I’m often asked about the relationship between repetitions, volume, and building muscle. I used to kill myself over matters like this. I used to worry about whether five reps (or maybe six reps!) would be my golden ticket. I’ve since relinquished most worry because I’ve adopted a certain worldview. Below is the meat of this worldview, followed by some equally as meaty takeaways.
How muscle is built
First, if you’re caught up in this, you’re over thinking things. To this day, no one really knows how muscle is created. There are theories. But before you get all sticky in the theories, ask yourself: why do you care? There are a lot of people that learn how to build muscle without knowing the sloppy details (ahem, “theories”) of muscle building.
Go to any gym in your area. Even terrible gyms, like Planet Fitness. You’ll see a lot of meatheads with muscle. They won’t be able to tell you the first thing about a sarcomere. (I don’t know if I can tell you much about a sacromere either.)
There’s a difference between the phenomenology and the phenomenon. Find the latter. The list of theories on muscle growth grows with time. There exists caveats with each explanation. You can listen to ideas of micro-trauma via weight-training and whatnot, but there are no lions and gorillas pumping iron and worrying about microtrauma.
Trying to hack the human body requires first accepting (that is, unless you’re trying to be a con artist and trying to fool others into buying the next gimmick) that there are more causal factors affecting any given outcome than we typically attempt to fathom. See emergence. See reductionism. We try (unsuccessfully) to peg muscle building down to one thing, but it’s rarely one thing.
What do we know? I’m a fan of empiricism. That’s my backbone. So we’ll start with some consistent observations. We know that astronauts wither into nothingness when living in the vacuum of space. Their bone density and muscle tissue plummet. So there’s something about the stress of gravity and gravity-esque stress that appears to support muscle.
But we also know gravity isn’t the lone factor enabling muscle growth. Otherwise women and men would have the same muscle mass on average. Not the case. So you dig further. Hmm, hormones. Yeah. Those seem to impact things. Then dig further and understand that food impacts hormones, so there’s nutrition to consider.
Already I’ve introduced three factors impacting muscle growth. And if I can playfully borrow, from physics, the three body problem: when more than two things are involved in a system and you’re trying to predict outcomes, get a pocket protector, stop going to the gym, get some glasses, and become a full time scientist. Because that’s your only shot at making a prediction.
Muscle mass, to me, isn’t sets or reps. Overtly, at least. It’s nothing glamorous that can exist on an enticing blog headline (accompanied by a number, creating a listicle). Muscle mass is, instead, a manifestation of an existence that demands the creation of muscle mass. And then giving the body what it needs to support the investment.
If living in the vacuum of space eats muscle and living on Earth vomits muscle, then its best, if you want to be even more muscular, to live on Jupiter. Barbell and bodyweight training are the best gravitational replicators. Maybe you knew their power. Good. Still doesn’t solve the set and rep quandary. But it’s not supposed to.
Think of existing on Jupiter. Dealing with a constant stressor. The Soviets (just about all worthwhile sports science was born here, and most western studies simply regurgitate what has already been known for decades) found one thing correlated to muscle growth more than anything else: volume. And volume is (SETS x REPS x WEIGHT). What kind of training allows you to accumulate the most volume? Something that’s of decent enough weight that you can do for decent enough reps and repeat for decent enough sets.
Muscle building formula
Ambiguous, right? Perhaps this is more hardcorely put by Dan John, who might have stolen it from someone else (I can’t remember): the answer has never been high reps for low weight or low reps for high weight, it’s always been high weight for high reps. You need a combination of stress and volume. For stress, think relative load. More weight = more stress. For volume, think reps across a training session (or even week), not necessarily reps in one set.
Ultimately, the closer you train to your maximum (and thus, lower reps per set) = better for the grand stimulus. But training at 1RM intensity isn’t sustainable. You can’t accumulate a lot of volume.
- Too heavy = can’t accumulate a lot of volume because you’re held back by sets and reps.
- Too light = can’t accumulate a lot of volume because you’re held back by weight.
Being cliché, there’s something to the 5-10 repetition range that seems to be an ideal blend. But get away from repetitions and all that jazz for now. Go back to Jupiter. Think of two things: (1) being able to exist shortly within the higher stress environment, (2) being able to tolerate for a longer time the higher stress environment.
- Higher stress environment = better.
- More tolerance within said stress = better.
So the higher your strength, the better. But, also, the more you express that strength, the better. There are two ways to express the strength:
- Strength-endurance = many sets in one session without much rest between sets.
- Strength-tolerance = ability to express strength at a high frequency.
I’ve seen some of my best muscle gains doing high frequency training (strength-tolerance). It bridges the gap between strength-endurance and volume, in my eyes. For instance, people often forget, unless you can crank out 20+ consecutive chin-ups, you’re often working with, say, a 15RM doing just bodyweight chin-ups for a set of 10 reps.
Where a lot of people may be able to do one set at 10 reps, they may not be able to do 2, 3, 4, or 5 sets without gnarling into a ball of fatigue or taking serious breaks in between sets to finish the workload. So if you’re trying to accumulate more volume, you’re probably better off spreading the workload across multiple sessions. Maybe do 2 sets of 10 chin-ups three days per week instead of 6 sets of 10 chin-ups one day per week.
Of course, this ignores the fatigue and metabolic accumulation that happens when condensing the workload into one session with minimal rest in between sets vs. condensing the workload into one session with generous rest in between sets vs. spreading the workload across multiple sessions. The absolute adaptations in each scenario won’t be the same. Just like eating 5000 calories one day and 0 calories for four days won’t be exactly the same as eating 1000 calories for five straight days. But I feel that most biological questions are filled with more uncertainty than we tend to estimate.
I think the muscle mass should be seen in flux, like the rest of the body. Sometimes not caring about muscle (or losing muscle) can be the most powerful way to eventually trigger muscle building. Sometimes boosting neural abilities can help future muscle building pursuits. Sometimes boosting metabolic…
…you get the idea. Emergence. Everything is connected in ways we probably can’t fathom, and in ways we are probably hurt by trying to fathom. So let’s get to some meaty takeaways.
A. You need to give your body reason to build muscle.
Beyond what’s going to get programmed with Earthly gravity stress and being human, you need to signal for the creation of more muscle mass. There are two facets of this: stress (higher gravity, AKA more weight to overcome) and volume. So I’d say anyone stronger has the potential to be more muscular.
And then beyond strength, the next qualification is expressing said level of strength frequently. And to calculate “frequently” you’re probably best looking at SETS x REPS and considering the weight used in relation to your 1RM.
B. 20RM to 10RM.
Save for edge cases, I’d say training with a weight that’s between your 10RM and 15RM is the way to go, with your 10RM being a weight you’re going to chuck multiple sets of 5’s with and your 15RM being a weight you’re going to chuck multiple sets of 10’s with.
You can extend to 20RM for edge cases, methinks. Anything lighter and you’ve extended beyond the realm of traditional strength training, perhaps into the realm of slow-twitch protocols. But I wouldn’t worry about those until you’re already plenty strong and muscular and thus probably not asking this question to begin with.
On the other end, it’s not that anything heavier can’t be of use. It can be. But you then have to do many many sets, which can become about as fun as smashing your head into a wall until it bleeds. It can also be rather aggressive on your joints and your body.
C. Consider food.
Energy can’t be created or destroyed. If you want your body to fathom more tissue, your body has to get the materials from somewhere. If you aren’t eating more food than you need across an extended period of time, then your body won’t have the supplies needed. Your body isn’t going to break down and sacrifice your internal organs in the name of building muscle. Muscle is extra. Plumage. It’s like a boat. You only buy a boat if your basic needs are covered and you have some extra cash.
D. Don’t give yourself the chance to care.
Getting into behavior economics has impacted my training more than any anatomy, physiology, or sports science book. I’m an overthinker with the inability to make decisions and the propensity to be handcuffed by choices. And so something I strive to do more and more: eliminate my chance to choose.
Back when I was trying to create programs for myself, I made it easier by storing all of my equipment away save for a barbell and gymnastics rings. This forced me into hammering away a handful of exercises.
If obsessing over sets and reps is destroying your progress (not feeling confident, always changing and looking for something magical) then here’s what you do: eliminate your choice to care.
We’re a product of random rules. Convention. We have plates of certain weight for no good reason, save for it helping Olympians lift one more pound than the next goober. What if you created a kind of training atmosphere that demanded you go through times of both high repetitions and lower repetitions?
A lot more guys (me included) would be better off playing the 10-25-45 game, which is another Dan John thing. You either add 10’s to the bar, 25’s to the bar, or 45’s to the bar. This forces you make harsher jumps and train both with a weight you’re less comfortable with for low(er) repetitions and with a weight you’re more comfortable with for high(er) repetitions.
Given the advice above, there are some final guideposts.
- For Level 1 n00bs, getting stronger (handling more weight on the bar) is the way to go because strength allows you to accumulate more volume.
- Those that want to get strong without gaining muscle should be mostly worried about keeping volume to a minimum.
- There’s not as much of a dichotomy between strength and muscle mass as most people believe. There are some differences, philosophically, when training solely for muscle. But that’s a conversation for another day.
- There’s an inverse relationship between training frequency and volume per training session. More volume in one session = more fatigue = more rest needed. So if you train a movement pattern less often, you need to do more sets to hit the needed volume.
And I’m sure there are more things I’m missing. This started out as an email reply and blossomed into this essay you’re reading now. Hopefully it’s helpful. When it doubt, think gravity + tolerance. More gravity = better. More tolerance (via reps, sets, frequency) = better. I don’t know if it needs to get more complicated.