Can't believe this actually happened.

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the dumb thing about applying the skin in the game logic to a topic like this is just because you want to figure out what works doesn't mean you can (reliably). there are so many variables that go into gaining muscle (or whatever other type of fitness you are into) that parsing out what works absent control is nearly impossible. loads of people *think* they have figured it out but they are just overfitting, something of course humans are quite good at. also because the impact of some variables dwarfs them impact of others (e.g. genetic variability in training response versus how long you rest between sets, or whether you are on PEDs) people are frequently confused about why they (or some other person) is or is not high performing. people that are huge or super fit or whatever are much more likely to be high responders to training (or PEDs) and are consequentially much less likely to understand what will make someone else develop.

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Am I the only one who doesn't see the forum users being all that wrong? They don't quite hit on the right model (what matters is training volume), but "If shorter rests reduce what you are capable of doing, you are probably leaving some gainz in the gym" seems in the right ballpark, right?

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How tightknit and close is the community really? In my 5 year semi-gym rat experience until very recently most weightlifters didn't publish/youtube their methods or publish books, etc. and many weren't posting their tips on boards - it was and still largely is a verbal tradition. The methods of bodybuilders and powerlifters has changed rapidly recently with more social media exposure and was always a group that experimented a lot but you just wouldn't always hear about the experiment or the results - for n=1 when I got into lifting it was taught to me to take longer rests on most sets and most days...

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Painscience.com makes the point that the whole concept of stretching is scientifically unsupported and very dubious.

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I don't think measuring the mass gains is the right metric for bodybuilders. They are going for size which isn't the same thing, powerlifters are denser and stronger but don't win bodybuilding contests

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It seems obviously critical that if you rest 5 minutes between sets you can only do 1/5 of much work in a given amount of time as if you rest 1 minute between sets. Setting the work equal seems like a complete sham.

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scott you're still confused here. two points about metis you're missing:

1. rule zero of bro lifting science has alwas been "stop worrying about RCTs and get your ass to the gym," which contains "if taking short breaks gets you to work out, do that, if taking long breaks gets you to work out, do that". prioritization is contained in metis truth, not in abstract truth.

2. do you think gym bros could do the research deep-dive you did? it's unclear to me whether they could even navigate the landscape of peer reviewed papers to achieve these results. i couldn't and i'm fairly smart. parsing academic lit is its own skill.

The larger point is that metis is good because it captures "attainability/practicality" instead of an abstract, perhaps unattainable form of abstract accuracy. this matter when you want to do things as opposed to simply knowing things.

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If I'm understanding correctly, it seems to me like the science is saying it isn't very important how long you rest. If that's the case, I wouldn't necessarily expect metis to figure that out. Metis isn't built around finding the truth per se - it's built around putting together an internally coherent set of practices that work to produce a desirable result. I wouldn't necessarily expect metis to optimize away all inefficiencies, and in this case having a rule around resting time doesn't even seem inefficient, just unnecessary.

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"On the other hand, some of their failure seems to have come from taking past scientific studies too seriously."

I think you might be running into something that's pretty specific to the bodybuilding community, which is a widespread and intense interest in reading scientific studies, but a lack of sufficient training to read them critically and synthetically, given the detail and the volume. So some of this is people trying to overthink things and doing badly because of it.

(I would note, as someone who listens every week to the clinical updates on microbe.tv/twiv, that — according to their lead clinician — highly trained doctors immersed in evidence-based western medicine apparently continue to recommend COVID treatments that have been shown to be ineffective or counterproductive, because they too have trouble synthesizing and tracking what research has shown to be most effective)

Bodybuilding/powerlifting metis for the strongest, largest people I know doesn't actually take the form of knowing how to get bigger: it takes the form of *how to not get injured.* One of the biggest guys I know at the MIT gym — I think he's a postdoc in physics — usually spends at least 60 minutes stretching before he begins lifting. When I asked him why, he said something like "well, I love lifting weights, and I want to do so for the rest of my life, so I don't want to get injured. Over time, I have learned to be able to pay attention to my body, to notice where I'm tight or stiff, and to focus on that rather than on just lifting heavier stuff all the time."

It's super easy to get bigger through quantitative approaches: lift progressively heavy things, eat more. What you're quoting above is really fine grained optimization at the margins on these things that lend themselves to analysis.

The metis stuff is how not to get injured, I think, which is much harder to quantify and involves more of the intent listening, focus, craft, and mentorship.

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Lifting weights for hypertrophy is in fact a primarily anaerobic activity, though slow twitch relies on oxidation. Glad that was mentioned. When you start adding rest time variables, what youre really doing is simultaneously working your metabolic and cardiovascular efficiency. Might recommend mike mentzer and dorian yates’ “Heavy Duty” and “Blood and Guts” respectively. Among other details they advocated just 1 working set to failure. Anything beyond that seems to be superfluous for bodybuilding.

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I'm going to suggest a good comparison of Metis to the peered reviewed study in two different populations. Priests and Rabbis have been helping people cope with depression, loss, sadness forever. Do they get formal training, what does that training say, is it different than what a therapist would do? Is it better? I mean priest have been doing trauma counseling for 100s of years, are they any good at it, better than our grief counselors or shrinks?

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It seems pretty obvious to me that you probably want both. Intuition, selective pressure, and imitating successful people can only get you so far, and the same is true of measurements, numbers, spreadsheets, and abstractions.

It seems like a lot of people want to fall _really hard_ on one side or the other: either you go all in on your intuition and grandmother's recipes, trusting the tried and true methods - or else you're all numbers and spreadsheet and toe shoes and soy lent.

This seems to be a general, pattern, too, in different modes of cognition: some people are great at saying 'no' to ideas but have a hard time saying yes to anything remotely creative. Others are creative fountains but can't constraint themselves to just pursuing a few ideas that are relatively close to feasible.

It seems that wherever tradeoffs exist, a lot of people want to just rest entirely on one side or the other. Anyone else notice this?

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Enjoyed this article, which bridged two of my interests.

I've a couple of thoughts.

1. The fast feedback and personal experiments of metis are real and their results are tangible and positive. People who train almost always slowly gravitate towards the correct information and make progress. Very few people in their 3rd year of bodybuilding are doing long distance roadwork and bodyweight exercises.

2. However, the road is long, the local optima plentiful and the configuration space is huge. So past a certain point it becomes really hard to find the optimal program.

3. As Scott discovered, broscience is very diverse. Sure there are some common opinions, but there is loads of contradictory and contrarian stuff. I suspect this is the case with all metis. The value of science is cutting down the weeds so more flowers will grow.

4. There's no clear point where the science kills the metis. If you trained based on the science in the 90s you would have constantly plateaued as you gambled everything on studies of untrained unmuscled individuals. Now there are studies that deliver BRUTAL routines to elite level trainees.

5. The process of incorporating the science into the metis is the snake that eats its tail, as the latter will inform your ability to sniff out the quality studies in the former. For this reason Menno Henselmans himself says the process must be BAYESIAN. How's that for full circle.


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I would disagree with the claim that "peer-reviewed academic studies still seems to be the way to go" for fitness; my general impression is that academic studies lag best practices known among informed athletes and coaches. Academic studies often have a lot a limitations especially with advanced athletes over long time periods, because very few study participants are advanced and very few studies are over long time periods. Indeed, I just wrote a comment in the last open thread about how I got screwed in my own training by putting too much stock in a couple academic studies, which had correct conclusions about how beginners can train, but it's incorrect if you're not a beginner.

As for rest periods, there is indeed a lot of unsupported dogma out there, but among well-informed coaches and athletes (meaning, people who have actually tried training with varying rest lengths) I think it's well-understood that: (1) longer rests are overall better, because you can push yourself harder in each set (2) though longer rests are better overall, short rests have benefits for building work capacity and for metabolite training (3) since you don't have infinite gym time, shorter rests often make sense even in situations where long rest would be better for your goal. For bodybuilders who are doing like 100 different exercises (I exaggerate) to be sure every muscle gets a full workout, they can't wait 5 minutes between every set and realistically complete their workouts. For strength athletes specializing in just a few lifts, they rest as much as they want for maximum performance in every set.

If you want really good information about strength training or bodybuilding, the best source is coaches who are smart, open-minded, and knowledgeable in both academic literature as well as the training methods of top athletes. One source I can recommend is the guys at Renaissance Periodization (https://www.youtube.com/channel/UCfQgsKhHjSyRLOp9mnffqVg); they have videos specifically about rest periods if you want to see their thoughts.

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"There is no pure untouched community of noble savage bodybuilders, forming an academic-science-free control group"

In a way, this shouldn't matter. If the people with skin in the game decide that the best info is coming from academia, then shouldn't Taleb/Scott accept that as being the right decision?

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Metis is one factor, thymos is another; a lot of bodybuilding/fitness lore is about optimizing *long-term motivation*, not maximizing pounds of muscle added per gym-hour. So I'd expect bodybuilding wisdom to skew to things that work reasonably well and feel good.

While they do get long-term feedback from changes in appearance, the short-term visible feedback comes from a) how you feel during/after the workout, and b) progression in how much you lift. (e.g. a typical bulking cycle might mean adding half a pound of muscle and half a pound of fat each week. After a month, you'll be bigger, but also fatter; it's really hard to eyeball changes. You could test different lifting strategies over time, but for many of them the payoff cycle is: rapid gains from getting technically better at doing the lifts -> gains from actually getting stronger -> slower gains as you reach limits). And the longer the periods between changes, the more *other* factors change. The solo RCT is hard.

Another thing that makes practitioners reluctant to change their behaviors in lifting is that a big part of the motivation is seeing a number go up. But that's only meaningful if you are doing exactly the same workout each time; if your lifts go up, but you increased your rest times, you didn't necessarily get stronger, and it's demotivating to worry that your measurement only looks better because of how you measured it.

This is a kind of annoying answer, but I think it gets to the fundamental truth: what fitness researchers are trying to measure is the effect of controlled experiments. What bodybuilders are trying to do is to get big. And getting big is not a series of controlled experiments; it's partly an effort to impose some level of control on the random fluctuations in life (injuries, schedule changes, etc.) that interfere with maximum gainz. You can look at bodybuilding wisdom as a sort of bro canon, not in the sense of embodying what bros think, but embodying how a true bro would motivate you to keep going for one more set.

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Doesn’t seem like you established that this is consensus in the community by any means, and most of what you shared was contrary to that point. Your conclusion seems pretty shoehorned... because some people of a generalized body are wrong means there is a failure of ‘metis’? This is nothing more than a debunking of what most in the fitness/bodybuilding community would consider an old wives tale....

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America’s Test Kitchen applied the scientific method to a lot of culinary folk wisdom and it was found wanting.

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While this is a completely new topic for me, I would've expected the bodybuilders to have a generally decent grasp of what makes one "good", without a strong grasp of what it takes to cross the last decile, or last percentile, of gains. They, by almost any measure, haven't "failed miserably" re their end goal from what I can see.

Metis seems to stand in for a shorthand for "generally accepted practices within a community, that evolved to reach strong end goals". But it's evolved, which means it won't be optimised for everything, and might even have counterproductive aspects. The same way that "scientific endeavours" you're citing are engineered, and also will have blind spots that will need correction eventually.

If I have to propose a model I'd think it'll be more like "Given sufficient time and people, metis will get you pretty close to where you wanna go. But you might want to test scientifically to make sure your ideas stack up, as there's a very high probability that a bunch of them might be counterproductive, just not so counterproductive that you'll make no progress."

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Several months ago I tried to answer for myself whether resistance bands are "about as effective" as free weights for strength training. The most comprehensive attempt to answer the question I could find was here: https://bonytobeastly.com/resistance-bands-for-muscle-hypertrophy/. (There are some possibly-relevant studies, which the author of that piece selectively references, but none that I found attempted to directly measure hypertrophy or strength gains over time in a controlled trial that compares resistance band training and free weight training.)

If the author of that piece is to be believed, it's the expert consensus that resistance bands are definitely strictly inferior to free weights for building muscle, specifically and solely because 1. a small number of recent studies indicate that tension at long muscle lengths promotes hypertrophy more than tension at short muscle lengths and 2. resistance bands must theoretically have a "resistance curve" that's the opposite of that, i.e. more tension is applied at the end of the range of motion where the working muscles are contracted.

I found this pretty striking since it seems like the author, and apparently all the experts too, are putting *too much* faith into too light a body of relevant evidence and *underweighting* the relevance of "metis"-oriented arguments along the lines of "well it certainly looks and feels exactly like effective strength training in every way, and many people who claim to be experienced lifters think it's effective for them, so why wouldn't it be about as effective". Personally, I'm still training with my resistance bands and am happy with the rate of progress I've seen thus far.

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This is a scientific shitpost if I've ever seen one.

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You might be interested in the recent exchange between Menno Henselmans and the people at strongerbyscience.com on the subject of whether having high body fat impedes hypertrophy. It greatly lowered my faith in Menno's ability to draw good conclusions from a body of evidence, tbh (though of course that doesn't mean he's actually wrong about any other specific claim he's ever made). https://www.strongerbyscience.com/p-ratios-rebuttal-2/

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> But here’s what seems like an example of body-builders failing miserably, and needing normal academic science to set them right

There's also the very strong possibility that the difference between N or M rest minutes is irrelevant as a muscle growth factor compared to their use of stereoids and similar enhancers, so it makes sense for lesser "natural" methods not to be as optimized.

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Kinda reminds me of Moneyball. Lots of skin in the game on the part of scouts, teams, coaches, GM's, and players, yet they were wrong about important facets of the sport for decades.

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It seems wrong to argue about whether or not bodybuilders got it right/wrong in the past (or indeed now) purely by referencing the changing scientific consensus, since that's fundamentally part of the question. What methods do the top bodybuilders use now as compared to 30 years ago, and how big are they, etc.? You need to measure it by bodybuilder end-point metrics, not immediate metabolic measures which are innately far more vulnerable to confusion.

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The bigger issue is science is once again useless at giving any sort of practical result. For years the science was uncertain about low-carb diets. Meanwhile everyone I've ever met who has successfully lost weight has done so on a low carb diet. Science just isn't very useful outside of carefully controlled environments. Which is to say science isn't all that useful. Science and technology get all the credit for progress, but it's capitalism that deserves it. Soviets had lots of great scientists.

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>I found this interesting because some people hold up (no pun intended) bodybuilders as an almost-perfectly-incentivized “scientific” community. Every bodybuilder has his own skin in the game - based on getting the science right or wrong, he’ll be better or worse at what he does. There’s a quick feedback loop - you can see if you’re gaining muscle or not. And success is easy to observe - check if the person giving you advice has arms that look like tree trunks.




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> But here’s what seems like an example of body-builders failing miserably, and needing normal academic science to set them right.

/Something/ feels off about the logic "which is more accurate, metis or scientific studies? we checked, and scientific studies say scientific studies are more accurate. so much for metis!"

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There was a discussion on r/slatestarcodex a few weeks back about this interview with former bodybuilder Sam Fussell: https://www.drmichaeljoyner.com/sam-fussell-an-interview-with-the-author-of-muscle/

An important takeaway from this is that illegal* steroid use is (or was, but Fussell doesn't indicate that it has changed) endemic among the bodybuilder community. As a result, their metis is completely different from the mainstream scientific community, which is presumably not "in the know". But I'm not an expert on this so it's possible that on the question of how long to rest between sets is unaffected by how much drugs you're on.

(Reddit thread: https://old.reddit.com/r/slatestarcodex/comments/mdf04d/fussell_on_muscle/)

*Illegal in the sense that it gets you banned from sports, not that steroids are illegal drugs, which AFAIK they aren't.

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Almost all of those studies seemed to measure contrasting conditions that both fall under "short rest periods of 1-3 minutes", especially if you consider that as an unscientific estimate that might be as little as 30 seconds and as long as 5 minutes.

I was left entirely uncertain about what was being asserted or proved.

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The problem the bros have is their N=1, or at least some small number depending on how many gym buddies they have. And it can be hard for them to get themselves to consistently change their training methods, especially if they think the new one isn't working. The scientists have a much larger N and more controlled conditions, but their results might not generalize.

I think if you really want to know what works, you have competitions, and you have your academics working as and advising trainers. If the trainers who follow the Long Rest school have athletes who keep beating the athletes of the Short Rest school at competitions... well, there's your answer. Assuming there aren't confounders like the Long Rest athletes coming from Samoa and the Short Rest ones coming from New Jersey or something. I believe this sort of thing has resulted in big gains in swimming and track.

There seems to be a similar thing in bicycle training. Everyone says do intervals, but the major school says a lot of the intervals should be just below your "Functional Threshold Power" (FTP), in the "sweet spot", whereas there's another group which says you should do "polarized" training, always considerably below FTP or considerably above it, and the "sweet spot" is just wasting your time or worse. Unfortunately I have not been able to determine if there are good studies pointing to one or the other.

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The metis is that gym bro’s understand where to focus. Mainly, there’s a lot of emphasis on lifting a lot (volume), diet (eating a lot or eating clean), and the juice. Most of the chatter in bodybuilding is about lifting, diet and juice because most of the results come from lifting a lot, dieting, and juicing. I’m sure the bro’s get a lot of these fringe questions about rest between sets wrong because those effect sizes are de minimis compared to stuff like how to get as much volume in per week without overtraining.

If you want to compare the scientific community to the bro’s core competency, I would focus on the juice. The juice is inherently an area where experts should have an advantage because it’s experts who created these substances and ostensibly oversee their use.

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There is two sides to that dynamic though.

There were things that "bros" were saying for years that have only recently been shown to be more plausible than previously thought. The only example I have of the top of my head is sarcoplasmic hypertrophy (https://www.strongerbyscience.com/sarcoplasmic-vs-myofibrillar-hypertrophy/) but I definitely heard of some others.

... actually, I googled, and here is T-Nation article (unlike the previous link, I'm not vouching for it) that tallies wins and losses for "bro science practices": https://www.t-nation.com/training/4-things-bro-science-got-right

Exercise science has a lot of issues, though a lot of that is the usual stuff, but in particular:

- Most studies don't necessarily look at trained people. Something that is plain as day is that things are very different between a weight lifting newbie and someone that has been at it for years.

- Most studies look at acute interventions (a few workouts followed by measures), not chronic changes in training regimen tracked over the span of months.

- Averages. Some stuff works really well for some people but not for others. The issues here might be cofounders (or "co-factors" maybe). It's really hard to control for everything that matters. As an endeavour, bodybuilding is actually pretty hard, once you've gotten to a certain level. Screw any crucial factor up (sleep, stress levels, nutrition, total training volume, ...) and suddenly your intervention does nothing or even proves detrimental.

I think other fields have similar issues, but the situation here is quite fragile. If you shoot up drugs in someone that's a bit too stressed or doesn't eat enough proteins, it's my understanding that the drugs don't usually stop working or even make your condition worse. Ditto if you increase the amount of drugs. With bodybuilding all of this can, and does, happen.

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Just don't ask how many days in a week there are.

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Would be interesting to do something similar with all the training methods that have appeared since the use of power meters and/or interactive trainers became mainstream among "serious" cyclists.

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That's a gigachad post if ever there was one.

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This is a bit weird to read.

As someone that's mildly close to the sport and exercise field, theres some good stuff in the comments here... And also some stuff that's a little painful to read.

I'm slightly shifting myself to be even *more* cautious about speculating into fields I'm not a part of.

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"But in most of the communities I look into, trusting the peer-reviewed academic studies still seems to be the way to go."

Both muscle gain and medicine are areas where researchers are relatively incentivized to produce correct conclusions right? Not sure that is true in every scientific field. For example, lore has it that in social psychology, interestingness is (was?) incentivized over correctness.

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> None of this should come as a surprise; it’s the same thing that happened to doctors fifty years ago. We thought we’d developed useful lore. Evidence-based medicine showed half of it was wrong.

Given this history, I'm having a hard time understanding why your conclusion is

> But in most of the communities I look into, trusting the peer-reviewed academic studies still seems to be the way to go.

Surely trustomg metis/lore as a way of developing a practice, and allowing that evolved practice to be stripped of ephemera by scientific investigation is the way to go? Are you confident that someone could become an empirically better bodybuilder by reading all the studies first, then going to the gym?

Granted, there are probably domains where the theory is more important than the practice, but if your goal is some (non-academic-paper-publishing) concrete effect, it seems like the better approach by far is building a working, if clunky, set of practical skills and knowledge, then dropping the useless stuff off as you progress.

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There are two communities of bodybuilders.

One community consists of the "pros", which are the ones that enter bodybuilding contests. These are looking to build big muscles with symmetry (and a number of other criteria from the judges). Note that these people do not win based on strength or actual muscle size, but how the muscles look (somewhat like figure skating).

The other community is the "bros". These don't enter contests, but they do compete with each other occasionally, so there is some strength involved, e.g. "What do you bench?". They do have aesthetics in mind - how they look in the tight shirt at the bar.

The people designing these studies generally don't belong to either community. They may ask some people about reasonable sample sizes, program lengths, etc. but they are constrained in cost as to how realistic the programs can be. For example, if you're looking for optimal contest prep programs, note that most contestants seem to take about 12 weeks to prep - from "I'm going to compete" to the actual meet. Most of the studies I've seen don't even last half that long.

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A meta point:

I find it fascinating how I've read all of Scott's writing on metis in addition to likely all of the same source material, yet seemingly understand the concept quite differently.

I think of metis as being valuable in 2 types of situations:

1) it has been used and evolved over long periods of time (if it didn't work, it would have likely died out)

2) it pertains to a realm that is much harder to quantify/analyze

Given the above, I would not expect metis to be more informative than the scientific literature in a relatively new field like body building that is relatively legible to study.

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You only have half of the equation. You have studies showing the effects, or lack thereof, of shorter rest-times. But, you don't have an actual survey of current body builders to find what they believe, or at least claim to believe. You have lots of suggestive evidence of what they believe, but its all evidence that is subject to self-selection bias. Who knows if the guys who write body building articles and answer questions on forums hold the same views as the guys who don't?

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"It said that people training for strength should wait 3-5 minutes, but people training for hypertrophy (bigger muscles) should wait 30 - 60 seconds."

If this is true, it might be part of the difference. I suspect that the scientists are measuring strength, rather than muscle size.

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I think in quite an autistic fashion this post misses forest behind the trees.

In long run it is not really important how long you rest. You will figure out what works for you best.

What matters is diet, exercises , mindset and.. cough.. pharma. Whether you rest 60 or 3 minutes matters jack sh1t

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Never thought I’d see an ACX/powerlifting crossover episode, but here we are!

In my ~year of being in the latter community, I can confirm that metis is spotty at best and misinformation runs rampant. I liken this to Gwern’s review of that old book on animal husbandry (https://www.gwern.net/Bakewell ) — for a long time, people in different fragmented groups were trying to optimize for some set of results they thought they wanted, but doing so in a way that was beholden to various unhelpful priors/biases/delusions. On average, they *kind of* got to good results sometimes, but mostly it was a shit-show until more rigorous modern scientific practices came along. And that’s still where we’re at today in any area (like personal fitness) where anyone can become an “expert” with enough clients or clicks. I’m guessing metis has always been like for anything that’s not strictly life or death, but a long-haul optimization problem.

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If it is work equated, how do you know if the effect is from rest periods, vs. #reps?

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Maybe since these bodybuilding discussions are happening in an online forum where you can't really see the results or gains of the people recommending them they must instead back up what they are saying with scientific studies to seem credible. This then allows bad science to invade maybe

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The language learning community is another with a lot of skin in the game.

Working proficiency is such a long process, small optimizations can save significant amounts of time. It's a little surprising how slowly (if at all) university language settings have embraced tools like the input hypothesis or spaced repetition software, that are widespread in the self-driven learning communities.

On the other hand... there are still a lot of open questions and debates within language learning communities.

Maybe some questions about optimization stick around because a lot of the remaining questions are working so far at the margins? Language learning is a time-on-target activity. If you're spending x hours per day working with the language, that's most of the job.

So, flipping back to the case here, I think if you asked anyone in the lifting community to assign priority weighting to "any program of progressive overload on core lifts" vs. "duration of rest periods" as a point of initial focus... I don't think there would be debates.

If you know the basics, and you know all this other stuff is on the margins, maybe their "metis" is optimizing, but also preventing over-optimization?

i.e., In the world where rest timing led to 20% improvements or something... I think the community would have digested that knowledge. At least somewhat in proportion to relevance.

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in the real world, wouldn't you also be lifting heavier weights at longer rest intervals?

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The first thing you might realize is that no one in these studies is likely to be an actual elite-level bodybuilder. It's entirely possible that figuring out the optimal number of leg extensions for college students isn't optimal for Sergio Olivia Jr on 2g of test/wk eating 7k calories per day with 15 years of training experience under his belt.

The second thing you might realize is that bodybuilding, and indeed sports training in general, defies explicit quantitative analysis. No bodybuilder is setting a stopwatch. They are training by feel. They are also somewhat eating and resting by feel. Athletes are successful because they can autoregulate and ignore the kind of explicit instructions that scientists are looking for in papers, or genpop is looking for in "top 10 exercise habits" lists in mens health magazines.

Bodybuilders will say they "eat clean" chicken and broccoli in interviews and then 4 nights a week are eating McDonalds. No one told them to do that. They may have even been told not to do that. But they just switch their brain off and it all seems to make perfect sense for them. Yes, even during contest prep. Some of the guys who come in the most shredded routinely go off their coach's diet plan egregiously and just laugh about it or rationalize it away or they never even think they cheated at all.

If you wanted to know which explicit simple instructions (like, do 5x5, or rest 90s between sets) causes the most muscle growth in the population you study, keep doing those studies. If you want to know how to become an elite athlete, start by documenting the actual behaviour of elite athletes and highlight the common trends. Spoiler - the basic ingredients are to train hard, eat a lot of food, and use steroids you like.

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>The bodybuilders had lots of opportunities to experiment and tinker, with lots of skin in the game, but they were still getting things pretty wrong until researchers looked into some of their conclusions using the normal scientific method.

I have lifted weights for about 10+ years and made every mistake possible short of ruining my health and injuring myself.

Some comments:

- <em>Bodybuilders are one of the collectively stupidest groups of people I've ever seen</em>. I can't begin to tell you the dumb shit I've seen on bodybuilding.com. <a href="https://www.businessinsider.com/bodybuilders-dont-know-how-many-days-in-week-2015-1">This debate</a> about whether a week has 7 or 8 days has to be up there.

- The "pump" is just increased blood flow. It's irrelevant to building muscle. You can get a great pump by curling a 1 pound weight fifty times.

- Pro bodybuilders are all running stacks of steroids + HGH + insulin. The exact response curves of hormones in response to weightlifting are largely irrelevant to them, as they're dumping massive amounts of artificial hormones into their systems anyway.

- Different weightlifters have different goals. The correct path for an aspirant pro bodybuilder is different to that of a person rehabbing an injury, or a person who wants to lose weight. There's no one-size-fits-all approach.

- Natural muscle gain is very slow (aside from the "newbie gains" when you start lifting). It can be difficult to assess whether your training is working or not when you're only gaining 1-5lb of muscle a year.

- Faced with an infinity of contradictory lifting advice, most bodybuilders adopt a "keep it simple, stupid", approach. As one person told me "more food on your plate + more weight on the bar = more muscle. Don't make it any harder than that!"

- When lifting weights, overwhelmingly the most important consideration is not getting injured. It doesn't matter if your training methods are effective in building muscle if they're also wrecking your joints: soon you won't be able to train at all.

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Isn't the more important gap/difference between metis and Science in fields/practices where the science doesn't have enough specific recommendation?

"Once science is better you should follow it" is not much of a bromide.

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Who would win in what fight?

The having scientifically valid causal descriptions fight, or the getting swole fight?

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I apologize if this is uncharitable/wrong, but as far as I can tell, the only real fundamental pro-science claim here is that knowledge of past RCTs (and similar things) makes you better at predicting the results of similar future RCTs as compared to things metis people say, when the things the metis people say is interpreted as a prediction about future RCTs.

Which isn't a point _against_ the ppl who are into doing RCTs and similar things, but seems kind of weak.

[also, to be fair, a lot of things that people say in bodybuilding are pretty easy to parse as predictions about future RCTs...]

The real issue at hand is the relationship between RCTs and practically useful knowledge/truth.

It seems to me that like in cases where you can reasonably name & isolate a Fact from the mess of real-life bodybuilding practice and culture, then definitely doing RCTs around that Fact will allow you to gain knowledge in a controlled setting (you will certainly accept or reject some hypotheses), and then maybe when you map that knowledge back into the wild, it'll improve practice in meaningful ways.

Certainly you should be able to predict future RCTs around the Fact better.

But like how relatively important are such situations? As compared to more "a-scientific" things (where for a beginner, an "a-scientific" thing might be just like personal stories from other people that make it easier to imagine yourself lifting and then you go do it, I don't know)?

Genuinely not that clear to me.

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I don't think this is a valid evaluation of metis vs legible expertise. The question being answered in these studies (how to get the biggest muscles possible) has only really been a focus of high-level bodybuilding since the reign of Dorian Yates in the early 90s. If you look at major bodybuilders from before then, like Frank Zane and Arnold, they're much less about massive muscles and more about aesthetics.

That gives this kind of bodybuilding <30 years to figure itself out - not anywhere near enough time to establish metis. The examples in SLaS are from cultures that figured things out over thousands of years: I expect the Inuit hadn't nailed down their seal hunting techniques three decades after first entering the arctic.

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Writing about the optimal way to get swole is only going to further persuade the likes of the NYT that this is an alt-right blog.

The real story of course is that the rationalist community is about searching for truth, and there are certain truths that only alt-rightists are willing to proclaim. More and more such examples are coming from the realms of fitness, nutrition, and intersexual dynamics. That's probably a good thing, as alt-right will become just another flavor of right, just like alt-rock became another flavor of rock. As someone who sympathizes with the alt-right, I'd be very happy if it became less about ridiculous political conspiracy theories and more about telling fifteen-year-old boys to lift heavy shit and put it back down again because that's how they'll feel good, get self-confidence, and get laid.

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Your basic premise, that bodybuilders were wrong because they disagreed with exercise research, isn't justified, because exercise research doesn't use bodybuilders as subjects.

There are a small number of bodybuilders in the world, and they're genetic freaks who work out constantly, make bodybuilding their lifestyle, take lots of drugs, and already have a lot of muscle. "Bro science" is designed for, and based on the advice of, the most-elite bodybuilders, and what they have to do to keep gaining muscle is very different from what you, I, or even a typical elite athlete, would have to do.

For example, bro wisdom says to do 3-5 sets of each exercise. Lots of studies show conclusively that, for exercise research subjects, the third set and onward is a waste of time, and the second set might not be worth doing either.

(I'm lying a bit; most of these studies conclude that you should do 3 sets. But the data clearly show that the gain per minute, or gain per work done, is maximal when you do 1 set, and the correct conclusion is that you should do 1-2 sets of many different exercises for many different muscles, rather than 3 sets of fewer exercises. The studies "disagree" because they aren't asking how to exercise most efficiently, but how to exercise one particular muscle so as to gain the most total mass /per exercise session/ (not per minute) for that particular muscle, regardless of how long you have to exercise.)

Bro wisdom says to take 1-3 minutes between sets because pro bodybuilders have to exercise REALLY FAST. Their workout routines are often 30 sets per day. If you take 5 minutes between each set, that's going to take hours per day just waiting between sets!

You and I don't need to do 30 sets per day, because our bodies aren't constantly, aggressively tearing down muscle at the rate that the bodies of pro bodybuilders are. The more muscular you get, the more your body wants to get rid of that expensive muscle.

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It's easy to think of the scientific community as an architecture for producing knowledge. But how that knowledge is distributed and how it derives it's authority are of equal importance.

The gym bros never had an architecture for distribution or verification. Of course they would get stuck on something suboptimal if they are giving each other advice.

Say the mechanism for checking credibility of the advice is the size of someone's arms. Now say we have 1 guy doing something unorthodox and 100 doing the accepted wisdom.

Even if the unorthodox method was better, produced nice big arms, it's still just 1 guy vs those 100 out of whom much more than 1 pair of nice arms would emerge just by sheet statistical likelyness.

I think that if the architecture is not set up for systematically reward 'correct' information, quantity is going to rule.

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By Googling, you only learn the opinions of gym bros that go online and do research. This is undoubtedly a growing percentage, but 10 years ago (when I used to go to a gym that was popular with bodybuilders) it was close to zero. People took advice from the "local experts", who were generally muscular due to genetics and/or drugs, often probably despite their training routines. If someone with ripped arms told a newbie to perform sets of 100 curls on a full moon, most would do it unquestioningly.

My two pence worth on the rest debate is to say that you're probably best actually just doing 1 single set of each exercise anyway, so it's a moot point.

The difference in gains between single vs multiple sets in studies is always pretty tiny, if there is one at all. Couple this with the fact that most people will hit their genetic ceiling pretty quickly, by doing multiple sets with long rest periods you're increasing your time in the gym by x5 to ultimately get the same results after a few years.

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Interesting parallel to sabermetrics etc. in pro sports. The old-style coaches had plenty of experience and plenty of skin in the game, but it turned out that they were making some pretty basic mistakes and the ones who adopted metrics thrived.

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All the studies that explicitly equated work still found no difference. If you can do 4 sets of a slightly lower weight with 1 minute breaks, or 3 sets of a slightly higher weight with 5 minute breaks, you're saving lots of time with the former. Outside of a controlled experiment, saving time leads to getting more work done or being more consistent with your training. The studies so far haven't really addressed the real world consequences of rest time advice. They're like feeding lab rats precise numbers of calories of coca-cola and salad and concluding that for weight loss it doesn't matter whether you eat salad or drink coca-cola. But in the real world ceteris isn't paribus because everything is ad libitum. If somebody can get the same work done in less time, he is likely to end up getting more work done. If you want to test it properly, randomize and tell group A to rest short, tell group B to rest long, and don't control anything else about their training. Even after hearing of all those studies I'd still wager 3:1 odds that the short rest group does not worse than the long rest group.

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All of the comments seem to correctly focus on the false premise of the post: that it's quick/easy to see what's working when you bodybuild.

The meta-question is why Scott didn't bother to talk to someone in the community, any one of which could have clued him in. The "mentis" I'm familiar with would have included:

1) feedback is slow and there are tons of confounding variables

2) age, training age, and genotype all overwhelm any tinkering at the margins

2a) newbie gains aren't real life for long and should probably be treated separately

3) most "bodybuilding" is all about the margins! After 5 years of on-point habits, you're squeaking out a pound or two per year; without juicing, there are no more leaps to be made

4) there's no short-term economic incentive for funding the large long-term studies required to get robust results. (Maybe the military is the only org equipped to control diet and exercise for a large n; they'll even have some twins!) It's a bit mysterious why they don't, since generally poor recruit health has officially been identified as a strategic risk...

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Menno Hanselmans is pretty hard to put into a box. He's practicing bodybuilder, ex data analyst and his last brand name was "bayesianbodybuilding". So quite a lot of empirical knowledge is involved. If anything, he's possibly the best practitioner of the bayesian method I've seen: scarcely anything in fitness science is proven to the proper scientific method standards, so a vast majority of the time you have to work with weak or moderate evidence, plus a large variability in your clients. Knowing how to swim in this sea of evidence is pretty important. It's not the first time he's using a study to argue the opposite of that study's conclusion. Here's his advice on how to read a paper: https://www.facebook.com/MennoHenselmans/posts/research-tip-when-you-want-to-critically-evaluate-a-study-dont-read-the-full-pap/2152206684837155/

Also he's not alone. He's part of a new generation of evidence based PHD bodybuilders that mostly go in the same direction: Brad Schoenfeld (that he mentioned), Mike Israetel, Eric Helms, Greg Nuckols.

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Maybe the bodybuilders fell prey to a common problem of Metis based practices. The harmless ritual. If rest duration has minimal impact, then prescribing a pointless ideal rest duration doesn't hurt gains. Once one is prescribed, it will be very difficult to get rid of.

Hunters may perform some ritual to thank the spirit of their game and put it to rest. This doesn't gain them anything, but because it costs so little it is difficult to get rid of.

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It's worthwhile to consider the biases of all groups with "metis" and in which direction they may err. You mention "primitive tribes" that have an "almost supernatural" knowledge of food preparation - they have a bias in favor of avoiding potential danger and consuming a limited number of knowably safe foods. For these reasons, many such people have "taboos" against foods that are widely considered safe and healthy - e.g. Navajo have a taboo against fish, I recall once seeing a documentary about a New Guinean tribe that has a taboo on citrus, and, perhaps most famously, the ancient Hebrews (and their modern dietary descendants) had a slew of food taboos on everything from pork to shrimp to mixing meat and dairy.

In which direction might Bodybuilder "metis" err? I think it's quite obvious: in the direction of looking tough in front of your other gymbros. The community as a whole might generally try to embrace science and experimentation, but when there's a question with mixed evidence (as was the case of rest periods), they're going to err on the side of what makes them look harder, faster, stronger in the gym, in this case resting less. To suddenly start resting 2-5 minutes between sets might bring marginal long-term gains in muscle growth, but it comes at the short-term cost of looking tired in front of one's peers. The net incentive structure is to pump those sets out as quickly as possible.

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My experience [doing interviews](https://docs.google.com/document/d/1uJTtwNscwroARRMaOUPFzFpRcHDVI-bjVvDVZ7gZtbA/edit) to aid forecasting in 2020 is that there's often less "metis"/on-the-ground-wisdom than I initially expected, at least in a way that's distillable to abstract truths. I was initially uncertain how much this generalizes to beyond things like covid but upon reflection think it generalizes fairly well.

The issue isn't in the world but my map of the world: I often assumed "magic" in the on-the-ground wisdom without considering carefully that any causal model to generate such on-the-ground crowd wisdom would be implausible upon a first glance.

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Isn't the whole point of metis not to optimize blindly for one metric and not to ignore entire reality around it?

If you rest for five minutes instead of two, your workout will take way longer. In reality, just how often will you go to the gym if it takes you double the amount of time? The pump and lifting is enjoyable, waiting is just plain boring. Will you ever enjoy working out if you keep staring at the clock, measure five minutes every time, get bored between each set, then go home after two hours?

Even knowing what the studies say, I would err on the side of more enjoyable shorter workouts, because I know the breaks make negligible difference while consistent gym habit makes all the difference.

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You're asking:

"Who'd win in a fight - a community of practitioners with skin in the game, or academic scientists with peer-reviewed studies?"

And then you use peer reviewed studies to determine who is winning. This is not a fair comparison.

It would be better to have a real world survivor threshold, like who makes it to the pro level and then see what they are doing.

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I think there a couple of confounders going unmentioned.

First, the age confounder. Older body builders with bad advice they got from their mentors probably aren't as present in online forums. Younger body builders are probably more tech savvy, reading everything they can and so more up to date on the science. So the populations being surveyed aren't the same back in 2011 and now, ie. science advances one funeral at a time.

Second, body builders use more "intuitive" cues to guide their training. For instance, the mind-muscle connection, which is now getting some empirical support, but also the pump which we see can lead you astray. These are exactly the immediate feedback mechanisms that you discuss (the pump makes you look immediately huge). However, it leads you to discount the empirical support because it seems to contradict what you see and how you feel internally.

Finally, by your own description, the lifting community only accepted the science because of a concerted campaign from researchers to correct the situation. Absent this, it's not clear that it would have changed on such a rapid timeline.

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I have relatively low confidence in either formal academic research or folk wisdom in healthy lifestyle questions beyond the basics. The broad outline of a healthy diet, yes, but anything more specific like high or low carbs vs fats seems very dubious and indeed the formal literature seems to vary considerably. In a sense this is unsurprising, it is hard to get compliance and rct are hard if not impossible to do with any sufficient number of people. There is wide interpersonal variation.

Weightlifting suffers from similar problems.

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The popular, free weight training program StrongLifts 5x5 recommends 90 second rests if your set was easy and 3 minutes if it was hard. It's even built into their app.

I've never even questioned it. I just assumed the designer of the program was as reasonably well informed as you could expect a broscientist to be. Pleasantly surprised.

Oh, maybe this doesn't apply because body building is not the same as weight training? Body building is about getting big muscles first and foremost. Weight training is about Health Benefits ™

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Soviet era Olympic and general amateur/pro athletics programs might offer some really interesting follow-on research. As the rules were different there, successful coaches were able to experiment on a controlled population (their athletes) on what methods did or did not work, with the athletes having much less say. I wonder/bet you could dig up an example of a Soviet era coach using a control group + and not, and with those coaches operating somewhat on gut instinct/bro science themselves. Modern strength programs also blur that serious science<>bro science line too (control group == last season’s players).

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"The most important lesson I draw from this is that metis and a community doing practical work doesn’t put you above academic science and peer-reviewed results (or at least it doesn’t always put you there)."

Counterpoint: Have you considered that both metis and academic science are equally valid ways of knowing? (Yes, this is a serious position many academics hold).

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Ingredients for muscularity, in order of importance: genes, low body fat, lifting.

Fixed it for you.

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Could it be that short rest periods result in a more satisfying pump and less time spent at the gym, making it more likely someone sticks with a bodybuilding routine, thus making more “gainz” than the long rest period people?

The gym bro’s advice might actually be optimal in an uncontrolled environment.

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There are a lot of great comments on here and I'm pleasantly surprised to see so many ACX readers lift recreationally and seem pretty up to speed on the culture and the science.

The one thing I haven't seen mentioned yet is the asymptotic nature of strength and hypertrophy gains. The nature of the game is, no matter what, you have a pretty hard limit on how big and how strong you are ever going to get. That limit is set genetically and about all you can do to manipulate it is use anabolic steroids, but that simply pushes the limit higher. You still have a limit.

This leaves you in a situation where "skin in the game" doesn't necessarily leave you with incentives to select the absolute maximally productive program. The first reason that has already been discussed well in other comments is that, overwhelmingly, what matters more than anything else is long term consistency. If you lift for ten years without fail, you have some chance of achieving your genetic limit. If you lift in fits and spurts and constantly give up, no matter how optimally you progress when you're lifting, you'll never get anywhere near your genetic limit. So the top performers are all people who have been in the game for a long time and stuck with it. Thus, the very first concern when choosing how to train is will you stick with it?

The second reason that I haven't seen discussed yet is that having a hard limit on what you can ever achieve in one lifetime means many different programs will all get you there as long as you stick with it. Training more optimally can only get you there slightly faster. You're inevitably going to peak at some point. This isn't like investment or betting strategies that have potentially boundless returns. If you watch Pumping Iron, you'll see Arnold doing a lot of stuff that likely doesn't quite pass scientific muster. He was quite obsessed with feeling a pump and did a lot of low-intensity, low-rest work. What difference did that make? He was as genetically blessed as anyone who ever lived, had access to drugs as good as anyone else so that was not a discriminator, and he'd been training since he was a kid. By the time that documentary was filmed, he was never going to get any bigger no matter what he did (unless he was willing to sacrifice leanness, but that defeats the purpose of competitive bodybuilding).

Consider Arnold started lifting at 15 and first won Mr. Universe at 20. If he had been just a little bit more Bayesian in his approach to programming, then what? Could he have won at 19 instead? How much of a difference does that actually make? He has had the most pinnacle dream life any reasonable person could ever hope to have either way.

The one thing nearly everyone on bodybuilding.com gets right, no matter what else they do, is to join a community at all and publicly commit to demonstrating their progress. Even if what they end up doing is stupid in nearly every other way, "lift something at all on a regular basis" gets you 80% of the way there, which is 80% further than the average coach potato American.

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Forums aren't the right place to find out bro science. Go to the gym as a scrawny person, look like you're learning how to benchpress, and the bros will come to you (very aggressively - personal experience). Ask them about rest periods.

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If you're lifting using a machine at a reasonably busy public gym there's the issue that somebody might be waiting for the machine. If you have seriously long rests then to the other observers it won't look like you're resting between sets and will look more like you're sitting on the machine just because

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I've been a thrower (the track & field kind) for all my life, and the incremental improvement of the world record is a good example of Metis. Throwing events are sufficiently unimportant for anybody to bother conducting scientific studies about them, but they're important enough for thousands and thousands of people trying to get better them all over the world (lots of people train for High school track, NCAA, Olympics etc).

Take the hammer throw as an example: the world record in 1913 was 57.77m, and by 1986 it was 86.74m. That's a 50% improvement, which is quite amazing considering human biology is consistent. Some of the advancement was "passed down" from our scientific overlords - like steroids, nutrition, and how to do strength training (although much of that was also word-of-mouth). But the hammer throw is extra interesting because that 50% improvement is not seen in other events, like the 100m dash (where they also made use of steroids, nutrition, and strength training). They only saw a 10% improvement between 1911 and 2009. So what's up with the remaining 40% found in the hammer?

Part of it is that hammer throwers are stronger, so extra steroids, nutrition, and weight training helps them more than it helps 100m runners, but mostly it's because the hammer throw is a complex movement relative to running. So hammer throwers made lots of technological progress and all of that knowledge was passed on through Metis. Basically, none of it is the product of the scientific method, and none was published. It was about people trying new things, seeing what made the hammer fly farther, and coaches passing that knowledge onto the next generation athletes. So when I started my career, I and my dad went around the country to meet up with knowledgeable throwers and coaches, who in turn had been taught by people before them. And by the time I was 16, I threw what would have been a world record in 1950, and by age 20 I threw what would've been the world record in 1960. And I'm not tooting my own horn here - literally thousands have thrown that far, and it's because of knowledge being passed on.

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I've long thought that comparing the 'practical wisdom' communities with supposedly numerical, Occidental forms of acquiring knowledge is a false dichotomy - given that arguably all knowledge is built upon the basis of forebears, including Western science. Instead, the argument is more accurately an attempt to contrast advanced, scientific methodology with what is tantamount to argumentum ad antiquitatem at best, and long-surpassed evolutionary adaptation at worst - i.e., watch the members of the tribe who die during the process of cooking/eating that plant, and avoid following their methods.

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What I really want to know is - what about 10 minutes rest? 30 minutes? 2 hours?

I have my weights in the garden and I do sets throughout the day whenever inspiration strikes. Surely, there's gotta be a difference there. Do I need to do significantly more sets to compensate for the long breaks?

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I think Taleb might argue that SA did not focus on an appropriately anti fragile metis group. For example, old dog Russian kettlebell practitioners who focused obsessively on practice/technique and long rest times for over a century didnt need randomized control trials to know they were being effective (most modern American gym rats are a different story).

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Can someone explain the "strength vs. bigger muscles" thing to me? How can smaller muscles be stronger than larger muscles (on the same person, that is; interperson/species mechanics will obviously differ)?

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I think you’ve got it exactly right, that bodybuilders, far from eschewing science, are reading anything they can get their hands on to gain an advantage, which means when that science is wrong it’s going to lead people astray. I think one answer to why the feedback loop didn’t help is the failure modes weren’t dramatic enough. Lifting with short rest periods still builds muscle. Just sometimes marginally less than more rest. But the main downsides are unnecessary pain, so there aren’t really the same selective pressures you’d see if short rest turned everybody into 98 pound weaklings. (Also, steroids can mask a lot of the downsides;)

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I am a lifter who also happens to be a physicist with OCD tendencies so I try to collect data to support what I am doing, trying out things that people tell me about. My favourite lift is the deadlift.

With deadlifts I tried some fixed recovery periods (2, 3, 4 and 5 minutes) and discovered that 5 minutes was far too long between my first and second set and two minutes was far to short between my fourth and fifth set (systemic fatigue being the limit). I moved from fixed times between sets to measuring recovery between sets based on heart rate, my next set starts when my heart rate hits my target recovery value. In practice this means that if I am doing five sets of five deadlifts above 90% of my 1 rep maximum there will be only 90 seconds between my first and second work sets, 120-150 seconds between my second and my third, 180-210 seconds between my third and fourth and 300 seconds or more between my fourth and fifth sets.

While I am still collecting data on how my body recovers after sets, this has been interrupted by the gyms being closed in my city, so I am restricted to dumbbell front squats in my home.

On my first set my heart rate will rise to a maximum and then cleanly and quickly recover (with something like a 20 bpm difference between peak and trough). On my second set the rising part of the curve will look the same, but my recovery will take a little longer and pause on the way down. Subsequent sets develop odd features where there is a second peak in my heart rate while I am recovering, my heart rate will start to drop then rise again, eventually the second effort peak will be higher while I am recovering than while I am actually working out. Systemic fatigue accumulates and takes longer and longer to clear.

In any one session, how much systemic fatigue you accumulate doesn't make too much difference if you are actually into the feeling of working out, but over time, it makes it harder and harder to start the next heavy workout session. You can only make serious gains if you actually manage your fatigue.

Anything that stops you from doing the next session will limit your ability to make any gains.

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I’m a little confused here about the grounds of debate. If we wanted to test Taleb’s assertion that metis outperforms academic knowledge, the kind of experiment I’d imagine would look something like having group A spend a couple months reading scientific literature about strength training, and group B spend a couple months hanging out with bodybuilders, have both groups develop and execute practice regimes, and then have a competition between group A and B and see who does better.

Instead, this post evaluates the performance of the body building community’s metis not by objective outcome, but by *how well it aligns with the current state of the scientific consensus*. Isn’t that assuming the conclusion? If the criterion is “how well does metis match the conclusions of peer-reviewed studies”, of course the outcome will be “less well than the most recent peer-reviewed studies”.

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"In 2005, Ahtiainen et al. found similar muscle growth when training with 5 vs. 2-minute rest periods. Importantly, this study was work equated, which meant the shorter rest period group performed an average of one extra set for each exercise to compensate for their lower work capacity."

Shouldn't it be the longer rest period group or am I reading things wrong?

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I have a good idea for a Thing You Will Regret Writing: do this same sort of analysis looking at the breastfeeding literature and the claims of GPs/lactation consultants. The latter groups are still heavily promoting breatsfeeding on the basis of putative long-term benefits shown in old-school OLS studies. Those long-term benefits are nonexistent in a set of recent, methodologically superior "discordant sibling" studies that use family effects to control for SES and parental IQ.

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But, but, but.... internet forums about sport attract nerd(ier) types who are interested in the science. Ditto people that write about this stuff on their websites.

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I must admit, I too am taken aback by this revelation. However, in retrospect, considering his previous website was named https://fitover40dallas.com/, perhaps it's not as far-fetched as it initially seemed.

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