Over the weekend, my friend Greg Toppo of The74 asked me to comment on Google's new hijacking of—er, I mean new partnership with—ISTE+ASCD, an umbrella ed-tech organization, that willl purportedly train every teacher and higher ed faculty in the US to become "AI ready." Toppo’s comprehensive story is here, and I’m quoted at some length.
But, not enough length! With Toppo’s understanding, I am now share with you the full context of my remarks. I have met the enemy, and it is ISTE+ACSD. See you soon-ish at ASU+GSV, Richard, let’s see if you can look me in the eyes!
It is completely unsurprising, though no less infuriating, that ISTE+ACSD continues to double-down on its leading role as shill for Big Tech.1 I’m sure it’s nice to unlock Google’s funding, but what so profit an allegedly nonprofit education organization if it shall loseth its soul? All the while doing damage to teacher effectiveness and student learning in the process.
But that of course presumes there’s any soul at ISTE that’s left to be lost, which seems unlikely. Richard Culatta, who worked in the Obama Administration and is someone I once respected, seems blissfully unaware that ‘AI literacy’—a stupid and largely incoherent term, but surely one that if it has any meaning suggests a modicum of critical thinking—might result in teachers resisting these tools of cognitive automation. To be sure, ISTE says resistance is futile, because “the future” will demand “AI readiness.” I’d credit their clairvoyance just a tad more if ISTE had not claimed, as recently as just a few years ago, that “the future” would also demand that everyone learn to code.2
Oops!
If we can bracket the odiousness of ISTE’s grift, I admit I’m fascinated to see the major Big Tech companies competing so vigorously to control “the education market.” OpenAI is giving away their premium model to teachers (until they won’t), and now Google is doing whatever this is.3 Of course, Google is also the company that once ran ads suggesting children should use AI to outsource the drafting of their letters to their heroes, so I confess I’m just a tad skeptical of their commitment to “student agency” and “critical thinking” nowadays. As a company, they’ve tried to erode the former, and shown little collective capacity for the latter.4
I also must briefly note the contradictory, and fundamentally very stupid, paradox sitting at the center of the AI hype right now. On the one hand, we are told AI models are on the the verge of ravaging the entire global economy and will soon destroy the need for knowledge work of any sort. That’s bullshit of course, but if it were true, then why in the world would teachers need any training to understand how to “use AI responsibly”? For that matter, why would we even need teachers at all, if AI will obviate the need for any human thought expended toward any productive enterprise? The robots will do all our work for us, as we become robots ourselves.5
The good news is that all of this will end up being a waste of teachers’ time and Google’s money and ISTE’s relevance. That’s my prediction about “the future,” and I’m confident in it because I know a thing or two about the science of learning. Human beings have evolved to learn from each other in the context of our relationships. This is the superpower of our species, and the kids who’ve grown up in the past 20 years are increasingly disgusted by what tech has done to them personally, and society more broadly. They are not happy about the world we’ve given them, and their voices are growing ever louder. There’s no hope that Google or ISTE will listen to them, of course.
I stand second to no one in my anti-Anthropic sentiments, but even I can admit their recent ads digging at OpenAI’s plans to incorporate “advertising” into its model were funny as hell. Can’t wait for teachers to prompt “tailor this lesson to a student’s audio learning style” and then receive output that was bought and paid for by some corporate grifter. ISTE, maybe.
For the record, even if we assume for the sake of stupid argument that AI robots or whatever will do everything for us in the future, we would of course still need teachers, because our human lives are enhanced dramatically by education, it is an end unto itself, not a f’ing jobs-training program.
In the past couple of weeks I’ve had 2 patients contact me because they were worried: their V02 max was decreasing. Their data were based on smartwatch imputations, which are notoriously imprecise. But the problem is much bigger than that. In this edition of Ground Truths I’m going to get into the difference between cardiorespiratory fitness and V02 max, which are remarkably different for the way they are measured, the datasets that assess them for functional significance and outcomes for healthy adults, and how we got into this craze.
A schematic I made with NanoBanana Pro (the use of a treadmill or bicycle is interchangeable but the measurements are altogether different .
How They Are Measured
Cardiorespiratory fitness (CRF) is a real world assessment of a person activities, such as walking or on a treadmill, a reflection of a person’s resting metabolic rate, measured in metabolic equivalent of task (MET) units with 3 recognized levels of intensity : Light (<3.0 METs), example slow walking; Moderate (3.0-5.9 METs), example brisk walking, 3-4 miles per hour; and vigorous intensity (>6.0 METs), example jogging. 1 MET is the energy used in sitting or resting; 10 METs requires 10-fold the energy expenditure. CRF integrates cardiovascular, lung and musculoskeletal functional capacity.
There are multiple methods to calculate your METS, including a standard treadmill MET chart (below left) that plots speed and incline, use a formula if you are doing the Bruce treadmill protocol or the chart below (right), or using heart rate (with any aerobic activity, such as bicycling or jogging) with the formula: METS=0.05 X heart rate+2. So if your HR got to 140 that would be 9 METS. For every increase in heart rate of 10 beats per minute, there’s about a 1 MET increase.
Maximal oxygen uptake (V02 max) is only accurately determined as a performance lab test with a metabolic cart, trained technicians, a specialized tightly fit mask that captures every molecule of inhaled oxygen and exhaled C02 on a ramped treadmill or stationary bike exercise protocol until absolute exhaustion. This is the ceiling of aerobic power achieved via direct gas exchange. A V02 max test costs about $150 for a standard assessment in a university lab.
V02 max by wearables are obviously not measured by gas exchange or directly, but instead through various imputations based upon population-based algorithms of heart rate and movement (GPS/accelerometry). Studies have assessed the Apple Watch, Garmin Fenix 6, and Fitbit with a mean absolute percentage error of 7-16%. Overall, they have been found to consistently underestimate V02 in fit people while overestimate in unfit individuals. They also rely on optical heart rate (which may be inaccurate in people of color), device positioning and wrist anatomy, and can be influenced by such factors as hydration status, altitude, and ambient temperature. Typically, a 6-minute walk is the basis for a wearable to provide the user a new V02 max result. That may not be at all representative of an individual’s exercise capacity.
In JAMA 2009, a meta-analysis of 33 studies of cardiorespiratory fitness was published for the relationship to all-cause mortality in a total of 102,980 participants. A better CRF (per 1 MET higher) was linked with a lower all-cause mortality (Figure) and individuals who had achieved 7.9 METs had substantially less all-cause and cardiovascular mortality. One MET higher CRF was associated with a 14-15% reduction of mortality.
In 2016, the American Heart Association issued a scientific statement on CRF and asserted it should be regarded as a clinical vital sign, reviewing all of the published data to that point.
Here is the Table of METS performance by age and sex. You can see there are 5 categories (columns) from low to elite.
All-cause mortality by sex and the 5 levels of performance are plotted below. The hazard ratio of 1.41 (about 40% increases risk of all-cause mortality) for above average vs below average was the same as the risk of smoking or diabetes. The hazard ratio for mortality from low to elite was more than 5-fold. The favorable impact for women beyond men for METS was seen for each performance group. These results were adjusted for potential confounding variables.
Here is a good summary graph of that study. In both there was no risk of increased mortality at the highest fitness strata—in fact it was consistently lower for each age group.
Datasets for V02 Max
There are limited data for direct measurement of V02 max and outcomes. The 2001 Kuopio study from Finland of 1,294 men with 10.7 year follow-up did measure V02 max directly once at baseline along with a symptom-limited exercise tolerance test on a bicycle ergometer. The relationship of V02 max (by quartiles) to all-cause mortality is shown below.
In a 2024 meta-analysis of 42 studies with V02 max (as categorized as “objectively measured CRF”) and estimated CRF for prediction or all-cause and cardiovascular mortality, the results were remarkably similar (cardiovascular mortality, 14% reduction, graph below) but notably there were 234-fold more participants with exercise CRF than by V02 max measurements, or >99% of the data is derived from METS. That is to say, nearly all the data we have for link to outcomes comes from CRF, not V02 max.
Reference standards have been published by age group for V02 max. For more information such as by sex, please check the link.
The leading proponent of using V02 max in recent years has been Peter Attia, through his podcast The Drive and book Outlive. He has consistently asserted “V02 max is the singular most powerful marker for longevity.” But the problem is conflation. He cites all of the studies of CRF without measuring V02 max and extrapolates to a V02 max result (see side-by-side Kokkinos study Table and Outlive Figure footnote below) and throughout his discussion of exercise in Chapter 11 of Outlive. For example, he writes: “this number [V02max] turns out to be highly correlated with longevity” citing all studies that did not measure V02 max.
In a recent YouTube video by Joseph Everett and Nick Norwitz entitled “Hidden Data: How the Top Longevity Doctor Tricked Us All” there is a segment about V02 max and this significant issue of conflation, discussed by Chris Masterjohn. Below is the relevant 6 minute clip within the longer video. It includes a bit of the 60 Minutes segment with CBS correspondent Nora O’Donnell doing a V02 max text and Peter’s assertion: “We don’t have a single metric of humans that we can measure that better predicts how long they will live than how high their V02 max is.”
As Masterjohn aptly points out, the fixation on V02 max, which is not actually supported by the data, also misses out on our ideal goal of diversity of exercise, including strength and balance training. Indeed, Kim et al, analyzing over 70,000 UK Biobank participants, for both CRF (submaximal bicycle test) and grip strength with all-cause mortality and concluded: “Improving both CRF and muscle strength, as opposed to either of the two alone, may be the most effective behavioral strategy to reduce all-cause and cardiovascular mortality risk.”
Bottom Line
I’ve never done a V02 max and see no reason to do it with the issues of cost, inconvenience, and the pain. As Attia correctly states about going to maximal exhaustion to get V02 max: “If you’ve ever had this test done, you will know just how unpleasant it is.” For spartan, Olympic, high performance athletes who are in high intensity training, or in patients with heart failure or pulmonary hypertension there may be a place for serial V02 max measurements, providing highly objective “goal standard” physiologic metrics. Otherwise, there are no supportive data for people going out and getting a V02 max and making this the focus of their exercise training. That is the reason I didn’t even mention V02 max in my Super Agers book.
Nearly all of the relevant data related to outcomes are based on exercise on a treadmill or bicycle with METS as the index of cardiorespiratory fitness. We should not be placing much value on our smartwatch data. My Apple Watch gave me encouraging high V02 max data over 6 months to suggest my CRF is well above people in my age group (70+, see reference standards above) but I know the data is woefully unreliable.
The problem now, with so much misplaced hype on V02 max, is that most people are using their smartwatch output for gauging their cardiorespiratory fitness, like the 2 patients I mentioned at the top of the post. It’s free to calculate your METS! And that is the real basis of the relationship to all-cause and cardiovascular mortality that has been firmly established in the peer review literature.
This problem surfaced recently with the introduction of ChatGPT Health. Geoffrey Fowler, the tech journalist at the Washington Post, submitted all his Apple Health and asked for an overall assessment of his health (actual prompt: “give me a single score (A-F) for my cardiovascular health over the last decade including component scores and an overall evaluation of my longevity.”) It gave him an “F.”
Then he gave ChatGPT Health his electric medical record access (portal) and asked the same question again. It gave him a “D’ and attributed that to his V02 max data of 34 ml/kg/min in the past year, below a 45-50 year old male! He also entered his Apple Watch data to Claude Health and it gave him a D+ status Specifically, Claude Health gave him a C- because his V02 max had declined from 41 to 32 ml/kg/min from 2016-2026. But the had over 7,500 step/day throughout the decade.
These outputs are indicative of the problem—the unreliable wearable V02 max data have become unduly emphasized by current AI platforms using smartwatch data! That will only make the problem worse, adding to the confusion, conflation, and emphasis on the wrong metric.
I hope this post helps to sort out what we know and that the datasets for cardiorespiratory fitness, representing real world physical activity— not V02 max —are the basis of the link to improved survival and freedom from cardiovascular mortality.
If we’re going to focus on a metric it ought to be METS, not V02 max. Not only is it free, simple and universally available, but it is the one best studied for health outcomes. And perhaps the better strategy is to be as physically active as possible and not worry about any metric!
NB: No AI was used in any way to write this post. As mentioned in the caption, I got help from Gemini-3 to produce the first Figure. I have nothing to do, no COI, with any company working with cardiopulmonary fitness or V02 max.
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The first fiber-optic cable ever laid across an ocean -- TAT-8, a nearly 6,000-kilometer line between the United States, United Kingdom, and France that carried its first traffic on December 14, 1988 -- is now being pulled off the Atlantic seabed after more than two decades of sitting dormant, bound for recycling in South Africa.
Subsea Environmental Services, one of only three companies in the world whose entire business is cable recovery and recycling, began the operation last year using its new diesel-electric vessel, the MV Maasvliet, and had already brought 1,012 kilometers of the cable to the Portuguese port of Leixoes by August.
TAT-8, short for Trans-Atlantic Telephone 8, was built by AT&T, British Telecom, and France Telecom, and hit full capacity within just 18 months of going live. A fault too expensive to repair took it out of service in 2002. The recovered cable is being shipped to Mertech Marine in South Africa, where it will be broken down into steel, copper, and two types of polyethylene -- all commercially valuable, especially the high-quality copper at a time when the International Energy Agency projects global shortages within a decade.
Have you ever wondered why you don’t have to spit out seeds after snacking on a banana? It’s because the Cavendish, the most widely used commercial cultivar, has three copies of chromosomes and can’t produce fertile seeds. Instead, the Cavendish is propagated by cloning, which is convenient for maintaining consistent banana quality, but leaves the plant vulnerable to disease.
It’s a fate that befell the Cavendish’s predecessor, the Gros Michel (French for “Big Mike”). This more flavorful cultivar was the most widely available banana for decades until it fell victim to the wilting fungus Fusarium, known by the colloquial name “Panama disease.” By the 1950s, Gros Michel bananas had all but disappeared, and the Cavendish became the dominant cultivar, accounting for 99 percent of banana exports today.
For years, the Cavendish was thought to be resistant to the soil-borne Panama disease, until the 2010s when a virulent strain of the fungus, Tropical Race 4, started spreading. With bananas under threat worldwide, the race to protect the Cavendish from suffering the Gros Michel’s fate began. Now, agricultural scientists are making headway with new research published in Horticulture Research.
Andrew Chen and Elizabeth Aitken from the University of Queensland recently pinpointed the location of a gene in the wild banana plant—Calcutta 4—that confers resistance to Fusarium wilt, Sub Tropical Race 4 (STR4).
“We’ve located the source of STR4 resistance in Calcutta 4 which is a highly fertile wild diploid banana by crossing it with susceptible bananas from a different subspecies of the diploid banana group,” Chen explained in a statement. “This is a very significant finding; it is the first genetic dissection of Race 4 resistance from this wild subspecies.”
Because the banana plant crosses had to grow for a year before they could be checked for disease-resistance, locating the gene took five years. You may be wondering why we can’t just make the switch from the Cavendish to Calcutta 4 the way we swapped the Cavendish for the Gros Michel.
“While Calcutta 4 provides crucial genetic resistance, it isn’t suitable as a commercial cultivar because it doesn’t produce fruit which are good to eat,” Chen said.
Going forward, the researchers are developing molecular markers for the gene so banana producers can more efficiently identify and plant resistant seedlings. “This will speed up selection, reduce costs and hopefully ultimately lead to a banana that is good to eat, easy to farm, and naturally protected from Fusarium wilt through its genetics,” Chen said.
As you progress in your UI design career, you learn that there are quite a few unsolvable challenges:
do you write My Items or Your Items in UI?
do you put hand cursors over buttons?
for a boolean item (especially in the menu), do you talk about the present state or the future state?
do you try to solve for change blindness or change aversion?
I was reminded of one of those today: how do you sort the items in the bottom-aligned menu?
One school of thought is to keep it in the same order as you would a regular top-aligned menu:
On the positive side, this allows to build consistent understanding of how menus are structured: the most important thing is at the top, Quit is always at the bottom. But the downsides are obvious, too – now the most important item is furthest away from where you cursor started, and you have to awkwardly cross all the other items on the way to it.
iOS’s springboard went, literally, the other way:
Here, the bottom aligned menu reverses its item order. This tripped me up today. The dock in macOS was actually more defensible upside down because there, every menu was always going the same way. Here, the inconsistency starts rearing its ugly head.
Of course, the best way to not face an impossible choice is to avoid it altogether. Not sure how one could accomplish it here, though. Placing the menus consistently below would make some of them scrollable, or basically invisible for bottommost icons. You could also slide the entire screen up to make room for the menu, but that would probably feel disorienting.
So, I can’t say this is a wrong solution. The inconsistency might only bother people who use this often, and maybe no one uses this often? Or, perhaps, it was really important to allow to resize widgets and make that item as easy to tap as possible? But still, I think I would have done it the other way – align as needed, but items always in the same order.
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