> “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!)
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.
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.
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.
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!
> 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!
Lots of particles cars emit are from tires and break pads. I think someone was measuring that but I don’t have sources but most likely I read that somewhere in the comments of HN.
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"
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 :/
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.
Power plants are usually not placed inside cities. Less gasoline cars inside cities will definitely improve the local situation, not just limited to CO2.
EVs generate far, far less brake pad dust, most of their braking is regeneration via the motors.
Tires get more efficient every year, dust has reduced as the companies compete to make them last longer, and we're finally seeing the tire industry respond to pressure to reduce toxic runoff. Michelin's been removing phenols, for instance: https://resicare.michelin.com/news/michelin-resicare-resin-1...
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.
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.
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!)
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.
>Get out there
Very true, particularly as lives tend to be more cerebral nowadays. It helps with balance.
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.
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
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!
For urban areas the risk of air pollution is another reason for cities to have congestion pricing to support public transportation.
> 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!
Exhaust fumes were easy to optimize.
Lots of particles cars emit are from tires and break pads. I think someone was measuring that but I don’t have sources but most likely I read that somewhere in the comments of HN.
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-zeld...
> I am still searching for the best one that works during intense exercis
Try a professional mask, like 3M 7500 with 2138 filters.
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 :/
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.
In the future electric cars and heat pumps will improve the situation.
And how the electricity will be made? Without any CO2 for sure! (or not... yet)
CO2 isn’t particulate matter. But more importantly, larger percentages of our electricity is being made without burning things.
Power plants are usually not placed inside cities. Less gasoline cars inside cities will definitely improve the local situation, not just limited to CO2.
What does CO2 emissions of electric power plants have with air quality in cities ?
You still have break pads and tires particles floating around.
EVs generate far, far less brake pad dust, most of their braking is regeneration via the motors.
Tires get more efficient every year, dust has reduced as the companies compete to make them last longer, and we're finally seeing the tire industry respond to pressure to reduce toxic runoff. Michelin's been removing phenols, for instance: https://resicare.michelin.com/news/michelin-resicare-resin-1...
I specifically said „improve“ not „eliminate air pollution completely“.
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.
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.