> “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!)

China and India look rough though.

https://www.iqair.com/us/air-quality-map

https://www.ucl.ac.uk/news/2025/nov/air-pollution-may-reduce... (https://news.ycombinator.com/item?id=46084057)

https://www.euronews.com/health/2025/11/28/air-pollution-may...

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

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!

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)

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

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-zeld...