Optimal protocols for building strength and growing muscle, with Dr Andy Galpin
Andrew Huberman interviews exercise scientist Dr Andy Galpin on the science of strength training and hypertrophy.
Summary
Andrew Huberman hosts Dr Andy Galpin, an exercise scientist, for a focused discussion on the science and practice of strength training and hypertrophy. Galpin opens by arguing that resistance training is the single most important tool for combating neuromuscular aging — a benefit that cannot be obtained through any other form of exercise — and that the loss of muscle power with age (8–10% per year) is far more dangerous than the more commonly cited loss of muscle size (1% per year). He then walks through the essential non-negotiables of any effective training program — consistency, progressive overload, individualization, and appropriate target selection — before laying out specific, actionable protocols for both strength and hypertrophy training. A key distinction he draws is that strength training demands precise execution, high intent, and compound movements performed when neurologically fresh, while hypertrophy training is comparatively flexible and "idiot-proof" in programming terms, requiring only that total weekly volume per muscle group is sufficient and that sets are taken close to failure.
Key Takeaways
FULL TRANSCRIPT
Why strength and hypertrophy training matters beyond aesthetics
Andrew Huberman: Today we're talking about strength and hypertrophy. Right out of the gate, I want to ask you: why should people think about and train for strength and hypertrophy — not just people who want bigger biceps, but people who have longevity goals and health goals unrelated to what most people associate with hypertrophy? What are the benefits of training for strength and hypertrophy for the everyday person, for the athlete, for the recreational exerciser?
Dr Andy Galpin: One of the major disservices we've done in this field is convince people that things like strength training are for athletes or for growing bigger muscles, and that cardiovascular training is for things like fat loss and heart health. That is a tremendous disservice because it puts up a lot of unnecessary barriers, leads to a lot of false assumptions, and therefore poor actions.
We could do a hundred episodes on the benefits of exercise, running all the way from mood and focus and cognitive tasks to better immune function — you'll get fewer colds and fight them off more effectively — to mortality. Some of the strongest predictors of how long and how well you will live are exercise-related. However, there are independent benefits that come from endurance training and independent benefits that come from strength training.
To give you one categorical answer: resistance exercise and strength training is the number one tool to combat neuromuscular aging. You cannot get that through any other form of exercise besides heavy overload strength training. If you want to be alive and live by yourself, you have to be able to engage in human movement. If you have any dysfunction in the neuromuscular system, you're not going to be able to do that. And the only way to preserve that or fight that loss with aging is to strength train.
People tend to hear numbers like you lose about 1% of muscle size per year after around age 40, and that's true. However, what they don't realize is you lose about 2 to 4% of your strength per year. So the loss of strength is almost double the loss of muscle mass with aging. Muscle power is more like 8 to 10% per year. We can very clearly see that the problem you're going to have with aging is not going to be preservation of muscle — although that is incredibly important — it's going to be very specifically preservation of muscle power and strength. Why that really matters is your ability to stand up and move, your ability to catch yourself from a fall, your ability to feel confident doing a movement. That is a function of muscle power more than it is muscle size. Functionality is really what we want. You want to be able to do whatever you want physically and feel confident doing it as you age. That's only going to be obtained through strength training.
Andrew Huberman: Is it appropriate to say that training for strength and hypertrophy is also a way to keep your nervous system healthy and young?
Dr Andy Galpin: Yeah, absolutely. It is the only exercise route we have for that. The wonderful thing about strength training is you don't actually have to start at a young age. I was reading a paper this morning because of our previous conversation — it was in people over age 90. These are folks 90 and older, and they saw improvements of 30 to 170% in things like muscle size and hypertrophy over a very short period of time, I think 12 weeks. The reason I like to mention that is because if you're listening and you're 50 and you haven't been strength training, you're not toast. You should absolutely start now. You're going to be able to get to a fantastic spot very quickly.
Defining strength versus hypertrophy
Andrew Huberman: If you would please remind us what strength and hypertrophy are in terms of the specific adaptation they represent. When somebody is training for strength, what are they really training for? Obviously it means the ability to move more weight, but I know it includes a number of other things as well. And when one is training for hypertrophy — for the growth of muscle fibers — what does that represent? I think if people understand that, they will far better understand the methods and protocols that are going to be best for each.
Dr Andy Galpin: At its core, you've basically described it. When we talk about strength, we're talking about an actual function — can you create more force across a muscle, muscle groups, or a total movement? When we talk about hypertrophy, we're specifically referring to just an increase in size. There's no actual mention of function. A muscle can grow larger without actually technically being stronger. However, there is a strong relationship between strength and hypertrophy, so a lot of the time in lay conversations we lump those two things together.
We have to recognize that for people who are new to training or even intermediately trained, there is a huge overlap between strength and hypertrophy. Once you get past that, they become disentangled. There's a lot of confusion because people think either these are the same thing, or that if I want to get stronger I have to get bigger — which is not the case at all. If you want to get stronger and you don't want to add muscle for any reason, whether personal preference or aesthetics, it is quite easy to get stronger without adding much muscle mass. So differentiating these two things: one is simply a measure of size and the other is a measure of force.
Essential components of any effective training program
Andrew Huberman: What are the essential components of an effective strength and hypertrophy protocol?
Dr Andy Galpin: What I'd like to do is walk you through both, because as we mentioned they overlap. These are the non-negotiables that have to happen in any training program. I'm referring to these in the strength and hypertrophy conversation, but these are true of power development, speed development, muscular endurance, endurance — any other goal. These are things that just have to happen for any training program to work.
My frequent collaborator Dan Garner will constantly say consistency beats intensity. The literature will show you very clearly that adherence is the number one predictor of physical fitness outcome. So we want to do something that you will engage in, put effort into, and be able to repeat consistently over time. That's number one.
The second one is a major reason that people don't hit their fitness goals. Outside of not doing it at all, the number one mistake they make is failing to apply progressive overload. I'm going to walk you through exactly how much you should be increasing your sets, reps, and weight per week and per month later. But that's the biggest thing — you have got to have some sort of overload. That's what's going to cause adaptation to continue to cause stress. If you want to see gains in strength and hypertrophy, you really need to progressively overload.
The third one is individualization. This is where we get into things like personal preference and equipment availability — whether you have kettlebells, dumbbells, bands, or nothing at all. These are smaller details, but they're an important component.
The last one I really want to get into is picking the appropriate target. If you run some testing and figure out where your biggest limitations are, that's going to help you identify where you need to go. If you can do all those things, you're going to be in a good spot to balance specificity and variation. If you want to make sure you grow your biceps, you better make sure your biceps are working. Having said that, if you over-rely on specificity, you're going to increase the likelihood of overuse injuries, which is going to hamper consistency over time. But if you go too far in the other direction — doing all kinds of different exercises every time you work out — that's actually not enough stimuli directly on the muscle or movement pattern to get you very far. This is the classic problem of doing a lot of work but lacking clear direction. Like in the business world, doing a whole bunch of different things means you get nothing really done.
Those are the concepts we absolutely have to hit. The methods we choose run across a handful of variables — we call these modifiable variables, because as you modify them you get different outcomes or adaptations. The way I like to say this is: exercises do not determine adaptation. You can't simply say "I want to get stronger, therefore I'm going to choose these exercises." What determines adaptation is the execution of the exercises.
A deadlift is my favorite example. People think of it as a lower body strength exercise, but a deadlift will not increase your strength unless you're executing it in the proper fashion — and I'm not only talking about technique. I'm talking about these modifiable variables. The same thing applies to power exercises. We commonly see mistakes with activities like a box jump. People think, "I'm going to improve my power" — which we know is extremely highly correlated to activities of daily living and particularly living unassisted as you age. But unless you do the box jump powerfully, you won't actually increase power. The way we manipulate these variables is everything in determining the adaptation you get, or don't get.
The 3-to-5 framework for strength and power
Dr Andy Galpin: Let's jump right into speed and power. At the onset, there's this 3-to-5 concept. I didn't develop it — it's just an easy way to help you remember one concept that will run true across all these things. 3-to-5 refers to three to five days per week, three to five exercises, three to five repetitions per set, three to five sets, and three to five minutes of rest between each set. If you do that and you execute any of the exercises you choose with high intent — and that part is critical — that allows you to run the gamut from as little as three days a week doing three exercises, three sets of three, which is a very low volume and a very low number of days, all the way to five sets of five of five exercises five days a week.
It's just one sample that's easy to remember and is quite effective for a very long time. This has been tested quite extensively in both the coaching and scientific realms to be quite productive and easy to follow. If you do that, all you need to do is slightly increase the load — or the volume, but mostly the load — over time. The number we want to look for there is something like a 3 to 5% increase per week.
Andrew Huberman: When you say 3 to 5 sets, that's 3 to 5 work sets, correct?
Dr Andy Galpin: Yep.
Repetition cadence for strength versus hypertrophy
Andrew Huberman: Is there a way you could lay out optimal repetition cadences for strength specifically versus hypertrophy specifically, and then migrate toward the middle in terms of rep cadences that would satisfy the desire to have a bit of both?
Dr Andy Galpin: When you're talking about strength versus hypertrophy, remember: strength is movement, hypertrophy is muscle size. That's the key to your answer here. When you're trying to get stronger, what you're effectively trying to do is get better at producing a certain amount of force through movement. Force is mass times acceleration — so the mass on the bar multiplied by how well you can accelerate it. Intentionally going slower is only reducing acceleration. It's hard to argue that going slower is going to improve strength because you're simply reducing acceleration. You need to practice lifting heavier at a faster rate.
Hypertrophy is not that. The goal is not a functional outcome — it's what is needed to cause the most amount of hypertrophy. When you get to hypertrophy, your optimal cadence is up to you. You can do any combination, and in fact you could use the exact same cadence as your strength training and get the same hypertrophy adaptations if you modify the other variables appropriately.
This is the 80/20 rule. 80% of the benefit is going to come from the concept, and 20% from these smaller details. If you're working with a qualified coach, there are lots of reasons to play with cadence. If you're on your own, a 3-1-1 or 3-1-2 cadence is fine. On the strength side, you just want to make sure you're under control and can add enough load to stimulate strength without getting hurt. On the hypertrophy side, you just want to load enough to hit volume, because you've got to put a lot in there. If you go slower in your repetition — say a five-second eccentric and a two-second rise — you can actually stimulate the same amount of hypertrophy with either less weight or fewer repetitions. So it's a variable you can play with.
If you don't have enough weight at home and your only option is doing more reps, that train runs pretty shallow eventually. Here's what you can play with: add time under tension. Do slower repetitions, longer ones, hold them. It's a tool we use to individualize programs rather than something you should be focused on as a core driver of whether your program works.
Exercise selection and variation
Andrew Huberman: For the person starting out, would you recommend they pick three to five exercises and stick with those so they can get their skill, movement, positioning, and breathing really dialed in, and then start to experiment by varying one or two of those exercises over time?
Dr Andy Galpin: That's great. If you look at the conjugate model — the strongest powerlifters as a collective group that ever existed — what they're very good at is keeping almost the exact same weekly structure but making a very small change in exercise variation. Say Wednesday is bench day. They're always going to bench on Wednesdays, but maybe this week they do close-grip bench, next week a special type of barbell, and the week after that they change the range of motion slightly. It's actually the same exercise with a very small variation. That change alone allows them to do enough specificity while also giving them enough variation so it's not the exact same stimulus in the exact same spot over and over. That's what allows that group to train very, very heavy very consistently without having to worry too much about periodization planning.
A major mistake people make is changing their exercises entirely way too often. If I had to pick one or the other, I would say don't change anything on your exercises for six weeks — probably realistically even 10 to 12 weeks — and then you can make some changes. It's going to take you about three weeks generally to figure out the groove of the exercise, to figure out how well you can load it, what's too much, what position works. It's going to take you three or so weeks, and then you can really start pushing. Changing exercises before that means you're not going to be able to progressively overload because you just won't know exactly where you're at. It's very important to create standardization and then see some progress before making changes.
Recap of key parameters for strength and power training
Andrew Huberman: Before we dive into hypertrophy, can we get a brief recap of the general parameters for an excellent power and strength training program?
Dr Andy Galpin: Let me hit you with these rapid fire. Remember those modifiable variables — let's go through them in order and what they mean specifically for power versus strength.
Modifiable variable number one is choice — which exercises do I select? For strength, power, or speed, we want to select compound movements. When we think about strength training, we tend to think about bodybuilding concepts — I've got to make sure I get my chest today, I've got to make sure I get my hamstrings. You're selecting exercises based on a muscle you want to work. For strength development and power, we want to think about movements rather than individual muscle groups. Things like explosive hip extension — a vertical jump — or pushing or pulling movements, or rotation, which is a whole area that's very important for overall health, wellness, and longevity. We want to select big movements by movement pattern and just ensure a reasonable balance between them. You don't want to go an entire six months without doing anything rotational, or eight to ten weeks without a lower body hinge. Think about upper and lower, push and pull, and some sort of rotation. If you're using the 3-to-5 method and picking as few as three exercises, just pick one from each of those groups.
The next one is exercise order. Because everything driving power and strength is quality-based, you want to do these at the beginning of your workout. No cardiovascular training, no repetition-to-failure work beforehand. If you do those first and you're now slower, all you've done is practice getting slower. You also need to do them when you're very fresh because they are the most neurologically demanding — they're complicated, often in multiple planes, and coordination is difficult. Any amount of fatigue is only going to compromise results.
The next one is volume. The general number we're looking at is something like 3 to 20 sets total per workout.
Andrew Huberman: Per workout?
Dr Andy Galpin: Per workout. Twenty would be a bit of a special case.
Then frequency — we've already indirectly talked about this. Frequency can be as high as you'd like in this area; it really depends on your recovery. If you're truly pushing maximum strength, you probably do need a few days to recover.
The last piece is progression. I mentioned this earlier, but just to fill the gap before we head to hypertrophy: aim for a 3 to 5% increase per intensity per week in general, and you can do upwards of about 5% increase in volume per week over time. I generally recommend running that for at longest eight weeks, but most realistically about five weeks, and then have some sort of deload or back-off week.
One last thing I don't think we did justice to is intention. We've talked a lot about specific loads you have to hit, and that's generally the case. But if intention is there, you can fudge those numbers in terms of how much load goes on the bar. In fact, you can get as low as no load on the bar. A great example is a plank. You could do a plank and simply contract the least amount necessary to hold the position. Or you could contract as hard as possible — pulling your scapula down and back, squeezing your core, squeezing your quads, squeezing your glutes. That is actually still going to help strength production because you're attempting to contract very, very hard even though the load is the same. That extends to weight on the bar. You could theoretically see large improvements in strength at 50% of your one-rep max if you're contracting as hard as possible.
How to induce hypertrophy: stimuli and programming
Andrew Huberman: Let's talk about hypertrophy. What are the ways that people can induce hypertrophy?
Dr Andy Galpin: A better way to think about that question is: what stimuli do I need to give the muscle to induce hypertrophy? There are hormonal factors that are important, and there are nutritional factors, but sticking with the context of training — this is really going to frame a lot of our answers, and it's one of the reasons why I call hypertrophy training kind of idiot-proof in terms of programming. The work is hard and difficult, but the precision needed is a lot less than what we saw in power and strength. With power and strength, it's very important that you do it in this style, with this intent, within these parameters — and if you're outside those parameters, it's not going to work. Hypertrophy has a very broad range in terms of actual applications. This is why you have, and will continue to see, countless styles of training that all work.
If we look at the classic framework, we basically have to challenge the muscle to need to come back bigger, and the nutrients need to be there to support that growth. All you have to do to not fail is make sure the training is hard enough. The only wrong combination here is infrequent and low intensity and low volume simultaneously. As long as one of those three variables is high, you're going to get there. Which is why crafting a program that's best for you is actually fairly simple when it comes to hypertrophy — you just have to make sure you do the work.
I also think it's important that you do some combination of what we call bilateral and unilateral exercises. Bilateral — think of a squat, where both feet are on the ground moving in sequence. Unilateral is one limb at a time — a rear-foot elevated split squat, a single-leg leg press, a single-leg curl, a pistol squat. This is also very important for making sure you're not getting any imbalances as you progress, especially through months and years of training.
Whether you want to pick specific implements — dumbbell, kettlebell, barbell, band, bodyweight — none of these things are as important, because all you're trying to do is create a certain insult in the tissue. The implement is whichever one you feel best doing, because of the way people move differently, their anthropometrics, their biomechanics, and even their technique.
The same exact exercise will not necessarily work the same exact muscle groups for multiple people. If you and I both did a back squat, and you did it in more of a high-bar style — bar sitting higher up on your neck, back more vertical, knees shifting further past your toes — that's generally going to put more emphasis on the knee joint and more work in the quads, with a little less work in the spinal erectors and back. If I were to do it in the classic low-bar squat — bar further down my back toward my shoulder blades, a slightly wider stance, driving my glutes back further from the midline — as a general rule, the thing that moves farthest away from the midline of your body is likely to be the thing that's activating the most. So in the low-bar squat, it'll be more low back, more glutes, and a little bit less knee.
That's a general statement, not always true, but as a guideline: if you're trying to improve a clear weakness in your quads and you're hammering squats and wondering why your quads aren't getting stronger or growing, it may be because of the style of the movement. Squats in general, if you look at the research, are an excellent exercise for quad development — but for you specifically, they may not be, because of the way you stand or because of neural activation. In that case, you may need to go to a machine and isolate that muscle group to make sure you see development there.
Don't assume that because the textbook says the bench press is good for your pec, it actually is for you. Depending on the angle at which your sternum sits in your body, a bench press may be doing very little for your pec, and you may need to adjust to an incline bench, a decline bench, or a pec fly. Machines can be fantastic at letting you isolate without having to worry about stability, your low back position, where your neck is — you can really concentrate on just the movement and the muscle and ensure you're getting training in that specific area.
Exercise order and body-part splits for hypertrophy
Andrew Huberman: What about exercise order?
Dr Andy Galpin: You get to play a couple of games here. When we talked about strength and power, I basically said stick to the big, most complicated compound movements first. You don't have to do that with hypertrophy. You can do the thing you're simply most interested in first. You can also do something called pre-fatigue. Say you're doing a back day — you could go in and do nothing but isolated biceps as your very first exercise and then roll into your pulling movements. During most pulling activities, the biceps are a secondary or tertiary muscle group, but you've pre-fatigued them. You've guaranteed that the muscle of most interest got its most training in, and everything else is secondary. So you can start with single-joint movements, isolation work, or compound work — it really comes down to preference and what you're specifically trying to develop.
This also goes back to the exercise choice question, and where I wanted to cap this was the exercise splits. A question I get a lot is: which muscle groups should I package together? I'm not really concerned with it. All you should worry about is how many times per week — and in fact total volume — you achieve on a muscle group per week. It doesn't really matter how those things are folded in; it's really a personal preference issue.
One mistake we commonly see is grossly underappreciating that the legs are not a single muscle group. The legs have a whole bunch of muscle groups in them. We see a classic split like chest and shoulders Monday, biceps and forearms Tuesday, legs Wednesday, then back to upper body — and you realize you have four days dedicated to the upper body and one for "legs." Over time, you're going to do far more upper body than lower body, and that's not appropriate. Think about your lower body the same way you would any other body part split, and don't just chunk everything in as "legs" once a week. If you want to do that, that day has to be very, very challenging with quite a bit of volume, because you're almost surely not going to hit the total weekly volume needed to optimize muscle growth if you're literally only training your lower body once a week.
Volume requirements for hypertrophy
Andrew Huberman: Along those lines, let's talk volume. How much volume does each muscle group need per week in order to generate — and for that matter maintain — hypertrophy?
Dr Andy Galpin: The minimum number we're going to look for is 10 working sets per week.
Andrew Huberman: Per muscle group?
Dr Andy Galpin: Correct. Ten would be sort of the minimum. The more realistic number for most people — especially if you're advanced or even intermediate — is more like 15 to 20 working sets per week. If you're very well trained, you probably want to push toward 25. Past that, there's just not a lot of research.
If you did three sets of 10 repetitions three days a week, you're already at nine — basically at your minimum. If you went to the gym one day a week and did three sets of 10 for three exercises, you're at nine working sets, basically done. So achieving 10 sets per week per muscle group is not that hard, and we're not even counting indirect activation from secondary muscle involvement. Hitting 20 is actually still not that hard.
However, if you're not seeing adaptations, the repetitions may not be challenging enough. If you do a set of 25 and at the end you're thinking "yeah, that was kind of starting to get hard," that's not going to be enough. If you do a set of five or six with the same expression, that's also not going to be enough. In that case, it doesn't matter your rep range if you're not getting somewhat close to failure. It doesn't need to be complete failure — a good number to think about is "minus two," which is what we call reps in reserve: you got within about two reps of failure and then stopped.
You have a lot of room to adapt based on your circumstances. If you're short on time — your workout typically takes 60 minutes but today you've only got 35 — and you're training for hypertrophy, you need to make sure you hit that total volume. In that case, lower the load, lower the rest intervals, and just get to the burn and get as much done as you can. If you're training for strength, I would rather you cut your volume in half, get those few repetitions done at high load, and just not do very many sets today. That's a better result.
The goal you're going after is going to determine what we call chaos management — running out of time, not feeling it today, being in a hotel, and so on. That's going to be 10 to 50% of your workouts. That's life.
Frequency and workout duration for hypertrophy
Andrew Huberman: I'd like to ask about frequency, but I'd like to frame it a little differently. I'd like to ask about total workout duration, which dovetails with frequency, because if one is hitting the appropriate number of sets per week and combining different muscle groups on the same days, workouts are going to be a very different duration than if one is doing a different body part each day. Any discussion about frequency has to be within the context of workout duration and vice versa.
Dr Andy Galpin: If you are a lifting junkie and very consistent in your schedule, I'm actually okay with body-part splits. Most people are not that. The concern is that if you're isolating and waiting to do your glutes on one specific day of the week and something happens on that day, you might go another 13 days before training that muscle group — and that's really difficult to maintain. The frequency won't be high enough unless the load and volume on that one day is astronomically high.
While the research shows that frequency in terms of days per week doesn't matter that much as long as total load and proximity to failure are equivalent, practically it's a challenge. Life gets in the way for most people, especially if you have kids and a job. So I actually prefer something more like three days a week of total body. If something happens, you've just missed that body part for 48 to 72 hours. I like that a little better for most people — not because it's more effective, but because it's a little more resilient to life.
If you wanted to do a combination — say two days a week of whole body and two days a week of a little bit of a body-part split — you're actually hedging against all risks, as long as you get to that total weekly volume.
There is actually some evidence that a little bit more frequency may be slightly better. But the difficulty is the practicality question: how many people can really do strength training six days a week on top of their long-duration cardio, high heart rate work, flexibility, and everything else? It's just really, really hard to get all that in. It tends to be easier on folks in terms of execution and long-term adherence to get that volume accomplished in a more frequent pattern — but not once a week. I'd like to keep it right there for most people. Again, not because it is technically more effective, but because you're less likely to fail to progress due to skipping a workout or something coming up.
Andrew Huberman: Great. Thank you for that very informative answer. This was incredibly informative. Thank you so very much.