Prilepin chart: strength training volume

The Prilepin chart helps answer a very practical question in strength training: how many reps should you do if your goal is to increase maximal strength? This is about neither getting a pump nor building endurance for prolonged muscular effort, but how sets, reps and percentages actually fit together.

Translator’s note: this topic is more complex than a typical training tip, but that is precisely why it deserves a detailed explanation. Prilepin’s chart may seem dry at first, but if you train the squat, press, deadlift or Olympic lifts, it provides a very useful framework for adjusting your training load.

Why does the Prilepin chart matter in strength training?

In the sixties and seventies of the last century, Russian sports scientist A. S. Prilepin collected information from more than a thousand training logs. These were no ordinary notebooks. The data came from Olympic weightlifters, including world champions, European champions, Olympic champions and national champions from various countries.

He used this information to compile what is known as Prilepin’s chart. The idea was simple: identify the loads at which strong weightlifters performed the most productive work without fatigue starting to undermine their progress. This is why the chart was later adopted in powerlifting and general strength training.

Here, intensity means the weight you lift as a percentage of your maximum. If your 1RM is 100 kg and you perform a set with 70 kg, the intensity is 70%. This matters a great deal because, in strength training, 70%, 80% and 90% are more than just numbers. They fatigue your body differently.

One thing immediately stands out in the chart: sets of more than 6 reps are rarely used to develop strength. The reason is simple. Longer sets generate a lot of fatigue, but the gains in maximal strength do not always justify it.

How do you read the Prilepin chart?

Take a load of 75% of your 1RM, for example. This falls within the 70–79% zone. According to that row, the following principles apply:

1. Sets in this zone consist of 3–6 reps.
2. Total volume falls within a range of 12–24 reps.
3. The optimal rep count is 18 reps.
4. If you perform fewer than 12 reps in total, the training stimulus may be too weak.
5. If you perform more than 24 reps, fatigue builds quickly and your movement may slow down.

This is the chart’s strength: it sets limits. But this is also where a problem arises. In an actual workout, you do not always use just one weight. What if you want to train at 65%, 70%, 75% and 80% on the same day? These fall into different zones.

If you took the optimal rep count for each zone separately and added them together, the volume would quickly become excessive. In this example, you would get 24 + 18 + 15 = 57 reps. You could end up with a workout that simply exhausts you instead of building strength.

PNLS, or Prilepin Number of Lifts Score

This problem is explained using the concept of the PRILEPIN NUMBER OF LIFTS SCORE, abbreviated as PTAK in Estonian. In English, it is called the Prilepin Number of Lifts Score, or PNLS. The idea is to assess how much of the allowable volume within one zone you use.

If you reach the upper rep limit for a given zone, your PNLS is 1. The formula is simple:

PRILEPIN NUMBER OF LIFTS SCORE = total number of lifts performed in a given zone / upper limit for total reps in that zone.

For example, if you bench press 2 x 6 at 60% of your 1RM, you have performed 12 lifts in that zone. If the upper limit for that zone is 30, then PNLS = 12/30 = 0.4. This means you have not used all the allowable volume.

If you add 5 x 3 at 75%, the PNLS for that portion is 15/24 = 0.625. Your total bench press score for 2 x 6 (60%) + 5 x 3 (75%) would be 1.025. For most zones, a score of around 0.7–0.8 works well in practice, although this depends on the exercise and your training level.

An important detail: PNLS is specific to each exercise. If your workout includes 5 exercises, you do not lump everything together. You should assess the volume for squats, presses, deadlifts and other exercises separately.

The Prilepin chart and INOL in practice

PNLS provides a good starting point, but one thing is missing. Let’s compare two workouts:

6 x 4 = 24 x 72%
6 x 4 = 24 x 77%

Both fall within the same zone, 70–80%, and PNLS = 1. Yet the second workout is harder. Training at 77% is more demanding than training at 72%, even when the total rep count is the same. This is where INOL comes in.

INOL links intensity with the number of lifts. The original idea was to compare intensities of 60%, 70%, 80% and 90% and the upper repetition limits for these zones. The formula is:

INOL = repetitions performed at a given intensity / (100 – the exact intensity of the weight lifted).

Let’s use the same example: bench press 2 x 6 x 60%, 5 x 3 x 75%.

INOL = 2 x 6 / (100 – 60) + 5 x 3 / (100 – 75) = 12/40 + 15/25 = 0.3 + 0.6 = 0.9.

Now consider two workouts with 24 repetitions each:

1. Workout 1: 6 x 4 = 24 x 72%. INOL = 24 / (100 – 72) = 0.86.
2. Workout 2: 6 x 4 = 24 x 77%. INOL = 24 / (100 – 77) = 1.04.

Now you can see the difference. The rep count is the same, but the higher percentage produces a higher INOL value. This is precisely why INOL is useful: it prevents you from oversimplifying and treating work at 72% and 77% as equivalent.

INOL favors more lifts at lower intensities and fewer lifts at higher intensities. This makes sense, because lifting at 90% and above causes much greater fatigue in the central nervous system. You cannot keep piling on heavy work indefinitely.

Here is another good example. What is the difference between doing 5 x 2 x 80% and 2 x 5 x 80%? In both cases, the total volume is 10 repetitions and INOL = 10/20 = 0.5. But they may not feel the same.

With 5 x 2 x 80%, the work is broken into smaller chunks: INOL = 5 x 2/20 = 0.1 + 0.1 + 0.1 + 0.1 + 0.1. With 2 x 5 x 80%, each set is harder: INOL = 2 x 5/20 = 0.25 + 0.25. The first option is usually easier to tolerate because the fatigue is spread across smaller chunks of work.

Prilepin chart: practical limits

When you plan strength training across different intensity zones, calculate INOL separately for each major exercise. This helps you see whether the training load is distributed sensibly or concentrated into a single day. Spreading the week’s work across several workouts often leaves you fresher than squeezing all the volume into one session.

Based on the author’s observations, frequent workouts with an INOL value of 0.6–1 per session work well for many people. Of course, not everyone can train that often. In that case, you need to be especially thoughtful about how you distribute the volume.

Weekly INOL ranges for an exercise such as the deadlift, squat or press:

• < 2 — light, easy to tolerate and suitable after weeks of very heavy training loads.
• 2–3 — hard but tolerable, with a good training load.
• 3–4 — brutal, exhausting and highly fatiguing; suitable for a short, clearly defined period or to shock the system.
• > 4 — frankly, at this point you should question whether the plan still makes sense.

INOL ranges for an exercise or lift within a single workout:

• < 0.4 — too few repetitions, leaving the training stimulus weak.
• 0.4–1 — a good range; you feel fresh, and the training load is tolerable and conducive to progress.
• 1–2 — tough, but usable during periods of high training load.
• > 2 — a very heavy training load that you should not repeat lightly.

The simple truth is that the chart does not write your training program for you. It helps you check whether the volume and intensity of your strength work are in balance. If you do 4 workouts a week and use only 70% in every session, your INOL may add up on paper, but that does not automatically mean you are developing maximal strength in the best possible way.

There is also the question of how much of your weekly INOL should come from high intensities, such as 90% and above, and how much can come from lighter weights. This depends on your training cycle, recovery and goal. A common approach is to perform a lift 2–4 times a week, depending on whether you are maintaining your current level, increasing your training load or preparing for heavier attempts.

The Westside system is often described as using 2 days per week for each lift: a heavy day and a speed day. In this case, INOL is split between those days. Is it better to keep speed and heavy days separate, or to combine different intensity zones in both workouts? There is no single answer, but the Prilepin chart at least provides a framework for keeping volume in check so it does not become arbitrary.

FAQ: Prilepin chart

Is the Prilepin chart only suitable for Olympic weightlifting?

Its use does not have to be limited to Olympic weightlifting. The original data came from Olympic weightlifters, but the principles are also used in powerlifting. The squat, bench press and deadlift are good examples of exercises to which the chart’s logic can be applied.

Does INOL need to be 1 for every workout?

No. An INOL of 1 may be a reasonable limit, but if you train frequently, 0.6–1 per workout may be more manageable. A higher number does not automatically mean a better workout.

Why doesn’t the chart emphasize sets of more than 6 reps?

When training for maximal strength, fatigue builds quickly with longer sets. If your goal is to improve your 1 RM, you need enough heavy work, but not an endless accumulation of reps.

Reference

Original text: How to design strength training programs using Prilepin`s table, Hristo Hristov. http://ambesc.com/lifting/prelipins.pdf

Translator’s note: the original text was difficult, particularly because of the formulas and quantities involved. The most practical elements, however, are the INOL coefficient and the levels at the end of the article. These give you a tool for assessing whether your training load is too low, about right, or already too exhausting.

Translated by: Janar Rückenberg

Come and train! ArtGym