The Science Of Muscle Building and Strength In 4 Sets Or Less

The Science Of Muscle Building and Strength In 4 Sets Or Less

What’s this about 4 sets or less rubbish? Everyone knows you have to put in serious work for serious results. True, true. But there is a science to muscle building and it can be done in 4 sets or less.

What if you could put in just enough work to receive fantastic results while still having plenty of time to do other fun stuff.

As usual, we’ll mix in a little anecdote, glaring SpelLiNg errors, and ridiculous pictures to craft our wild narratives.


Are more sets better than a single set for exercises?

If you aren’t sure why we’re starting with this question, you may not have visited enough fitness forums and witnessed the troll pack in full attack-mode.

Needless to say, people get really worked up about this question.

On one end, you have the traditionalists who claim multiple sets per exercise provides sufficient stimulus for the muscle to grow. Simple, easy; I like it.

On the other end you have a group of non-conformist who say a single set per exercise performed with enough intensity can yield maximal results as well. Simple, easy; I also dig it.

But who’s right?

Maybe both.

There is a lot of grey area in the research regarding this, but it appears that when we look across the greater body of evidence, we find that there is greater support for doing multiple sets per exercise than a single set.

And when I say greater support, there are more studies that support multiple sets.

Meaning, if today you are barbell squatting, it’s probably better to do 3 sets of squats than 1 set of squats. If this seems obvious, know that there is some serious debate on the subject.

Multiple Sets on Strength

In 2002, a study on recreationally trained men showed that training with 3 sets was superior than training with 1 set. But this was only 1 study, and it only included 16 guys.

Different researchers found the same thing in 2005.

James Krieger, a prolific researcher, performed a terrific meta-analysis (analyzing multiple studies)  on single vs multiple sets in 2009. This meta-analysis included 14 studies and found 2 to 3 sets per exercise are associated with 46% greater strength gains than 1 set. 

And again, researchers in 2017 found the same thing the previous three studies found. Multiple sets are better than one set for strength.

And to be honest, this is only the tip of the iceberg. There are piles more studies that show multiple sets leads to strength gains. Studies on everything from powerlifting to physical therapy modalities.

Multiple Sets on Muscle

We all like strength, but what we really like is MUSCLE.

Tell us about the muscles…

Krieger was back at it again in 2010 with an eight study meta-analysis on muscle gain (this man is a savage). He found that multiple sets are associated with a 40% greater hypertrophy-related effect size than 1 set.

In other words, multiple sets were found to be a pretty big deal in gaining muscle when compared to one set.

In all fairness, there have been researchers on the other side of the fence (review 1, review 2) and they aren’t thrilled about Krieger’s multiple sets finding. This turned into a full blown nerd statistics fight.

Both sides presented strong arguments.

After the dust was settled, Krieger defended himself again and staunchly stood by multiple sets with quality data.

As you can see, both sides have support grounded in research. There just so happens to be MORE support for multiple sets.

You are the judge and jury, so it’s truly up to you. Decide what “excites” you more.

History Can Shine Light On The Science Of Muscle Building

The funny thing about research is that you can support anything if you are willing to look hard enough.

Honest to God this is true.

I found a study that showed getting stung by a bee on the penis shaft creates maximum pain (brave researcher). The author/researcher allowed bees to sting him in 24 other places—including his scrotum.

I don’t know about you, but if I see a bee land on said appendage….it’s lights out time.

Masochism aside, if you’re persuaded 1 single set is the way to go, you can find plenty of research to support that training style. You should be aware that the necessary intensity for this style of lifting is another debate all together.

On the other hand, if you like doing more work in the gym (multiple sets), you’ll find ample research to support multiple sets.  

And in the case of multiple sets, the research theme is fairly clear—multiple sets are a really good idea for the average guy.

More importantly, multiple sets aren’t shown to be ineffective. This is a fairly important point and here’s why: the 1-set proponents are arguing that you don’t need more than 1-set, but they aren’t arguing multiple sets are ineffective. Conversely, research supporters of the multi-set method are arguing that the 1-set method isn’t enough to maximize strength and muscle.

If researchers can prove that one set is effective, than we automatically validate that three sets are also effective because you have to do one set to get to three (3rd grade math—woot woot).

My recommendation: follow history.

There have been a few bodybuilders that followed the low set approach (Mentzer/Yates/Jones), but most world champion bodybuilders, powerlifters, and physique athletes have trained with multiple sets.

Arnold, multiple sets. Zane, multiple sets. Haney, multiple sets. Coleman, Jackson, Wheeler, Gironda—multiple sets. “Supplements” probably assisted these guys, but that’s a different subject.

And what about the great strength and physique coaches of our day: Simmons, Poliquin, Thibaudeau, King, Wilson, Abel—and so many others—multiple sets.

Walk around your gym and look at the guys with great physiques—more often than not—multiple sets.

Male gymnasts don’t earn those bicepticons by doing 1 pull up per day.



Normal Joe Fit Recommendation

My recommendation along with the majority of strength and physique coaches would be multiple sets per body part per day.

  • Low energy day: 2 sets per exercise
  • Moderate energy day: 3 sets per exercise
  • Feeling like a savage?: 4 sets per exercise


Einstein tells us 3 sets per body part may be better than one set

How many exercises per muscle group per day?

Above we saw that on a given day, exercising with multiple sets per exercise is a good idea. But what if I do two or three exercises per body part on that day? Isn’t that like 6-12 sets per day? Is that too much? Let’s make the science of muscle building simple.

As we recommended in our sets article, 10-15 sets per week per body part per week is a sweet middle ground for muscle and strength. The question at hand is how do we divvy up those sets throughout the week?

In NMJ fashion, there isn’t a “best way”, but there is a “smart way”.

If at all possible, train each muscle group at least twice per week. Exposing a muscle to multiple bouts of weekly stimulus is a great way to build muscle and strength. Learn more about this topic in our high frequency training article.

A safe recommendation for number of exercises:

First decide how many sets you are going to do. NMJ suggestion is to choose 10-15 sets per week per muscle. Let’s arbitrarily say you are going to do 12 sets for back over the course of a week. Using the frequency method, you’ll train back at least twice this week.

There are two popular methods (and many more) that you can utilize.

The Equal Method: 

The equal method is simple. Take your sets (12) and divide them equally across your workouts. In our case, it will be 12 sets divided by 2 workouts: 6 sets per day.

Day 1:

  • Back exercise 1: 3 sets
  • Back exercise 2: 3 sets

Day 2:

  • Back exercise 1: 3 sets
  • Back exercise 2: 3 sets


Note: You’ll notice that we chose 2 back exercises instead of doing all 6 sets on 1 exercise. The reason? It’s more fun and it allows you to train the back at multiple angles. We could get more scientific, but let’s not. Variety is great.

The Energy Method:

In this method, you’ll put more work in the front OR back of your week depending on your schedule, stress, sleep quality, and the difficulty of workouts over the course of a week.

For example, you might have decided to do a lot of leg work in the beginning of week. To keep total body fatigue manageable, you may choose to do most of the back work in the back half of the week when leg volume lightens up.

Day 1 (beginning of week):

  • Back exercise 1: 2 sets
  • Back exercise 2: 2 sets

Day 2 (end of week):

  • Back exercise 1: 4 sets
  • Back exercise 2: 4 sets


There are many days I walk into the gym with zombie-body and realize quickly that it’s a “get a few sets done and get out” kind of day. A few days later, I’ll make up some of the work if I’m feeling re-energized.


Ben Franklin tells us to stop worrying about every fitness detail

The Recap:

  1. Doing multiple sets (2+) per exercise is a great way to increase muscle and strength.
  2. Doing a single set (1) per exercise can work, but it is not as strongly supported in research literature.
  3. 10-15 sets per muscle is great weekly volume.
  4. 2-4 sets per exercise per muscle is a safe bet for muscle and strength enhancement.

Lift some, play more, love life.