I’ll admit up prime that the purpose I’m going to make on this article will probably come throughout as one thing that’s painfully apparent. However, sadly, I believe it’s obligatory to handle a analysis interpretation error that appears to be more and more frequent. So, what level am I making an attempt to make on this article?
Energy information is much less informative about hypertrophy than hypertrophy information is.
That’s it. That’s the purpose. If you happen to already perceive this very primary idea, you’ll be able to cease studying now. If you happen to needed to re-read the assertion as a result of it appeared so apparent that you just felt such as you have been lacking one thing, I perceive.
However, I felt the necessity to write this text as a result of the concept you can make dependable inferences about hypertrophy from energy information is turning into more and more frequent. Even worse, the concept energy information is even higher than hypertrophy information for making inferences about hypertrophy is turning into more and more frequent.
As is the case with many doubtful approaches to analysis interpretation, the surge in recognition of this (outrageously dumb) thought comes not from the scientific literature itself, however from motivated reasoning and interpersonal battle on social media.
If you happen to comply with “evidence-based health” drama, you’re most likely conscious of a current series of pre-printed meta-regressions by Pelland and colleagues. If not, a) kudos (for lacking the drama, not the paper), and b) I ought to be capable of get you on top of things fairly shortly.
Lengthy story brief, there’s a decades-old feud concerning the impression of coaching quantity on muscle development. Most of the current-day individuals on this feud most likely don’t even notice they’re getting into an argument that’s been raging since (at the least) the Nineteen Sixties. However, every era of lifters, bodybuilders, and energy nerds has had a contingent of individuals arguing that greater coaching volumes (usually) result in extra muscle development, and one other contingent of individuals arguing that muscle development is maximized at comparatively low coaching volumes, and that additional will increase in quantity are “junk quantity” (further work yielding no further outcomes) at finest, and a one-way ticket to burnout, accidents, and overtraining at worst.
Till fairly not too long ago, this argument principally hinged on wishy-washy presumed mechanisms, logical extrapolations, and examples of profitable bodybuilders who achieved nice success with higher-volume and lower-volume approaches to coaching. There merely wasn’t a lot empirical proof on the subject. There have been only a few research investigating the impression of coaching quantity on muscle development, and even fewer that employed what most individuals would think about to be “excessive quantity” coaching.
We lastly began getting some analysis on the impression of coaching quantity on muscle development within the mid-90s.
By 2010, there was a grand whole of 8 research on the impression of coaching quantity on muscle development, however solely 3 of them included teams performing greater than 10 units per muscle group, per week.
By 2017, we had 15 research in whole, however solely two of them included teams doing at the least 20 units per muscle group per week (the purpose at which most individuals would start to characterize coaching as “excessive quantity”).
By 2022, we lastly had sufficient high-volume research (7) to warrant their very own meta-analysis.
Lastly, in 2024, we acquired Pelland’s pre-printed meta-regression with 35 whole research on coaching quantity, containing a complete of 220 particular person results, together with 40 particular person impact estimates noticed when coaching with at the least 20 units per week.
Lengthy story brief: Issues are wanting fairly good for coaching quantity.
Now, I don’t intend for this text to be an in-depth dialogue of the impression of coaching quantity on muscle development, and even an in-depth dialogue of the Pelland meta-regressions. Quite, I simply wished to set the scene for the latest battle within the quantity wars. After three a long time of analysis, we now have a pretty big physique of empirical proof suggesting that greater coaching volumes do are likely to trigger extra muscle development. That put the low-volume camp on the defensive.
While you’re engaged in a scientific dialogue, and the burden of the strongest and most direct empirical proof is overwhelmingly on the facet of your opponents, you may have roughly three choices:
- Admit you have been mistaken. That is clearly no good. It’s unhealthy for the ego, and could also be unhealthy for enterprise if you happen to’ve constructed an viewers by selling concepts that now seem like empirically falsified. (Word: that is usually what it’s best to really do.)
- Retreat again to extra oblique types of proof. That is really no good (at the least in isolation). Attempting to counter a big physique of direct longitudinal proof solely with wishy-washy presumed mechanisms and logical extrapolations is the equal of bringing a knife to a gun struggle.
- Try to impugn the veracity, high quality, and reliability of all of that pesky empirical proof.
If you happen to guessed that many of the low-volume combatants sashayed proper by way of door quantity 3, you’d be right. It is a time-honored technique pioneered by huge tobacco, and carried ahead by all types of scoundrels – local weather change denialists, COVID denialists, and anti-vax cranks, simply to call a number of. Regardless of the energy of the proof arrayed towards you, if you happen to can maintain up one or two research that seem to assist your place, and give you at the least a number of (extra is healthier) reasonable-sounding arguments to make individuals query the entire pesky research you don’t like, you’ll be able to win a depressingly giant variety of individuals over to your mind-set and keep within the struggle.
Once more, I don’t intend for this to be an in-depth dialogue of coaching quantity, or a full blow-by-blow accounting of the kerfuffle attributable to the Pelland meta-regressions. So, we’re not going to dissect the time course of muscle edema, the energy of the repeated bout impact, the impression of relaxation interval length, whether or not individuals are really coaching to failure in these research, or any of the opposite lively fronts within the quantity wars. Quite, I merely wished to explain the milieu from which emerged absolutely the turd of an concept that led to this text.
One of many arguments put forth by the low-volume camp was: In the exact same pre-print that reported additional will increase in muscle development when growing coaching quantity past 20 units per week, it’s very curious that energy features plateaued when coaching with greater than 5 units per week. Since muscle development should be contributing to the energy features that occurred, it’s merely unimaginable that energy features would plateau at such a low coaching quantity, however muscle development would preserve growing at considerably greater coaching volumes. Subsequently, precise muscle development should have plateaued at a lot decrease coaching volumes, and the look of additional will increase in muscle development have to be attributable to … one thing else (progressive will increase in muscle edema, a mirage solely attributable to research with brief relaxation intervals, intimations of fraud or shady meddling from the researchers, and many others.).
In different phrases: We will make extra dependable inferences about hypertrophy from energy information than we are able to from precise hypertrophy information. The energy information seems to battle with the hypertrophy information, and the energy information ought to win out.
I totally meant to simply ignore this concept as a result of, whereas it is a really silly thought, it additionally gave the impression to be an concept that was contained to at least one very silly argument. That’s not a very unusual dynamic. In spite of everything, a great deal of individuals allowed themselves to be fooled by the smokescreens deployed by huge tobacco as a way to obscure the hyperlink between cigarettes and lung most cancers (as a result of they wished to maintain smoking), however they have been completely prepared to just accept very comparable epidemiological proof that was used to determine the dangers related to different merchandise or substances. In a lot the identical means, I assumed that folks have been prepared to just accept a really dumb thought on this one particular area that has engendered a lot fervor within the lifting group, however absolutely they wouldn’t apply the identical very dumb thought to different domains with decrease emotional funding … proper?
Nevertheless, a lot to my chagrin, I used to be catching up on well-liked threads within the Stronger By Science subreddit, and my abdomen dropped. Somebody was putting forth the same argument on a special subject. One meta-regression analyzed the impact of protein intake on hypertrophy, and one other analyzed the impact of protein intake on strength gains; the commenter contends that since protein consumption past 1.5g/kg didn’t additional improve energy features, it’s extremely unlikely that protein intakes past 1.5g/kg have been capable of improve hypertrophy, even though the precise hypertrophy meta-regression reported further hypertrophy at greater protein intakes. Not solely that, nevertheless it was extraordinarily well-received, and presently sits as one of many prime 50 most-upvoted feedback within the historical past of the sub. I then requested round a bit, and folks famous that they’d additionally seen this fashion of argument cropping up increasingly more of late. Sadly, this concept appears to have damaged containment.
So, that’s why I’m writing this text. I didn’t kill this very dumb thought in its cradle, however I can attempt to snuff it out earlier than it metastasizes additional.
Now, turning to the matter at hand: Why is that this such a dumb thought?
First, for most of the themes that take part in most of the research within the printed literature, we must always count on there to be a fairly weak relationship between muscle development and energy features, even with out tweaking coaching variables (like quantity) or introducing differing experimental manipulations (like adjusting protein intakes). As mentioned in a previous Stronger By Science article, a lot of things past muscle dimension contribute to energy, and a lot of things past hypertrophy contribute to energy features. In consequence, the correlation between muscle development (or features in fat-free mass) and energy features tends to be of weak-to-moderate energy: r ≅ 0.2 for untrained lifters, and r ≅ 0.6 for skilled lifters. In different phrases, variation in muscle development solely explains ~5-35% of the variation in energy features in most populations, more often than not, even when everybody completes the identical coaching program. There will be a stronger relationship in specialised populations (powerlifters, for instance), nevertheless it’s sometimes a correlation of at finest average energy, even when everyone seems to be coaching with the similar quantity, depth, frequency, and many others. When you begin manipulating coaching variables, the associations must be even weaker.
Second, it’s fairly apparent that most of the energy features noticed in most research aren’t primarily as a result of muscle development. If you happen to scroll again as much as the figures from the Pelland meta-regression, you’ll be able to see that many of the hypertrophy research noticed will increase in muscle dimension inside a spread of about 0-10%. For energy, many of the research noticed will increase in a spread of about 0-30%. The common relative energy improve was round 3 times bigger than the typical relative improve in muscle dimension. Or, for a more systematic treatment, the standard impact dimension for hypertrophy noticed within the literature is 0.34, and the standard impact dimension for energy features is 0.87. The relative distinction in exponentiated response ratios (that are unaffected by baseline customary deviations) is even bigger: 5.13% for hypertrophy, versus 22.14% for energy.
In different phrases, even if you happen to assumed that muscle development straight, linearly, causally will increase energy in a direct and deterministic 1:1 method (not an incredible assumption, for the file), solely about 1/4th-1/third of the energy features noticed within the analysis (on common) could possibly be attributed to muscle development. Or, acknowledged in the other way, most of the energy features we observe in most research aren’t primarily attributable to muscle development. Topics merely bettering their basic motor abilities with the workout routines used to evaluate energy, topics growing their particular ability of performing 1RMs, and (I think) connective tissue adaptations that permit for extra environment friendly intramuscular pressure switch play a a lot bigger position.
Merely put, even with probably the most optimistic set of assumptions, we shouldn’t count on most variables to have the identical impression (by way of each total magnitude and dose-response relationship) on each muscle development and energy features as a result of muscle development is categorically not chargeable for many of the energy features noticed in most research. It could solely be affordable to imagine that you just ought to see the identical results if you happen to have been to imagine that the impression of a selected variable on muscle development is similar to the impression of that very same variable on each different contributor to energy features (or that the identical variable has completely no impression on each different contributor to energy features).
Third, we now have fairly a number of examples of our bodies of analysis that examine the impression of a selected variable on muscle development, and that additionally examine the impression of that very same variable on energy features. Within the overwhelming majority of circumstances, we don’t observe similar (and even comparable) energy and hypertrophy responses to the identical variable or coaching manipulation.
Essentially the most well-known instance of this divergence between the energy impression and the muscle development impression of a selected intervention might be the analysis on training intensity (high-load versus low-load coaching). Excessive-load (>60% of 1RM) and low-load (≤60% of 1RM) coaching carried out to failure fairly reliably result in comparable muscle development, however high-load coaching additionally reliably results in bigger energy features. However, whereas that is probably the most well-known instance of energy and hypertrophy diversifications diverging in response to the identical coaching manipulation, it’s removed from the one instance.
Throughout the Pelland meta-regressions, we now have one other instance: coaching frequency. Larger coaching frequencies have a a lot bigger impression on energy features than muscle development.
Proximity to failure is one other nice instance. Coaching nearer to failure has a fairly robust constructive impact on muscle development. Nevertheless, proximity to failure has nearly no impact on energy features inside the printed literature.
Of word, most of the similar individuals who argue that energy outcomes inform us extra concerning the impression of coaching quantity on hypertrophy than the hypertrophy outcomes do, are additionally of the opinion that coaching near failure is completely essential for maximizing muscle development. It’s curious that they don’t apply the identical logic when contemplating the analysis on proximity to failure. In spite of everything, coaching nearer to failure causes extra muscle harm and extra edema than coaching farther from failure. If edema and muscle swelling are the precise explanation for the obvious (however false) useful impression of excessive coaching volumes for muscle development, why are they not additionally the precise explanation for the obvious (however false) useful impression of coaching to failure for muscle development? Since proximity to failure doesn’t impression energy features, shouldn’t we additionally conclude that it doesn’t have an effect on muscle development? (To be clear, the final two sentences have been tongue-in-cheek. I do suppose that prime coaching volumes and coaching near failure are each independently useful for muscle development, and that the relationships between hypertrophy and each proximity to failure and quantity are true relationships that aren’t primarily defined by or attributable to muscle swelling and edema.)
Shifting on, periodization analysis gives us with one other nice instance of the divergence between hypertrophy and energy features in response to the identical coaching manipulation. Periodized coaching tends to trigger bigger energy features than non-periodized coaching and moreover, undulating periodization tends to trigger bigger energy features than linear periodization (at the least in skilled topics). Nevertheless, neither periodization (evaluating periodized to nonperiodized coaching) nor periodization fashion (evaluating linear to undulating periodization fashions) considerably impression muscle development.
Lastly, circling again to vitamin, power deficits result in much less muscle development (at finest), and even losses in lean mass as power deficits get bigger. Nevertheless, the same meta-analysis documenting the marked impression of power deficits on muscle development didn’t discover a vital impact of power deficits on energy features.
Once we zoom out a bit, it turns into clear that divergent muscle and energy responses to the identical experimental manipulation are the rule, not the exception. Some issues which have a big impression on muscle development have a a lot smaller impression (or probably even no impression) on energy features (proximity to failure, power deficits, coaching quantity). Equally, some issues which have a big impression on energy have a a lot smaller impression (or probably even no impression) on muscle development (periodization, coaching frequency, coaching depth). Reverse responses are fairly uncommon in longitudinal analysis – I’m struggling to think about long-term experimental manipulations that sometimes improve energy whereas reducing muscle mass, or vice versa. However, it’s extraordinarily frequent for total impact magnitudes and dose-response relationships to vary when analyzing the muscle- versus strength-promoting impact of some coaching (or vitamin) variable or intervention.
Now, if somebody was prepared to stake out the daring and iconoclastic place that energy diversifications are at all times a greater indicator of hypertrophy than direct measures of hypertrophy are, I would respect them for it. I’d disagree with them, to make sure, however that may at the least be novel and internally constant. Nevertheless, as it’s, the argument that energy information gives a greater indication of hypertrophy than hypertrophy information is one thing I solely see deployed when somebody is confronted with a physique of hypertrophy literature that they don’t like. It’s a rejoinder that may look and sound like a sober and affordable argument till you pause to critically think about it for about 5 seconds. Nevertheless, because it does have the looks of an inexpensive argument, it could actually nonetheless be efficient rhetorically, making individuals doubt robust proof in favor of a lot, a lot weaker proof. Now that you just’ve learn this text, try to be outfitted to acknowledge and dismiss it the following time you encounter it within the wild.
Just a few very temporary notes earlier than signing off:
- I’m on no account saying that proponents of low-volume coaching are equal to huge tobacco, COVID denialists, or anti-vax cranks. I’m merely mentioning that (fairly canny) individuals are likely to rummage round in a standard bag of rhetorical tips after they notice the proof is towards them, however they’re unable or unwilling to alter or modify their place.
- I think a variety of the individuals deploying this argument are actually doing so in a little bit of a “monkey see, monkey do” means. In different phrases, I think they’re repeating it with the idea that it’s a powerful argument as a result of they’ve seen it utilized by influencers they comply with, they usually assume these influencers are brighter (or extra intellectually trustworthy) than they are surely.
- The argument mentioned on this article (counting on energy information to make inferences about hypertrophy while you additionally have a sturdy physique of hypertrophy information) is distinct from merely making weak inferences when confronted with a scarcity of higher proof. For instance, if three research counsel that Factor A will increase energy features, however there are not any hypertrophy research on Factor A, it’s not unreasonable to tentatively assume that Factor A might have a constructive impact on hypertrophy as nicely. However, as soon as there are loads of hypertrophy research about Factor A, the hypertrophy outcomes ought to carry much more weight in no matter hypertrophy-related inferences you make.
- For the file, I do really suppose there are nonetheless loads of attention-grabbing inquiries to be requested and discussions available associated to the impression of quantity on muscle development. However I additionally don’t discover most of the arguments put forth by the present crop of low-volume followers (zealots?) to be notably attention-grabbing or compelling.
- I blocked out the names and username within the screenshot of the remark from the SBS subreddit for a purpose. Don’t be bizarre and hassle individuals.
- Maintain the context of this text in thoughts. I’m simply discussing the relationships between hypertrophy and energy adjustments noticed between teams and between research within the printed scientific literature. Certainly not am I saying that energy adjustments aren’t a good indicator of hypertrophy on the stage of the person. In truth, I believe that energy features will be (and sometimes are) a pretty good indicator of hypertrophy in sure contexts. Nevertheless, these contexts considerably differ from the circumstances of most research.
