Reps Per Set for Optimal Growth
I’m going to throw out a weird hypothetical question that I want readers to consider before continuing with this article.
If you had to pick a single repetition range to train in for growth, what would it be?
That is, imagine some very strange situation where you could only train within a certain range (and let’s make that range something a little less vague then ‘Between 1-20 reps’ by limiting it to a 3 rep range) for the rest of your lifting career, what would it be?
I used to ask this of friends of mine in the field and, almost with exception, the answer was pretty much the same. This was true regardless of whether or not they had arrived at that value from experimentation and experience or just looking at the research.
I’m going to take a quick look at the research (including a bunch of seemingly disparate topics) to tell you what I’d pick.
What Makes Muscle Grow?
I asked a job supervisor that question once once; he was a smart-ass like me and told me “It needs lots of sunlight and water.” Close but not quite.
The mechanism of muscle growth has been under heavy scrutiny for years and a lot of theories and ideas have come and gone in terms of both the mechanism of growth as well as what stimulates it. Semi-amusingly, about 98% of the actual answer was known back in the 70′s.
In an exceptional paper (which I recommend the reading of to any nerds in the field) titled “Mechanism of work induced hypertrophy of skeletal muscle” a researcher named Goldspink pretty much laid it out concluding that:
It is suggested that increased tension development (either passive or active) is the critical event in initiating compensatory growth.
Basically, the development of high levels of tension within the muscle is the key factor in initiating the growth process. I’d note that there are also some elements of fatigue that may be contributing to what ‘turns on’ the growth response. Finally, I’d note that in order to keep stimulating growth beyond an acute training bout, there has to be an increase in tension. Basically, over time you have to add weight to the bar.
Which as another great scientist in the field (Ronnie Coleman) summed up thusly:
Everybody wants to be a bodybuilder, but nobody wants to lift no heavy-ass weights.
The simple fact is that, outside of heavy drug users (steroids having the capacity to stimulate growth without even training), the biggest bodybuilders are the strongest. They grow because they provide, over time, a progressive tension overload (of course there are more variables that go into this, total workload per workout, frequency of training and diet all interact here).
But as I have been pointing out for years and years and years, if you’re not adding weight to the bar over time, you’re simply not growing. You can focus on the feel and the pump and the squeeze all you want; if you’re using the same weights 6 months from now that you’re using today, you won’t be any bigger.
Which doesn’t mean that you have to add weight at every workout (the fallacy of HIT), simply that over time you have to be lifting more weight. But progression over time is a whole separate article.
Anyhow, the summary of this section is that a combination of tension overload (with a possible contributor of fatigue) within skeletal muscle fibers is what turns on the growth response. Just remember that, what stimulates growth is tension and fatigue (with tension playing a relatively larger role in terms of actual contractile growth).
Which brings us to the next question: what’s the best way to develop that combination of tension and fatigue within skeletal muscle (or a given fiber)?
A Quick Tangent into Some Neurophysiology
When you look at strength production, the body has essentially two methods to increase force output which are
- Muscle fiber recruitment
- Rate coding
Muscle fiber recruitment is exactly what it sounds like, how many of the fibers within a muscle are actually being recruited. Contrary to the exceptional silliness which is endlessly repeated in books and on the internet, most people can actually get pretty close to 100% fiber recruitment (it’s a little bit lower in the lower body but, in the triceps for example, people can get near 100% recruitment).
Rate coding referes to how quickly the body is sending electrical signals to that muscle. As rate coding goes up, the muscle fires harder.
Now, in the muscles we’re interested in from a sports or bodybuilding standpoint, the body will generally use recruitment to increase force production up to about 80-85% of maximum force output (in the lab, this is measured with Maximal Voluntary Isometric Contraction or MVIC, which is effectively 1 rep maximum weight). Beyond 80-85% of maximum, it uses rate coding.
I’d note for completenes that this isn’t true for some muscles in the body, notably stuff like the eye muscles and finger muscles. In those muscles, recruitment is used up to about 50% of MVIC and rate coding handles the rest. Which is a lot of why studies looking at the thumb muscles aren’t really relevant to most training applications. But I digress.
Anyhow, now we have the next part of the picture, the body will recruit more fibers up to about 80-85% of maximum; above that point, there is no further recruitment and force output is improved via rate coding.
I should note that even at lower intensities, as the individual goes to fatigue, eventually all muscle fibers will end up being recruited. But they won’t have been recruited until fairly late in the set (e.g. the last few repetitions).
Putting it Together
And this leads us to our answer to my original question. For most people, 80-85% of maximum is roughly 5-8 repetitions there is variance in this between individuals and perhaps muscle groups (for example, some people find that they can get 12-15 repetitions at 85% of maximum in some leg movements).
Now let’s put that together with my comments about tension and fatigue from the earlier in the article.
Imagine that you put 95% on the bar, which will let most people get about 2 reps. You wouldn’t increase fiber recruitment (remember, it maxes at 80-85%) but you would drastically decrease any fatigue because you would be getting a lot less reps per set (and most people couldn’t do many sets of 2 at 90% so their total volume per workout would be much lower).
Or say you wanted to do 15 repetitions which, for most is about 70% of maximum. If you take it to failure, you will in fact end up recruiting all muscle fibers; however many of them (and this especially holds for the highest threshold fibers, the ones with the potential for the most growth) won’t have been recruited until near the very end. So those highest threshold fibers won’t be exposed to high tension and fatigue for very long.
In contrast, imagine that you work in the 5-8 rep range with 80-85% of maximum. First and foremost you will get full muscle fiber recruitment from the first repetition. Secondly, you will maximize fatigue/metabolic work/volume within that range. Basically, that range of reps and intensities is the one that will give an optimal balance of tension/recruitment and fatigue/metabolic work.
And that’s the answer that repeatedly comes up among people in the field who aren’t clueless: 5-8 repetitions. If you had to pick a single rep range to work at to optimize the growth response, it would 5-8 reps per set.
Which isn’t to say that there aren’t valid and valuable reasons to work in other repetition ranges, mind you. But that wasn’t the original context of my weird hypothetical.
sweet.
that was my guess.
Lyle,
This was an excellent piece. As always you have a knack for perfectly blending the esoteric and the commonplace and leave people saying, “But of course!”
While I am not doubting the fact that his methods likely work well, since the best workout is always the one you haven’t yet adapted to, does your comment about MU recruitment being maxed out (in most muscles) around 85% of maximum contraction and rate coding being responsible the rest of the way indicate that Chad Waterbury’s system of selecting total target rep ranges and not focusing on the number of sets but rather the speed of each rep is somewhat overrated compared with a more traditional approach of selecting a rep range like 4-6 or 6-8 and using a specific number of sets?
Obviously you don’t want speed drastically slowing on multiple reps per set, but I’ve never found this to be an issue using a specific number of sets if proper loading and technique are respected.
Thanks for the article!
[...] fallacy of combine training (the bench press), injury from doing too little, rep range for growth response, exercise actually *gasp* helps joints (real and fake alike), interpreting body composition [...]
Ideally I would vary between 4-6 reps and 8-12 reps for 6-12 weeks at a time. But if I had to choose only one range – I would go with 5 to 8 reps like you.
8 was my guess.
Say you do 5 sets and you are getting tired on set 4-5. Do you lower weight to stay in the range or reduce the amount of reps and stay at the higher weight?
I didn’t really understand what you meant by ‘rate coding’.
I tried to look around the net for clarification, but that only made me more confused.
If all the muscle fibers are recruited, how does a greater frequency of electrical impulses to the muscle make it fire harder? I’m not even sure I understand what you mean by harder?
Do you know any good links that explain this process in laymen terms?
Cheers
Great article. FWIW, my best gains in muscle mass have always been from 5-6 sets per muscle group within the 6-10 rep range. For upper day I would usually start out with 3 sets of 8-10 on dips, do the same with chins, then go to3x6-8 on flat bench and the same with rows.
Leg days were similar with squats, RDL’s and leg presses.
As Ronnie would say ‘Ain’t Nuthin but a Peanut!’
I’m no expert, but I’ve been led to believe there are two types of muscle hypertrophy: sarcoplasmic (basically fluid, not much to do with strength) and myofibrillar (stronger fibers, but not much volume).
So an athlete who wanted to be very strong, but in a certain weight class, he’d want to avoid sarcoplasmic muscle growth and do his best to gain myofibrillar muscle growth, which would mean using a weight very close to the 1RM to target maximal strength. But bodybuilders, who just want the biggest muscles, would be better served going to higher sets (more like 8-12) and be happy with not much strength gains but fluffy muscles.
If this is the case (and my understanding of this stuff isn’t totally mangled), is the 5-8 rep range is how you’d target both types of hypertrophy in a set, and therefore maximize growth?
Great article. If doing this 5-8 rep methodology, how many sets do you recommend, and also how much of a rest period between a set if the goal is hypertrophy?
This goes for abs too?
Thanks for this article–kind of explains to me some of the stuff you were talking about over at the forum.
Joe: Chad Waterbury has never had a clue what he was talking about. Slowing of rep speed is irrelevant and you will only recruit more fibers as you fatigue. the idea that you must train fast to recruit the fastest fibers is simply nonsense.
Ezekial: How to handle sets within a workout is one or two articles itself.
Kira: Rate coding is literally the rate at which neural impulses travel from the brain to muscle. As rate coding increases (up to a point at least) so does force output. I can’t explain it any better than that.
Jonny: Some sources say there are two types of hypertrophy, others do not. For sarcoplasmic hypertrophy, the primary stimulus is fatigue and energetic depletion so you’d use much higher reps.
Ankit: Different article, I’ll talk about total workloads at a later date.
Omar: Abs are a muscle like all the rest. Train them like any other muscle group.
Lyle
Your answer seems to be premised on gaining strength as the goal. But what if you want to gain strength and stimulate weight loss, or at least minimize fat gain? I was under the impression (and my anecdotal evidence seems to bear this out) that slightly higher reps can help stimulate the metabolic effect of the workout better. Put simply, even with no changes in diet, I seem to get fat off of low-rep routines.
Jeremy
The title of the article was:
“Reps Per Set for Optimal Growth”
Not strength, not fat loss. Because if I had been writing about either of those, I probably would have called it something else.
Lyle
Lyle,
In your old article ‘periodization for bodybuilders pt 2′, u mentioned, “Intensive bodybuilding method: 4-6 reps @ 80-85% 1RM. Extensive bodybuilding method: 6-12 reps @ 70-80% 1RM ” Have things changed slightly or am i worrying too much?
Ok, I’m going to really try to not get screamy but I want you to go read the article again and the hypothetical question I posed at the start of it.
Here, I’ll reiterate it
“If you had to pick a single repetition range to train in for growth, what would it be?”
Now I’ve bolded a key word in that sentence that explains the confusion you’re having.
Put differently: in practice there’s no reason you’d limit yourself to a single rep range. Which is why I made sure to start this article by explaining my weird hypothetical question.
In practice, you will use different rep ranges (either in the same day or different workouts).
Lyle
@KIra:
In order to make a muscle contract you nervouse system sends pulses to your muscle. A single pulse leads only to a very short contraction. In order to get what looks like a constant contraction you nervouse system sends a lot of pulses (something about 50 pulses per seconds).
So a contraction of a muscle fiber actually consists of a lot of mini contractions. The next contraction starts before the muscle completely relaxed from the previous contraction.
In order to generate more force the frequency of these pulses can be increased to – I think – about 120 pulses per seconds. The mini contractions overlap even more and as a result more force is produced.
Is the ideal rep range assuming a single set? The reason I ask is that if my 8 rep max is 80%, my three sets of 8 max is probably less than 75% which would fall out of the ideal growth percent. If you are looking for a volume of more than 8 reps, wouldn’t the ideal rep range be more like 3-6? What kind of volume do you generally recommend in the 5-8 rep range?
IIRC the IART (Bryan Johnston (sp?)) idea is to test each exercise at 85% of 1RM and use that rep range for most sets as opposed to a cookie cutter 5-8 rep average. Seems to work well for me; I can do @5 reps with 85% for pecs but about 10 for tris, for example. Quads are higher still…
How would that translate to TUT instead of reps? When talking about time under tension, we’d have to test 1 RM with the same rep tempo we wish to use for training, right?
I am simply wondering about this and the thought of muscle confusion, do they correlate?
I’m not very expert but I like training a lot!
I think your article is very interesting and well written.
Thank you!
Hi Lyle,
I hope linking to websites is allowed in your comments, as I am certainly not self-promoting or anything, but just wondering what your thoughts are on this particular article (Link: http://www.tmuscle.com/readArticle.do?id=1764218), which states:
2-3: strength with little size gain
4-5: strength and size gains, but more strength than size
6-8: strength and size gains, almost equally
9-12: strength and size gains, but more size than strength
13-15: size gains, and some muscle endurance gains
16-20: muscle endurance gains, and some size gains.
How much of that is factual?
Eagerly awaiting your response!
Jono,
An element of truth, an element of gibberish.
You can grow on low reps if you do enough sets and Ol’ers rarely go above 5 reps per set and get pretty decent legs (and sometimes upper bodies). And you can gain some strength with high reps.
Lyle
I’m afraid Joe has misinterpreted Chad. Chad recommends that on each rep you attempt to accelerate the bar as fast as possible in the concentric phase – maximal voluntary muscle contraction! and by doing so you can recuit near 100% muscle fibre even at sub 80-85% loads. It doesn’t matter about the speed the bar is travelling at, what matters is the attempt to move the bar as fast as possible on each rep in order to get the most out of each rep. Why recruit 100% of muscle fibres only at the end of the set when you begin to fatigue when you can do it from rep one by applying as much force as you possibly can regardless of the loading?
What Chad actually recommends is stopping the set when you lose the ability to perform a maximum voluntary contraction – nothing to do with speed, and this is were Chad differs from other coaches.
There are alot of olympic lifters, powerlifters, bodybuilders and coaches all of whom recommend performing the concentric as fast as possibe and with good reason – muscles like it be it for increasing size and or strength
Beside this tab on my browser i’m reading another article mentioning something that the author calls post-activation potentiation – where by some neurological adaption, you’re able to perform reps more easily if beforehand, you lift heavily for one or two reps (over 85% of your 1RM). I guess this is true… a lot of people must know what it’s like to perform pushups after a heavy set of bench pressing, or dips.
What i’m wondering/asking is whether this is a good way to ‘enhance’ muscle growth outside that 5-8 rep range with every workout?
Such as (after warm-ups) performing 1 rep at 95% of your max, resting a minute or two, lifting within 5-8 reps, rest, then repeat until fatigued? Could it hinder results?
After reading about it I figured that since the CNS is responsible for the number of motor units recruited when activated, this might be a smart way to train muscle groups.
PS. I’m no sport scientist, you could probably say that my gappy knowledge is recycled from months of googling and ebooks. When I started reading your articles i’ve seemed to straight out a lot of my problems with training and diet though.
The Warming Up for the Weight Room series talks specifically about using a heavy single above the day’s work weight for essentially this purpose. Certainly there is something to the idea of PAP.
1. How much strength can be gained without hypertrophy? as in with purely neural adaptions? and i read that low reps with heavy weight is the way to go to achieve this?
2. Is it the neural firing rate you refer to what is becoming more efficient when people talk about neural adaptions?
3.you say there is evidence to show two types of hypertrophy and also evidence against it? surely we must know this by now? do you side with this theory?
thanks dan
Lyle,
Great article, as (almost!) always.
I picked 5-7 reps at the beginning of the article. Glad to hear most experienced lifters would agree (my first choice was 6 RM, but since you asked for a range, I went for 5-7).
What do you think of the good ‘ol 8-12 rep? Most training books say it’s the best rep range to build muscle… and it’s even backed by some research by Kraemer and friends who found that sets of 10 with 1:00 in between triggered the most anabolic response.
Curious to know your thoughts on the 8-12 range.
Best,
Carl
Lyle
Great article!
I get so tires of having this age-old argument with everyone I run into. I feel 5-8 reps is ideal for maximal muscle growth along with strength gains.
I personally experiment with a 4-month phase of high reps per set (12+) for 5-6 sets. It gave me crazy pumps and that sick Greek god look… BUT 1hr after lifting I deflated!!! Lots of sarcoplasmic growth and very little strength gain.
My advice to all fitness enthusiasts looking for solid hypertrophy:
- Lift hard and heavy
- Majority of lifts should be less than 10reps per set
- Focus on slowly loading the eccentric phase (ex// lowering the bar during a chest press)
- Explode through the concentric phase (ex// pressing the bar during a chest press)
I’ve seen a lot of guys become bogged down in the “science” of body building and their routines suffer from overthinking ideal rep/set, total reps per group, time under tension, etc.
Keep up the great work!
As I get older injuries have increased to tendons / ligaments and joints as i am very small boned. is there any way of appreciably strengthing tendons? my understanding is due to lack of blood supply tendon injuries take ages to heal. for the same reason i doubt much can be done to strengthen them. your thoughts???
For the most part, it’s probably an issue of time. Connective tissues are very slow to adapt but they do adapt. The idea that isometrics preferentially strengthen tendons has been bandied about in the strength training literature for decades; I can’t recall having seen anything to support that but I can’t honestly say I’ve looked exhaustively. Folks with lighter frames often do better staying at the higher end of the repetition ranges (lower rep work simply being too much) or need to cycle intensity more to avoid causing problems.
Lift heavy weights fast…..or try to lift them fast. Slow and controlled lowering of the weight. I love 4-6 or 6-10 rep ranges. Good article!
Thanks Lyle. Been a personal Trainer for 4 years and just questioned the logic of the 12×4 formula for hypertrophy for the first time tonight…shame, shame, shame. I hate that 12 – 15 rep shit! bring on the heavy!
Very nice article! But how many sets are we talking about? 5×5, 6×4, 8×3, for example?
At last! Practical fitness advice backed by sound science. I’ve learned more in the last 5 articles than in 2 years of reading “The latest study suggests…” articles. If I hear the words “whole grain” one more time I’m going to stick a fork in my eye! Excellent work Mr. McDonald. Passing along this info to others as well. Thank you so much.
1.I used very high rep training (25 per set) at 135 pounds-all that was available to me at the time,and became extremely strong and fit.my 1 rep max when done for the bench ,later on,was 305 pounds.2 As far as protein the rda is spot on.
Nice article Lyle. Informative. Many folks here have raised a question again and again..on the optimal set/rep numbers. I would say 5 by 5. I would also direct them to a website http://www.stronglifts.com which is ALL about this.
I have been into this program for sometime and i would want people to know more about it.
Thanks Lyle..good job on your part on explaning things which would have otherwise been considered as arcane by laymen like me
cheers
Ramesh EMV
Protein synthesis is maximally spiked from 75-80% of the 1rm. It doesn’t matter if the you engage all fiber from rep one vs 2 reps into the set…the overall volume greater with a 10rm load vs a 6 or 8rm.
Protein synthesis is what builds muscle, not fiber recruitment from rep 1.
Huh?
Hi Lyle,
What do you think of this interesting study:
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0012033