How to gain muscle.. Optimally & Scientifically

I have been on a push, pull, legs split for about a year. Although I have seen great progress with this split, I have run into one major issue with its workload. The problem? Consistency.. Leading to over training/ junk reps. Oh you don’t believe in overtraining? Well science would disagree with you. Don’t believe in junk reps? Weirdly enough science would also disagree with you there too.

Are you now asking yourself what Junk reps are? I know you are. Well you’re in luck because I’m going to tell you all about it. So Junk reps occur when you work past the optimal amount of training a singular body part in one session. If you don’t know what optimal means, you probably didn’t complete college like my good friend and training partner Dev. It’s okay you can google it.

Think about doing 10 sets of any specific exercise in a workout. You do each set till failure. How many sets do you think actually contribute to muscle gain? If you think all 10 contribute to muscle gain then I think you should really try to understand what I’m putting down about junk reps. As you do each set, you will continue to get diminishing returns on the set. Until eventually I would argue that the added fatigue and recovery time will outweigh the potential muscle gain. However, which set should we stop at? I can confidently tell you right now we don’t want to do 10 sets of any singular exercise as this will just create an excessive amount of fatigue without the added reward.

These ideas and issues made me want to put this paper together. I wanted to put this paper together so I can train better, but I also realized all my gym rat friends might want to hear my overall thoughts on this as well. Training at an “optimal” level is something that has always interested me. It interested me because growing up in sports I would always do whatever coaches and teachers told me to do for a workout. I didn’t know any better. Turns out they really didn’t know what they were doing and a lot of the training I did in high school was just outright wrong. It wasn’t until I got to college that I finally was coached by someone who knew what he was doing in terms of training. I still can’t believe I was doing Crossfit for football, volume training for sprinting, and running miles for no good reason other than some decent cardio. The funny thing is a lot of you that will read this will probably just be doing some workout because someone told you to do it. Or you saw some fitness influencer who’s clearly blasting tren doing something that is backed up with no evidence. If you’ve taken any advice from Troy Adashun… Please read this paper.

Let’s put together a few parameters that we’ll want to focus on to reach near optimal workouts every time. We will have limits on a daily and weekly volume to avoid overtraining and junk volume. This in turn will allow us to reach an optimal frequency for training. The intensity in which you are training plays a huge role and we should make sure that we are hitting this correctly. Finally, we’ll have to look at ideal rep ranges based on the focus of your training. When building this we’ll rely on scholarly articles, studies, and a small amount of anecdotal evidence. I want to rely as heavily on science as we can here. Let’s start with building the correct daily and weekly volume with a study.

Daily and Weekly Volume:

According to the study above, Table 1 suggests that the best amount of sets per muscle per session is 6. Admittingly, this curve above will not pertain to everyone. Not everyone will see a slight decline in muscle growth after 6 sets. An argument I could make here for going over 6 sets is that you are guaranteed to be close to optimal no matter what. There’s an issue with that thought and this is the main motivation for me wanting to change from push, pull, legs. On my push days I would do anywhere from 12-15 sets of chest exercises. These 12-15 sets would give me muscle growth. However, I would then be sore for the next 2-3 days and I would sometimes even be a little sore going into my next push day. This would without a doubt affect my next push day and I wouldn’t be able to get that same chest stimulation I had in my first push day. I actually ended up getting injured a couple times and I believe that these “junk reps” could be to blame. Ever since I’ve switched over to limiting my sets I haven’t gotten injured since.

Also it’s fair to mention, what was the point of doing those extra 6 - 9 sets if I would have gotten the same muscle growth with fewer sets. Those sets were technically junk reps. I know however mentally I will not be satisfied on a push day if I only do 6 sets of chest! This is why I want to encourage a hybrid split (I’ll get into this later). I hope that my split can satisfy those people who want to stay at the gym a little longer. Realistically, all you need is an hour a day in the gym and you could reach the volume necessary to be considered “optimal''. Mike Mentzer, a famous bodybuilder, would even argue less than an hour.

As a result from this study in table 1 I will hit a max of either 6 to 12 sets dependent on the muscle group. There are a few intricacies with this and certain muscles can be pushed farther than others. With all this said I think the optimal number of sets should be around 6. Just because I am saying you can do 12 sets on a muscle and be okay doesn’t mean I think it’s optimal. For some people the optimal will be different than others. Finding out what works best for you will take time but I think basing it off of 6-8 sets a day should give you the best results most of the time.

I also found another study based on this topic very interesting and I felt like I should mention it here. Although this study will not affect the parameters we want to hit for optimal muscle growth I think it should be noted just in case you plan to take on powerlifting. The graphs below show the amount of training volume effects in a workout to strength gains measured by 1 rep max.

It’s crazy to me that people on average who did 1 set of bench in their workouts had more strength gains than someone who was doing 5 sets. With this said, if you’re training to get stronger then you should really consider minimizing your sets. I’m not saying do 1 set for your workouts but I would say that a possibility for plateauing on your lifts could be due to the fact you're doing too many sets for a muscle group. Now this same study took a look at these set ranges on hypertrophy and this was found:

This table suggests volume does have a significant effect on muscle growth. Of course this study doesn’t even get up to the magical 6 sets we found in the original study but this study does agree with what was found in the first study shown.

Weekly volume in this plan will be limited by the amount of sets that can be done given the split and maximum amount of sets per session. The reason why I won’t incorporate a weekly volume restriction is because there is very little scientific based evidence on weekly training volume. We should instead be focusing on the amount of training achieved in each session and the amount of recovery time given for those muscles trained. I personally believe a weekly volume will differ so much person to person based on goals, recovery, and type of training.

Before I leave this topic there is one sentence that spoke to me in the study. This is for anyone doing a bro split: “This indicates that the "bro-style" of training each muscle group once per week, blasting each muscle with up to 20 sets per body part or more, may be an inferior way to train.” We’ll get into appropriate splits later.

Intensity

How close till failure should you be taking your lifts? There are a handful of research papers on this question. However, the answers from these research papers aren’t clear. In fact, a lot of these papers disagree with the others. Some found that you should be lifting till failure, while others found that lifting till failure actually performed worse than not lifting till failure. What are we supposed to believe works best if there are differentiating opinions?

Even with no clear resolution there is a few things we can take away from these articles: As long as we are training past a 5 in RIR (reps in reserve) then we will achieve hypertrophy. This means as long as we train past having only 5 reps left in the tank then hypertrophy will be achieved. Therefore if we are completing a working set we must at least perform enough reps that only 4 or less are left in the tank.

Everyone will have different responses to intensity and there is no correct answer to how intense your sets should be. Not everyone understands their own RIR. Make sure you understand how many reps you can actually perform with a weight before you try to hit a certain RIR. Having correct RIR is important if you want to achieve hypertrophy.

There are a lot of opinions on the amount of intensity and there is one I would like to share that I personally believe works the best. Mike Isreatel, PHd stated on Jeff Nippards revived stronger podcast that effective reps to growth have what is called an S curve when reaching that 5 RIR. As you get closer to that 0 RIR you will get smaller and smaller amounts of muscle growth but each rep will be significantly more important than any rep before the 5 RIR. Like the graph below but imagine a flatter line until the 5th RIR.

Training intensity should always be a focus in the workout. In summary, any working set should be a 5 RIR or lower. Training till failure should happen but it doesn't need to happen consistently to build muscle. You should know your RIR for best results.

Personally, I would suggest shooting for the 0-2 RIR range in all working sets. A lot of these studies were based on individuals with low training experience which I believe could have pushed the effective RIR number a little higher than it should be. I would try to aim for a system with my First set hitting an RIR of 2 - 3, then a second set hitting an RIR of 1-2, and my third and final set going till failure.

Rep Range

This is another commonly asked question. What is the ideal rep range for hypertrophy and what is the ideal rep range for strength? These rep ranges might be a lot more similar than one might think. This idea, like many others in the fitness industry, is also very controversial and there is no “right” answer here. Paul Carter, a strength and hypertrophy coach believes that only the last 5 reps till failure matters. He uses a model called the effective reps model by Chris Beardsley.

This effective rep model agrees with our prior statement that our working set must achieve an RIR of 5 or lower. Paul Carter argues that well if the only reps that matter are the last 5 then what is the point of all the reps before the last 5. I think this is a very valid argument to make as it is shown that the last 5 reps is what builds muscle. Carter also explains that the reps preceding the last five are simply just adding fatigue. Therefore a rep range of 5-8 is optimal as it will limit the added fatigue from the reps that don’t matter. This idea that rep ranges don’t matter in hypertrophy actually agrees with the studies done by Schoenfeld et al in 2014 and 2015. Schoenfeld did a study from 3 to 35 rep range and found the hypertrophy results were the same. However the strength result differed from the low rep ranges to the higher rep ranges with lower rep ranges having a larger impact on strength gains.

If you are aiming to become stronger than I would say any rep range from 1-5 makes a lot of sense. This is how powerlifters workout and the proof is in the results. I don’t think there is too much to be said on this but if you disagree please fax over your complaints to your local powerlifter.

The Split

There is no way of running push, pull, legs without running into a rest amount issue. The problem is there are three specific types of days in the workout and one lift I love that is considered a back and leg workout. You’ve probably guessed it. It's a deadlift. So whether you’re deadlifting on your pull days or your leg days is not the issue. The problem is that when you deadlift you will not allow the appropriate amount of rest needed to get back to a leg day or pull day. For example, if you were to do a push day on day 1, pull day on day 2 with deadlift, and then finish with day 3 being a leg day I would most definitely argue that your posterior chain of your legs have not been given an optimal time of recovery. Well then you might say you can just focus on a leg workout that only does quads and calves in which I would say good luck with that because there are very few movements that you can do that isolate your quads. Now if you do deadlift on your leg days, I would argue it’s a little bit better but I would still prefer at least 48 hours of rest until between a pull day and a deadlift day for optimal conditions for training.

Now I’m not saying push, pull, legs is bad and might even be optimal for you. If you’re on gear then optimal is a lot different for you then people like me who aren’t. But let’s be honest, if you were on gear why the hell would you be reading this philosophy from this guy who has absolutely no credentials? Like let’s be honest, if you’re on gear the only thing you’re reading is the number of MGs going into that syringe.

So what split do I think is optimal? It’s actually a hybrid split of upper and lower and push pull legs. The split is really only for a 5 day span with an additional rest day to make it 6 days. The split goes as follows:

Day 1: Upper

Day 2: Lower (Squat)

Day 3: Pull

Day 4: Push

Day 5: Lower (Deadlift)

Day 6: Rest and Recovery

Repeat.

This split will allow at least 48 hours of recovery for any muscle group and provide more frequency than push,pull, legs. The only thing that is worse about this split than push pull legs is the amount of time you’ll be spending in the gym on your upper days. Yes, you will be spending a lot longer time in the gym on your upper days than any of you other days because you will literally be hitting all of your muscle groups above your lower back. This day will require a lot more awareness of fatigue than most days. Make sure that you are able to hit the amount of reps you should be hitting in your last sets. If you can’t, go home and call it a day.

If you want to avoid that long and exhausted upper day and you can train six times a week I would try this split:

Day 1: Chest and Back

Day 2: Lower (Squat)

Day 3: Pull

Day 4: Push

Day 5: Lower (Deadlift)

Day 6: Arms

Day 7: Rest and Recovery

Repeat.

I’m actually planning to transition to this above split because I want to focus on arm growth and a given day will allow for more focus on them.

The Summary

Now that we have covered volume, intensity, rep ranges, and the ideal split you are now ready to get out there and train optimally. Well at least this is what I believe to be optimal based on the studies I’ve found. Ultimately, you’re going to want to find what works best for you but I should mention that this structure should help you have near optimal workouts. In order to encorporate these thoughts into you workouts make sure you avoid junk volume, train to an RIR of 5 or less, hit ideal rep ranges for your focus, and follow a hybrid split.

Now this doesn’t cover a lot of things that matter for training in general. Sleep, Diet, types of exercise, and genetics are all big determinants on how you’ll grow. I chose not to focus on these topics because I was more interested in building a structure that I can use for my future workouts. Also I wanted to mention a few influencers that gave me inspiration and information to do this. I think these people are great follows on instagram and or youtube. The following are Paul Carter, Chris Bumstead and Jeff Nippard. Thanks for reading.

Sources:

“Set Volume for Muscle Size: The Ultimate Evidence Based Bible.” Weightology, weightology.net/the-members-area/evidence-based-guides/set-volume-for-muscle-size-the-ultimate-evidence-based-bible. Accessed 8 Aug. 2023.

Set volume for Muscle Size: The ultimate evidence based bible. Weightology. (n.d.). https://weightology.net/the-members-area/evidence-based-guides/set-volume-for-muscle-size-the-ultimate-evidence-based-bible/#Schoenfeld