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Wisdom Wednesdays: A super simple measure that's a big predictor of your longevity · Hardiness with Dr Paul Taylor

• 0:09
  Speaker 1: Hey, everyone, welcome to another edition of Wisdom Wednesdays. Today's session,
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  Speaker 1: I am going to try to convince you to update
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  Speaker 1: your present list for Santa and stick a hand grip.
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  Speaker 2: Dynamometer on there.
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  Speaker 1: Now, you will have heard me talk before about strength
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  Speaker 1: training and muscle mass is critical to aging well. But
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  Speaker 1: today I want to talk about a really fascinating study
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  Speaker 1: that's just been published that really brings this point home
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  Speaker 1: and gives us a tool that is so simple, so cheap,
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  Speaker 1: and so powerful that it really should be in every
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  Speaker 1: gpage toolkit. Every time you go to the doctor, they
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  Speaker 1: should be measuring this, just like they measure your blood pressure.
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  Speaker 1: So the research paper in question has just been published
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  Speaker 1: in the American Journal of Preventative Cardiology and the title
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  Speaker 1: of the paper is Grip Strength to Weight Ratio all
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  Speaker 1: Cause and Cardiovascular mortality and Cardiovascular disease prevent Prevalence evidence
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  Speaker 1: from n Ham's and Charles. So what they did in
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  Speaker 1: this study was they looked at something called grip strength
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  Speaker 1: to weight ratio or GSWRS I will refer to it.
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  Speaker 1: And obviously it's a relationship with all cause mortality, cardiovascular death,
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  Speaker 1: and the prevalence of cardiovascular disease. Now, we've known for
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  Speaker 1: a while that grip strength is a useful biomarker, and
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  Speaker 1: I've talked about this before. It's been linked to everything
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  Speaker 1: from frailty prediction and falls, to heart disease, depression, and
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  Speaker 1: even a very strong linked to dementia. But absolute grip strength,
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  Speaker 1: like many things in health, isn't the full story. Because
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  Speaker 1: bigger people tend to have higher grip strength, but does
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  Speaker 1: that mean that they're healthier?
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  Speaker 2: Will not always.
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  Speaker 1: And what the researchers did in this study, which I loved,
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  Speaker 1: was they normalized grip strength to body weight to get
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  Speaker 1: a more individualized, more meaningful metric which they call GSWR
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  Speaker 1: grip strength to weight ratio, and that is basically how
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  Speaker 1: strong you are for your size, and that is a
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  Speaker 1: much better predictive value for an individual on an individual basis.
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  Speaker 1: So let's dive into the study. And what they did
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  Speaker 1: was they analyzed data from these two massive nationally representative
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  Speaker 1: cohorts and the US Enhange Study and the Chinese Charles Study,
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  Speaker 1: And between the two, we're talking over twenty thousand individuals
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  Speaker 1: that were followed for seven or eight years, and that's
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  Speaker 1: a pretty strong data set and Obviously they were older
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  Speaker 1: individuals because they were looking at things like cardiovascular these
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  Speaker 1: and all cause mortality. Now, strength was measured with a
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  Speaker 1: hand gripped dynamometer and you can actually buy them, and
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  Speaker 1: we bought one in our house about a year ago
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  Speaker 1: and a bit where we're using it.
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  Speaker 2: You can buy one in.
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  Speaker 1: Australia on Amazon for twenty nine Australian dollars. In the
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  Speaker 1: States have checked it up, you can buy one for
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  Speaker 1: nineteen US dollars and in the United Kingdom that come
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  Speaker 1: as cheap as seventeen quid. Right, And here's how to
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  Speaker 1: replicate what they did in the study. You get this dynamometer,
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  Speaker 1: which is basically something that you squeeze and it measures
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  Speaker 1: your force that you produce.
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  Speaker 2: Typically in kilos.
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  Speaker 1: And what you do is you stand upright and firmly
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  Speaker 1: grasping the dynamometer with your elbow flex at ninety degrees,
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  Speaker 1: so your kind of forearms sticking out from your body,
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  Speaker 1: and then you squeeze the dynamometer as hard as you
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  Speaker 1: possibly can for three to five seconds. And what it
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  Speaker 1: will do is will record the max force that you
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  Speaker 1: can produce, and typically it gives it in kilos. I'm
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  Speaker 1: not sure if the US ones do it in pounds.
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  Speaker 1: If it's pounds, then you just use that because it's normalized.
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  Speaker 1: And what you do is you do it twice for
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  Speaker 1: each hand, rest for thirty seconds in between, or you
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  Speaker 1: could probably just go to the other hand and then
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  Speaker 1: back and you get two two values reach one and
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  Speaker 1: you pick the best of each hand. So you pick
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  Speaker 1: the best for your right and the best for your left.
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  Speaker 2: And then you add them up.
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  Speaker 1: So say you were to get ninety kilos from your
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  Speaker 1: left and eighty five for your right hand, you'd add
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  Speaker 1: them up and that's one hundred and seventy five kilos,
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  Speaker 1: and then you divide that by your body weight. Now
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  Speaker 1: again in the United States, if it's measuring it in pounds,
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  Speaker 1: that's fine. You just add up the total pounds in
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  Speaker 1: this case would be about one hundred and eighty hundred
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  Speaker 1: and ninety ish on each hand. You add that up
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  Speaker 1: and then you divide it by your body weight, and
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  Speaker 1: again your bodyweight.
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  Speaker 2: Will be in kilos.
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  Speaker 1: Or if you're doing the American one and they give
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  Speaker 1: you the dynamoma in pounds, then you use your body
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  Speaker 1: weighing pounds.
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  Speaker 2: Now let's get.
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  Speaker 1: Back to the study and what they did was they
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  Speaker 1: tracked deaths all cause mortality, deaths from anything, and death
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  Speaker 1: from cardiovascular disease, and they also assessed cardiovascular disease prevalence
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  Speaker 1: using medical history. They used interviews in national mortality records,
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  Speaker 1: and then they adjusted for all the usual suspects. So
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  Speaker 1: this is important because these were adjusted for things such
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  Speaker 1: as your age, your sex, your body mass index, hypertension, diabetes, smoking,
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  Speaker 1: blood lipids, socioeconomic statius.
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  Speaker 2: They did that lot and.
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  Speaker 1: The results were seriously compelling compared to people. And what
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  Speaker 1: they did is they separated them into quartiles, so the
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  Speaker 1: lowest twenty five percent, then the low medium, the high medium,
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  Speaker 1: and then the highest twenty five percent. Compared to people
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  Speaker 1: in the lowest quartile, so the lowest twenty five percent
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  Speaker 1: of the weakest twenty five percent. Those in the highest
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  Speaker 1: quartile had a seventy three percent lower risk of dying
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  Speaker 1: from any cause in the US cohort and a forty
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  Speaker 1: seven percent lower risk of dying in the Chinese cohort,
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  Speaker 1: and cardiovascular deaths were also dramatically lower in the US cohort.
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  Speaker 1: The strongest twenty five percent had a seventy nine percent
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  Speaker 1: risk reduction for cardiovascular deaths, right, and that is pretty bunkers.
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  Speaker 2: So I'll give you the cutoffs.
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  Speaker 1: Let's just look at the end he hits cohort, So
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  Speaker 1: the lowest quartile.
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  Speaker 2: Q one, when you do then hazard ratios for mortality.
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  Speaker 1: And the Q two so twenty five to fifty percent
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  Speaker 1: in terms of strength, so low the medium. Their hazard
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  Speaker 1: ratio compared to Q one was not zero point four
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  Speaker 1: to seven, so they had a fifty three percent reduced
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  Speaker 1: all cause mortality than weaker So just going from the
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  Speaker 1: weakest to the second weakest group reduced your risk of
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  Speaker 1: all cause mortality by whopping fifty three percent, Like that
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  Speaker 1: is bunkers. And Q three, which are those people sort
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  Speaker 1: of fifty to seventy five percent, so they're above average.
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  Speaker 1: Their hazard ratio was zero point three nine, so basically
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  Speaker 1: they're sixty one percent less likely to die of anything
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  Speaker 1: than the weakest group. And as I said, Q four
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  Speaker 1: their hazard ratio was zero point twenty seven, so they
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  Speaker 1: had a seventy three percent lower risk of all cause
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  Speaker 1: mortality compared to the weakest groups. And that this is
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  Speaker 1: just completely and ulterly bunkers in terms of the impact.
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  Speaker 1: And when we look at the China study, and there
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  Speaker 1: the Q four the strongest group. Their hazard ratio was
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  Speaker 1: zero point five, so they are are forty seven percent
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  Speaker 1: lower risk of death and everything. Why the difference in
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  Speaker 1: the Canadian A sorry, in the Chinese versus the US,
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  Speaker 1: Probably because the US population on the whole are on
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  Speaker 1: the healthier because that they got a higher risk of
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  Speaker 1: dying and therefore and that strength was more protective. But
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  Speaker 1: just taking these things together and this is really impactful
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  Speaker 1: and importantly, the researchers observed a classic L shape relationship,
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  Speaker 1: meaning the biggest benefits come from getting out of the
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  Speaker 1: lowest twenty five percent.
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  Speaker 2: In other words, you don't need.
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  Speaker 1: To be a gym bunny, you just got to be
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  Speaker 1: stronger than the weakest twenty five percent. Personally, I think
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  Speaker 1: this is huge implications for our exercise guidelines. So if
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  Speaker 1: you take the data from Australia, the most recent data
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  Speaker 1: showed that only twenty percent of Australian adults hit the
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  Speaker 1: recommended guidelines for physical activity when it comes to strength training,
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  Speaker 1: particularly in.
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  Speaker 2: Older age groups.
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  Speaker 1: Right, so only one in five are doing the recommended
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  Speaker 1: two strength training sessions a week. About sixty percent actually
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  Speaker 1: hit the baseline of one hundred and fifty minutes of
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  Speaker 1: moderate physical activity a week, you know, so there's reasonable
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  Speaker 1: amount who do that, but only one in five or
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  Speaker 1: twenty percent actually do the strength training stuff. And this
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  Speaker 1: should be a massive, massive wake up call. I mean,
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  Speaker 1: here's the thing. If you have a job that involves
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  Speaker 1: manual labor, you know, your grip strength is probably fine,
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  Speaker 1: in fact, it's probably very good. But if you do
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  Speaker 1: an office job and you're not in the gym lifting
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  Speaker 1: heavy shit, the chances are that you are in one
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  Speaker 1: of those lower two quartiles, and it's more important that
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  Speaker 1: you do strength training. That is really important call to
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  Speaker 1: action here for this, So I'm a big fan. Just
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  Speaker 1: get a basic grip dynamometer online. As I said, it's
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  Speaker 1: going to cost you twenty to thirty bucks depending on
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  Speaker 1: where you are. Measure your grip from each hand, add
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  Speaker 1: them together and then divide that by your body weight. Right,
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  Speaker 1: So again it will give you your grip strength and kilos.
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  Speaker 1: So you divide it in kilos and that is your GSWR.
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  Speaker 2: So I'm having sure my value.
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  Speaker 1: So my right hand was buying on fifty kilos, my
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  Speaker 1: left hand was forty six point nine kilos, so that
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  Speaker 1: gives me a combined force in the two hands of
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  Speaker 1: ninety six point nine kilos divided by my body weight,
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  Speaker 1: which is eighty gives me a GSWR of one point
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  Speaker 1: two to one. So if you're doing any type of
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  Speaker 1: strength training at all, you're likely to be above one
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  Speaker 1: in terms of that cutoff. And in in our house,
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  Speaker 1: everybody is above the cutoff for Q four. So Q
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  Speaker 1: four is not zero point nine two or above right
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  Speaker 1: ninety two percent of your body weight combined hands, you
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  Speaker 1: are in the top quartile and are very very protective. Unfortunately,
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  Speaker 1: the research paper didn't give us all of those cutoffs,
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  Speaker 1: but I went in and looked at it and approximated it.
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  Speaker 2: So they do these curves.
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  Speaker 1: If you read the research paper, you can kind of
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  Speaker 1: work it out from the graphs. So what I've worked
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  Speaker 1: out is is the Q four, which they did say
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  Speaker 1: that was above zero point nine two Q three is
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  Speaker 1: not point eighty eight to not point nine.
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  Speaker 2: Two Q two.
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  Speaker 1: So this is where you're starting to get a little
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  Speaker 1: bit into trouble. That was not point eight three to
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  Speaker 1: not point eighty eight. And in Q one, the weakest group,
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  Speaker 1: we're not point eight three. So if your combined force
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  Speaker 1: from their left in your right hand is less than
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  Speaker 1: zero point eight three. I would suggest that the most
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  Speaker 1: important thing you need to do for your healthy get
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  Speaker 1: yourself into the gym and start lifting heavy shit. Now
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  Speaker 1: that's the data from the En Haynes quote. That's the
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  Speaker 1: American one. I didn't actually do the data for the
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  Speaker 1: Chinese one, but I think that's that's probably good enough
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  Speaker 1: for everybody as a target to go. And this metric
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  Speaker 1: is so powerful and so predictive and so easy to
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  Speaker 1: measure that I think that it should be in every
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  Speaker 1: single doctor surgery and they should do this in routine checkups.
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  Speaker 1: I mean, you come in, they'll do your blood pressure,
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  Speaker 1: some of them do your weight, and let's do your
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  Speaker 1: comparison here, right, So blood pressure, Yes, we know that
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  Speaker 1: elevator blood pressure increases the risk of stroke and heart disease,
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  Speaker 1: but on its own, it's actually quite a poor predictor
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  Speaker 1: of all cause mortality, and it can be quite variable.
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  Speaker 1: Then fasting glucose or even he HbA one C. They
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  Speaker 1: are strong predictors of diabetes risk, but again, many people
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  Speaker 1: live in a gray zone for years, and they're not
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  Speaker 1: actually very strong predictors of all cause mortality, and certainly
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  Speaker 1: not as strong as this script. Strength LDL cholesterol with
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  Speaker 1: many are obsessed with, has been associated with cardiovascular risk,
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  Speaker 1: but half the people who have a heart attack have
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  Speaker 1: normal LDL. And it's a really shit house predictor of
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  Speaker 1: all cause mortality, particularly in older adults and in body
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  Speaker 1: mass index, which you know we've been obsessed with for decades.
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  Speaker 1: Don't even get me started on that shit. It is
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  Speaker 1: such a blunt tool and such a poor predictor of cardiovascars,
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  Speaker 1: the's mortality and all cause mortality. Now, compare that to
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  Speaker 1: grip strength. So we talked about it in this paper,
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  Speaker 1: but I'm going to give you some other evidence, right,
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  Speaker 1: so this is not just a one off. A twenty
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  Speaker 1: eighteen study in a British medical journal found that grip
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  Speaker 1: strength was a better predictor of all cause mortality than
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  Speaker 1: systolic blood pressure. Another study in the Lancet called the
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  Speaker 1: Pure Study showed that grip strength was a strong predictor
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  Speaker 1: of cardiovascular mortality than blood pressure or even physical activity.
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  Speaker 1: So why isn't it standard in every clinic? I guess
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  Speaker 1: that's the question. But strength training is clear that it matters,
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  Speaker 1: and it matters more than we used to think. Now,
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  Speaker 1: if your GSWR isn't where you want it to be.
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  Speaker 1: Don't panic, but you do need to act. And it's
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  Speaker 1: not about just hanging off a bar to improve your
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  Speaker 1: grip strength. Really, grip strength is a proxy for engaging
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  Speaker 1: in strength training. People who have high grip strength either
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  Speaker 1: have done lots of strength training or they do lots
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  Speaker 1: of physical labor, so they're using their muscles. And there
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  Speaker 1: is a mountain of data that supports the idea that
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  Speaker 1: good muscle strength is a really good predictor of not
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  Speaker 1: just how long you're going to live, but also quality
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  Speaker 1: of life as well. I've written extensively about this in
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  Speaker 1: my latest book, The Hardiness Effect, and I've also talked
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  Speaker 1: about it on a couple of different podcasts. But what
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  Speaker 1: we know, for instance, a twenty seventeen study in the
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  Speaker 1: Journals of Gerontology so that muscle strength is a stronger
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  Speaker 1: predictor of longevity than muscle mass. So it's not about
• 15:13
  Speaker 1: big muscles, it's about how strong they are. And then
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  Speaker 1: another meta analysis published in the European Journal of Preventive
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  Speaker 1: Cardiology in twenty twenty two found that people with higher
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  Speaker 1: muscle strength out of thirty one percent lower risk of
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  Speaker 1: all cause mortality compared to those.
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  Speaker 2: With the lowest levels.
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  Speaker 1: Right now, in this study it was it was significantly
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  Speaker 1: bigger than that. But when you see more and more evidence,
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  Speaker 1: are different papers with results that are in a similar direction,
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  Speaker 1: then we start to say, hey, this evidence is really
• 15:46
  Speaker 1: really strong and strength training. The benefits of strength training
• 15:50
  Speaker 1: are more pronounced in older adults. That leads to better
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  Speaker 1: functional mobility, fewer falls, less realty, better glucose control, low inflammation,
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  Speaker 1: and of course better grip strength. So the big take
• 16:05
  Speaker 1: up here is buy a hand grip dynamometer. They are
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  Speaker 1: very cheap, you can get them on Amazon. Measure your
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  Speaker 1: grip strength and calculate your GSWR. Then compare it to
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  Speaker 1: the data that I talked about earlier on If you're
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  Speaker 1: in the lowest quarter earlier that you're even Q two,
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  Speaker 1: commit to change and start strength training twice a week.
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  Speaker 1: We've shown that adults who engage in strength training twice
• 16:29
  Speaker 1: a week significantly improve their strength, particularly older adults. In
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  Speaker 1: a world where we have warribles that track everything and
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  Speaker 1: give us all of these different fancy diagnostics, sometimes the
• 16:40
  Speaker 1: simplest tools are the most powerful. So grab a grip
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  Speaker 1: strength meter, pick up some weights and take control of
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  Speaker 1: a metric that might just save your life or it
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  Speaker 1: certainly will extend it and improve the quality of your life.
• 16:54
  Speaker 1: That's it for this week, folks, Catch you next time.