If you compared a full body vs split routine, which would be better for gaining muscle size and strength? This has been a controversy for years. A new study was published recently in the prestigious Journal of Strength And Conditioning Research (Ramos-Campo 2024) which aimed to finally settle this debate. I’ll get to the study details in a minute, but first some important background stuff…
Obviously, resistance training is the key to gaining muscle size and strength. You don’t gain maximum muscle by doing a bunch of cardio or calisthenics and stuffing your face with a bunch of food. But it’s not enough to simply lift weights, you must follow the best practice guidelines for all the acute training variables.
One of the most important of those variables is training frequency. Some people think of frequency as how many workouts you do each week. That’s one definition. An even more impactful one is how many times you work each muscle per week.
For quite a few years, the idea was pushed hard that you had to work each muscle twice a week to max out your muscle gains. If you did a so-called “bro split” and hit each muscle only once a week, people would laugh sneer, and say you’re doing it wrong.
However, when exercise scientists studied this more closely (Schoenfeld 2016), they found that your training frequency doesn’t matter that much if the weekly volume (how many sets you do) is equal.
For example, if you work each muscle twice a week (higher frequency) and do 6 sets for chest each workout, that’s 12 sets per week. And if you work each muscle only once a week but you do 12 sets in that single workout, that’s still 12 sets per week. The weekly volume is equal. When this is the case, current science suggests that muscle growth will be similar.
To be fair, a slightly higher volume might have some advantage. Some studies suggest higher frequency training is better for strength gains (I believe that’s true). There’s also a theory that more frequent training stimulates muscle protein synthesis more times per week, producing more muscle gain over time. (I’m not sure about that – protein synthesis is a proxy for anticipated muscle growth, not actual growth).
Either way the fact is, lots of people work each muscle only once per week and get great results, from young pro bodybuilders to older recreational lifters. In light of recent evidence, low frequency training programs have made a comeback, and I can confirm that based on the popularity of routines like my 4 X 4 Muscle and physique program. It’s one of our best sellers for advanced lifters with physique / hypertrophy goals.
To this day, there’ s still a widespread belief that higher frequency training is better. However, what we’ve discovered is that when people increase their training frequency, it allows them to increase their weekly training volume, and it’s not the higher frequency per se that leads to more muscle gains, it’s the higher weekly volume.
So, after all this research, we now have a pretty good understanding that you can gain muscle on any of those splits I mentioned (2-day, 3-day, 4-day and yes even a 5-day “bro split”) if the weekly volume is the same.
But one question has remained:
Full body vs split workouts: which is better for muscle and strength gains?
Most bodybuilders and physique enthusiasts seem to think that split routines are far superior to full body workouts for building muscle. You might have observed this yourself, and there is also some evidence supporting this idea.
A study of male bodybuilders (Hackett 2013) found that out of 127 competitive bodybuilders surveyed, more than two-thirds trained each muscle only once a week! The other third used 2-day or 3-day splits. None of the athletes used full body workouts. Zero! Stop and think about that.
This would suggest that either bodybuilders know what they’re doing instinctively and split routines really are better, or they’re following a bodybuilding tradition that isn’t supported by science.
Why do so many bodybuilders gravitate to split routines and appear to shun full body training? Well, they probably notice they get better results on split routines. They also might simply enjoy that type of training more (the pump and the way the workout feels).
There are also scientific reasons why split routines might be more effective for hypertrophy. On split routines, you can do more volume (more sets) in a single session for a single muscle. This can increase the metabolic stress which is one of the proposed mechanisms of muscle growth. There’s also more time (days) between workouts for each muscle, which means you get greater recovery.
If you work each muscle only once every 5 to 7 days, that’s a lot more time between workouts than if you train every muscle every other day. Although a single body part really gets blasted in one session, many people who use my 4 X 4 Muscle and Physique program (the “bro split”) say they love this enhanced recovery aspect of the workout.
Despite all these facts, there’s still been a ton of controversy over which split routine and training frequency is best. Even less known is how full body workouts compare to all these split routines.
Previous studies have shown that strength and muscle size gains were similar with both full body and split routine training.
But in one well-done study (Bartolomei 2021), the researchers found a difference between strength gains and muscle gains. The group that did full body training had better strength gains while the split routine group had better muscle size gains. Anecdotally, this matches what we see in the real world: strength athletes often lean toward full body training, while physique athletes lean toward split routines.
With all these questions unanswered and controversies unsettled, a group of researchers from Spain decided to go back and analyze every study that has been done comparing full body vs split routines and try to resolve the debate once and for all.
While there have been quite a few studies that examined full body workouts vs split routines, believe it or not, there had never been a systematic review and meta-analysis until now.
The first full body vs split routine systematic review and meta-analysis
What the scientists did was search all the research data bases looking for studies that compared split vs full body routines. To be included, the studies had to meet these criteria: subjects were 18 to 40 years old (average 25 years), they compared split vs full body workouts, and they measured strength or muscle mass gains (lean body mass or cross-sectional muscle area). Drug users were excluded.
After sifting through 3108 scientific articles, 14 studies were chosen to be included in the meta analysis. Out of the 14 studies, 2 included women, 1 included both men and women, and the rest were all men.
Here were the results: strength gains, as measured in the upper body (by one rep max in the bench press) and in the lower body, were similar in both the split routine and full body routine. Muscle size gains were also similar when comparing split routines and full body routines.
The researchers summed up the results by saying:
“The main findings suggest that the choice between split and full body routines has minimal effect on strength gains and muscle growth when considering equal training volumes, in programs ranging 4 to 12 weeks.”
These results came as a surprise to many people in the bodybuilding community, as most physique athletes favor split routines. But if you think about it, the results shouldn’t be that surprising when you consider the huge body of research comparing different split routines (like the 2-day, 3-day, 4-day and 5-day programs).
In all of these different split routines, even when comparing 2-day splits where each muscle is worked twice a week and 4 or 5-day splits where each muscle is only worked once a week (or thereabouts – maybe once every 5 or 6 days), we see the same thing: If the weekly volume is matched, the muscle growth is similar.
This being the case, it almost seems like an obvious conclusion that if the weekly volume is the same on a full body routine as compared to a split routine, that the results would also be similar.
This gives us even more evidence to strengthen the argument that weekly resistance training volume is more important than your choice of training schedule (split or full body). There are some caveats however.
Even when weekly volume is the same, when you use split routines where you’re only hitting one or two major muscles per workout, you need to do a lot of sets (volume) in a single session. There is some evidence that excessive volume in a single session can cause so much fatigue and muscle damage that it might not be optimal. Individual results may vary, but this is one reason some people choose higher frequency schedules – so they can spread the volume across the week instead of doing a ton of sets in one workout.
In the end, here was the conclusion: Because the study found that split or full body routines both give similar results in strength and muscle size, the researchers said:
“Individuals are free to confidently select a resistance training routine based on their personal preference.”
Study limitations, opinion, and editorial
Rather than believing there is one universal best program, choosing training programs based on personal preference is important. Personally, I prefer split routines. Specifically, my favorites are 3-day and 4-day splits where I work each muscle once every 4 to 6 days. Of the two I like 4-day splits the most.
Programs that work each muscle only once every 7 days can be effective, but my opinion is that this is indeed a low frequency, and I see slightly better results with a slightly higher frequency, but not necessarily working each muscle 2 or 3 times per week.
I don’t enjoy full body training. I find that my focus feels scattered having to work every muscle in the body in one session, whereas I get a far greater mind to muscle connection when training fewer body parts in a session, especially when there are only 1 or 2 major muscles to work.
One thing I’ve noticed is that on the occasions when I did do full body training, my strength gains were higher than on bodybuilding-style body part split routines. Much higher. But the downside was I did not see as much muscle size gain. That runs contrary to what this new meta-analysis suggests, but it does match some of the previous research like the Bartolomei study.
As all good researchers do, the authors revealed some limitations to the study, and I could also point out some myself.
One is that the subjects were aged 18 to 40. This means that we can’t necessarily generalize these findings to older adults. In addition, only 3 of the 14 studies included women. There has been previous research (Hagstrom 2020) suggesting the same conclusions probably hold true in women. However, more research is needed to confirm this.
The studies analyzed also included trained and untrained subjects and this is a huge factor to consider. It’s very possible that highly experienced bodybuilders might indeed get better muscle gains on split routines.
My experience combined with results like we saw in the Hackett study (where 100% of competitive bodybuilders used split routines and 0% used a full body routine), while anecdotal, is not evidence I’m going to ignore. It’s important to consider your experience level and current condition as well as personal preference when choosing a training schedule.
I believe however, that in the general population of recreational lifters, the results of this new meta-analysis will hold true. If you like full body routines, use full body routines. If you like split routines, use split routines. If you like split routines, choose whichever one you prefer. Don’t get caught up with paralysis by analysis – they all work. And don’t be a program hopper – choose a program and stick to it long enough to milk it for all it’s worth before switching to a new one.
One last note: You don’t have to think in either or terms. It may be a smart idea to change up your training schedule over the course of each year. This way you can experiment and see what works best for you and what you enjoy the most.
Like most people, I do have favorite training schedules that I use most of the time, but there could be major benefits to varying your training schedules rather than sticking to the same one for life – if not more muscle gains, then certainly less boredom. That’s a subject that would be great to see researched more in the future.
Tom Venuto,Founder of, Burn the Fat Inner CircleAuthor of Burn the Fat, Feed the MuscleAuthor of The BFFM Guide to Flexible Meal Planning For Fat Loss
PS. This is the 4 X 4 “Bro Split” Where you only work each muscle once a week. Very popular for people who want more recovery and only want to workout out 4 days a week: 4 X 4 Muscle And Physique
About Tom VenutoTom Venuto is a natural bodybuilding and fat loss expert. He is also a recipe creator specializing in fat-burning, muscle-building cooking. Tom is a former competitive bodybuilder and today works as a full-time fitness coach, writer, blogger, and author. In his spare time, he is an avid outdoor enthusiast and backpacker. His book, Burn The Fat, Feed The Muscle is an international bestseller, first as an ebook and now as a hardcover and audiobook. The Body Fat Solution, Tom’s book about emotional eating and long-term weight maintenance, was an Oprah Magazine and Men’s Fitness Magazine pick. Tom is also the founder of Burn The Fat Inner Circle – a fitness support community with over 52,000 members worldwide since 2006. Click here for membership details
Scientific References:
Bartolomei S, et al, A comparison between total body and split routine resistance training programs in trained men, Journal of Strength and Conditioning Research, 35: 1520-1526, 2021.
Dankel S, et al, Frequency: The overlooked resistance training variable for inducing muscle hypertrophy?, Sports Medicine, 47: 799-805, 2017.
Evangelista A et al, Split or full body workout routine: Which is best to increase muscle strength and hypertrophy? Einstein, 19: 1-9, 2021.
Gomes G, et al, High-frequency resistance training is not more effective than low-frequency resistance training in increasing muscle mass and strength in well-trained men, Journal of Strength and Conditioning Research, Sports Medicine, 48: 1207-1220, 2018.
Hackett D et al, Training practices and ergogenic aids used by male bodybuilders, Journal of Strength and Conditioning Research, 27: 1075-1093, 2013.
Hagstrom A et al, The effect of resistance training in women on dynamic strength and muscular hypertrophy: A systematic review and meta-analysis, Sports Medicine, 50: 1075-1093, 2020.
Ramos-Campo D et al, Efficacy of split versus full-body resistance training on strength and muscle growth: a systematic review and meta analysis, Journal of Strength and Conditioning Research, epub ahead of print, 2024.
Schoenfeld B et al, how many times per week should a muscle be trained to maximize muscle hypertrophy?, Journal of Sports Science, 37: 1286-1295, 2016.
