19 subjects, assigned sedentary or active based on habitual physical activity levels. Subjects were screened on basic health measures.
The problem with this is that people are sedentary or active for a variety of health-related reasons that are not captured in any screen (esp. the crude one used in this study). As a predictive study, this is fine, sedentarism predicts a lot of bad things. But it doesn't, on its own, suggest that becoming active is helpful. See also grip strength and mortality.
The principle of what you're stating is true, it could be correlational.
But there's an enormous volume of evidence that exercise, especially intense exercise, is better for health than any other intervention, including more sleep, quality of diet, pills+supplements (except those that treat an active illness/disease of course).
There's even compelling data showing that moderate drinkers who exercise live longer than non-drinkers who don't exercise. Even given that Alcohol is a powerful carcinogen.
The only thing proven more effective than exercise is weight loss really, if starting from high bodyfat levels.
(Anything above ~15% bodyfat in men has negative implications for lifespan, and ~30% for women; when reviewed at scale)
That sounds like a study that is pretty tough to control for, especially long term and at scale.
You'd need to find subjects that are provably capable of sustaining intense exercise as a habit if they wanted to but never did, and won't either for the years you'll be following them.
That won't work in the reverse, as people can be consciously or not self adjusting based on the health conditions you're trying to check.
PS: I'm remembering a friend who never liked running, but tried pretty hard after being pestered by their doctor and family, to discover that their knees are just not good and their whole lineage hated running for a reason. Intense exercise can be anything else, but people won't know their real health limitations until they actually do it for a while.
That intense exercise is good, and even very good for you, is proven as far as reasonably possible given that we can't run deterministically controlled experiments.
More evidence may come out that adds nuance, but the effect size is so large that it becomes obvious in the data just from observation.
You can cycle or stationary bike if you have bad knees. There are plenty of exercises that are intense but easy on the joints.
I'd love to find out if electrical muscle stimulation while sleeping could effectively provide exercise without causing excessive sleep disruption. Could be a zero-effort supplemental form of exercise for sedentary people.
> mitochondria, which process energy within cells, showed a significantly decreased capacity to burn both sugar and fat in healthy individuals who get less than the recommended 150 minutes of exercise a week.
150 minutes a week is about than 22 minutes a day. Like 11 minutes twice a day. This looks like a really low effort to rid oneself of the risk of early decline.
I've seen studies like this before. They'll suggest that as little as 15 minutes of exercise significantly improves health in some group they studied. My initial assumption was they added 15 minutes of additional exercise. No, they studied people who did literally nothing. Then had them exercise 15 minutes a day.
As you might guess, their outcomes improved greatly.
The amount of time in the exercise advice keep getting shorter and shorter. The common advice when I was younger, in the USA, was an hour of exercise. Couldn't get enough people to do it. Then it was 30 minutes. Still couldn't get people to do it. Now the advice has been 15 minutes a day for a while, and we'll still not be able to get people to do it.
The environment and culture needs to be structured such that people get the exercise they need "naturally". The vast majority aren't going to go out of their way for it.
This is sadly not a rare type of person. I'm worried my parents fit this description, they drive everywhere and work an office job. I'd guess on average they get 0 minutes of exercise a day.
I think people get this image in their head that someone who doesn't exercise ever is this comically fat unemployed person when in reality it's the average office worker who isn't fitness minded. A good chunk of HN users wouldn't be getting 15 minutes of exercise a day.
A lot of people who use a car to get around will spend most days doing literally no actual exercise. For someone who lives in a more walkable area, 22 minutes of exercise is just living live normally without actively "exercising".
A studied showed that elderly asians have better health outcomes that their western counterparts in part due to their practice of sitting on the floor. The added exertion of standing up from the floor rather than a chair makes a material difference in their health.
Some of the health tests in Japan that elderly people take include a "standing to sitting on the floor and getting back up all unsupported" test. Scores are based on time, effort, emitted sounds (like grunts), hands-on-ground and whatnot. I don't know the specifics, but it is used as a "health measure."
I remember reading somewhere that one of many long life markers is if you can go from sitting on your butt straight into standing without your hands or knees touching the floor.
I was busy building a sensorless maintenance calorie tracker.
Sometime back i posted this on HN: https://news.ycombinator.com/item?id=48614890
It also has "sedentary" detection which i find pretty useful for the phases when my activity level drops, reduced activity directly reflects in your maintenance calories which maybe useful to some.
It would be cool if one could safely adapt to modern life (lots of sitting, required focus over long sessions) without having to spend time exercising if they don't want to (to be clear, some people want to). Imagine if you could just take something to get all the benefits of exercise, without having to actually spend the time. That'd be pretty great for everyone if it truly was safe and without downsides (skeptical).
They make stationary bikes that fit under a desk. I've never used or seen one, but they exist. I considered getting one during 2020, but they seemed impossible to source.
What if we could just lay in a pod 24/7 taking peptides and nutrient supplements while having an endless stream of instagram reals beamed in to our eyeballs on our Meta Raybans. That way we would never have to do pesky things like go outside or move.
On the other hand, a pill to replace all the un-fun activity needed to stay in shape while having a family and office job would let you enjoy fun activity a lot more, and want to do those things more often, since they’re all more-fun and safer if you’re already in shape.
The problem with this is that people are sedentary or active for a variety of health-related reasons that are not captured in any screen (esp. the crude one used in this study). As a predictive study, this is fine, sedentarism predicts a lot of bad things. But it doesn't, on its own, suggest that becoming active is helpful. See also grip strength and mortality.
But there's an enormous volume of evidence that exercise, especially intense exercise, is better for health than any other intervention, including more sleep, quality of diet, pills+supplements (except those that treat an active illness/disease of course).
There's even compelling data showing that moderate drinkers who exercise live longer than non-drinkers who don't exercise. Even given that Alcohol is a powerful carcinogen.
The only thing proven more effective than exercise is weight loss really, if starting from high bodyfat levels.
(Anything above ~15% bodyfat in men has negative implications for lifespan, and ~30% for women; when reviewed at scale)
That sounds like a study that is pretty tough to control for, especially long term and at scale.
You'd need to find subjects that are provably capable of sustaining intense exercise as a habit if they wanted to but never did, and won't either for the years you'll be following them.
That won't work in the reverse, as people can be consciously or not self adjusting based on the health conditions you're trying to check.
PS: I'm remembering a friend who never liked running, but tried pretty hard after being pestered by their doctor and family, to discover that their knees are just not good and their whole lineage hated running for a reason. Intense exercise can be anything else, but people won't know their real health limitations until they actually do it for a while.
That intense exercise is good, and even very good for you, is proven as far as reasonably possible given that we can't run deterministically controlled experiments.
More evidence may come out that adds nuance, but the effect size is so large that it becomes obvious in the data just from observation.
You can cycle or stationary bike if you have bad knees. There are plenty of exercises that are intense but easy on the joints.
Looking around, the simplest wording I get:
> the intensity must be high. This means that you need to really exert yourself so you get out of breath. [https://norwegianscitechnews.com/2026/05/exercise-a-very-lit...]
So if climbing the stairs gets someone out of breath it's intense (and I also see how getting to your limits, whatever they are, can help)
More and more studies have been indicating that even just a few minutes of intense exercise can outperform long/slow LISS type cardios.
E.g. 5m all out effort is probably better, or at least equivalent, for health as a 30m moderate effort.
The average person can likely hit the 80/20 benefit threshold at less than 30m/week.
Can you link evidence for this? I stay at 12% year around as male (confirmed via DEXA)
https://www.acpjournals.org/doi/pdf/10.7326/M15-1181
Though to be clear, there aren't a ton of studies that look at bodyfat percentage. Most use BMI and similar measures.
Likely overall fat levels matter more than %, I'd guess.
E.g. I'd presume being 15% at very muscular levels is less healthy than 15% at moderate.
(Because absolute fat mass plus visceral fat would be higher)
150 minutes a week is about than 22 minutes a day. Like 11 minutes twice a day. This looks like a really low effort to rid oneself of the risk of early decline.
As you might guess, their outcomes improved greatly.
The environment and culture needs to be structured such that people get the exercise they need "naturally". The vast majority aren't going to go out of their way for it.
I think people get this image in their head that someone who doesn't exercise ever is this comically fat unemployed person when in reality it's the average office worker who isn't fitness minded. A good chunk of HN users wouldn't be getting 15 minutes of exercise a day.
https://duckduckgo.com/?q=desk+stationary+bike
That's better than what i'm doing, hunched over my desk with the metabolic rate of a sleeping lemur, but...it's a slow stroll.