This article has a bad "pop science" feel to it. The correlation between grip and survival is probably solid enough, but it's hard to avoid the nagging feeling that people who have a strong grip are probably stronger and healthier overall as well.
The article goes on to recommend grip strengthener and I strongly suspect that better skeletal-muscular health in general should be the goal.
"Strong people are harder to kill than weak people and more useful in general." --Mark Rippetoe.
Yes. The correct take from this article is to change your lifestyle until you have strong hands if you want to live longer, but don't focus on getting strong hands specifically.
Yup. The right lifestyle leads to all sorts of beneficial side effects. I moved off grid about two years ago, and since, have become leaner and fitter than I have been in my entire life, with zero deliberate exercise. I hadn’t considered my hand strength until just now, but it just occurred to me that I’ve had no carpal tunnel symptoms in at least a year, although I still do plenty of typing and fine manual work. I also do a lot of heavy carrying and lifting and digging and all the rest. Prior to this I was a desk jockey, living off processed crap - now, barely a day passes when I don’t find myself doing some kind of manual labour out of necessity. Honestly, it feels great to live like a human is built to live. We just aren’t made for the sedentary lifestyles we typically live in developed countries, and it’s killing us - and advice like “use a hand exerciser” is the absolute epitome of treating the symptom, not the disease.
I generally love Axios, but this does feel more life hacking newsletter than hard news.
But the article does talk about risk of falling too which. seems like a fair logical causation jump that stronger hands = less risk of falling injury. They don't cite that though....
I think they should have used the line from the harvard link they put "these findings highlight the importance of doing regular exercise to maintain strong muscles as you age. "
Which is fairly impractical over those timespans and so we mostly have to make do with observational studies and RCTs looking at proxies for the actual outcome of interest and mechanistic reasoning.
I definitely agree with this. When I was a beginner weightlifter, I'd actually grip the bar too tightly. This led to bicep activation when doing bench press, so I had to learn to lighten my grip and focus on activation of my deltoids, pectoral muscle, lats, etc. Even some tricep activation helped too
Yes I believe you are correct here. So often in medicine we want to just treat the symptoms. It's amazing how hard it is to find doctors who don't end up thinking like this. Personally I haven't been able to figure it out. They're definitely not stupid, but why do so many research papers look at the body in such a way that leads to such prescriptions? Is it because researchers lack the clinical experience to overcome this mistake?
Definitely the advice of increasing one's grip strength is poor on multiple levels. Even if increasing your grip strength leads to a higher-quality life, simply training only the forearm without addressing the entire arm and shoulder and neck all together is not going to be good for ones overall muscular (and nerves, etc) balance.
No way man, the entire medical industry is well aware about the differences between correlation and causation.
Trials to validate medicine heavily involve tactics to check for causation.
What you're reading here is just some journal that identified a correlation and the author of the popular science article can't tell the difference between that and causation.
I think it is probably fair to say that the industry is aware, but most of the practitioners that make up the industry can still be susceptible to the mistake. This is largely true of science, as well.
Note that I don't mean that many practitioners are ignorant of the idea. I mean that they could know it, and still fall to it. "Value based judgements" are still a large thing, after all.
Practitioners just regurgitate the results of said science. They use standard treatments and well-documented techniques without the need to understand the science around the development of those techniques.
Hacker News’ automatic removal of “How” from article titles can really change the meaning. The modified title looks like a strong, scientific claim. So we end up with lots of obvious ‘Science 101’ comments about correlation vs causation etc.
With “How” in the title, it comes across as what it is: a light popsci/lifestyle piece that should be taken with a grain of salt, but might still contain interesting food for thought/discussion.
OTOH, there is just correlation in an otherwise minimal article. The only support, two very similar articles, is pure correlation, and both are based on all adults, not just elderly. The jump to "it lengthens your life" is made on a single quote.
But there isn't just a correlation. There's also a fascinating idea: better grip strength might help prevent a common cause of death in old age: falls. I've never made that connection before, but it seems very reasonable now I think of it, and compelling in its implications. That's good enough for me to want to discuss it, maybe even to motivate me to work on my grip strength.
If someone ever brings me evidence that having stronger grip does not help you avoid falls, then (a) that would be surprising and interesting, and (b) I wouldn't feel like a fool for having improved my grip strength anyway.
Empirically proving causation is often difficult or impossible. It's irrational to expect every potentially useful idea to meet that high bar before taking it into consideration. If someone is trying to sell me something, or if the idea goes against common sense, I'll demand proof, but that's not the case here.
It's an old study, but correlation doesn't prove causation. It turns out that people who have pore hand/grip strength are more likely to fall, or have a type of life that leads to higher chance of death.
This is a very complicated cause/effect to figure out, even for top-class physical therapists.
Also possible that if you have good grip strength then you have good muscular balance and innervation, vascularity, and motor neuron balance (extensor/flexor), which possibly leads to better overall health, including heart health.
Honestly, I have no idea. But that's the point. Neither do experts who spend decades in this field. It's far too complex to study through these types of lenses. This is often why clinical practice still does better than science in this field. It's complicated as hell and many traditional scientists think they can study the musculoskeletal system this way, when the top doctors learn most of their skills through clinical trial-and-error. Still in 2022.
Just to attempt to be thorough, and reiterate that honestly I don't know the answer, but good grip strength may be something comes from good overall muscular and nervous system health, not the other way around.
It interests me how far we have come in technology, but how little we know how to apply it to certain kinds of medicine.
Just as an anecdote, I have been spending thousands of hours in physical therapy, and have visited doctors all over. One thing I have learned is that many great doctors used to read tonnes of research papers early in their career, but over time gravitated more towards their clinical experience in building their tree of knowledge. From what I have heard, the science is just too vague and difficult in this field and so as tempting as it is to want to apply the scientific framework around this field (I'm talking specifically about physical therapy here, not necessarily other areas of medicine where I know far less about), it ends up being more effective to build up ones intuition off of a strong clinical practice and then to look at the science afterwards in order to calibrate and filter through those experiences.
A bit of a tangent, but something I also find to be interesting is how poor the feedback mechanisms are in a lot of medicine. Most patients don't follow their prescribed homework, and many surgeons don't even get to see the long-term outcomes of their patients' surgery. Or when they do they are measuring some variables that don't give enough of an overall view of the person's body or overall health.
Anyways, I'm done rambling for now :P. I hope we can curtail the upcoming health crisis we are going to have with our and our childrens' postures and poor body mechanics.
"Most patients don't follow their prescribed homework, and many surgeons don't even get to see the long-term outcomes of their patients' surgery."
I had some problems after sports accidents and after an odysee to different surgeons and co. and an operation, I came to the conclusion, that the lowly, but very experienced physical therapists, offered the best advice for me. Because they actually work closely with the patients in the long run and see what works. But since they are not academics, it seems their opinions are usually not very well regarded and do not move up the chain (at least here in germany, but I can imagine it is the same all around the world).
To be frank, most doctors don't perform the same exercise that they recommend to their patients themselves. Leading by example should be a thing.
I am now in care of a fit doctor who, though being over 50, is slim and obviously active. It is a huge difference from my previous doctor who was visibly overweight even though 10 years younger than me, and from the yet previous doctor who tipped the scale at at least 350 pounds. (That one died of Covid after spending 6 weeks in the ICU. Wasn't yet sixty.)
If the fit doctor recommends me something from her own experience (in her case, the Sun Salutation), I will know that it works.
" good grip strength may be something comes from good overall muscular and nervous system health"
There probably is a circular relationship. Enough physical activity leads to better cardovascular health and stronger muscles. Those lead to good grip strength, which is just the best measurable element of overall physical strength. Stronger people have more capacity for exercise and will engage in more physical activity, which leads to better health etc. One day, some equilibrium is reached, but this equilibrium is much better than in sedentary people. This equilibrium lowers your risk of heart disease, the worst of modern age killers.
Also, if you spend time outdoors (and a lot of physical activity is done outdoors in favorable climates), your immune system gets training, too. And immune system is what seems to be protecting us from cancer, the second worst of modern age killers.
>This is a very complicated cause/effect to figure out, even for top-class physical therapists.
Have you ever wondered what kind of experiment is needed to be run in order to verify causation?
I see people say "correlation does not equal causation." And they never wonder, well what exactly is causation and how can science attempt to verify it at all? One person even told me that causation is impossible to verify. He's right on a technical level. If you want to be very pedantic science cannot prove anything to be true. But pedantry aside experimental methods to "prove" causation are very real and used extensively in the medical industry. All the medicine you put in your body (including the covid vaccine) is verified to be effective from a causative standpoint.
That being said the experiment to test for whether or not hand/grip and strength causatively effects life span is quite trivial in terms of planning out what has to be done. The study could take a while but we've done other studies that have lasted longer and are far more complicated.
Simply select a random group of people and put half of them on a daily plan to increase grip strength. If the half that was put on a daily plan generally lives longer than the other half of people who weren't put on a plan you have verified causation. The key to proving causation is to have the experimenters hand controlling the causative factor rather than observing it.
This technique can (and often is) used to produce raw science directly from clinical practice. The term for this is called "clinical trials"
Not necessarily. It's possible that the group that works on increasing their grip strength will also become healthier overall in other ways. The grip strength exercises might motivate them to do other things that are good for them, body their mood, etc.
I am describing the technical way of verifying causation. This is how it's done in formal science. I'm not making this stuff up.
>The grip strength exercises might motivate them to do other things that are good for them, body their mood, etc.
Grip strength is still the causative factor here. It "causes" people to be motivated which in turn causes people to live longer. It literally supports the articles main point.
People are saying that correlation does not equal causation and that training for grip strength will not increase your lifespan.
However if the scenario you describe above is true. Then training for grip strength DOES increase your lifespan. Causation verified. The article is then completely correct. Think about it.
I get where you're coming from though. Being born has a causative association with having a longer life span than not being born. The connection is technically causative but you want to find a more direct source that is lower on the chain of causation.
This reminds me that whole thing where some study showed a comparison of average daily alcohol consumption and showed that "moderate" drinkers actually had lower mortality than those who don't drink (obviously heavy drinkers had _much_ higher mortality).
Little did anyone seem to realize that people who don't drink may be abstaining for health reasons and thus may be more likely to die / get sick regardless.
Not only that those who abstain do so for health reasons, but many teetotalers were in the past alcoholics. Those who have never had a drinking problem tend to have few qualms with a glass of wine here or there, and so could be classified as light/occasional drinkers.
The other explanation is that being a 'moderate' drinker correlates with being able to do things in moderation in general, which is predictive of longevity.
OK, maybe there's something to being able to catch yourself when falling, or prevent the fall in the first place through grip strength. But this:
> It's not just bracing yourself. Scientists have linked stronger hands to healthier hearts.
> One study in the American Journal of Preventive Medicine found that higher grip strength was correlated to lower blood pressure, lower blood sugar and higher good cholesterol levels.
Has to just be grip strength correlating with activity level and general health, not grip strength causing any of that.
Submitter said: “EDIT 2: Some of the very low values are individuals with disabilities”, “EDIT 4: Grip strength is a decent proxy for upper and lower limb strength, and is also correlated with other indices of strength.”
Well, it doesn't have to be that abstract. Muscles in the peripheral limbs, particularly the lower leg but also the forearm, are important in returning venous blood to the heart. In fact, the gastrocnemius (calf muscle) has been referred to as the "second heart":
People pointing out correlation != causation are missing the point.
CORRELATION AN IMPORTANT FACTOR HERE.
Say you are caring for a population of elderly people and you need to triage who to give more stability support (say carers, walking aids, etc). Do a grip strength test! The correlation is important, it doesn't matter if the correlation is causal in nature.
I challenge you dear reader, the next time there's a science article presented, to think about something more interesting to say than "correlation != causation". I challenge you to find useful ways that correlations can be harnessed.
On the other hand, people repeating "correlation != causation" ad nauseam is, in my opinion, one of the great success stories of science communication. Proving causation is the singular most difficult general problem across many scientific disciplines, and at the same time our brains are hardwired to conflate correlation with causation. I think that it's simply awesome that so many people are aware of this issue nowadays.
People mindlessly parroting anything is not a great success of anything, especially not of science communication. There is also no hardwired conflation of correlation with causation, it's just a general jumping to conclusions error.
> There is also no hardwired conflation of correlation with causation, it's just a general jumping to conclusions error.
There is plenty of literature in the neuroscience and psychology fields that show we are biased towards finding patterns where there are none. Evolutionarily speaking, this is easy to understand. Better to run away one extra time, than getting eaten by a lion. The latter is less likely to pass on their genes.
> People mindlessly parroting anything is not a great success of anything, especially not of science communication.
I respectfully disagree. Appreciating the subtleties of causality is beyond what you can expect from most lay people. Even many of my machine learning colleagues can get tripped up by this stuff. So even if it is simplistic, I still think it is useful that people at least understand that causality is difficult.
Well, both really. But in practice, erroneously identifying correlations doesn't tend to be quite so big a problem as conflating correlation with causation. The former is easy to address with strict data recording, whereas the latter is more of a conceptual thing, and requires some deeper thinking that often goes against intuition.
This statement makes no sense at all. Pattern recognition applies to any data. That's not even contested terminology. (besides, just redefine your processed data to be your new raw data, and you're back to square one...and in many cases it wouldn't even be clear how to precisely define unprocessed data)
Ok, what I meant to say it's a much more fundamental mechanism of cognition that has to do with processing perceptual information, while the other is a conceptual, logical mistake.
Ok. But no matter what terminology you want to use, it is still the case that there is plenty of literature that shows we are biased towards conflating correlation with causation. That is fact, not opinion.
If you want to criticise the evidence in the literature, then fair enough I guess...that's beyond me to defend.
Social science, health, and psychological research is 90% bad because of the correlation = causation fallacy, especially articles that claim to have "controlled for" X, Y, and Z. Even after controlling most of these studies still incorrectly suggest causation.
So by default, people are correct to mindlessly parrot this, even if they don't understand when they're wrong or misapplying the maxim.
ah yes, if they could only remember that correlation !== causation, 90% of social science, health and psychological research would become good instead of bad
It's not that difficult. It is "difficult" in the sense that many of the experiments to prove causation are cost prohibitive. But coming up with the experimental parameters needed to verify causation are trivial.
In fact, ALL clinical trials for all medicine are designed to verify causation. It's that straightforward. It just happens to cost a lot of money. Think about that. Why are clinical trials much more expensive than say the experiment correlating grip strength and life span? What is the differentiating factor?
This is the key. If you don't understand why/how clinical trials verify causation and what exactly is the differentiator between experiments that only correlate things then you don't truly understand the dichotomy between correlation and causation.
Most people don't understand it. Even the programming crowd. I even met data scientists who don't know about it.
While the correlation here turns grip strength into a useful diagnostic sign to stratify patients into risk groups for possible intervention (assistive devices etc.) the authors go on to advise the reader on improving their grip strength, on the implied hypothesis that doing so will reduce the adverse outcomes enumerated earlier in the article. Possibly the effectiveness of that sort of intervention is already know but the whiff of “correlation != causation” for me was only around that question. Possibly that too is already known; I don’t know that literature. But the authors don’t draw that connection and therefore leave the question of correlation and causation open at least from the perspective of their recommended interventions.
Correlation DOES IMPLY causation somewhere. It's just the causative source may not be part of the experimental parameters.
Think about it. Hand grip and longer lifespan. For those two things to correlate they MUST at the very least be connected by one or several causative sources. There is no other logical explanation for it.
It's just this source isn't part of the experimental parameters.
On the other side of the coin if two things Do NOT correlate, it heavily implies no causative connection at all.
> I challenge you dear reader, the next time there's a science article presented, to think about something more interesting to say than "correlation != causation".
I challenge the writers of articles to write articles which doesn’t walk into this problem.
> Say you are caring for a population of elderly people and you need to triage who to give more stability support (say carers, walking aids, etc). Do a grip strength test!
But that’s not what the article says, does it?
“The single most effective set of muscles you can work to extend your life is in your hands.”
This is the first line of the article, and it is completely unsupported by data or studies. So how are we missing the point?
> The correlation is important, it doesn't matter if the correlation is causal in nature.
But it does matter! If it is causal then we should give hand strengthening devices to everyone. We should have fun hand strength competitions in social settings to encurage everyone to care about their grip strength.
If it is not casual then we can use it as a diagnostic indicator precisely as you say. In that case it is actually a bad idea to encourage people to strenghten their grip, because that might break the correlation between ill-health and grip strength, thus ruining the diagnostic indicator without helping anyone to live a healthier life.
How can you say it doesn’t matter if the correct reaction differs this much?
Hand strength is correlated with exercise. Legs tend to be strong in general for modern people because in the end we still walk and the legs have to carry the whole weight of the body - which tends to be significant. But hands will be strong only if you voluntarily exercise. Even physically demanding labour tends to have many tools to make hand oriented tasks(hand jobs?!) considerably easier. So if you can't/didn't control for this correlation, there is no news here.
Also, playing golf adds 5 years to your life expectancy [1]. I kid you not. Start playing today, and you’ll live years longer. This has nothing to do with the fact that most golf players are really wealthy, and so they have access to way better healthcare, nutrition, and lifestyle than the rest of us.
Said differently, correlation does not imply causation.
Similarly, a diagnosis of in situ prostate cancer means you'll have less risk of dying[1] over the next ten years compared to the rest of your age and race group. Totally not because men who catch these cancers early have good health insurance, regularly see their doctor, and keep up with screening procedures, plus all the other behaviors associated with those personality types.
[1] If you look at the U.S. national statistics, net cancer survival rates top out at 100%. That's because their algorithm doesn't allow any negative values for risk. I think that's enforcing a belief on the data, so I've always calculated it differently. People diagnosed with in situ prostate cancer, in situ testicle cancer, and (IIRC) in situ melanoma all have better survival chances than their peers. Unsurprisingly, all are screenable and easily treated if caught early.
I saw a study like that a year or two ago. It wasn't just correlation, they did an actual clinical trial. They measured BP before intervention, had people do a specific exercise to increase hand strength, had a control group, and measured everybody afterwards.
Not knowing the cause doesn’t mean much, in terms of valid association, unless the effect deviates as people adopt the correlating behavior. If we don’t know the mechanism but it continues to produce the same result absent other unrelated factors, it’s likely in the chain or determining factors.
They claim that was adjusted for socioeconomic status.
Rather than being a matter of better access to health care etc, I suspect a reverse causation -- people who are in poor health are less likely to go out to the golf course. The same applies to Vitamin D, taking international flights, and reading books, all of which are correlated with reduced death rates.
Thank you. They always make it sound like X helps you lenghten your life. But it's always the case the X is a symptom of a healthy life, not the cause of it.
Strong hands is probably a result of exercise and leading a healthy life which leads to higher life expectancy. Meaning exercise and leading a healthy life is the cause of strong hands and higher life expectancy.
Golf industry says golf lengthens your life. Hand grip industry says strong hands lengthen life. Can't help but be a little bit cynical the older I get.
I would imagine few people with a strong grip have everything else in their body weak.
So a strong grip might correlate with strong everything else. By the way, strong hands are controlled by strings and pulleys - it's really just strong forearm muscles.
It would be interesting if the study was for people with JUST a strong grip, like folks who were always in a chair.
I remember reading of another study where people who were pear-shaped were healthier than people who were round. Turns out that people put on weight at the waist first, and as they put on more weight, it moves to the chest and shoulders, so...
The page you linked should but doesn't reference the actual study. The mortality reduction from non-golfers changed according to golf handicap not just according to playing golf.
"Golf: a game of life and death – reduced mortality in Swedish golf players" by B. Farahmand, G. Broman, U. De Faire, D. Vågerö, A. Ahlbom.
"Golfers with the lowest handicap (the most skilled players) had the lowest mortality; SMR=0.53 (95% CI: 0.41–0.67) compared with 0.68 (95% CI: 0.61–0.75) for those with the highest handicap. While we cannot conclude with certainty that all the 40% decreased mortality rates are explained by the physical activity associated with playing golf, we conclude that most likely this is part of the explanation. To put the observed mortality reduction in context, it may be noted that a 40% reduction of mortality rates corresponds to an increase in life expectancy of about 5 years." [1]
They hypothesize two reasonable mechanisms for increasing health:
>Stronger hands grip tighter to prevent falls — and brace stronger when you tumble.
>Grip strength is especially important for those older adults who use canes, walkers or handrails or need assistance getting out of chairs, says David Bellar, a kinesiologist at UNC Charlotte.
I own the No.2 model[1] and have been squeezing it for a year. It's fun, mostly for handing it to tough guys and presenting it as The Pansy Test. Out of over a dozen grown men, none have closed it yet. Inevitably they eventually ask me if I can, to which I humbly reply "I think so." and do it several times. They always want to try again, some get mad. I'm small and insubstantial. That can be amusing.
But I've never perceived any benefit from using it.
Squats are where it's at, I think. I see a change in my overall form more dramatic than any other activity, except maybe hard labor.
CoC grip trainers, a trip down the memory lane. I got certified for the #3 almost 20 year ago. I could do probably 8-10 complete reps at the time. The #4 felt like squeezing a brick, I am wondering whether with a couple of years of training I'd been able to close it, back in the day probably just 2 or 3 people had been able to: Joe Kinney and one or two of those guys from Wales.
I also had a welder build some specific grip training equipment for me.
I doubt I'd ever be able to close the #3. I've never done more than 4 reps on the #2. But I don't push myself. I seem to get much more out of pullups and other grip exercises. They're still great to have around and my favorite is their Zenith, which is softer than the #1.5, smooth-handled and fatter. If you can close a #3, you could close the Zenith telekinetically.
I did a specific training that took me a few months (3 to 5, difficult to remember, I had bought the program online, we are talking 2002), with plenty of negatives included that worked very well. I also had to file down a gripper to make the range of motion larger--the negative rep (which means closing with two hands, and open the hand, that is doing the eccentric part of the movement, slowly) in the "filed down" region was particularly effective.
If you could do 4 reps with a #2 with no specific training, I am confident that with targeted training and progression within a year you will be able to close #3. Worthwhile? I don't know. But closing #3 was as satisfying as getting my black belt in jiu-jitsu.
I'd take the black belt a million times over. That's a rare and magnificent treasure, where skill easily trumps strength. It is also extremely difficult to acquire.
It's really hard to get a black belt, it took me 10 years of consistent training in the art and a year after getting it I still don't feel like I'm good enough. That's okay, because it keeps me on my toes: when I feel like I don't want to train, whether it's jiu-jitsu, boxing, cardio or weightlifting, I'm reminded that I have a black belt and I need to "honor" it.
But feelings are feelings, I got a PhD in three years, close a #3 CoC in 6-9 months after getting them, and I got a black belt in 10 years. In terms of "joy of accomplishment," I would put 1) black belt, 2) CoC #3, 3) PhD.
It took me long time to get to 3, but did if after all (but just with right hand, left hand still on 2.5). That to be said, grippers may not be accurate, each one a bit off - there was a company (can't remember the name) where you can send your gripper to be measured, and returned back.
I have a generic pair of the same design that I keep on my desk. For me, the benefits of using them during the day are:
1. Keeping a 35 year old wrist injury at bay. Even just a few squeezes during the day “unlocks” my wrist which otherwise gets tight from a day of typing.
2. Helping me stay focused during long video calls. If I’m squeezing them in both hands I can’t be wandering over to sites like HN.
It’s hard to work your hands for strength without working other significant muscle groups at the same time—like hanging from things or picking things up.
Likewise, it’s hard to work on muscular strength without also increasing your hand strength. To lift weights, your hands have to grip the weight.
So, there is a pretty strong correlation with overall health.
The one thing I’ll say is that hand strength is hard to get back if you let it fade. The muscles don’t grow very fast or very much, and you need strong tendons (which grow even more slowly) to transmit the strength to your actual fingers. So again, if you’re able to increase hand strength, you’ve probably got some other positive correlations like “works out regularly” and “cares about functional health.”
Yep, you read this as being a correlation-causation fallacy. You are being nerd-sniped, and it worked. Don't let that put you off doing arm and hand exercises. I recommend kettlebells.
Everyone knows correlation does not equal causation.
But no one knows the nature of the statistical experiment that is needed to prove causation. Ask yourself this before you post a new flavor of the "correlation does not imply causation" post that is already all over this thread.
So we know correlating hand strength with lifespan doesn't prove causation. What sort of experiment or what different parameters must be changed in order to verify causation? If you don't know the answer to this, then that means you don't completely understand the dichotomy between correlation and causation.
Find (or create) lots of obese people or smokers or alcoholics focusing only on hand strength exercises. Then see how their life expectancy changes compared to obese people, smokers or alcoholics that didn't do those hand strength exercises.
>Find (or create) lots of obese people or smokers or alcoholics focusing only on hand strength exercises.
It's clear you don't see it. You don't have to focus on smokers or alcoholics that's irrelevant.
But let's modify your statement to not include the fluff.
>Find (or create) lots of people who focus only on hand strength exercises.
Even when you remove the fluff the statement above still shows how you don't understand the dichotomy between correlation and causation. The experiment in the article can in fact be summarized by this statement:
>Find lots of people who focus only on hand strength exercises.
This statement cannot prove hand strength causes longer lifespan, you are right. However to test for causality is trivial. you simply need to do do this:
>(Create) lots of people who focus only on hand strength exercises.
It is the act of creation that forms the causative proof. Think about it.
If I took a random population and made them train for grip strength. Then I compared that groups lifespan to the overall lifespan of people I didn't make train for grip strength and I find that there is a correlation with longer life span for people who trained for grip strength...
Well I've just verified causation. There is literally no other conclusion. Try to come up with a scenario where the two factors are not connected causally. You can't.
By having the experimenters hand controlling the causative factor, you can prove correlation. If you are simply observing things with no control over experimental parameters, correlation is then impossible to verify.
It is the act of creation or controlling the experiment that allows for causation to be verified.
> If I took a random population and made them train for grip strength. Then I compared that groups lifespan to the overall lifespan of people I didn't make train for grip strength and I find that there is a correlation with longer life span for people who trained for grip strength...
Well I've just verified causation. There is literally no other conclusion.
What if the people you trained for grip strength also started taking care of their health in general (eg. eating better and moving more often), after starting your grip strengthening exercises?
>What if the people you trained for grip strength also started taking care of their health in general (eg. eating better and moving more often), after starting your grip strengthening exercises?
If caring more for their general health was "caused" by grip strength training than grip strength training is still causative for increasing lifespan.
Think about it. Prescribing grip strength training in this case will indeed increase lifespan if what I said above were true. But the claim people are making here is that the correlation has no causative relation... that prescribing grip strength training WILL NOT cause lifespan to increase.
In fact, everything the article claims is true if the scenario you described is real.
You're thinking about direct causation which is hard to define. If running increases heart health which increases lifespan... which caused lifespan to increase? Heart health or running? The most elegant definition is to say both do. But then again being born is causative to increased lifespan as well but making a statement saying birth causes increased lifespan isn't a meaningful statement.
The nature of causation is a chain of events leading all the way back to the beginning of time. All events in that chain caused the most recent event in the chain. Reality is, in fact, made up of single tree of causative events and multiple linked chains, where ancestors in the tree are said to be causative.
Sibling nodes and events that don't have an ancestor relationship at best can only share a correlation (aka common ancestor).
That would definitely explain the large numbers of feisty old Judoka I meet around the world. Anecdotally, there seems to be a higher percentage of healthy older individuals doing Judo than the general population, but I guess the unhealthy ones wouldn't still be at it, so it self selects for that trait.
Judo practitioners might be a good population to study for this effect, if you could find the individuals that started and track them all, including the dropouts. It would have common traits of strong grip AND muscle memory of how to fall properly, which could be a confounding factor.
My friend is an electrician with a monster grip - he still had a heart attack!
Sounds like a correlation that misses the point, general health prolongs life, couch-potatoes die sooner and have worse quality of life their last 30 years or so. And setting up for good health in advanced age starts decades earlier.
Try comparing someone who does grip-strength training only vs someone who does heavy dead-lifts, both into their 80s.
My money will be on the dead-lift guy, not just having a better quality of life until his last day, but also living longer.
While the website seems very fluff, the concept of hand health can't be overstressed.
Keep care of your hands and wrists. If you feel pain or discomfort, stiffness etc figure out why and fix it. Whether it's keyboard/desk etc change. Or taking breaks and stretching.
Those suffering later stages of hand/wrist strain or wear... look into:
wrist straps,
wax baths,
heated 'wax gloves'
I’m slightly embarrassed to admit that, in late and just post college, my wrist pain was so bad that I used to have to ice my wrists at night and take ibuprofen to be able to sleep. It didn’t occur to me at the time that I needed to do anything about it.
Eventually a colleague noticed and took me aside and gave my a clue-by-four to the head. 30 years later, pain-free and still in the industry, due in no small part to a Kinesis keyboard.
Regular mountain/rock climbing is probably a great way to improve your grip strength. Of course, regular outdoor climbing (even with a rope) may not reduce your lifetime risk of death from falling.
If people in science really do understand that correlation is not causation, why are they publishing papers in journals that show meaningless correlations without doing the actual work of uncovering patterns of causation? If you really understood this point you would be embarrassed to publish a paper on it. These results should be confined to a searchable database in the same way data sets in lab experiments are.
If you're trying to avoid death by falling, then strong hands won't save you if you don't know how to fall properly. As someone who grew up skateboarding, I had to learn how to fall properly to avoid constantly injuring myself.
There's a reason a lot of older skaters can still skate and I can tell you it's not because of their athleticism or healthy habits for which both are usually lacking.
I had a friend who worked in assisted living centers, and saw a number of deaths related to falling. The one thing he noticed about those that fell most frequently was that they still drank alcohol. Anecdata from someone in the field, but it was a stark reminder that people who get to an infirm stage in life are still just people, with all the same vices as before.
That's a strange title. Regarding falling. One of the most important things is to sit or lay down immediately when you feel bad, like nausea for example. I understand the fall can be sudden. But sometimes people have a couple of seconds to react and they look for a something nearby to hold on. But then they pass out and fall.
In a book (about the brain) I read. It made the case for using softer shoes or bare feet as we get older. The reasoning is that if you use hard shoes to navigate stairs, you lose the sensation of what you’re walking in making it more likely to have an accident.
The most common cause of death in my family is the secondary effects of a fall.
> Scientists have linked stronger hands to healthier hearts.
Erm, correlation is not causation, it's probably BECAUSE you have a healthy heart that you have a good grip on your hands. I can't believe it's not obvious to the author.
I dunno. I can squeeze Iron Mind #3 - but I don't consider myself that healthy, it's just a habit I've had. (Oh, I can squeeze it only with my right hand, my left is 2.5, almost to 3).
The XKCD article is a misnomer. Causation is actually verified.
1. You measure a population about whether they know about a fact. You find most people don't know it.
2. You introduce a statistics class to that population that teaches said fact.
3. You measure the population after the class and you find most now people know about said fact.
That is literally proving Causation. But you'll see there's a trick in my wording. If I didn't deliberately introduce that class to a population, and I simply observed an existing population that took that class... well, then in that case I cannot prove causation.
However the character that was asked the question in the XKCD comic, deliberately introduced the statistics class on himself. This deliberate act changes the experiment. HE himself is the experimenter and he controls the parameters and thus he has the knowledge needed to verify causation.
The person who asked the question cannot verify causation, but the person the question was asked too, CAN verify it.
I get the humor behind the comic. But it is technically wrong. Causation is verified. All causative experiments are run this way.
I am going to bookmark this article as a classic example of reporting so ill-informed that it confuses cause and effect, as described by Michael Crichton in characterizing “Gell-Mann Amnesia.”
Guys guys, the whole article was written just to feed traffic to the website selling the hand exercise devices, including the scam powerball thing, which was a cool product when it came out, but for years has had such poor quality control that the devices always stop working after about two hours of use.
The article goes on to recommend grip strengthener and I strongly suspect that better skeletal-muscular health in general should be the goal.
"Strong people are harder to kill than weak people and more useful in general." --Mark Rippetoe.