] We couldn't find a good comparison of block plans in everyday gym-goers.

How to apply it

Steps 1 and 2 follow from the studies above. Steps 3 to 5 are coaching practice, not a tested finding.

1. Run one program that adds weight or reps over time. That's the part that drives progress now. You don't need to add a periodization layer on top.
2. If your program changes reps across days or weeks, follow it as written. Linear and undulating plans gave beginners about the same results. Don't swap one for the other chasing an edge.
3. Write every set down. A plan is only as good as your record of whether the numbers went up.
4. Think about planned phases later, when steady progress stalls for weeks. That's also when it may be time to look at when to change your program.
5. If you try it, keep it simple. A few weeks at 8–12 reps, then a few weeks heavier at 5–8 reps, is a plain linear plan.

A worked example

Maya weighs 70 kg and has lifted for two months. This week she squats 40 kg × 8, 8, 8. Next week she aims for 40 kg × 9, 8, 8. When she reaches 10, 10, 10, she adds 2.5 kg and starts again at 8s.

That's non-periodized in the strict sense. The rep range stays the same and the weight creeps up. It's enough for now.

A linear version of her next 12 weeks might look like this:

• Weeks 1–4: 3 sets of 12.
• Weeks 5–8: 3 sets of 8, with more weight.
• Weeks 9–12: 3 sets of 5, with more weight again.

For muscle growth, the studies found about the same results either way. For strength, they disagree on whether the linear version adds a small edge.

This is where practical and best-on-paper can differ. On paper, a periodized plan might add a little strength. In practice, a plan only works if you run it. Maya keeps the simple one until it stops moving.

Common mistakes

Building a complex plan in month one. Periodization sounds like the serious way to train. But with steady progression, periodized plans weren't clearly better.^[1] Fix: run one simple program and add a little each week.

Hunting for the best style. Daily undulating and block plans get talked up as superior. For beginners, linear and undulating plans gave about the same results.^[5][2] Fix: pick the program you'll follow, whatever style it uses.

Expecting periodization to time your progress. Plans that promise a peak in week 12 sound precise. But none of the 21 studies in the 2019 review tested those timing claims.^[8] Fix: judge a plan by your logged numbers, not by its promises.

Treating "no clear benefit" as "useless". "No clear extra muscle" is easy to hear as "pointless". But the same studies found periodized plans did no worse either.^[2][3] Fix: if your program already changes the reps over time, keep following it.

How Gymbers fits

Programs in the Gymbers app are written by coaches who train. They run in blocks of weeks, with every session laid out in order. Some programs raise the target effort from block to block, for example from about 4 reps in reserve (RIR) to 2–1. RIR is how many more reps you could have done before you had to stop. That's the coach's planning choice, not a research-tested formula. Start it and the app shows you the next session.