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The BEST Workout Split to Build Muscle (in 2025)

by Jeremy Ethier - November 24, 2024

What is the best workout split for muscle growth? The worst? Find out here.

In this article, I’ll be ranking 7 of the most popular workout splits to find the top performers all the way down to the ones that are wasting your time.

And at the end, I’ll add a bonus factor, time efficiency, to see which workout split gets you the most gains in the least time.

Now, to ensure your workout split doesn’t end up at the bottom, it has to perform well on what I call the hypertrophy score. A measure of how well it builds muscle.

To calculate the score, I teamed up with PhD researcher Eric Trexler.

Partnership with Dr Eric Trexler to determine best workout split

Together, we used the latest research to build a predictive growth equation focused on 2 key factors to judge every workout split:

  1. Frequency: How often each muscle gets trained per week
  2. Volume: The number of sets each muscle is worked with

The best workout split will strike the perfect balance of both.

Analyzing Every Workout Split

3-Day Push-Pull-Legs 

Let’s start with a classic, the push-pull-legs workout split, where you train all your:

  • Pushing muscles on the first day
  • Pulling muscles the next day
  • Legs on the third day
3 day push pull legs workout split

But the unique thing about this workout split is you can run it once, so you’re only training 3 days a week, or you can run through it twice for 6 training days per week.

I’ll score the 3-day-per-week version first, with a hypertrophy score of 6.7.

And while it takes the top spot on the leaderboard for now, the next workout split will give it a run for its money. 

3-Day Full-Body Workout Split

It’s the 3-day full-body workout split.

Unlike the 3-day push-pull-legs workout split, which hits each muscle just once per week, the full-body split trains every muscle 3 times per week. 

3 day full body workout split

This gives it a major advantage.

A recent meta-analysis by Josh Pelland and colleagues found that training a muscle 3 times per week can boost strength gains by about 50% compared to training it once per week — even with the same weekly volume.

So, if your bench went from 100 lbs to 150 lbs on the push-pull-legs split, switching to full-body could push it to 175 lbs in the same time.

That’s why I personally recommend this workout split for beginners who should focus on mastering and progressing their main exercises before worrying about adding more volume. 

How much does this help muscle growth, though?

Well, while the latest data suggests frequency doesn’t seem to be as important for growth, it still helps provide a small boost. 

In this case, it’s enough of a boost for the 3-day full-body workout split to take the top spot with a hypertrophy score of 8.1.  

4-Day Upper/Lower Workout Split

Next up, we’re moving to a 4-day routine with the classic upper/lower workout split, which focuses on the upper body for 2 days and the lower body for 2 days.

4 day upper lower workout split

Now, unlike the full-body workout split, which trains each muscle 3 times per week, here, each muscle is hit just twice per week. However, this split does allow for an extra workout day, meaning you can fit in more volume — and that may be a bigger driver of growth.

For example, look at the graphs from a recent study comparing the effect of frequency and volume on muscle growth.

The frequency graph is quite flat, meaning you get just a small boost in growth as you train each muscle more frequently. Meanwhile, the volume graph moves up and to the right, suggesting that higher volumes continue to push more growth. 

Because of this, the upper/lower split scores quite well, with a hypertrophy score of 8.4, just enough to earn the top spot.

5-Day Upper/Lower/Push/Pull/Legs (U/L/P/P/L)

But now it’s time to step things up with the 5-day splits.

Starting with my personal favorite and the routine I’m currently following, the Upper/Lower/Push/Pull/Legs workout split. 

5 day upper lower push pull legs workout split

The beauty of this hybrid routine is that it allows you to fit in more volume than the 4-day upper-lower split, but it doesn’t come with the big-time commitment of something like a 6-day push-pull legs split.

This makes it the perfect option if you’re looking to take your training to the next level without going overboard.

And with a hypertrophy score of 9.0, it takes the top spot on our leaderboard. 

But will this be enough to beat the rest of the splits?

Or will I find something even better than what I’ve been doing?

5-Day Bro Split

Let’s find out by moving on to the classic 5-Day bro split.

Unlike any of the splits we’ve covered, the bro split involves dedicating a whole workout to each muscle group.

5 day bro split workout split

This makes it a favorite among bodybuilders like Arnold, who loved working each muscle to exhaustion with tons of volume.

However, since you’re only training each muscle group once per week, it’s probably not the best way to distribute your weekly volume.

In fact, a criticism of the bro-split is the idea of “junk volume”.

Because you’re doing so much volume per workout for just 1 muscle, by the time you reach your 3rd or 4th exercise in your workout, your performance drops considerably.

Some believe those exercises now become a waste of time and would be better off moved to another workout day when your muscle has recovered.

But we definitely need more research to see just how much of a difference this would make. 

For now, let’s see how it scores.

Is it enough to beat my personal favorite workout split?

Not quite. It slides into a close second place with a score of 8.8. 

5-Day Full-Body Workout Split

Alright, next up, we have the 5-day full-body workout routine, an ultra-high frequency split that trains each muscle 5 times per week.

5 day full body workout split

Now, although this sounds like a bad idea, in each workout, you’re only doing a few sets per muscle.

Allowing you to push hard during those sets yet still recover well even if you’re training that same muscle the very next day. 

But what’s interesting is this training style may provide additional benefits for growth, especially as you get more advanced.

Every time you lift weights, you’re “signaling” your muscle to grow — something known as the muscle protein synthesis response.

But here’s the thing.

Research has shown that this response lasts quite long, about 48 to 72 hours, for beginners. This means you only really need to train each muscle 2, max 3 times per week, to keep the protein synthesis response elevated throughout the whole week.

In advanced lifters, however, this changes.

The protein synthesis response shortens and can last just 12-24 hours.

Because of this, advanced lifters may benefit from higher-frequency splits to keep stimulating muscle growth and avoid any “downtimes” where muscles aren’t being signaled to grow.

But this is all just theoretical.

The real question is, does this really lead to more growth?

Well, one study published back in 2019 put this split to the test.

Instead of using beginners, they took well-trained lifters, split them into 2 groups, and had them follow nearly identical workout routines with the same exercises and the same amount of sets and reps.

The only difference?

One group did the exercises using a 5-day full-body workout split, whereas the other used a 5-day bro split.

The result?

After 8 weeks, almost every muscle measured grew more with the full-body workout split than with the bro split.

As for its hypertrophy score, after crunching the numbers, it scored an all-time high of 10.0, taking the top spot by a long shot. 

6-Day Push-Pull-Legs

But it’s not over yet.

There’s still 1 more workout split left to cover that might take the win, and it’s every gym bro’s favorite routine. The 6-day push-pull legs split. 

5 day push pull legs workout split

Now, although this routine trains each muscle only twice per week, less than half as often as the previous 5-day full body split, you can fit in a ton of volume because of how many days you’re in the gym.

But is this enough to give it the number 1 spot?

Well, after crunching the numbers, it comes in ...

… at a close second with a score of 9.7.

Ranking Every Workout Split Based On Muscle Growth

Workout split overall ranking

So, here’s how I’d rank all the splits purely based on muscle growth:

  • Best: 5-day full-body
  • Great: 6-day PPL
  • Good: 5-day ULPPL, 5-day bro split, 4-day UL, 3-day full-body
  • Worst: 3-day PPL

What About Time Efficiency?

But unless you’re someone who would live, eat, and sleep in the gym if it meant more gains, you should also consider time efficiency.

And I don’t just mean how many days a week you work out.

There are other factors you need to consider, like warm-up sets.

Full-body workouts are usually longer because you have to take time to warm up both your upper and lower body.

It’s one of the reasons why, despite the 5-day full body routine having the highest hypertrophy score, I still choose not to use it.

So, the real question becomes: which workout split offers the best gains for the least time commitment?

To answer that, we calculated the weekly time investment you’d spend on each workout split and compared it to its hypertrophy score.

We found a split that gives you 85% of the gains of the top split but with 30% less time in the gym every week. 

And that split is ... the 4-day upper/lower split.

TL;DR

  • To determine the best workout split, I worked with PhD researcher Eric Trexler to build a predictive growth equation focused on 2 key factors: frequency and volume.
  • For 3-day splits: the full-body version (8.1) scores better than the PPL (6.7) because it may boost strength gains by about 50% — even with the same weekly volume.
  • The 4-day UL workout split allows more volume, which may be a bigger growth driver than frequency. This gives it a score of 8.4.
  • For 5-day splits: the ULPPL comes in with a score of 9.0 (more volume without big time commitment), bro split 8.8 (slight disadvantage: theoretical “junk” volume), and full-body 10.0 (could help continuously stimulate muscle protein synthesis in trained lifters).
  • Finally, the 6-day PPL came in with a score of 9.7.
  • Bonus: the 4-day UL workout split gives you 85% of the gains of the 5-day full-body split — but with 30% less time in the gym weekly.

To help you guys out, I’ve created a free downloadable PDF for both the 5-day full-body and the 4-day upper/lower routines.

I will be making updated articles for some of these routines, but for now, you can download them completely free and follow them step-by-step at the gym here:

I will be making updated articles for some of these routines, but for now, you can download them completely free and follow them step-by-step at the gym here:

Click the button below to download the workout routines:

Also, I’m getting ready to launch a brand new project I’ve been working on for years.

I can’t wait to share it with you guys.

We’re putting the final touches on it, but trust me when I say it’ll be the most powerful, science-backed tool you can use to help with your fitness journey. So don’t forget to keep an eye out so you don’t miss it.  

But for now, if you want a more personalized approach that tailors your workouts based on you and your body, just take our quiz below to discover the best program for your body:

Click the button below to take my analysis quiz to discover the best program for you:

Otherwise, check out these articles for some:

Thanks for sticking to the end, and I’ll see ya next time! 

By the way, here’s the article summed up into a YouTube video:

Best vs Worst Workout Splits to Build Muscle (in 2025)

The BEST Workout Split to Build Muscle (in 2025)

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