Helmet worked for me

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pjclinch
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Re: Helmet worked for me

Post by pjclinch »

Corpulent_Porpoise wrote: 12 Sep 2024, 9:40am
Read my previous post, I think it echoes what you both say to a degree. I don't swallow the hyperbole, never have, but I also know when it's obvious something has helped or hindered me.
What tends to be missing from these sorts of anecdote is the lack of parallel reasoning in other similar situations.

I know from banging my head that doing so on rocky roofs of caves in my caving helmet hurts a lot less than banging my head on e.g. half-down garage doors and kitchen cupboards when I'm not wearing my caving helmet... but I don't wear a caving helmet any time I go to a garage or a kitchen.
I know from dropping things on my toes barefoot or in sandals that it hurts a lot more than dropping stuff on my toes in my caving wellies or winter climbing boots, but I don't walk around most of the time in places I might drop something wearing my caving wellies or winter climbing boots.

So if you're riding in a place and a manner where head-butting a tree isn't too far off the probable events track it makes very good sense to wear one, but if it's a case of "I hit my head once and it hurt less with a helmet" isn't, of itself, much more of a reason to ride in a helmet than wearing safety boots around your house because you dropped a pan on your foot once or to rope up for stairs because you've fallen down them the odd time (vastly more people die from falls on stairs than in bike crashes, > 700/year compared to ~ 110, and yes, lots more people use stairs than ride bikes but on the other hand they don't generally use stairs for tens of minutes or hours at a time).

Speeding through close set trees, pushing your limits, strikes me as a pretty good place to wear a helmet. Because you hit your head once doing that isn't actually a slam-dunk logical reason to wear one to ride in a very different context. Not that I want to put anyone off wearing one if they want, but I would like more people to see it's more rationalisation than "common sense".

Pete.
Often seen riding a bike around Dundee...
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Cugel
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Re: Helmet worked for me

Post by Cugel »

pjclinch wrote: 13 Sep 2024, 9:01am
Corpulent_Porpoise wrote: 12 Sep 2024, 9:40am
Read my previous post, I think it echoes what you both say to a degree. I don't swallow the hyperbole, never have, but I also know when it's obvious something has helped or hindered me.
What tends to be missing from these sorts of anecdote is the lack of parallel reasoning in other similar situations.

I know from banging my head that doing so on rocky roofs of caves in my caving helmet hurts a lot less than banging my head on e.g. half-down garage doors and kitchen cupboards when I'm not wearing my caving helmet... but I don't wear a caving helmet any time I go to a garage or a kitchen.
I know from dropping things on my toes barefoot or in sandals that it hurts a lot more than dropping stuff on my toes in my caving wellies or winter climbing boots, but I don't walk around most of the time in places I might drop something wearing my caving wellies or winter climbing boots.

So if you're riding in a place and a manner where head-butting a tree isn't too far off the probable events track it makes very good sense to wear one, but if it's a case of "I hit my head once and it hurt less with a helmet" isn't, of itself, much more of a reason to ride in a helmet than wearing safety boots around your house because you dropped a pan on your foot once or to rope up for stairs because you've fallen down them the odd time (vastly more people die from falls on stairs than in bike crashes, > 700/year compared to ~ 110, and yes, lots more people use stairs than ride bikes but on the other hand they don't generally use stairs for tens of minutes or hours at a time).

Speeding through close set trees, pushing your limits, strikes me as a pretty good place to wear a helmet. Because you hit your head once doing that isn't actually a slam-dunk logical reason to wear one to ride in a very different context. Not that I want to put anyone off wearing one if they want, but I would like more people to see it's more rationalisation than "common sense".

Pete.
Quite so - common sense is a vastly over-rated facility not least because its rarely common and rarely sense. Its more usually an installed prejudice picked up from the surrounding culture (including the commercial culture of advertising, for us moderns) or a a wishful thunk that, "What I spent my money on, especially if it was a lot, is worth it".

But, as mentioned endlessly, even a polystyrene hat can sometimes reduce a headache. The only indication worth noting, post crash, is: did the polystyrene get completely crushed flat? A crack to the flimsy plastic skin, a little dent or a scrape, a big split but no squashed parts .... indicate only a tiny amount of force being absorbed. To offer protection, that polystyrene has to absorb energy by crushing from expanded to completely flattened, which by design absorbs 7Nm at best (probably less). This is rarely the case; but a crack or split looks so much more dramatic. "Saved my life, that crack!" No, it didnae.
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[XAP]Bob
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Re: Helmet worked for me

Post by [XAP]Bob »

Cugel wrote: 13 Sep 2024, 10:00amThe only indication worth noting, post crash, is: did the polystyrene get completely crushed flat? A crack to the flimsy plastic skin, a little dent or a scrape, a big split but no squashed parts .... indicate only a tiny amount of force being absorbed. To offer protection, that polystyrene has to absorb energy by crushing from expanded to completely flattened, which by design absorbs 7Nm at best (probably less). This is rarely the case; but a crack or split looks so much more dramatic. "Saved my life, that crack!" No, it didnae.
To be fair it doesn't need to be completely flat, but it does need to have suffered plastic deformation in a crush.
Brittle fracture is not an energy absorbing failure, though usually the plastic shell will retain the pieces to allow them to be crushed (so your hat can both suffer a brittle failure *and* do its job in an energy absorbing crush.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
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Steady rider
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Re: Helmet worked for me

Post by Steady rider »

No helmet -
How often will you crash - x
How often will you hit your head - y
How severe will be the impacts - z
How much rotation to the brain - w
Totals x+y+z+w

Helmeted
How often will you crash - a
How often will you hit your head / helmet - b
How severe will be the impacts - c
Will helmet use increase neck problems - d
How much rotation to the brain - e
assuming extra impacts, what long term consequences -f
Totals a+b+c+d+e

Answers to the two groups may help people assess helmets better.
maanderx
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Re: Helmet worked for me

Post by maanderx »

pjclinch wrote: 13 Sep 2024, 9:01am
What tends to be missing from these sorts of anecdote is the lack of parallel reasoning in other similar situations.
When people on bikes have accidents and they say that the helmet saved their life; surely they
would have had to have had an accident of the same or similar magnitude without a helmet to
make a truthful and accurate comparison.
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drossall
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Re: Helmet worked for me

Post by drossall »

Yes precisely. Part of the problem is that, if people wearing helmets have accidents and are unhurt, they credit the helmet. If they are hurt, they say that the helmet made it less serious.

Now those things could be true, but they are not evidence, because there is no situation that they would accept as evidence of the opposite.

And, of course, in club cycling in particular, people are beginning to forget that it is possible to ride without one, in part because everyone wears what the pros do. Once the alternative possibility is forgotten, it becomes not a sensible option - rather as, soon, a lot of people will forget that riding a non-e-bicycle is even an option, whatever the merits of electric assistance. Reasons why the other option might or might not be a good idea cease to be a serious part of the discussion.
ymfb
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Re: Helmet worked for me

Post by ymfb »

As the OP, I clarify and confirm the following as I’ve read some ridiculous claims, comments and assertions on this thread

I was riding very slow when I came off
I wasn’t on the drops
My helmeted head hit the road and sustained a crushed shell

It wasn’t an expensive helmet, it was replaced with a mid range MIPS type.

My riding style is not changed because I wear a helmet.

I don’t wear a helmet because others do, but as a piece of PPE exactly the same as other items worn at work.

As I’m sure I’ve stated before, if you choose not to wear a helmet, crack on, but don’t assume those of who do are less informed or ignorant.

The title of this thread is accurate and correct.

Ride safe
Two wheels preferred.
axel_knutt
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Re: Helmet worked for me

Post by axel_knutt »

..
Last edited by axel_knutt on 31 Oct 2024, 3:26pm, edited 1 time in total.
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Steady rider
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Re: Helmet worked for me

Post by Steady rider »

https://moose.co/products/kask-lifestyl ... pUQAvD_BwE
looks to weigh 390g

A broken chain may result in sudden movement, so controlling the bike is difficult. Head movement in controlling balance I gather can be a factor. Assuming a 5kg head mass, add 0.39, adding 7.8%. Avoiding falling by quickly adjusting, in part by moving the head, would likely be more difficult with a helmet. (ps some helmets weigh about 230g)

StClair and Chinn (2007) reported ‘
However, in both low speed linear impacts and the most severe oblique cases, linear and rotational accelerations may increase to levels correspond-ing to injury severities as high as AIS 2 or 3, at which a marginal increase (up to 1 AIS inter-val) in injury outcome may be expected for a helmeted head.
StClair VJ, Chinn BP, (2007) Transport Research Laboratory. Assessment of current bicycle helmets for the potential to cause rotational injury (trb.org) )Accessed 18/02/2022) https://trid.trb.org/view/810710

So, ymfb, you may be correct or incorrect in your view, you don't know if you would have fallen if not wearing the helmet, you don't know for sure if your head would have impacted the road, you don't know if the outcome was made worst. Assuming you are correct and it was of benefit.
Last edited by Steady rider on 13 Oct 2024, 9:01pm, edited 1 time in total.
Jdsk
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Re: Helmet worked for me

Post by Jdsk »

Steady rider wrote: 13 Oct 2024, 8:11pm StClair and Chinn (2007) reported ‘
However, in both low speed linear impacts and the most severe oblique cases, linear and rotational accelerations may increase to levels correspond-ing to injury severities as high as AIS 2 or 3, at which a marginal increase (up to 1 AIS inter-val) in injury outcome may be expected for a helmeted head.
StClair VJ, Chinn BP, (2007) Transport Research Laboratory. Assessment of current bicycle helmets for the potential to cause rotational injury (trb.org) )Accessed 18/02/2022) https://trid.trb.org/view/810710
There's a pretty low limit on how much evidence can be gathered from a single incident. But fortunately we already have much higher levels of evidence.

As repeatedly pointed out before that report is about how to improve the testing of helmets, not about the evidence of protective effects of helmets.

But if you want to try and use it to inform the discussion about protective effects here's what the authors say:
"Overall, it was concluded that for the majority of cases considered, the helmet can provide life saving protection during typical linear impacts and, in addition, the typical level of rotational acceleration observed using a helmeted headform would generally be no more injurious than expected for a bare human head."

Jonathan
Steady rider
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Re: Helmet worked for me

Post by Steady rider »

I would question the findings because low speed impacts may be fairly frequent.

Baschera et al 2021 study from Western Australia of 15yo+ cyclists, 2008-2015, who were admitted to the Royal Perth Hospital trauma unit found 88% of TBIs were mild among both helmet wearers and non-wearers, 3% were moderate among helmet wearers vs 10% among non-wearers, and 9% were severe among helmet wearers vs 2% among non-wearers. Among the 461 helmet wearers, 10 suffered severe TBI (2.16%). Among the 144 non-wearers, one suffered severe TBI (0.69%). The Baschera et al study shows 32.6% of non-helmet patients were affected by alcohol compared to 3.2% among helmeted cyclists, confirming other research showing significantly higher alcohol influence among injured non-helmet cyclists.

Other research shows a higher rate of severe for non-wearers. If Baschera had provided results comparing sober cyclists, that may have been worth knowing.
maanderx
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Re: Helmet worked for me

Post by maanderx »

I received a new MIPS accredited helmet today. In the small booklet that accompanied it, reads
the following:
A helmet reduces the risk of injury to the head but does not prevent serious injury or even deadly injury. It cannot guarantee protection against all types of knocks.
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Cowsham
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Re: Helmet worked for me

Post by Cowsham »

maanderx wrote: 14 Oct 2024, 7:08pm I received a new MIPS accredited helmet today. In the small booklet that accompanied it, reads
the following:
A helmet reduces the risk of injury to the head but does not prevent serious injury or even deadly injury. It cannot guarantee protection against all types of knocks.
Shows just where we're at with human intelligence that they have to print that on the instructions :lol: and some people think AI won't be smarter than us -- there's a good argument it already is.
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deeferdonk
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Re: Helmet worked for me

Post by deeferdonk »

The problem with someone posting I did/did not wear a helmet, had an accident and it worked for me, is that its it a bit of survivorship bias. There could be a hundred other people who had exactly the same incident/circumstances and are not posting because they are dead or in a coma!
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pjclinch
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Re: Helmet worked for me

Post by pjclinch »

Cowsham wrote: 16 Oct 2024, 6:15am
maanderx wrote: 14 Oct 2024, 7:08pm I received a new MIPS accredited helmet today. In the small booklet that accompanied it, reads
the following:
A helmet reduces the risk of injury to the head but does not prevent serious injury or even deadly injury. It cannot guarantee protection against all types of knocks.
Shows just where we're at with human intelligence that they have to print that on the instructions :lol: and some people think AI won't be smarter than us -- there's a good argument it already is.
People that think wearing a helmet equates to being safe really do exist.

Arriving at my kids' primary school for home-time pickup one day I was waiting with another parent that had a bike with them. One of the brakes was unhooked. I pointed it out, they said that they'd unhooked it because it was rubbing. I suggested that wasn't perhaps an optimally safe way to go about one's cycling but they said that it was okay because their child had a helmet.

Quite a lot of this seems to be a binary safe/dangerous attitude to risk underpinned by culture. There's a good piece on this cultural approach to safety at https://www.kaupunkifillari.fi/2019/03/ ... ng-safety/. Thing about culture is it provides quick default answers, so no actual thinking is necessary.

Pete.
Often seen riding a bike around Dundee...
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