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High air pollution could diminish exercise benefits by half – study

188 points by ashishgupta2209 11mo ago

bluesky19283746 11mo ago
It sounds terrible . What will happend in the future?! The research doesn't differentiate between seasons , and every one knows how polluted the air is in the winter when everyone is heating their home and apartament.
- colinb 11mo ago
  One more reason to look to an electrically heated future. Where I live the air becomes unpleasant in winter as some neighbours heat their homes by burning what i can only assume are old tires and horse carcasses.
  - tgsovlerkhgsel 11mo ago
    I remember as a kid visiting the home of a relative who had an old oven for wood/coal heating, even though the primary heating was now a gas (natural gas not gasoline) heater. The old oven remained though, and was used as a self-emptying trash can. When it filled up, a fire was lit to empty it. I don't remember what the sorting rules were (I assume "does it burn well and not smell up the apartment too badly when lighting it") and how common plastic packaging was back then, but I'm sure that the emissions coming out from the chimney were not a concern.
  - lm28469 11mo ago
    Burning clean dry wood in a modern well maintained wood stove is surprisingly efficient and relatively clean (+ renewable) Of course if you burn trash none of that matters, but it's already illegal in pretty much any advanced societies.
    - colinb 11mo ago
      oh, it's illegal where I live. But some people pretty clearly ignore that. Enforcement doesn't seem to be a thing. I think this is one of those laws that falls into the category of things that we just have to rely on people's good will to carry out. Like small-time littering and not cleaning up after your dog, some people just don't seem to care. FWIW, I think - based on not feeling my throat close up most of the time - that the number of people who do this is small.
- adrianN 11mo ago
  In the future electric cars and heat pumps will improve the situation.
  - edhelas 11mo ago
    And how the electricity will be made? Without any CO2 for sure! (or not... yet)
    - rafaelmn 11mo ago
      What does CO2 emissions of electric power plants have with air quality in cities ?
    - cinntaile 11mo ago
      Power plants are usually not placed inside cities. Less gasoline cars inside cities will definitely improve the local situation, not just limited to CO2.
    - cowsandmilk 11mo ago
      CO2 isn’t particulate matter. But more importantly, larger percentages of our electricity is being made without burning things.
    - hagbard_c 11mo ago
      Nuclear power is a good option, wind and solar are usable for charging batteries - either EV batteries or storage banks which can be used to charge EV batteries. The problem with wind and solar is that there is no long-term storage solution as of yet but single-day storage is already achievable. Once enough nuclear capacity has been built up I foresee wind turbines disappearing from the landscape since they are cumbersome bird-killing eyesores. Solar power is there to stay since buildings need roofing anyway and we'll soon be at a point where the price difference between 'passive' roof cladding and PV 'panels' is close to negligible so it makes sense to install PV roof cladding and get some power for free, especially in places where air conditioning is popular.
  - ozim 11mo ago
    You still have break pads and tires particles floating around.
emacsahmed 11mo ago
[dead]
clumsysmurf 11mo ago
I look at the PM2.5 data for my city every day, and at this point (Nov) in the winter season, the only acceptable time to exercise is between 2PM-4PM after vertical mixing kicked in. Outside that duration, particulates are elevated after morning rush our, after evening rush hour, or during overnight inversion trapping evening rush hour + wood burning smoke until the next morning rush hour. This is one the main reasons why I would prefer working remote, it is hard to utilize this time well (for exercise) if you are in the office. At least with PM you can wear a mask, although I am still searching for the best one that works during intense exercise. Also wanted to point out "Trump EPA moves to abandon rule that sets tough standards for deadly soot pollution" https://apnews.com/article/epa-soot-air-pollution-trump-zeldin-deregulation-d7df5b24a159284e96b12958a840c3d8 https://apnews.com/article/epa-soot-air-pollution-trump-zeld...
- krzat 11mo ago
  > I am still searching for the best one that works during intense exercis Try a professional mask, like 3M 7500 with 2138 filters.
  - clumsysmurf 11mo ago
    Thanks, that's one of the masks I use! Unlike the GVS SPM587 it has a quick release thing so you can get to your hydration for water and microplastics :/
Theodores 11mo ago
If only you could see it. In the big cities the air quality has improved, however, I am not sure if it really has, or if we are now just burning hydrocarbons more efficiently so that the particle sizes have become invisible. Put it this way, although cars are allegedly better than they were, fuel consumption hasn't dropped considerably. The cars are more numerous than ever, and, although there are EVs, there are still more ICE cars than there were in the good old days when petrol came with lead in it. I am not sure that most people in urban areas even know what good air tastes and smells like. I take a canal path through lush countryside, far from any cars for most of the way. This canal has an aqueduct (or is it a viaduct?) over a motorway and the contrast is incredible. You go from basically smelling flowers to air pollution and back to clean air again quite quickly, so the filth is totally noticeable. Note the cars on the motorway are going at speed, so they should be working efficiently (until a few decades ago 56 mph was what engines were optimised for regarding efficiency in the UK). If just living in a major city then you don't get this instant switch from bad to good air. So you just don't notice it. If you could see the filth, you would prefer a swimming pool that was pissed in, it is that toxic. If you do have to live in a city, my top tip is to find out if there are any meteorologists in town. If there are, buy a house next to where they are living. Anecdotal, however, I used to work with meteorologists and they would always live to the West of the city centre, to get cleaner air than those living in the east of the city, or further downwind. Again anecdotal, however, due to the canal and motorway experience described above, in post-industrial countries such as the UK, it is definitely the vehicles rather than any other source. Given the choice of microparticles that just get in your blood or clumps of big particles that you can eventually cough up and spit out, I would much prefer the latter. My hunch is that the legislation to improve vehicle emissions has optimised the exhaust for nanoparticles. Please prove me wrong!
- softwaredoug 11mo ago
  For urban areas the risk of air pollution is another reason for cities to have congestion pricing to support public transportation.
- jwr 11mo ago
  > I am not sure that most people in urban areas even know what good air tastes and smells like. I run air filters in my apartment throughout winter months, which tend to be the worst in terms of air quality here. When I go outside in the morning I can really smell the stuff in the air, for a brief moment, until I get used to it. But you definitely notice the difference!
softwaredoug 11mo ago
Before people freak out about their morning run, I’m very hard pressed to find 25 PM2.5 on this map of the US. (Note these numbers are AQI, you have to zoom into the bad AQI numbers and look at their PM2.5). Albeit it’s a Saturday morning, not rush hour. China and India look rough though. https://www.iqair.com/us/air-quality-map https://www.iqair.com/us/air-quality-map
- thearrow 11mo ago
  Please note that air quality in an area varies dramatically over time. You are looking at a current snapshot with maps like that. The map linked below has his more historical data and I can see several _weeks_ this past year in my area (which currently has very good air quality) where the PM 2.5 weekly average exceeded 25ug/m^3. https://map.purpleair.com/air-quality-raw-pm25 https://map.purpleair.com/air-quality-raw-pm25 Localized phenomena like a neighbor starting a fire, up to the activity of nearby factories and power plants, up to national and global phenomena like wildfires and weather patterns, all have dramatic effects. Looking at an air quality map once and determining that you don’t have to think about air quality because you’re in the US is a mistake. Exercise outdoors is a wonderful thing, obviously, but there are some days, even in the US, where you might think twice or even consider shifting your exercise to a different (less-polluted) time of the day.
  - metadope 11mo ago
    > Localized phenomena like a neighbor starting a fire, Summer evenings at home in my small Ohio village are often a health hazard, a polluted nightmare driven by the perverse compulsive ignition of so-called 'recreational' yard fires by pyromaniac neighbors. If it is an Ozone Action day and/or a Heat Advisory day, it is near certain that one or more of the Don't Tread On Me jamokes who live nearby will come out of their houses at sunset, pile a bunch of garbage into a 55-gallon drum or a circle of rocks, sprinkle with accelerant, toss a match and back away. Eyes glazed, they'll watch for a minute, then go back inside, sometimes coming back out every ten minutes or so to refuel the fire, other times letting it blaze until the original pile is down to embers. In any case, there is a new plume of local smoke to add to the day's irritants. It is a startling phenom to observe, let alone endure. The behavior is made all the more crazy, imho, by the presence of children. These are parents, asserting their rights to burn, and teaching their children to Live Free Or Die. It seems to me to be driven by a rebelliousness, part of the anti-woke wave, country-fried counter-culture, as in "I got your global warming right here, pard". It's like, listening to country music stations and realizing how many (most!) contemporary and historical Country songs are themed around alcohol-worship. But I digress. I apologise. I was triggered by the mention of 'localized phenomena' and the horrified realization that so many of my fellow citizens are self-destructive cray-cray.
kqr 11mo ago
I want to pull two quotes from the article. > “Our findings emphasise that exercise remains beneficial even in polluted environments,” lead researcher Professor Po-Wen Ku said in a statement. [...] “We don’t want to discourage people from exercising outdoors,” said Co-author Professor Paola Zaninotto. The health effects of exercise outdoors are combined from two effects: - Positive effects due to exercise. These start out strong but level off after a while. - Negative effects due to pollution. These increase almost linearly with time spent outside. One might ask, is there an amount of daily exercise at which the negative effects overpower the positive ones? Yes, in a handful of cities around the world, after a few hours of exercise, the pollution makes additional outdoors exercise actually harmful. But almost everywhere a marginal minute of exercise provides a positive effect on health regardless of time already spent exercising, and there is nowhere in the world where something like an hour of exercise a day is a net negative. Get out there. Pick an active means of commuting (cycling, running, walking, skiing, rollerblading, skateboarding, unicycling) and don't worry so much about pollution unless you live in one of those single-digit cities which I forget where they are, but probably concentrated in Asia. (I feel bad about typing this out without linking to the source. I'm looking for it in my notes!)
- ta12653421 11mo ago
  I remember an interview with the producthead of Google Earth (the desktop client), she said when photographing all the streets, the cars also checked for air pollution: She mentioned a capital in Europe, where the amount of particles under certain sizes differed by 10x from one crossing to the next.
  - potato3732842 11mo ago
    The measurement may very well be accurate but statements like that should set off massive red flags and not be taken at face value. A factor of ten difference for something that just kinda diffuses through the air doesn't "just exist". You don't get gradients like that "naturally" for the most part. It's the result of something. Maybe there's a source something is upwind of and something else is downwind of. Maybe there's conditions causing it to concentrate. Or it varies 10x day to day, but on an average basis it equals out. Etc. Etc.
qprofyeh 11mo ago
If you have ever been to a city that has banned fossil fuels then you can absolutely tell the difference, to most of the overpopulated European cities that I have visited. It’s astonishing how peaceful and comfortable it is to run or even stroll when every breath is just 100% refreshing; you feel 10 pounds lighter. Meanwhile the blackened filter of our home HVAC needs replacement again… and allergies.
- unglaublich 11mo ago
  Sadly, fossil fuel (pollution) has been marketed as a masculine culture thing now. In the free (=individualistic) West, I expect it to stick around for at least another 50 years.
  - labcomputer 11mo ago
    I expect less than 10. Once you drive an EV, every big noisy diesel feels impotent and gutless. Kind of like a small yappy dog that’s all bark and no bite. There’s just nothing like the zero-lag gut-punching acceleration of an EV.
    - array_key_first 11mo ago
      Unfortunately it's not really up to us plebs, it's up to the rich and powerful, who have every incentive in the world to continue fossil fuel use. Trump has outright said he's pro fossil fuels and his policy choice shows it. If there was a proposal to ban or limit EVs in the US, I would not at all be surprised. These people do not care about you or me or all, just their pocket linings.
    - yosito 11mo ago
      Like many other "masculine culture" things, the propaganda sold to men about what's masculine doesn't necessarily have a connection to reality.
    - Timon3 11mo ago
      The industry is trying their best to fight against it. The EU is currently planning to ban new ICE cars from 2035, but the conservative German government & car lobbyists are trying to get them to drop those plans... That, combined with high tariffs for cheap asian EVs will probably artificially keep us on ICEs for a while longer.
unglaublich 11mo ago
And all the while, nothing is done to get old 2-stroke mopeds of the road in Europe. It’s such a low hanging fruit to get those hyper polluters out of cities but in an individualistic society, personal cult status seems more important than common health.
- dylan604 11mo ago
  These seemed like the obvious EV conversion target to me before cars for Europe. Why have these not been converted to EV?
  - unglaublich 11mo ago
    They have, but individuals value nostalgia more than practicality.
  - seec 11mo ago
    The problem is that they are not cost competitive at the time of sales and the type of people who buy those are not exactly the smartest when it comes to total cost of ownership calculation. Over time an electric version would be much cheaper (a few hundred kilometers depending on electricity price) but it's also not as convenient/capable/performant so it's a not exactly an easy sell to the target customer. I do agree that they are highly annoying but the reality is that they are still in use because there is no real equivalency in the electric world.
- deleted 11mo ago
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potato3732842 11mo ago
Cities have mostly only gotten cleaner with time. This is way, way, way down the list of things that I'm worried about killing me.
metalman 11mo ago
air pollution, light pollution, noise pollution, toxins and poisons, random falsehoods in your mind facts that read as curse to be found on an amuelet dug up in some near(ish) future iteration of whatever the,, it is,, that we are doing right now
merryocha 11mo ago
I wish more people paid attention to air quality. I'm a delivery driver and air quality has a noticeable effect on my energy levels throughout the day and also my mood. Slightly rainy days are probably my favorite days to work because no one is outside digging up roads and kicking up tire dust with leaf blowers and the rain seems to clean the air a bit.
- xeromal 11mo ago
  As a motorcycle rider, it's always very noticeable. The stale air from the helmet coupled with the shit shit air from outside makes me very sleepy and you can develop a sore throat in a few hours
  - Ey7NFZ3P0nzAe 11mo ago
    You might want to lookup hypercapnia clinical signs to look for. Lile sweating, increase heart rate etc. (Source: resident)
PaulKeeble 11mo ago
Almost all of the problem is PM2.5 but its not the only pollution problem. For PM2.5 a simple N95/FFP2 mask will drop the particles you breath in to basically zero and remove the health consequences of them and as we saw in 2020-2021 you can happily run in them they don't restrict breathing much at all. You do not have to put up with the damage from polluted air alongside the exercise.
- deleted 11mo ago
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- homebrewer 11mo ago
  Respirators can't do anything about volatile components that have low boiling points: sulfur and nitrogen oxides, hundreds of often carcinogenic aromatic hydrocarbons released by burning any organic matter. If you wear a good FFP3 respirator in heavily polluted air, it's very noticeable that it doesn't filter out everything — the smell gets through. And it's a specific smell, reminds me of walking through charred ruins of a building that has burned down 5-10 years ago and never rebuilt.
  - gbear605 11mo ago
    I had a notable experience at a church sometime during COVID, where I was wearing an N95 mask. The church’s incense could be smelt partially through the mask, and the scent that made it through was much worse than the combined scent that you normally smell.
ck2 11mo ago
I am hoping by the end of the decade smartphones start having pm2.5 and co2 sensors built-in and then next decade smartwatches Once EVERYONE starts seeing air-quality on their phones every hour of the day everywhere they are, they will start to care and then eventually, maybe do something about the politics to improve air-quality Imagine the game-changer if air-quality was in the next iPhone They already make sensors that can go on a keyring so inside a phone is not implausible within a few years
- homebrewer 11mo ago
  I doubt it, maybe in rich countries where the air is already pretty good. There are enough places out there (mine included) where you can see and feel air pollution without using any sensors: limited visibility on the order of a few dozen meters, smell of burning coal and rubber tires in the air, windows blackened by soot. Everybody knows how terrible the air is, talks about it daily, and can't actually do anything about it. I've been advocating for closed windows and increased use of air purifiers and FFP3/N99 respirators, and had some limited success among people I know. People are often easily convinced once they see the state of their filter or respirator after a few days of use.
- dahart 11mo ago
  Yeah it’d be cool if the phones had sensors. Everyone can see local AQI already though; weather app has AQI, and you can tap on it for a local region map, as well as a table of pollutant details.
  - ck2 11mo ago
    the "local AQI" is usually from a single government sensor for 100 mile radius which is useless as pollution is highly localized (think neighbor idiots burning leaves all day) also doesn't tell you indoor air quality which where you sleep REALLY matters if the co2 is sky high best third party AQI network is PurpleAIR but even with them certain cities have few or none https://map.purpleair.com/air-quality-standards-us-epa-aqi https://map.purpleair.com/air-quality-standards-us-epa-aqi airgradient barely has any in some US states https://www.airgradient.com/map/ https://www.airgradient.com/map/ US doesn't even have mandatory air-quality sensors at airports, which it should because that's where most of the other weather measurements are coming from on most apps, even if you are 30-50 miles away
kakacik 11mo ago
Hiking in the hills / mountains is one of the healthiest sports there is, unless you already have messed up legs. Or other mountain sports, but at least those I do have additional risks of injury or death that most folks would find unacceptable. Not everybody has easy access to mountains, but then we all forge our paths through life and at least at certain points of life we have some wiggle room to choose where to spend the rest of it. Polluted big cities may (or may not) bring more wealth but there is a cost. I look from my balcony on a large forest which is natural reserve, begins right in front of us. On the other side of the village there is a 15km band of vineyards on steep hills. I go up and end up in wild hills fully covered in pine forests and actually OK for winter sports (planning to do skitour there tomorrow morning). I go the other side and its 100km wide lake with crystal clear water, highly swimmable in summer. Highway is few km away, 100m lower. Coming to city makes me realize the various not OK smells I didn't sense when I was living there. Not regretting the move (but sure as hell hoping some part of work will remain WFH so its not just kids reaping benefits of living on a more healthy and overall better place)
- deleted 11mo ago
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ChrisArchitect 11mo ago
Aside: OP are these stories just re-rigged versions of other source articles out there? https://www.ucl.ac.uk/news/2025/nov/air-pollution-may-reduce-health-benefits-exercise https://www.ucl.ac.uk/news/2025/nov/air-pollution-may-reduce... (https://news.ycombinator.com/item?id=46084057 https://news.ycombinator.com/item?id=46084057) https://www.euronews.com/health/2025/11/28/air-pollution-may-cut-into-health-benefits-from-exercise-study-finds https://www.euronews.com/health/2025/11/28/air-pollution-may...

188 points by ashishgupta2209 11mo ago

bluesky19283746 11mo ago

It sounds terrible . What will happend in the future?! The research doesn't differentiate between seasons , and every one knows how polluted the air is in the winter when everyone is heating their home and apartament.

colinb 11mo ago
One more reason to look to an electrically heated future. Where I live the air becomes unpleasant in winter as some neighbours heat their homes by burning what i can only assume are old tires and horse carcasses.
- tgsovlerkhgsel 11mo ago
  I remember as a kid visiting the home of a relative who had an old oven for wood/coal heating, even though the primary heating was now a gas (natural gas not gasoline) heater. The old oven remained though, and was used as a self-emptying trash can. When it filled up, a fire was lit to empty it. I don't remember what the sorting rules were (I assume "does it burn well and not smell up the apartment too badly when lighting it") and how common plastic packaging was back then, but I'm sure that the emissions coming out from the chimney were not a concern.
- lm28469 11mo ago
  Burning clean dry wood in a modern well maintained wood stove is surprisingly efficient and relatively clean (+ renewable) Of course if you burn trash none of that matters, but it's already illegal in pretty much any advanced societies.
  - colinb 11mo ago
    oh, it's illegal where I live. But some people pretty clearly ignore that. Enforcement doesn't seem to be a thing. I think this is one of those laws that falls into the category of things that we just have to rely on people's good will to carry out. Like small-time littering and not cleaning up after your dog, some people just don't seem to care. FWIW, I think - based on not feeling my throat close up most of the time - that the number of people who do this is small.
adrianN 11mo ago
In the future electric cars and heat pumps will improve the situation.
- edhelas 11mo ago
  And how the electricity will be made? Without any CO2 for sure! (or not... yet)
  - rafaelmn 11mo ago
    What does CO2 emissions of electric power plants have with air quality in cities ?
  - cinntaile 11mo ago
    Power plants are usually not placed inside cities. Less gasoline cars inside cities will definitely improve the local situation, not just limited to CO2.
  - cowsandmilk 11mo ago
    CO2 isn’t particulate matter. But more importantly, larger percentages of our electricity is being made without burning things.
  - hagbard_c 11mo ago
    Nuclear power is a good option, wind and solar are usable for charging batteries - either EV batteries or storage banks which can be used to charge EV batteries. The problem with wind and solar is that there is no long-term storage solution as of yet but single-day storage is already achievable. Once enough nuclear capacity has been built up I foresee wind turbines disappearing from the landscape since they are cumbersome bird-killing eyesores. Solar power is there to stay since buildings need roofing anyway and we'll soon be at a point where the price difference between 'passive' roof cladding and PV 'panels' is close to negligible so it makes sense to install PV roof cladding and get some power for free, especially in places where air conditioning is popular.
- ozim 11mo ago
  You still have break pads and tires particles floating around.

emacsahmed 11mo ago

[dead]

clumsysmurf 11mo ago

I look at the PM2.5 data for my city every day, and at this point (Nov) in the winter season, the only acceptable time to exercise is between 2PM-4PM after vertical mixing kicked in. Outside that duration, particulates are elevated after morning rush our, after evening rush hour, or during overnight inversion trapping evening rush hour + wood burning smoke until the next morning rush hour. This is one the main reasons why I would prefer working remote, it is hard to utilize this time well (for exercise) if you are in the office. At least with PM you can wear a mask, although I am still searching for the best one that works during intense exercise. Also wanted to point out "Trump EPA moves to abandon rule that sets tough standards for deadly soot pollution" https://apnews.com/article/epa-soot-air-pollution-trump-zeldin-deregulation-d7df5b24a159284e96b12958a840c3d8 https://apnews.com/article/epa-soot-air-pollution-trump-zeld...

krzat 11mo ago
> I am still searching for the best one that works during intense exercis Try a professional mask, like 3M 7500 with 2138 filters.
- clumsysmurf 11mo ago
  Thanks, that's one of the masks I use! Unlike the GVS SPM587 it has a quick release thing so you can get to your hydration for water and microplastics :/

Theodores 11mo ago

If only you could see it. In the big cities the air quality has improved, however, I am not sure if it really has, or if we are now just burning hydrocarbons more efficiently so that the particle sizes have become invisible. Put it this way, although cars are allegedly better than they were, fuel consumption hasn't dropped considerably. The cars are more numerous than ever, and, although there are EVs, there are still more ICE cars than there were in the good old days when petrol came with lead in it. I am not sure that most people in urban areas even know what good air tastes and smells like. I take a canal path through lush countryside, far from any cars for most of the way. This canal has an aqueduct (or is it a viaduct?) over a motorway and the contrast is incredible. You go from basically smelling flowers to air pollution and back to clean air again quite quickly, so the filth is totally noticeable. Note the cars on the motorway are going at speed, so they should be working efficiently (until a few decades ago 56 mph was what engines were optimised for regarding efficiency in the UK). If just living in a major city then you don't get this instant switch from bad to good air. So you just don't notice it. If you could see the filth, you would prefer a swimming pool that was pissed in, it is that toxic. If you do have to live in a city, my top tip is to find out if there are any meteorologists in town. If there are, buy a house next to where they are living. Anecdotal, however, I used to work with meteorologists and they would always live to the West of the city centre, to get cleaner air than those living in the east of the city, or further downwind. Again anecdotal, however, due to the canal and motorway experience described above, in post-industrial countries such as the UK, it is definitely the vehicles rather than any other source. Given the choice of microparticles that just get in your blood or clumps of big particles that you can eventually cough up and spit out, I would much prefer the latter. My hunch is that the legislation to improve vehicle emissions has optimised the exhaust for nanoparticles. Please prove me wrong!

softwaredoug 11mo ago
For urban areas the risk of air pollution is another reason for cities to have congestion pricing to support public transportation.
jwr 11mo ago
> I am not sure that most people in urban areas even know what good air tastes and smells like. I run air filters in my apartment throughout winter months, which tend to be the worst in terms of air quality here. When I go outside in the morning I can really smell the stuff in the air, for a brief moment, until I get used to it. But you definitely notice the difference!

softwaredoug 11mo ago

Before people freak out about their morning run, I’m very hard pressed to find 25 PM2.5 on this map of the US. (Note these numbers are AQI, you have to zoom into the bad AQI numbers and look at their PM2.5). Albeit it’s a Saturday morning, not rush hour. China and India look rough though. https://www.iqair.com/us/air-quality-map https://www.iqair.com/us/air-quality-map

thearrow 11mo ago
Please note that air quality in an area varies dramatically over time. You are looking at a current snapshot with maps like that. The map linked below has his more historical data and I can see several _weeks_ this past year in my area (which currently has very good air quality) where the PM 2.5 weekly average exceeded 25ug/m^3. https://map.purpleair.com/air-quality-raw-pm25 https://map.purpleair.com/air-quality-raw-pm25 Localized phenomena like a neighbor starting a fire, up to the activity of nearby factories and power plants, up to national and global phenomena like wildfires and weather patterns, all have dramatic effects. Looking at an air quality map once and determining that you don’t have to think about air quality because you’re in the US is a mistake. Exercise outdoors is a wonderful thing, obviously, but there are some days, even in the US, where you might think twice or even consider shifting your exercise to a different (less-polluted) time of the day.
- metadope 11mo ago
  > Localized phenomena like a neighbor starting a fire, Summer evenings at home in my small Ohio village are often a health hazard, a polluted nightmare driven by the perverse compulsive ignition of so-called 'recreational' yard fires by pyromaniac neighbors. If it is an Ozone Action day and/or a Heat Advisory day, it is near certain that one or more of the Don't Tread On Me jamokes who live nearby will come out of their houses at sunset, pile a bunch of garbage into a 55-gallon drum or a circle of rocks, sprinkle with accelerant, toss a match and back away. Eyes glazed, they'll watch for a minute, then go back inside, sometimes coming back out every ten minutes or so to refuel the fire, other times letting it blaze until the original pile is down to embers. In any case, there is a new plume of local smoke to add to the day's irritants. It is a startling phenom to observe, let alone endure. The behavior is made all the more crazy, imho, by the presence of children. These are parents, asserting their rights to burn, and teaching their children to Live Free Or Die. It seems to me to be driven by a rebelliousness, part of the anti-woke wave, country-fried counter-culture, as in "I got your global warming right here, pard". It's like, listening to country music stations and realizing how many (most!) contemporary and historical Country songs are themed around alcohol-worship. But I digress. I apologise. I was triggered by the mention of 'localized phenomena' and the horrified realization that so many of my fellow citizens are self-destructive cray-cray.

kqr 11mo ago

I want to pull two quotes from the article. > “Our findings emphasise that exercise remains beneficial even in polluted environments,” lead researcher Professor Po-Wen Ku said in a statement. [...] “We don’t want to discourage people from exercising outdoors,” said Co-author Professor Paola Zaninotto. The health effects of exercise outdoors are combined from two effects: - Positive effects due to exercise. These start out strong but level off after a while. - Negative effects due to pollution. These increase almost linearly with time spent outside. One might ask, is there an amount of daily exercise at which the negative effects overpower the positive ones? Yes, in a handful of cities around the world, after a few hours of exercise, the pollution makes additional outdoors exercise actually harmful. But almost everywhere a marginal minute of exercise provides a positive effect on health regardless of time already spent exercising, and there is nowhere in the world where something like an hour of exercise a day is a net negative. Get out there. Pick an active means of commuting (cycling, running, walking, skiing, rollerblading, skateboarding, unicycling) and don't worry so much about pollution unless you live in one of those single-digit cities which I forget where they are, but probably concentrated in Asia. (I feel bad about typing this out without linking to the source. I'm looking for it in my notes!)

ta12653421 11mo ago
I remember an interview with the producthead of Google Earth (the desktop client), she said when photographing all the streets, the cars also checked for air pollution: She mentioned a capital in Europe, where the amount of particles under certain sizes differed by 10x from one crossing to the next.
- potato3732842 11mo ago
  The measurement may very well be accurate but statements like that should set off massive red flags and not be taken at face value. A factor of ten difference for something that just kinda diffuses through the air doesn't "just exist". You don't get gradients like that "naturally" for the most part. It's the result of something. Maybe there's a source something is upwind of and something else is downwind of. Maybe there's conditions causing it to concentrate. Or it varies 10x day to day, but on an average basis it equals out. Etc. Etc.

qprofyeh 11mo ago

If you have ever been to a city that has banned fossil fuels then you can absolutely tell the difference, to most of the overpopulated European cities that I have visited. It’s astonishing how peaceful and comfortable it is to run or even stroll when every breath is just 100% refreshing; you feel 10 pounds lighter. Meanwhile the blackened filter of our home HVAC needs replacement again… and allergies.

unglaublich 11mo ago
Sadly, fossil fuel (pollution) has been marketed as a masculine culture thing now. In the free (=individualistic) West, I expect it to stick around for at least another 50 years.
- labcomputer 11mo ago
  I expect less than 10. Once you drive an EV, every big noisy diesel feels impotent and gutless. Kind of like a small yappy dog that’s all bark and no bite. There’s just nothing like the zero-lag gut-punching acceleration of an EV.
  - array_key_first 11mo ago
    Unfortunately it's not really up to us plebs, it's up to the rich and powerful, who have every incentive in the world to continue fossil fuel use. Trump has outright said he's pro fossil fuels and his policy choice shows it. If there was a proposal to ban or limit EVs in the US, I would not at all be surprised. These people do not care about you or me or all, just their pocket linings.
  - yosito 11mo ago
    Like many other "masculine culture" things, the propaganda sold to men about what's masculine doesn't necessarily have a connection to reality.
  - Timon3 11mo ago
    The industry is trying their best to fight against it. The EU is currently planning to ban new ICE cars from 2035, but the conservative German government & car lobbyists are trying to get them to drop those plans... That, combined with high tariffs for cheap asian EVs will probably artificially keep us on ICEs for a while longer.

unglaublich 11mo ago

And all the while, nothing is done to get old 2-stroke mopeds of the road in Europe. It’s such a low hanging fruit to get those hyper polluters out of cities but in an individualistic society, personal cult status seems more important than common health.

dylan604 11mo ago
These seemed like the obvious EV conversion target to me before cars for Europe. Why have these not been converted to EV?
- unglaublich 11mo ago
  They have, but individuals value nostalgia more than practicality.
- seec 11mo ago
  The problem is that they are not cost competitive at the time of sales and the type of people who buy those are not exactly the smartest when it comes to total cost of ownership calculation. Over time an electric version would be much cheaper (a few hundred kilometers depending on electricity price) but it's also not as convenient/capable/performant so it's a not exactly an easy sell to the target customer. I do agree that they are highly annoying but the reality is that they are still in use because there is no real equivalency in the electric world.
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potato3732842 11mo ago

Cities have mostly only gotten cleaner with time. This is way, way, way down the list of things that I'm worried about killing me.

metalman 11mo ago

air pollution, light pollution, noise pollution, toxins and poisons, random falsehoods in your mind facts that read as curse to be found on an amuelet dug up in some near(ish) future iteration of whatever the,, it is,, that we are doing right now

merryocha 11mo ago

I wish more people paid attention to air quality. I'm a delivery driver and air quality has a noticeable effect on my energy levels throughout the day and also my mood. Slightly rainy days are probably my favorite days to work because no one is outside digging up roads and kicking up tire dust with leaf blowers and the rain seems to clean the air a bit.

xeromal 11mo ago
As a motorcycle rider, it's always very noticeable. The stale air from the helmet coupled with the shit shit air from outside makes me very sleepy and you can develop a sore throat in a few hours
- Ey7NFZ3P0nzAe 11mo ago
  You might want to lookup hypercapnia clinical signs to look for. Lile sweating, increase heart rate etc. (Source: resident)

PaulKeeble 11mo ago

Almost all of the problem is PM2.5 but its not the only pollution problem. For PM2.5 a simple N95/FFP2 mask will drop the particles you breath in to basically zero and remove the health consequences of them and as we saw in 2020-2021 you can happily run in them they don't restrict breathing much at all. You do not have to put up with the damage from polluted air alongside the exercise.

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homebrewer 11mo ago
Respirators can't do anything about volatile components that have low boiling points: sulfur and nitrogen oxides, hundreds of often carcinogenic aromatic hydrocarbons released by burning any organic matter. If you wear a good FFP3 respirator in heavily polluted air, it's very noticeable that it doesn't filter out everything — the smell gets through. And it's a specific smell, reminds me of walking through charred ruins of a building that has burned down 5-10 years ago and never rebuilt.
- gbear605 11mo ago
  I had a notable experience at a church sometime during COVID, where I was wearing an N95 mask. The church’s incense could be smelt partially through the mask, and the scent that made it through was much worse than the combined scent that you normally smell.

ck2 11mo ago

I am hoping by the end of the decade smartphones start having pm2.5 and co2 sensors built-in and then next decade smartwatches Once EVERYONE starts seeing air-quality on their phones every hour of the day everywhere they are, they will start to care and then eventually, maybe do something about the politics to improve air-quality Imagine the game-changer if air-quality was in the next iPhone They already make sensors that can go on a keyring so inside a phone is not implausible within a few years

homebrewer 11mo ago
I doubt it, maybe in rich countries where the air is already pretty good. There are enough places out there (mine included) where you can see and feel air pollution without using any sensors: limited visibility on the order of a few dozen meters, smell of burning coal and rubber tires in the air, windows blackened by soot. Everybody knows how terrible the air is, talks about it daily, and can't actually do anything about it. I've been advocating for closed windows and increased use of air purifiers and FFP3/N99 respirators, and had some limited success among people I know. People are often easily convinced once they see the state of their filter or respirator after a few days of use.
dahart 11mo ago
Yeah it’d be cool if the phones had sensors. Everyone can see local AQI already though; weather app has AQI, and you can tap on it for a local region map, as well as a table of pollutant details.
- ck2 11mo ago
  the "local AQI" is usually from a single government sensor for 100 mile radius which is useless as pollution is highly localized (think neighbor idiots burning leaves all day) also doesn't tell you indoor air quality which where you sleep REALLY matters if the co2 is sky high best third party AQI network is PurpleAIR but even with them certain cities have few or none https://map.purpleair.com/air-quality-standards-us-epa-aqi https://map.purpleair.com/air-quality-standards-us-epa-aqi airgradient barely has any in some US states https://www.airgradient.com/map/ https://www.airgradient.com/map/ US doesn't even have mandatory air-quality sensors at airports, which it should because that's where most of the other weather measurements are coming from on most apps, even if you are 30-50 miles away

kakacik 11mo ago

Hiking in the hills / mountains is one of the healthiest sports there is, unless you already have messed up legs. Or other mountain sports, but at least those I do have additional risks of injury or death that most folks would find unacceptable. Not everybody has easy access to mountains, but then we all forge our paths through life and at least at certain points of life we have some wiggle room to choose where to spend the rest of it. Polluted big cities may (or may not) bring more wealth but there is a cost. I look from my balcony on a large forest which is natural reserve, begins right in front of us. On the other side of the village there is a 15km band of vineyards on steep hills. I go up and end up in wild hills fully covered in pine forests and actually OK for winter sports (planning to do skitour there tomorrow morning). I go the other side and its 100km wide lake with crystal clear water, highly swimmable in summer. Highway is few km away, 100m lower. Coming to city makes me realize the various not OK smells I didn't sense when I was living there. Not regretting the move (but sure as hell hoping some part of work will remain WFH so its not just kids reaping benefits of living on a more healthy and overall better place)

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ChrisArchitect 11mo ago

Aside: OP are these stories just re-rigged versions of other source articles out there? https://www.ucl.ac.uk/news/2025/nov/air-pollution-may-reduce-health-benefits-exercise https://www.ucl.ac.uk/news/2025/nov/air-pollution-may-reduce... (https://news.ycombinator.com/item?id=46084057 https://news.ycombinator.com/item?id=46084057) https://www.euronews.com/health/2025/11/28/air-pollution-may-cut-into-health-benefits-from-exercise-study-finds https://www.euronews.com/health/2025/11/28/air-pollution-may...