Previously I have written about training intensity and frequency and, in that vein, I want to talk about training volume. I’ll be focusing on the weight room and, as much as anything, this is hopefully a background article for something longer I might actually eventually write. As with my article on intensity, what I will primarily be doing is looking at some of the different definitions of volume that are out there along with pros and cons of their use.
The FITT Equation
In the realm of exercise, one of the oldest used descriptions of training is usually called The FITT equation (I believe it’s been expanded in recent years). The letters stand, respectively for Frequency, Intensity, Time and Type. Let me define each but reverse the last two.
Note: Yes, I know that T T has no implied order except that it was always described as Frequency Intensity Time Type so I am technically reversing them.
Frequency is simply the number of times per week training is done. This can refer to total number of sessions per week, the total number of sessions of a given type of training per week, the number of times a given muscle group or exercise is trained per week and others.
Intensity is the effort level at which training is done. In aerobic training it can be defined as a percentage of maximum heart rate, a percentage of VO2 max or some threshold, etc. In the weight room it can be set by percentage of maximum (or some sub-maximal RM), Rating of Perceived Exertion (RPE), Reps in Reserve (RIR), Reps to Failure (RTF) and others.
Type is just the kind of exercise being done. This one is pretty self-explanatory. Running, cycling, rowing, weight training are all different types of exercise.
Time refers to the duration of the training. This has a lot more meaning in endurance activities which tend to be fairly continuous (i.e. 45′ of aerobic exercise). It has a lot less meaning in the weight room where saying someone did one hour of training doesn’t mean much.
A bodybuilder doing 25-30 sets on a short rest interval isn’t a powerlifter taking 5-10′ between maximum sets who only does a handful of low repetition sets even if they are both in the gym for an hour. And both think that the other is training wrong.
But that leads right into the topic of training volume.
A Generic Definition of Training Volume
Arguably a better term to use than “time” to describe training would be to use the word “volume”. In this sense, volume refers simply to the total amount (i.e. volume) of work being done. And I think it acts as a much more general and applicable term than time per se.
So if an archer takes 20 practice shots in a day, their volume was 20 shots. How long it took is immaterial.
If a shotputter took 15 practice throws, their volume is 15 throws. How long it took is immaterial.
For plyometric training, volume is usually defined by foot contacts or landings or whatever.
In soccer, volume is defined as number of flops per half or period or whatever they call it over there.
Certainly in endurance sports volume could be defined by either time or distance. And arguments can probably be made for both. Two runners who ran 3 miles ran the same volume in terms of distance.
But if one did it in 20 minutes and another did it in 40 minutes, their volume as defined by time is totally different. But so is their running speed, etc. This isn’t the place to quibble about whether the duration or distance is the driver on the training effect.
As I think about it, typically when you see aerobic recommendations being made for health or what not, it’s almost always in terms of duration. Do 30-45′ at a heart rate of 70% of maximum or whatever.
When endurance athletes talk about their training, it’s almost always in terms of weekly or monthly mileage (or I guess yardage in the pool). Cyclists love bragging about their 400 mile weeks and runners usually gauge their runs by distance rather than time.
Which brings us to the weight room and the actual topic of this article. Where the question of how to define volume becomes a little bit more complex.
Or rather how to accurately define volume becomes more complex.
Before getting to that, a question.
Why Does Volume Matter?
I guess a tangential question to address is “Why does training volume matter?” Or why is accurately defining it important?
Well, in the modern era, it has become quite often repeated that “volume is the primary driver or hypertrophy”. The idea being that, up to a point, doing more volume does increase the hypertrophy response.
But that idea is regularly stated in research/review papers, by well meaning fitness professionals and elsewhere and they all cite the same paper I linked. Every single one of them. The same phrase, the same reference. Every single time.
Now, as I’ll eventually get around to talking about, the statement as written is wrong (if it were qualified slightly it would be closer to correct but nuance is apparently a lost concept). Volume is, at best, the secondary driver on hypertrophy. Sufficient muscular tension is primary. More specifically progressive tension overload is primary. Everything else including volume, frequency, etc. is completely secondary. Another article for another day.
There is also the issue that when arguments break out about this, you get people talking about volume in a very unqualified way. They may use the terms “high” or “low” volume without defining them or simply talk about volume using a singular metric without specifying other important components.
For a different perspective on this check out Chris Beardsley’s piece on when high-volume training isn’t really high-volume.
And that’s why it matters. First to address a currently repeated thought along with allowing a more intelligent conversation to be had about the topic. Hopefully writing this will get me the momentum I need to update my training volume and hypertrophy series. We’ll see about that last one.
In any case, my primary focus here will be the definition of training volume as it pertains to hypertrophy although I’ll still mention other topics or contexts when/if they are relevant.
As I go, I’ll start to mention a problem that sort of “runs through” most of the current definitions of volume which I’ll address near the end.
The Number of Repetitions
In the weight room, a repetition is generally defined as the lifting and lowering of a weight. So if you do a biceps curl and curl the weight to the top and then lower it, that is one repetition.
There are exceptions. In Olympic lifting, the snatch and clean and jerk are essentially never lowered under control (yes, fine repeat jerk reps) and a single repetition refers to only lifting the weight. You could consider a powerlifting style deadlift that is lifted and then essentially dropped similarly. There’s no real lowering phase, at least not in the sense that it is typically thought of.
But within the context of the majority types of weight training and certainly hypertrophy training, a repetition describes lifting and lowering (or I suppose lowering and then lifting for some movements) the weight one time.
Now, in a sense, repetitions can define at least one aspect of training volume. Someone who lifts a weight once and then takes a break has done less volume than someone who does it 5 times. And they have both done less volume than someone who does it 20 times.
At least in some contexts it is not unheard of to talk about training in terms of repetitions Olympic lifters often talk about the number of repetitions done in training, for example. Prilepin’s table is based around not only “optimal” repetitions per set but optimal reps per workout at different intensities.
For hypertrophy/bodybuilding purposes, it’s been far less common to use total repetitions as a metric to gauge training volume. It’s just not been a thing overall.
That said, in one of the earliest meta-analyses, Wernbom examined hypertrophy in terms of the response to specific numbers of repetitions (really muscular contractions). He came to the conclusion that a volume of 40-60/70 repetitions per session generated the maximal response with both lower and higher values generating a lower overall response.
As I discussed in a previous series, while it’s become fashionable to shit on this analysis, it seems to be fairly consistent with the current optimal set volume (discussed next) for hypertrophy is.
That said, simply counting repetitions per se cannot by itself be an accurate method to determine, measure or even describe volume unless you specify a lot of other factors as well. 40 sets of 1 wouldn’t seem to be identical to 2 sets of 20 or 1 set of 40 as an extreme example.
Certainly the studies Wernbom were looking at would not have been at those extremes to begin with. In one part of the paper he states that the studies he looked at used an average of 6 sets and 60 repetitions. So that’s sets of 10, right in the middle ground.
So there’s already a built-in assumption or two about those values.
But factors such as intensity, fiber recruitment, fatigue over the duration of the set and other factors are doing to all be involved when comparing different numbers of continuous repetitions. This can be addressed by looking at repetitions slightly differently but I’ll come back to that in a bit.
Which brings me to the next definition.
The Number of Sets
For anyone truly new to the terminology of the weight room, a set refers to a series of relatively continuous repetitions. If someone lifts and lowers a weight 8 times with relatively minimal rest between each repetition, that is one set of 8 repetitions. If they rest 90 seconds and do it again they have done 2 sets of 8 repetitions. You get the idea.
Related: How Long Should I Rest Between Sets?
And a fairly common way of addressing training volume would be to use the number of sets done. This has its own complexities in the weight room because these things always do.
For example, one way to count training volume would be the total number of sets done in a week. Someone who does 100 sets in a week has done double the volume of someone who has done 50 sets.
Even in a given workout, someone who did 20 sets did twice the volume of someone who did 10 sets.
But what does that number tell us? Not a hell of a lot by itself.
In a per workout sense, what if you did 20 total sets but did 4 sets apiece of 5 different exercises each for a different muscle group. So you did 4 sets for chest, 4 for back, 4 for quads, 4 for hamstrings and 4 for calves or whatever. It’s 20 sets but it’s only 4 sets for any given muscle group.
In contrast, if someone did only 10 sets in their workout but all 10 were for chest, they’d have done 2.5x the chest volume even if their per workout volume was half as much (10 vs. 20 sets).
The same holds for weekly volumes. Someone who did 100 sets per week of chest for some reason isn’t doing the same thing as someone who does 20 sets/week for 5 different muscle groups.
More simply put: total set count per workout or per week or per month isn’t a terribly relevant metric for the most part.
In terms of muscle hypertrophy, we are only concerned with the number of sets done for a given muscle group per workout or per week. The total weekly volume doesn’t play any real role even if one meta-analysis that I can’t currently find the link to combined upper and lower body volumes in exactly that fashion to decide on an optimal weekly set count recommendation. But that’s just dumb and nobody rational counts sets that way.
Pedantic note: fine, someone might argue that total weekly set volume matters in a global sense of overall training load or overtraining and that’s all fine and well. But in the context of what is being argued in the modern era of training over volume per workout or per week, it’s only relevant to the specific exercise or muscle group.
Even here, using sets per se has its own problems. 10 sets of 1 aren’t the same as 10 sets of 20 as you’re now looking at 10 vs. 200 total repetitions. Not only is the difference in the number of muscular contractions enormously different, you’ve got differences in intensity, energy systems, metabolic fatigue, etc.
Of course, it’s rare for people to really try to compare those types of extremes. Even in the various studies on training volume that are part of the “volume wars”, the repetition ranges tend to be in fairly classical hypertrophy zones.
Related: What is the Hypertrophy Zone?
So usually you’re looking at 8-12 reps per set or thereabouts. Some individual studies have compared more extreme variations but only within themselves (and usually by equating volume in some other fashion).
One research group has argued that counting sets per se can be valid to quantify so long as a few factors are met stating:
According to the results of this review, the total number of sets to failure, or near to, seems to be an adequate method to quantify training volume when the repetition range lies between 6 and 20+ if all the other variables are kept constant
Please note the bolded phrase, it’s important and I will come back to it.
I might personally debate the 20+ or that 10 sets of 6 and 10 sets of 20 are necessarily identical but we may have reached a place where even I’m being overly nitpicky. I wouldn’t personally consider 10 sets of 6 and 10 sets of 30 identical in a training sense but whatever….
Big picture, assuming a few things are taken into account, total set count seems a fairly reasonable approach. And of course, within a certain range of assumptions such as intensity, failure, etc. more or less takes repetition count into account to begin with because now the repetition range has been quantified within a narrow enough range to be semi-comparable.
The “newest” approach to assessing training volume is called volume load. This is defined as
Volume Load = Sets * Reps * Weight
With the occasional addendum “under local gravity” which I find utterly hilarious and pedantic given how little gravity is going to vary across the entire surface of the Earth under most conditions. Until we’re doing comparative studies of lifting on Earth and Mars, worrying about local gravity is pointless.
Anyhow, the idea here is fairly simple, you multiply the sets and reps by the weight lifted and that’s your volume load. Some sample calculations:
- 6 sets of 10 repetitions at 100 lbs = 6*10*100 = 4800 lbs
- 3 sets of 20 repetitions at 80 lbs = 3*20*80 = 4800 lbs
- 2 sets of 40 repetitions at 60 lbs = 2*40*40 = 4800 lbs
And I didn’t pick those numbers at random. As you can see, you achieve the identical volume load with different combinations of sets and reps and load.
And at least in one sense, despite the differences in sets and reps and weight, these workouts would be considered identical due to the volume load being the same.
Is Volume Load the Primary Driver of Hypertrophy?
Now in the same way that “volume is the primary driver of hypertrophy” has become popular to repeat, it’s become equally popular to suggest that volume load is also a primary driver on hypertrophy. Or at least that two dissimilar workouts that generate the same volume load will generate identical results.
This is just the “logical” conclusion from the idea that volume is the primary driver. If all that matters is volume, then how you achieve that volume no longer matters.
And in some cases, it may hold true. In a recent paper, unfortunately on untrained individuals, Longo compared 4 protocols that used either a long (3′) or short rest interval (1′) and a volume matched group or non-volume matched group.
So for example, one subject might have done a long rest interval leg extension with one leg and a volume matched (or non) workout for the other. And the long and the short of it is that when volume load was matched between legs, growth was the same. When volume load wasn’t matched it wasn’t. I’d note again that they were beginners and, more or less, it all tends to work out the same.
However, not all studies find this, especially in the realm of the low-load and blood flow restriction (BFR) studies. These protocols utilize light loads, generally 25-30% of maximum either done simply to failure or with blood flow restriction (a tourniquet tied around the arm or leg). Some work has shown that growth is the same at least under some conditions to high-load (75-80% of maximum) training.
But as often as not the volume load in the low load/BFR group is much higher than the high load group.
For example, Morton took trained men who performed 3 sets of 8-12 at 75-90% of max or 20-25 repetitions at 30-50% of maximum to failure for 12 weeks and saw similar increases in muscle fiber size over that time. However, the high-repetition group had a 60% higher volume load (24,000 kg vs. 14,800 kg). So it took triple the repetitions and 60% more load volume to generate the “same” growth. Other research has found the same.
So clearly, the idea that volume load is the driver on hypertrophy is only conditionally true. In comparisons of high load to low load/BFR work, volume load is invariably much higher the low load/BFR groups to get the “same growth”. You do a lot more work for the same results.
My gut says that if you’re comparing workouts in that range of 6-20 reps I mentioned above, it may be about the same. That is, once you’re above a certain tension or intensity threshold, it’s about the same overall. But once you get below that threshold, as in the low-load or BFR work, it’s not.
Isn’t Load Volume Just Tonnage?
Up above, I described volume load as the “newest” approach to tracking or comparing training volume. And I put the word in quotes for a reason: this isn’t even remotely new.
Since about the 1960’s, both in Olympic lifting and outside of it, it was utterly common for coaches to talk in terms of tonnage. At least that was true for the Eastern European countries.
Coaches would have tonnage goals for individual workouts or weeks or years. Books used to indicate how much tonnage any given athlete in any given sport “had” to do to succeed. So you had to lift a billion kilograms per year or whatever to win.
In the modern era, the only system I know of that still uses tonnage is Westside but that’s not shocking since Louie was originally working from ~40 year old Russian manuals.
But tonnage was fundamentally defined as
Tonnage = sets * reps * load
Which is the same as volume load.
And while attractive because it is quantitative, it has enormous problems. And they are basically the same problems inherent to load-volume.
A Quick Reality Check
Even if they aren’t real-world meaningful, it’s often useful to see if a concept holds water by using an extreme reality check. Consider the following two workouts:
- 1 set of 10 reps at 594 lbs = 1*10*594 = 5940 lbs
- 1 set of 594 reps at 10 lbs = 1*594*10 = 5940 lbs
By the load volume or tonnage concept those workouts are identical.
10 reps at 594 lbs or 594 reps with 10 lbs. Both generate 5940 lbs of load volume/tonnage. Hence they are identical.
Does anybody reading this think it’s true? Or could be true? Of course not. The intensities relative to 1 rep max are different (the 10 kg is essentially aerobic work), the energy system pathways are different, the tension on the muscle fibers is different. The fact that the load volume is identical doesn’t mean anything.
Again, an extreme example to illustrate a point. Clearly just looking at tonnage in isolation doesn’t tell you much of anything. And yes that’s probably a bit of a strawman. But since I rarely see these concepts qualified meaningfully by the people throwing them around, maybe not. I’m addressing what I see written, I can’t know what is actually “meant”.
Inherent Problems with Tonnage and Load Volume
Keep in mind that the tonnage concept mainly came out of Eastern European athlete training and a lot of it was being applied to the Olympic lifts per se. These are movement with relatively similar range of motion, at least in the aggregate. They both start with the bar on the floor and end up with it above your head. The distance the barbell is moving is roughly the same even if the clean and jerk does it in two movements and the snatch in one.
In that vein, Olympic lifting training tends to be more standardized than not. There simply isn’t that much variety inherently present in the training. So looking at tonnage when it may only be including a handful of fairly standardized exercise is one thing. The same could conditionally hold true for some systems of powerlifting. Well, Westside to be honest where Louie seems to refer to tonnage in the dynamic effort movements which don’t vary too much.
But what happens when you start looking at total tonnage per workout or per week and including other movements? Think about the tonnage that you could generate with calf raises. The range of motion is tiny, various biomechanical factors let even tiny calved people move the entire weight stack. You can generate staggering tonnages that don’t mean a damn thing. Yes, this is another extreme example but sort of makes the point.
Related: What’s the Best Way to Train Calves?
Or consider the tonnage that might be generated a manual laborer moving bricks or heavy materials for an 8 hour day. It’s probably pretty enormous in the big picture. But none of it is at a peak intensity. None of it is to limits. We even have the issue of how far it’s being moved. But go try loading 50 lb boxes for 8 hours straight and see how much it wrecks you. Then ask yourself if it was really a training stimulus.
The point of this being that generating staggering tonnage or load volume numbers for the sake of it ends up missing the forest for the trees. Under certain constrained conditions, it might have some relevance but in others it will be utterly and totally meaningless.
The whole idea of load volume or tonnage doesn’t really work unless you start to factor in other, err, factors. And clearly in and of itself neither is a good metric. If you need triple the repetition count and a 60% higher load volume to get the “same” growth out of low-load and high-load training, clearly volume load per se isn’t the driver. At least not under all conditions.
Which brings me to the problem that sort of “runs” through all of these volume definitions.
There are a number of ways to define training intensity. One is by percentage of 1 repetition maximum (or multiple rep RM). This has commonly been used in Olympic lifting and powerlifting. This is usually called intensity of load. But clearly it can’t work by itself.
A set of 2 reps at 75% of maximum and a set of 12 reps at 75% of maximum are different stimuli despite being at the same percentage of maximum. Even 6 sets of 2 at 75% wouldn’t be the same as 1 set of 12 despite equating both the repetition and volume load.
Other definitions tend to revolve around intensity of effort. We might define this as the proximity to concentric failure (the inability to complete another repetition in good form) and some researchers have suggested that this be used as an endpoint metric in studies to make them comparable.
More recently issues of Rating of Perceived Exertion (RPE), Repetitions in Reserve (RIR) or Repetitions to Failure (RTF) have been proposed to better quantify the intensity of training. Training to 2 RIR is a higher intensity than training at 3 RIR. They take practice to use but can be somewhat accurate.
We might go further and define intensity in terms of focus or concentration. Certainly that, among with other aspects, have been common to bodybuilding training. This one is important and interesting but hard to quantify so I’ll ignore it.
How Intensity of Load Matters
Again, intensity of load refers to the percentage of maximum being used in the exercise. And this matters when you start talking about all of this. I don’t recall if it was Dreschler in his Weightlifting Encyclopedia or Siff in Supertraining (or both) but the point was made that just looking at volume, was irrelevant unless you included a measure of the relative intensity.
Simply put, saying an Olympic lifter did 20 repetitions in the snatch is meaningless without intensity. Was it at 70%, 80%, 90%, 100%? Either Dreshler or Siff or both proposed setting intensity bands such as 70-80%, 80-90% and 90-100% to delineate intensity.
So the goal might be some number of repetitions at 70-80%, some number at 80-90% and some number at 90%+. From memory the Russians recommended specific percentages of the total lifting to be done in each percentage band. For example the grand majority of annual volume was in the 70-80% range and only 10% was done above 90%.
Similarly, Prilepin’s table is divided by intensity range and for good reason.
Here it is again.
Because what you see is a very inverse relationship between intensity and both max sets per rep, the optimal number of reps per set, the total reps per workout and the optimal reps per workout.
At 70-75%, an athlete might get 10-12 reps to failure. But optimal results would be with sets of 3-6 reps. Each workout has a range of 12-24 (2-4 sets of 6, 4-8 sets of 3 or whatever) total repetitions with 18 per workout being the optimal number.
At 90%, the max reps per set drops to 3 with an optimal range of 1-2 repetitions per set, 4-10 repetitions per workout (4-10 sets of 1, 2-5 sets of 2 or whatever) and an optimal 7 reps per workout.
Keep in mind that this is for Olympic lifting where a primary goal is maintaining a high quality of movement per set. By quality I mean technique and bar speed. OL’ers don’t go to failure outside of Crossfit since technique suffers and it does very little good.
Westside modified the above for Pl’ing, cutting the repetitions in roughly half to account for different in repetition speed. For example, you only did 3 singles above 90% in your maximum effort work.
But absolutely none of the above has jack squat to do with hypertrophy and the table shouldn’t be applied to it.
The above leads to the idea that there is some intensity threshold that must be crossed before volume matters or even should be counted. Put differently, below some threshold, the intensity is too low to stimulate any sort of physiological adaptation.
And, depending on context, there is certainly much truth to this. Basically intensities that are too low, especially for submaximal sets don’t count. Olympic lifters don’t count work at 40% or 50%. Even 55-65% is questionable. Maybe for the power movements. Basically until you get into the 70% range or higher, the volume doesn’t matter or count.
Not the sets, not the reps, not the tonnage or volume load. It’s ignored in any calculations or plans.
And as soon as you add that qualifier, suddenly the tonnage concept stops being so stupid or misunderstood. An Olympic lifter who did endless sets of clean pulls at 40% could generate a staggering tonnage. And not an ounce of it would or should count in any calculations since it won’t do them any good in terms of improving performance. And the same holds for the other measures of volume.
Only sets, reps, tonnage, load volume above some intensity threshold in this case count.
The same holds roughly true for strength. In beginners, 60% of maximum may be more than sufficient to stimulate strength gains while this may go up to 80% in trained individuals. In athletes an average training intensity of 85% may be required. Anything lighter just doesn’t count towards the athlete’s meaningful volume.
Note: the above bit about 85% isn’t entirely true. Systems such as Sheiko and Smolov often include a good bit of work below 85%. But this is usually within a higher frequency model and there is always at least one day above the 85% level. The above says “average” training intensity, not “minimum” training intensity for a reason.
But what about hypertrophy? Because here, even if more volume is often required for low-load or BFR training to generate the same results, it’s clear that hypertrophy can occur even at low relative intensities in the realm of 25-35% of maximum.
What’s the Difference Between Strength and Hypertrophy?
Well one difference is that maximal strength has both muscular, neurological and technical factors. And the latter two aren’t optimally trained by lighter work. An athlete has to practice with heavy weights to develop the neural pathways and technical competency to lift maximally. All of the squats at 30% of maximum won’t prepare them for a rep at 95%.
In contrast, hypertrophy is just about turning on muscular protein synthesis which is mostly to do with how high tension contractions lead to activation of mTOR via Focal Adhesion Kinase within the muscle.
How Intensity of Effort Matters
As I described above, intensity of effort will be defined here in terms of how close a given set is to concentric muscular failure, defined as the inability to perform another proper form repetition no matter how much effort is expended.
Related: What is Training Intensity?
And when this variable is included, it starts to become clear how even lower intensity (of load) training can generate hypertrophy. Because when you start to look at the low-load training literature, what immediately falls out of it is that it only really “works” when the set is taken to muscular failure.
Simply, low-load training without going to failure doesn’t generate the same amount of growth as high load training (to failure or not) or low-load training taken to failure.
BFR gets a little bit weirder in that the nature of blood flow restriction causes growth to occur without going to complete muscular failure. But I’ll save the explanation for that for down below.
The take home is this: when you’re talking about hypertrophy, it seems that there is not as much of a critical intensity threshold as for maximal strength. But strength production has other factors at play that can’t get effectively trained with lighter loads.
A clean and jerk changes completely from 75% to 95% in terms of the timing and bar speeds, so does a squat or deadlift. An athlete has to do the heavier work to get better at it.
For hypertrophy it’s really just a mechanical/biochemical process. And it’s now very clear that that can be achieved in a variety of ways.
Related: What is the Hypertrophy Zone?
In this situation, much lower intensities (of load) can still be effective but ONLY if the intensity of effort is high or near maximal. One or the other, or both has to be present. But if neither are present, any volume done doesn’t matter.
Which before wrapping this up, brings me to the following:
Warm-Up Sets Don’t Count
The above section is really just a long way of saying that warm-up sets don’t count. Or rather that sets that are below some threshold of intensity of load and/or effort aren’t part of the training stimulus.
Related: How Do I Warm Up for Lifting?
So let’s say you’re describing the volume of a workout. Let’s say that someone does 2 warm-up sets and then 4 hard sets (hard = high intensity of load or intensity of effort). The simple fact is that nobody in their right mind would count this as 6 sets. Only the 4 working sets matter in terms of volume.
And I only bring this up because of something I saw on another website while preparing to write this article where it was stated that:
Greg Nuckols of Stronger By Science, is one of the first people I know who mentioned the concept of counting the number of hard sets you perform
Now, what I’m about to say is absolutely not a knock against Greg but rather the person who wrote the above statement. Because really? Just really? Greg is the first person he ever saw state that volume should only include the number of hard sets that you perform? Or the first time this person has seen it (no I won’t link out to the article)? Really?
People were ignoring warm-up sets in defining training volume before I hit puberty and that was in 1985 or so. I’ve never counted anything but work sets in any workout I’ve ever written. Neither has literally anybody else I can ever think of. Literally nobody in the history of lifting.
Ok, fine, I take that back. DeLorme (look it up, kids) recommended 3 sets of 10 and only the last set was really a work set. I suppose you could argue that Starr’s 5 sets of 5 was really only 2-3 work sets after 2 warmups. Whatever. You know what I’m taking about here.
Related: What is the 5X5 System?
I mean, sure, some studies are just a huge series of warm-up sets done with a 10′ break. but that’s just a shitty workout design. But no research study I can ever think of has ever counted the warm-up sets in any calculation ever done. Ever.
Only Work Sets Count
But that’s really the take home message on the whole discussion of volume or even the idea that “volume is the primary driver of hypertrophy”.
Only work sets count. Or hard sets. Or whatever you want to call it. And those will be defined by either being above some threshold intensity of load or intensity of effort or both depending on the context and type of training being done.
For improving maximal strength the threshold for intensity of load is usually held at 80-85% although some will include 75% in that realm. Lighter sets might be useful for technical work or explosive work but won’t do much to improve maximum strength in the big picture.
For intensity of effort, I’d say anything less than 4 reps in reserve/4 reps to failure shouldn’t count. Anything easier than that is a warm-up set. And 4 RIR/RTF is right on the cusp (yes, there is the one study that I can’t find right now). You likely have to do a lot more sets at a 4 RIR/RTF than at 2 RIR to make up for the differences in intensity of effort.
Another way would be to gauge bar speed. And again I’m talking about hypertrophy, not strength or power. Usually during a set the bar will stay pretty constant speed and then start to slow down maybe 3-4 RIR/RTF. At 4RIR it slows a bit, at 3RIR it’s slower, at 2 RIR it’s very slow, at 1 RIR it’s sloooooowwwwwwww and barely completes as you grind it through the sticking point. Then you reach muscular failure.
If the bar doesn’t slow, the set shouldn’t count towards your volume. And it’s absurd to even have to qualify that. And yet here we are in 2020 and I’m having to do just that because almost nobody else will.
Warm-up sets don’t count. Only work sets count. FFS.
Ok, almost done.
Effective Reps as a Measure of Volume
Ok here I’m talking purely about hypertrophy, let’s be clear. The idea of effective (or stimulating) reps is a relatively new concept. Though not really since bodybuilders of old used to talk about how the last few hard reps of a set were the ones that mattered for growth. Even THEY knew not to count f’ing warmups.
But in the modern era, it’s been a little bit more systematized and formalized within the realm of muscular physiology. I’m not sure who came up with it but Chris Beardsley has written rather extensively about it. And I’ve written similarly in various series on my site. Even though I didn’t use the term, my early article on the optimal number of reps per set for hypertrophy was related to it.
Let me make it clear that this is currently a speculative model which needs more direct research. It’s an attempt to synthesize the different research to try to explain why so many different things seem to be “working”. That is, to develop a model/determine the common mechanism of hypertrophy that can include everything from heavy sets of 5-8 to light sets of 25-35 to failure to Blood Flow Restriction (BFR).
The idea here is that the only repetitions that “count” in terms of stimulating hypertrophy are those that are done under conditions of full muscular recruitment. I’ve gone into the weeds on this elsewhere on the site and all you need to know is that you can reach full muscular recruitment in one of two ways:
- Lifting a heavy weight of 80-85% of maximum either to failure or not
- Taking a lighter weight to failure
In the first case, you get effectively full muscle fiber recruitment from the first repetition of the set which continues until the set ends 5-8 reps later. In the second case you get far less than full fiber recruitment initially with increasing fiber recruitment as the set proceeds. As fatigue increases throughout the set, more and more muscle fibers are recruited.
By the end of the set, perhaps the last 3-5 repetitions of a 30-35 repetition low-load set you achieve essentially full recruitment. The weight moves just as slowly as if you had been lifting heavy to begin with and physiologically, the fiber are experiencing essentially the same high tension stimulus that turns on growth. So from the muscles “point of view” the physiological stimulus is essentially identical.
Note: If you’re wondering why I keep saying “essentially” it’s because the topic is a bit more complicated than this but I don’t have space to address it. And also to cut off the nitpickers at the pass who want to get up my ass about how full EMG activation is not always achieved in lighter sets.
In that vein, BFR achieves the same basic effect by increasing fiber recruitment through various mechanisms such as metabolite buildup such that even a submaximal non-failure set will achieve essentially full fiber recruitment near the end. So you end up achieving some number of muscular contractions under full recruitment.
And the take home of this is that a heavy set of 5-8 to failure, a light set of 30-35 to failure and a BFR set close to/to failure generate the essentially same number of “effective reps” in the sense of high tension muscular contractions under conditions of full recruitment.
Let’s assume that each set generates 5 effective reps per set. This would imply that regardless of repetition count or volume load 3 sets of 5-8, 3 sets of 30-35 or 3 sets of BFR all generate 15 effective reps.
That’s why they can all generate the “same” growth: the number of effective reps per set and per workout are the same. Fine, set volume is the same but who cares. In the low-load/BFR training you’re doing nearly triple the repetition volume and 50-60% or more of the load volume. And clearly those aren’t the relevant metrics.
Rather, the relevant metric is the number of repetitions in any given set or workout that actually stimulate growth via the FAK/mTOR pathway.
Related: What Stimulates Muscle to Grow?
The Future of Training Volume Arguments
Now, assuming that the effective rep model is found to be valid, and it might or it might not, going forwards we might not talk in terms of repetitions, sets, volume load or tonnage. Rather, we might describe hypertrophy training in terms of the number of effective reps per set or per workout or per week. And this would likely provide much more coherent discussions.
Because at a fundamental level, the effective reps concept essentially includes the problems that tend to underlie the volume debates. Talking about reps per set is meaningless in and of itself. A set of 15 when you could do 30 to failure and a set of 15 to failure aren’t the same. The first is a warm-up generating zero effective reps while the second is a work/hard set generating 3-5.
Talking about sets per se is equally meaningless. A set of 10 at 4 reps from failure and a set of 10 to failure are not equivalent. The first is damn close to a warm-up and might achieve 1 effective rep while the second is a work set and probably achieves 3-4. In which case it would take 3-4 times as many sets of 10 at 4RIR to “equal” the one hard set.
Which might start to explain some of the apparent discrepancies between studies.
Load volume and tonnage are both meaningless without some either an intensity of load threshold (for performance sports) and/or intensity of effort threshold (for hypertrophy). Even there, it’s clear that neither are particularly relevant metrics for hypertrophy.
Low-load/BFR training may generate 50-60% higher load volumes while requiring up to triple the repeitions than heavy training. But the growth is the same. So who really cares about load volume at least in an acute sense?
The Future of Training Volume Studies
Better yet, rather than doing more asinine studies comparing various numbers of weekly sets under different conditions such as concentric failure, form failure, long rest intervals, short rest intervals and high or low RIR values, the right studies might get done under this model.
Because IF effective reps are what matters, then the question we need to ask is what number of effective reps per workout or per week is optimal to maximize growth? Not the number of total sets or reps or intensity or anything else. IF effective reps are the driver on growth, the correct comparison is effective reps per set/workout/week
With that background, the workouts and studies can then be designed in such a way to compare that relevant metric.
Because at this point we have a data set of volume studies that are pretty disparate. Some use concentric failure with long rest intervals while others use form failure and a short rest interval (meaning that the set will be terminated far from true muscular failure). Which presumably means that two different studies are generating totally different numbers of “effective reps” per set even if the set count is the same.
And trying to compare those studies to one another becomes a fool’s errand. Because you can’t meaningfully compare training volume in terms of sets between studies if those sets aren’t equivalent to begin with.
And I suspect that those differences may explain some of the apparent discrepancies in the volume studies. Because if one study uses a protocol where every set achieves 3-5 effective reps per set and another uses a protocol where every set achieves only 1-2 effective reps per set, that second study may “need” 2-3 times as many sets to achieve the same growth.
But now I’m getting ahead of myself into the update to my training volume series. Next time.