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[Closed] Is social distancing done with in mountain biking?

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I’m not sure how you know that most infections are indoors

This is the classic report:

https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1

No one seems to have done anything similar in the UK.

so you think it’s ok to kill 70 year olds

National over-reacting week again.

I’ve no idea how you could know that none of your friends have the virus?

I can look at the infection rates in the UK as a whole (thankyou ONS). Something like 0.25% of the population are infected. I would need to go on a bike ride with about 400 people. Indoors.

So Cummings is stupid, and Boris isn’t brave enough to fire him

Or perhaps this is the kind of behaviour they are expecting of us?


 
Posted : 24/05/2020 10:07 pm
 Spin
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Perhaps you think my mother shouldn’t be scared to go back into the nursing home we took her out of at the beginning of February when it became obvious tens of thousands were going to die in UK nursing homes?

I think you've misunderstood me. I was suggesting that sometimes people's fear leads them to behave in a way that could be interpreted as being a dick. I think both bits of that equation are understandable and that it probably explains the incident with someone rejecting help you mentioned upthread.


 
Posted : 24/05/2020 10:08 pm
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Groups of 5 and one of 10 in the wyre forest today 😟


 
Posted : 24/05/2020 10:21 pm
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don't see a problem with 3/4/5 strong groups, we all think we're much more likely to catch/spread it working on site as distancing is much harder/impossible to do.

i would think on a 3 hour ride we would probably only spend a minute or 2 closer to someone than 2M so vertually no risk.


 
Posted : 24/05/2020 10:51 pm
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It can't be that bad if NI are allowing groups of six outside. Lets all stop panicking shall we for seeing a few MTBers togethers, plus MTBing has nothing to do with it - plenty of walkers breaking the +1 rule.

As mentioned its widely accepted by scientists based on other similar viruses that outdoor exposure drastically limits the spreading of this virus.

Move on.


 
Posted : 24/05/2020 11:02 pm
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Yeah, but it’s not really killing that many healthy people who congregate outdoors and might on occasions be closer than 2m is it?

Indeed hopefully not. But what could be happening is those fit healthy outdoorsey types can carry the virus, and pass it alone to someone who it would likely seriously affect. Might even be a week till they feel even remotely unwell or with the lightest of symptoms.
But until symptoms present themselves if at all those people are capable of carrying and passing it on.
Thats the worry especially as death rate has fallen significantly indicating new infections are or were a month ago low.
What we now need is to see a serious decline in infections, knowing that from those infected a percentage wont survive and we'll have that rate for as long as the infections remain steady or then drop, and subsequently a month or so from that time the death rate will also drop significantly then I would expect to stop abruptly. Well hopefully abruptly.


 
Posted : 24/05/2020 11:15 pm
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Have you ever caught an old-skool cold while out cycling with a few friends?

Or did you catch all those colds by going to a crowded pub, or sitting on a crowded train, or teaching a class of sniffly kids?


 
Posted : 25/05/2020 12:04 am
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@spin

I think you’ve misunderstood me. I was suggesting that sometimes people’s fear leads them to behave in a way that could be interpreted as being a dick. I think both bits of that equation are understandable and that it probably explains the incident with someone rejecting help you mentioned upthread.

Sort of .... I think my original point is/was on two other levels.
1) Assumption that anyone (under 80 ish) who doesn't "want" to catch CV is a dick
2) Inability to see that if someone doesn't want to be infected you should respect that

If you start off with an assumption the crashed guy really doesn't want CV for whatever reasons and respect that then the crashed rider really had no other choice but shout. It's not a situation you have time for 20 questions.

What greatly concerns me is that overwhelmingly from that thread most can't get past #1.

This then leads to:

i would think on a 3 hour ride we would probably only spend a minute or 2 closer to someone than 2M so vertually no risk.

I really can't even begin...

Lets all stop panicking shall we for seeing a few MTBers togethers, plus MTBing has nothing to do with it – plenty of walkers breaking the +1 rule.

As mentioned its widely accepted by scientists based on other similar viruses that outdoor exposure drastically limits the spreading of this virus.

.. cycling behind someone for 1/2 hour or more?
.. like magic tennis balls and magic footballs..

It can’t be that bad if NI are allowing groups of six outside.

??? You think the virus changes behaviour as it crosses the border?


 
Posted : 25/05/2020 12:13 pm
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oldnpastit

Have you ever caught an old-skool cold while out cycling with a few friends?

Or did you catch all those colds by going to a crowded pub, or sitting on a crowded train, or teaching a class of sniffly kids?

Certainly not ALL ... but what exactly do you mean by catching a cold?
I personally rarely get colds developing, once a decade on average I'll have more than 1/2d of sniffles and headache.
As far as I know I've not had flu ever in 50+yrs...

I've almost certainly carried the virus and passed it to others though.


 
Posted : 25/05/2020 12:21 pm
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The government could resolve all these questions at a stroke by funding some research into (say) a thousand cases and tracking where they all picked up their infection.

Then we would *know* how often people get it from cycling in groups, or going to school, or sitting on an underground train, or whatever.

For whatever reason this hasn't happened in this country.


 
Posted : 25/05/2020 12:28 pm
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The government could resolve all these questions at a stroke by funding some research into (say) a thousand cases and tracking where they all picked up their infection.

Then we would *know* how often people get it from cycling in groups, or going to school, or sitting on an underground train, or whatever.

Or they could simply use the existing studies carried out elsewhere ... at least whilst they carry out their own... though quite how you'd get reliable results unless you completely controlled everything else I don't know. How do you seperate a teacher who went to a supermarket after school then went cycling for a week plus until they have something to actually test?

For whatever reason this hasn’t happened in this country.

Hiding the results would be very difficult and the results woulds almost certainly not allow them to continue the current herd immunity by stealth approach.


 
Posted : 25/05/2020 12:45 pm
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??? You think the virus changes behaviour as it crosses the border?

Exactly the point Einstein.. why is it OK there and not here.

The Dutch and Belgian study that you may have read about exercising was largely debunked with quite a few flaws.


 
Posted : 25/05/2020 3:05 pm
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Exactly the point Einstein.. why is it OK there and not here.

What's do you mean by OK?
This is the real problem... not just for MTB but every aspect of life with CV.
It's not a binary ... each country has sets of measures to reduce infections but these are not specific. In the UK and NI we have 4 sets .. the ROI another etc. but

The Dutch and Belgian study that you may have read about exercising was largely debunked with quite a few flaws.

I'm not referring to any specific study.
Back to binary .. you are free to go out with a mate who can also go out with a mate and you are free to share waterbottles so long as you leave it on the ground and don't go within 2m of each other. I haven't seen a law prohibits this ... just as trail centres in the UK have signs telling you to stay 2m apart.
I haven't seen a study where travelling through the exhaled breath of someone with a 1/4 second gap has shown this to be "safe" and more than a study saying why tennis balls can't carry CV or sharing a water bottle or a joint is OK so long as you stay 2m apart when passing it.


 
Posted : 26/05/2020 10:01 am
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Yes, the 2m rule is only relevant when people are stationary, so riding at speed 2-3m behind someone is obviously a problem.

NI can have different rules because they have made a different risk assessment. That may be based on the much lower prevalence of disease, or rates of transmission (R), or simply politics.

I worry about the perception of the general public thinking cyclists / MTBers are entitled pricks. When many people are going to great effort to keep themselves isolated, it is galling to see people who think the rules (however sensible / non-sensical you may feel they are) are being ignored. There is a lot of talk about cycling (and sport in general) being part of the 'new normal' which is great. But at the same time there's a lot of people making us look like morons.

I went on a solo ride where I (slowly) caught another riding duo. It would have looked like we were riding as a threesome. I felt weirdly self-conscious until I could distance them.


 
Posted : 26/05/2020 10:36 am
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I worry about the perception of the general public thinking cyclists / MTBers are entitled pricks.

You may well be right, and given they already think that it would be wise not to provide them with any more ammo.

It's definitely not just cyclists though. It seems to have become the norm in all walks of life now. I'm not sure people really know what the rules are any more.


 
Posted : 26/05/2020 10:45 am
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I dont think its just mountain bikers who are congregating. We  up in the Peak District yesterday and saw numerous group of 6 to 10 people all of the same sex so highly unlikely to be a single household. Other groups were clearly 2 or more families out for the day.


 
Posted : 26/05/2020 10:47 am
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What’s do you mean by OK?

Steve, all 4 nations are advised by the same group - SAGE. So again why has NI moved forward with larger group allowance than England. I'd also add that Outdoor markets will be allowed from the 1st June, thats certainly going to be a crowded affair.

You have to remember there are other factors here at play than just the science, like politics.

The choice of gathering with one person or 6 people is irrelevant when social distancing is maintained when outdoors, the risk remains the same - virtually zero chance of infection due to environmental factors as is well documented.

Similarly look at our fellow European countries and what they've been doing since the middle/early parts of May - the infection rate hasn't increased so we have some precedent to show that the risk of smallish spaced out outdoor interactions does not cause an influx of infection.


 
Posted : 26/05/2020 10:54 am
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Yes, the 2m rule is only relevant when people are stationary, so riding at speed 2-3m behind someone is obviously a problem.

Except that 2m is an outlier anyway. In plenty of other countries, the 'safe' distance is 1m or 1.5m (Germany I think). All the stuff I've read on viral transmission suggests that the biggest risk is indoors - offices, restaurants, public transport, where people are subjected to exhaled virus globs for extended periods of time.

Also some really interesting stuff on humidity. Apparently the high transmission in ski resorts wasn't down to chalets or bars predominately, but ski lifts where skiers were packed together in bubbles, globes and telecabines. Low temperatures meant humidity rapidly rises to close to 100% and, in turn, larger exhaled globules of viral matter remain suspended in the air far longer than they would in a drier environment. Cue inhalation of lots of virus and rapid spread. The inference for shops and offices is that reducing humidity is an important step in minimising spread. Or so my mate who is brighter and better connected than me and runs an office says.

I'm certainly not saying any of this means people should ride bikes in groups, personally I choose not to - or would do if I weren't convalescing in a hammock - but it's likely to be relatively low risk behaviour. I always thought skiing was evil 🙂

ps: assuming what has wiped me out for the last 11 weeks is covid-19 - waiting for antibody test result, but had loads of the obvious symptoms - you really don't want the long-tail recovery version of this thing, no matter how fit and healthy you might be.


 
Posted : 26/05/2020 11:11 am
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Yes, the 2m rule is only relevant when people are stationary, so riding at speed 2-3m behind someone is obviously a problem.

Obviously?

Not sure it is really. Before SteveXTC jumps down my throat again I don't condone riding in pairs/groups, I think it's an unessecary risk. But I dont think its as bad as some of the moraly superior beings on this thread are making it out to be.

Indoors you breath is going to hang arround in the air untill any droplets fall to the floor or get diluted to the point of no significant risk, hence a ~2m radius is fairly easy to visualise how that works, you can see your breath on a cold day, it doesnt travel very far.

Riding a bike at 10mph thats 5m/s, so while there is probably a plume of breath behind you, its being mixed with several cubic meters of turbulent air every second.

Which has more virus particles, some stagnant air thats been breathed in and out for 15 minutes (the guidelines) or 2l of breath diluted into ~5m3 of turbulent air? Even before any breeze effect carries it away at an angle.


 
Posted : 26/05/2020 11:12 am
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The trouble with the virus is that you can have it, and be asymptomatic and contagious, which is scary. So you wont know your ill and spread it.

Also it's not just over 80's. Plenty of people with well controlled health issues have died as a result of catching it.

I personally think groups are a bit too soon and can't be doing much for our image, reading how busy Surrey Hills was and car parks more than full... And any goodwill we had is disappearing quickly.

There's still more infections and deaths occurring than when the lockdown started.


 
Posted : 26/05/2020 11:13 am
 poly
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This is the classic report:

https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1

Have you actually read that (not yet peer reviewed) paper?
It only looks at "outbreaks" with multiple infections from a single "index patient".

If I've understood their data correctly 80% of the cases were transmission within a household, not exactly surprising, but it does mean there's not a huge amount of data on the "more interesting" inter-household transmissions.

Their own discussion notes, "Indoors is where our lives and work are in modern civilisation." That is subtle but important, its highlighting that there is a bias in the data, which shouldn't be inferred to say that outdoors is intrinsically safer, rather that since people spend most of their time indoors, there are more infections indoors. Its a bit like saying most car accidents happen on roads. Moreover they note, "Our study does not rule out outdoor transmission of the virus." and go on to explain that a large part of the study included periods where there were restrictions on movement in place ("lockdown").

No one seems to have done anything similar in the UK.

Not really surprising. Firstly, they have data going back to the start of the year, and submitted this in April. Secondly, they have much more rigorous case data in China (rightly or wrongly) - and even they note inconsistencies in the detail behind each case.

To be clear I'm not suggesting that risk isn't lower outside, but be very cautious about inferring indoor/outdoor risk from studies with bias on how much indoor/outdoor exposure there was, and even more cautious about assuming that a group of people riding in close proximity to each other is comparable to "outdoor risk" - because any studies that do come along for outdoor risk are unlikely to test or model those scenarios, v's passing interaction, brief conversation, and outdoors following social interaction - or at the other extreme crowded beaches, sports venues and music festivals. I'd also be very cautious about inferring data from different regions, because the virus doesn't change its behaviour but people do, environmental conditions are different (even seasonally) and hygiene behaviours like coughing, spitting, wearing masks will all vary too.

I’ve no idea how you could know that none of your friends have the virus?

I can look at the infection rates in the UK as a whole (thankyou ONS). Something like 0.25% of the population are infected. I would need to go on a bike ride with about 400 people. Indoors.

You see that is the problem with the ONS publishing data, people will take it and manipulate it to suit their underlying bias/belief. What that data tells you is that you can't know that none of your friends are infected. It may be relatively unlikely, but the thing about very unlikely things is they happen all the time (otherwise nobody would win the lottery, premium bonds etc). Even if we apply your logic to the scenario lets say 4 riders in a group, then if 100 groups went out on Sunday, then one of them just became a new outbreak cluster - we've no way to predict who, until those people start to display symptoms. Assuming asymptomatic transmission is a real problem they've then infected another 4*N people by the end of the week, and by the end of the following week they in turn infected 4N^2 repeat for all similar activities, and groups and suddenly its spiralling out of control. Or we could not ride in groups, and avoid the problem...


 
Posted : 26/05/2020 11:26 am
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mountain bikers, walkers, people in general are not following the guidelines/rules.

I guess from a personal level, what annoys me is when I have gone to the effort of following the rules, and others choose not to or feel that they don't apply to them.

I do wonder if when the government set out all these rules etc that there is some 'contingency' in them, knowing that a large chunk of people wont follow them.


 
Posted : 26/05/2020 11:27 am
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mountain bikers, walkers, people in general are not following the guidelines/rules.

This is the situation I've observed over the weekend, with a big uptick in people basically not giving a shit yesterday eve.

Mostly walkers and motorists meeting in groups though, relatively few MTBers despite the fine weather and sunshine.

It's almost as if something's happened that's made people think "oh well, sod it then". No idea what that could have been.


 
Posted : 26/05/2020 11:37 am
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Mr Pea and I avoided the bank hol crowds yesterday by setting off for a ride at 4am. Saw the sun rise, had a great ride in beautiful weather, home by 8am.


 
Posted : 26/05/2020 11:51 am
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No one else gives a shit now, walkers, families, etc.

I may bend the rules now but still very small group and we've all been self isolating or solo riding for months and don't come into contact with others. We don't interact with others on rides, although have to make some effort to avoid other people walking who don't care.

Common sense used. CumGate has told us we can just apply our own logic and common sense apparently and should have all along.


 
Posted : 26/05/2020 12:29 pm
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How do you seperate a teacher who went to a supermarket after school then went cycling for a week plus until they have something to actually test?

By using multivariate statistics in a big study with lots of data, hard to do but not imposdible.


 
Posted : 26/05/2020 12:34 pm
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Out on a walk yesterday and it was busy with folk everywhere. Can hardly blame them, it's been hard going for everyone and the "rules" seem to be easing... Most people were trying to be sensible as far I could see, I saw family groups,  a couple of groups of mountain bikers, and every-one seemed to be able to rub along.


 
Posted : 26/05/2020 12:45 pm
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CumGate

Is that an OTT reaction to the "how do you open gates" thread?


 
Posted : 26/05/2020 12:47 pm
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I think the accepted wisdom is that there is very little risk of spreading the virus when outside.

Yes, this is my reading of the evidence. see below for a good summary from 'an expert'. No contact is without risk but mountain biking in small groups and keeping some reasonable distance when you stop seems a very low risk activity to me.

What has 2m got to do with it? Is this a magic number?

Riding behind someone 1/4 sec behind them through woodland you might as well forget 2m when you stop.

Why would breathing in what someone exhaled 1/4 sec ago be safe?

This piece explains it pretty well - it’s from a professor of epidemiology, so has some credence

This seems quite informative in tackling the assertion that cycling is dangerous because you get close to other people at times.

https://www.erinbromage.com/post/the-risks-know-them-avoid-them

"In order to get infected you need to get exposed to an infectious dose of the virus; based on infectious dose studies with MERS and SARS (and this one), some estimate that as few as 1000 SARS-CoV2 viral particles are needed for an infection to take hold. Please note, this still needs to be determined experimentally, but we can use that number to demonstrate how infection can occur. Infection could occur, through 1000 viral particles you receive in one breath or from one eye-rub, or 100 viral particles inhaled with each breath over 10 breaths, or 10 viral particles with 100 breaths. Each of these situations can lead to an infection

"The exposure to virus x time formula is the basis of contact tracing. Anyone you spend greater than 10 minutes with in a face-to-face situation is potentially infected. Anyone who shares a space with you (say an office) for an extended period is potentially infected. :
...
Indoor spaces, with limited air exchange or recycled air and lots of people, are concerning from a transmission standpoint.

If you are sitting in a well ventilated space, with few people, the risk is low.
….
If I am outside, and I walk past someone, remember it is “dose and time” needed for infection. You would have to be in their airstream for 5+ minutes for a chance of infection. While joggers may be releasing more virus due to deep breathing, remember the exposure time is also less due to their speed."


 
Posted : 26/05/2020 1:02 pm
 D0NK
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I like how we're all sofa-epidemiologists now. chance of getting covid is probably higher going to buy food than going on a group ride, maybe even much higher, still possible tho and gonna be a huge kick in the plums if you do end up spreading it between yourselves and potentially everyone you go near.

You need to buy food, you don't need to ride with a bunch of other people, you can make the choice and most of us have probably bent the rules in some way so we probably shouldn't judge you for it, but you can't justify it with "there's minimal risk"


 
Posted : 26/05/2020 1:30 pm
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b33k34

If I am outside, and I walk past someone, remember it is “dose and time” needed for infection. You would have to be in their airstream for 5+ minutes for a chance of infection. While joggers may be releasing more virus due to deep breathing, remember the exposure time is also less due to their speed.”

I'm all with that up to ....

but mountain biking in small groups and keeping some reasonable distance when you stop seems a very low risk activity to me.

The first part seems to be the actual definition of mountain biking or group riding?
You sit behind or in front of someone for 5+ minutes... a very moderate 11.8 mph is 5ms-1 or you breath in what someone just breathed/coughed out a second ago if you keep 5m apart... or 2 seconds at 10m apart (etc.) obviously a fair bit of the time most of us are going at least double that speed... and group road riding ???


 
Posted : 26/05/2020 2:18 pm
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I do wonder if when the government set out all these rules etc that there is some ‘contingency’ in them, knowing that a large chunk of people wont follow them.

I read somewhere that gov were surprised just how compliant the general population were during initial lockdown..


 
Posted : 26/05/2020 2:40 pm
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I guess from a personal level, what annoys me is when I have gone to the effort of following the rules, and others choose not to or feel that they don’t apply to them.

I believe that is what is now known as the Cummings Defense.


 
Posted : 26/05/2020 2:51 pm
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The first part seems to be the actual definition of mountain biking or group riding?
You sit behind or in front of someone for 5+ minutes… a very moderate 11.8 mph is 5ms-1 or you breath in what someone just breathed/coughed out a second ago if you keep 5m apart… or 2 seconds at 10m apart (etc.) obviously a fair bit of the time most of us are going at least double that speed… and group road riding ???

Except you don't really do you?

As I pointed out, your breathing roughly every second. A couple of litres of air, into your wake, assume your wake is about 1m2 then that's a dilution factor of 1:2500, and you're not going to be within those few bike lengths of your mate very often. On a climb you're more likely to be side by side, on a descent you'l leave a gap so their mincing doesn't ruin your flow.

It's still greater than zero risk, but I'm not convinced it's actually as bad as half the recreational stuff we're now allowed to do like cafe's open for takeaway coffee / cake / ice cream mid ride.


 
Posted : 26/05/2020 2:57 pm
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Oh so the majority of people who have died are over 70, well that's alright then. But it isn't, because these over 70's are someones much loved family member.

Having seen a friend (you know who you are) who is very fit, healthy and still young trying to recover from C19 after many, many weeks - trust me none of you want to catch this virus.

This riding in large groups, or smaller groups, who don't live together or who aren't obeying the rules has been going on since day 1.

I decided to stop riding the local trails (which I've done for over 20 years) because they are too narrow to pass safely, mtbers treat them as though they are a trail centre. Also every one in the area has discovered them and is walking or riding them, even the really secret bits.


 
Posted : 26/05/2020 3:19 pm
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The first part seems to be the actual definition of mountain biking or group riding?
You sit behind or in front of someone for 5+ minutes…

I agree with this.

As I pointed out, your breathing roughly every second. A couple of litres of air, into your wake, assume your wake is about 1m2 then that’s a dilution factor of 1:2500

Right. But we know the 2m radius thing is the rule, and that takes into account any 'dilution factor' you care to mention.

When you exercise, you breath more often AND more deeply. It's a multiplicative effect. So you multiply respiratory rate and tidal volume together - in medicine this would be called your minute volume. This will increase 25-30 fold during peak exercise compared with rest. So you're shifting 25-30 x more air. In addition to that, by breathing more deeply, you are recruiting alveoli in the depths of your lungs which are not as active at rest. It's certainly plausible that these alveoli have a different concentration of viral particles.

I guess it depends on how you ride in a pair. I agree, if you're alongside 1-2m away it seems low risk intuitively. But on singletrack climbs you could easily be riding directly behind someone. There are other factors too. If you're meeting someone, you increase the likelihood you'll borrow their multitool or have a bounce on their bike etc. Probably some people will lift-share etc.

I, too, think this is probably a low risk activity. But I don't really know, and I'm very uncomfortable with the idea that people can just think they know better than the advice. To quote George Carlin: "Think of how stupid the average person is, and realize half of them are stupider than that.' Plenty of people will do stupid virus-spreading stuff if they're permitted to decide the rules are for bending.


 
Posted : 26/05/2020 4:22 pm
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Right. But we know the 2m radius thing is the rule, and that takes into account any ‘dilution factor’ you care to mention..........

I can see your point, I'm just struggling to visualize how riding behind someone is greater exposure than say sitting 2m away facing them in a park. To give an analogy we can all relate to, you know how bad your BO is in the beer garden (2m social distanced) after an all day epic ride? Yet you couldn't smell your mate coming down the last descent (what we're discussing). It's breathing in very diluted breath as you ride along, vs repeatedly breathing the same air they're breathing.

It also kinda hinges on how you think the rules are decided.

Either :
1) The somethingion of a number of risks to get us as close* to normal for most people as possible.

2) A line in the sand that says any activity that means you come within 1.99m of someone, or have a 1 in X thousand chance of ending up in A&E is banned.

It it's more the first one then you could make an argument for banning all sport regardless of low risk in favor of allowing people to see dying relatives and attend funerals (higher risk, but fewer people and arguably more necessary). Because overall the R number would be about the same.

*not necessarily very close


 
Posted : 26/05/2020 4:47 pm
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I’m just struggling to visualize how riding behind someone is greater exposure than say sitting 2m away facing them in a park. To give an analogy we can all relate to, you know how bad your BO is in the beer garden (2m social distanced) after an all day epic ride?

I don't mean following someone 20m behind on a descent, I'm talking about sitting on someone's back wheel on a climb. You're riding directly into whatever they've exhaled, and you could be sitting there for 10+ minutes at a time. So while it might be 'very diluted' breath, if you inhale 3L (approximate vital capacity) 30 times each minute for 10 minutes it's a significant exposure.

The 2m distance is based on droplet spread - the vast majority of any respiratory droplets hit the ground (due to gravity) within a 2m radius of you. Respiratory aerosols (NOT thought to be a major route of transmission in Coronavirus) and other molecules (E.g. smells) can travel a lot further than that 'on the breeze'. It's not the same thing. The question is whether the following rider will pass through the leader's 'cloud' (for want of a better word) of exhaled air before the droplets hit the ground. And if they're moving quickly I'm sure it's easily possible.

Again, I'm sure it's a very low risk activity but 1) I don't like the idea of people interpreting the rules however they like and 2) I worry about the 'optics' of riders wholesale ignoring advice because it suits them when others are making gargantuan efforts to stay away from others.


 
Posted : 26/05/2020 5:44 pm
 kcr
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... the transmission risk within a group of mountain bikers out for a ride on Sunday must be pretty small in the first place, no?

When I see groups out mountainbiking, they are often standing around in clusters chatting while regrouping after each stage of their run. I think organising any sort of group activity automatically increases the opportunities for inadvertent transmission, even if people think they are being careful.

I'm sticking to solo and household exercise for the forseeable future. I don't see any point in risking my own health or becoming a conduit for transferring the virus to other people.


 
Posted : 26/05/2020 7:09 pm
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The first part seems to be the actual definition of mountain biking or group riding? You sit behind or in front of someone for 5+ minutes… a very moderate 11.8 mph is 5ms-1 or you breath in what someone just breathed/coughed out a second ago if you keep 5m apart… or 2 seconds at 10m apart (etc.) obviously a fair bit of the time most of us are going at least double that speed… and group road riding ???

But you're not in static air - even if there's no wind there must be a shit-ton of turbulence created by someone's body as they ride. You might get a little bit of the same air but it's very very different to being inside a building sitting that close to someone.

This image of the turbulence behind a timetrialist
(image from https://link.springer.com/article/10.1007/s12283-017-0234-1)

That makes me doubt the simple cone shape shown - http://www.bikeirvine.org/news/2020/4/1/riding-in-the-time-of-covid-19
and also, mountain biking is a lot of more active and mobile than group road riding. You're not as close, your not following precisely the same lines, your body isn't in a static position, and our actual riding time tends to be far less.

Still agree, big groups a bad idea both optically and for maintaining distancing.


 
Posted : 26/05/2020 8:05 pm
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Study from Germany indicate that it is proximity, duration and indoor confinement that facilitate viral aerosol infection rates and represent high risk. Outdoor exposure risk is very low.

The fluid dynamics study images above is tosh, plausible tosh, but still unscientific and not peer reviewed.


 
Posted : 26/05/2020 8:13 pm
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One thing as I understand it from SARS-CoV-2, the actual virus that causes Covid-19 (the condition), is it's not a true airborne virus. In the air it is spread by water droplets and these fall to the ground rapidly. Hence the distance and that's to cover coughs and sneezes. Just being in the airstream of someone in front breathing doesn't mean you're exposed to water droplets containing the virus, not in sufficient quantities at least. Stood next to them chatting with spit and saliva coming out of their mouth for a few minutes and yes the risk is greatly increased.

Outdoors, sunlight, fresh air, can disperse and break up the virus as I understand it. In virus particle form it's quite vulnerable. The problem is once it hooks onto cells on the body.

Combine the outdoors risk with knowing who your riding buddies are and their activities. People you know who have basically been self isolating and solo riding for weeks. Chance of them being infected and actually infectious at the point of a ride is very low. Okay maybe they went to a shop the day before so risk there but still low chance with precautions.

If schools go back I'd be very wary about riding with anyone with kids though. Also those going back into offices. Schools and offices I still believe are the prime spread environments even if not everyone in them shows symptoms. That and airports and planes.

Of course if we could have an on demand test before a ride then we'd be clear to ride no worries. I'd be happy to pay for a test per ride if it wasn't stupid money.


 
Posted : 26/05/2020 11:03 pm
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Larry Lamb

Steve, all 4 nations are advised by the same group – SAGE. So again why has NI moved forward with larger group allowance than England. I’d also add that Outdoor markets will be allowed from the 1st June, thats certainly going to be a crowded affair.

You have to remember there are other factors here at play than just the science, like politics.

I agree with all that. The point is really that a political response it doesn't make it safe.
Objectively many other activities are less safe ... some we choose and others not but ultimately what makes an activity safe or not is how we manage it.

The vast majority of the population treat rules and advice as binary. Is group riding allowed... then it must be safe... Is tennis allowed... must be safe... they seem to require blanket statements.

Totally not cycling but the "school semi-official photographer" is doing a series of individual photo's they are going to merge together.
To make a consistent theme they are taking a cardboard box (75cm cubed) around 100+ kids houses over 2-3 days with an assurance "the box will be disinfected between kids".

I'm somewhat puzzled by how that is going to be achieved as it's not stated .... other than a huge energy source with UV B or microwaves how do you disinfect a cardboard box 100x without it getting soggy? Bleach? Soapy water? IPA?

I made my own box, we asked what the size was but of 100 other parents scheduled for the same day I don't think anyone else asked, they just "assume" as it say's "disinfected" (incl. the OH - "if she says its disinfected then we should just trust them and not ask how) ? I also know several of the families are meant to be self isolating due to symptoms... but as this is "in their own home (drive/garden) it's apparently OK"


 
Posted : 27/05/2020 10:29 am
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But you’re not in static air – even if there’s no wind there must be a shit-ton of turbulence created by someone’s body as they ride. You might get a little bit of the same air but it’s very very different to being inside a building sitting that close to someone.

Erm yes.... sitting inside a building the droplets fall to the ground faster than they spread an adequate viral load at 2m and if you are sitting in a room your not then in the same place as the other person 1/2s later.

Turbulence just keeps the droplets in the air... you can do this for yourself with a spray bottle and some light. If you want Febreeze or similar to settle quickly don't wave at it... let it fall of its own accord which takes a second or so after the initial energy and turbulence has worn off.


 
Posted : 27/05/2020 10:41 am
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Putting aside all the speculation about droplets for a moment, my feeling is that larger groups for socially responsible exercising could have been permitted by now - but the Gov't has been somewhat distracted by defending you know who.

The only new announcement I've seen is non-essential shops to re-open, which is great if you own a shop but is clearly an economically led measure and one which obviously seems less "safe" than group bike rides.

So while I'm still sticking to the guidelines, I no longer really resent others using their own initiative.


 
Posted : 27/05/2020 10:55 am
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