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#141
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Can't Use Helmets in the Sun????
GaryG wrote:
By that "rationale", a cotton cycling cap would confer a greater degree of protection than a proper cycling helmet. Not sure if that's the argument you're trying to make, but that's the take-home message. It depends on the accident. If the accident is one where a capped head comes within an inch of an obstacle but a helmeted head hits it, then that would indeed be the case. Another possibility is that a capped head ends up concussed and grazed but a helmeted head is twisted by the extra leverage allowed by the helmet and has its neck broken. But you don't know if that would be the case up front, of course... The take-home message is you cannot say for sure that after an accident you were *surely* better off with a helmet, simply on the grounds that it hit something. You might be, but you won't /definetly/ be. FWIW, the average human head weighs between 4.5 and 5 kg. An average bicycle helmet (e.g., Gyro Pneumo) weighs 0.26 kg, so the average increase in head weight is around 5%. You've implied in quite a few posts that an unhelmeted cyclist can keep their head from impacting the ground in a fall by use of their neck muscles, and you've also stated that a helmeted cyclist's neck muscles would not be able to overcome the additional momentum of the helmet. Given the small additional mass of a modern helmet, I strongly suspect your argument is specious (a nice way of saying you're pulling it out of your ass). It's not just weight, it's size too. You'd have an easier job keeping an unhelmeted head off the deck than a zero weight helmet because you don't have to keep it up the extra distance required by the additional size of the helmet. The head is kept up by reflex action, and the reflexes are working on a self-knowledge of where the head is and extends to. Unless you make a habit of sliding around tarmac in a cycle helmet then the reflex to keep the head up is using information on the head, not the helmeted head. This is quite easy to see safely in practice: wear a helmet in a cave and you'll bang your head far more often than if you don't (though in this case since you'll almost certainly be banging it anyway, and are never above walking pace, it's definitely worth wearing!). Yet again the clear message is that "helmets are dangerous". No, it is that they are *potentially* dangerous and are *not* a clear win. Do you have any studies to back up your rather bizarre assertions that helmets increase the dangers of head impact/neck injuries? Or, is this merely yet more of your anti-helmet crusade? Go to www.cyclehelmets.org and get reading. For example, you can find one that suggests you're 7 times more likely to hit your head in a crash with a helmet than without in Wasserman RC, Waller JA, Monty MJ, Emery AB, Robinson DR. Bicyclists, helmets and head injuries: a rider-based study of helmet use and effectiveness. 1988. American Journal of Public Health: 1988 Sep;78(9):1220-1 Not a study, but an expert opinion you'll find there is, "the very eminent QC under whose instruction I was privileged to work, tried repeatedly to persuade the equally eminent neurosurgeons acting for either side, and the technical expert, to state that one must be safer wearing a helmet than without. All three refused to so do, stating that they had seen severe brain damage and fatal injury both with and without cycle helmets being worn. In their view, the performance of cycle helmets is much too complex a subject for such a sweeping claim to be made." It isn't an anti-helmet crusade, it's a get real about the realities of what you can really expect crusade. If I was "anti helmet" I wouldn't own and occasionally wear one. Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
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#142
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Can't Use Helmets in the Sun????
"Peter Clinch" wrote in message
... GaryG wrote: By that "rationale", a cotton cycling cap would confer a greater degree of protection than a proper cycling helmet. Not sure if that's the argument you're trying to make, but that's the take-home message. It depends on the accident. If the accident is one where a capped head comes within an inch of an obstacle but a helmeted head hits it, then that would indeed be the case. Another possibility is that a capped head ends up concussed and grazed but a helmeted head is twisted by the extra leverage allowed by the helmet and has its neck broken. But you don't know if that would be the case up front, of course... The take-home message is you cannot say for sure that after an accident you were *surely* better off with a helmet, simply on the grounds that it hit something. You might be, but you won't /definetly/ be. FWIW, the average human head weighs between 4.5 and 5 kg. An average bicycle helmet (e.g., Gyro Pneumo) weighs 0.26 kg, so the average increase in head weight is around 5%. You've implied in quite a few posts that an unhelmeted cyclist can keep their head from impacting the ground in a fall by use of their neck muscles, and you've also stated that a helmeted cyclist's neck muscles would not be able to overcome the additional momentum of the helmet. Given the small additional mass of a modern helmet, I strongly suspect your argument is specious (a nice way of saying you're pulling it out of your ass). It's not just weight, it's size too. You'd have an easier job keeping an unhelmeted head off the deck than a zero weight helmet because you don't have to keep it up the extra distance required by the additional size of the helmet. The head is kept up by reflex action, and the reflexes are working on a self-knowledge of where the head is and extends to. Unless you make a habit of sliding around tarmac in a cycle helmet then the reflex to keep the head up is using information on the head, not the helmeted head. The reflex to keep one's head off the deck does not concern itself with an extra 2 cm of radius...it's a neuromuscular response, and the response is to keep the head up as much as possible, regardless of size or headgear. To imply that a helmeted head will smack the ground with force, because one's reflexive reaction to an impending impact miscalculated the additional effective head size occasioned by the helmet is simply ludicrous. This is quite easy to see safely in practice: wear a helmet in a cave and you'll bang your head far more often than if you don't (though in this case since you'll almost certainly be banging it anyway, and are never above walking pace, it's definitely worth wearing!). True perhaps, but that's not at all the same as the reflexive reactions to protect one's skull that occur during falls. Yet again the clear message is that "helmets are dangerous". No, it is that they are *potentially* dangerous and are *not* a clear win. Do you have any studies to back up your rather bizarre assertions that helmets increase the dangers of head impact/neck injuries? Or, is this merely yet more of your anti-helmet crusade? Go to www.cyclehelmets.org and get reading. For example, you can find one that suggests you're 7 times more likely to hit your head in a crash with a helmet than without in Wasserman RC, Waller JA, Monty MJ, Emery AB, Robinson DR. Bicyclists, helmets and head injuries: a rider-based study of helmet use and effectiveness. 1988. American Journal of Public Health: 1988 Sep;78(9):1220-1 Not a study, but an expert opinion you'll find there is, "the very eminent QC under whose instruction I was privileged to work, tried repeatedly to persuade the equally eminent neurosurgeons acting for either side, and the technical expert, to state that one must be safer wearing a helmet than without. All three refused to so do, stating that they had seen severe brain damage and fatal injury both with and without cycle helmets being worn. In their view, the performance of cycle helmets is much too complex a subject for such a sweeping claim to be made." It isn't an anti-helmet crusade, it's a get real about the realities of what you can really expect crusade. If I was "anti helmet" I wouldn't own and occasionally wear one. Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#143
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Can't Use Helmets in the Sun????
GaryG wrote:
The reflex to keep one's head off the deck does not concern itself with an extra 2 cm of radius...it's a neuromuscular response, and the response is to keep the head up as much as possible, regardless of size or headgear. Quite so, but the muscles and overall physiology and what is needed to keep one's head safe (and thus capable of passing one's genes on) is supported by several million years of evolution of not being bigger than it is, which isn't the case with heads in helmets (i.e., if the head needed picking up more than it does there may have been reasons to evolve more effective means of doing so, but you won't develop such mechanisms just for the sake of it). As the publication I pointed to suggests, there *is* evidence that you're considerably more likely to hit your head, however "ludicrous" what I happen to be saying. Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#144
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Can't Use Helmets in the Sun????
Peter Clinch wrote:
GaryG wrote: The reflex to keep one's head off the deck does not concern itself with an extra 2 cm of radius...it's a neuromuscular response, and the response is to keep the head up as much as possible, regardless of size or headgear. Quite so, but the muscles and overall physiology and what is needed to keep one's head safe (and thus capable of passing one's genes on) is supported by several million years of evolution of not being bigger than it is, which isn't the case with heads in helmets (i.e., if the head needed picking up more than it does there may have been reasons to evolve more effective means of doing so, but you won't develop such mechanisms just for the sake of it). So the more we wear helmets the safer we'll be, evolution-wise. LOL |
#145
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Can't Use Helmets in the Sun????
Sorni wrote:
So the more we wear helmets the safer we'll be, evolution-wise. LOL In the long term if wearing them enhances your ability to both reproduce and be safe, probably... I'll freely admit I wasn't too coherent in my arguments here, let's try again: It is natural to try and keep your head away from impacts by reflex. Reflex action will try and keep your head as far away fromn the deck as possible. It does not always succeed, therefore there are times when the muscles cannot keep the head off the deck. Those situations are more likely to crop up with a bigger and heavier head. In any given crash, a bigger and heavier head is more likely to take a hit than an otherwise smaller and lighter one. How's that? Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#146
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Can't Use Helmets in the Sun????
"Peter Clinch" wrote in message
... Sorni wrote: So the more we wear helmets the safer we'll be, evolution-wise. LOL In the long term if wearing them enhances your ability to both reproduce and be safe, probably... I'll freely admit I wasn't too coherent in my arguments here, let's try again: It is natural to try and keep your head away from impacts by reflex. Reflex action will try and keep your head as far away fromn the deck as possible. It does not always succeed, therefore there are times when the muscles cannot keep the head off the deck. Those situations are more likely to crop up with a bigger and heavier head. In any given crash, a bigger and heavier head is more likely to take a hit than an otherwise smaller and lighter one. How's that? If helmets were 1 meter in diameter, and made out of stainless steel, you might have an argument. But given that helmets only add about 2 cm of radius and 5% additional mass, I still think your arguments in this regard have no merit whatsoever...they are, at best, mere speculation with nothing whatsoever to back them up. Nevertheless, if my reflexes fail to keep my head from hitting the ground in a fall (due to the type of fall, the force or angle of the fall, etc.), I'd much rather have a helmet absorb the initial impact instead of my unprotected scalp. GG Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#147
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Can't Use Helmets in the Sun????
GaryG wrote:
"Peter Clinch" wrote in message ... Sorni wrote: So the more we wear helmets the safer we'll be, evolution-wise. LOL In the long term if wearing them enhances your ability to both reproduce and be safe, probably... I'll freely admit I wasn't too coherent in my arguments here, let's try again: It is natural to try and keep your head away from impacts by reflex. Reflex action will try and keep your head as far away fromn the deck as possible. It does not always succeed, therefore there are times when the muscles cannot keep the head off the deck. Those situations are more likely to crop up with a bigger and heavier head. In any given crash, a bigger and heavier head is more likely to take a hit than an otherwise smaller and lighter one. How's that? If helmets were 1 meter in diameter, and made out of stainless steel, you might have an argument. But given that helmets only add about 2 cm of radius and 5% additional mass, I still think your arguments in this regard have no merit whatsoever...they are, at best, mere speculation with nothing whatsoever to back them up. Nevertheless, if my reflexes fail to keep my head from hitting the ground in a fall (due to the type of fall, the force or angle of the fall, etc.), I'd much rather have a helmet absorb the initial impact instead of my unprotected scalp. GG Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ WTF? Cross-posting to rec.bicycles.marketplace?!? Aren't you worried about all the other potentially fatal wounds you might receive in an accident? How do those risks compare to those from head injuries? Robin Hubert |
#148
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Can't Use Helmets in the Sun????
In article ,
"GaryG" wrote: "Peter Clinch" wrote in message ... It is natural to try and keep your head away from impacts by reflex. Reflex action will try and keep your head as far away fromn the deck as possible. It does not always succeed, therefore there are times when the muscles cannot keep the head off the deck. Those situations are more likely to crop up with a bigger and heavier head. In any given crash, a bigger and heavier head is more likely to take a hit than an otherwise smaller and lighter one. How's that? If helmets were 1 meter in diameter, and made out of stainless steel, you might have an argument. But given that helmets only add about 2 cm of radius and 5% additional mass, I still think your arguments in this regard have no merit whatsoever...they are, at best, mere speculation with nothing whatsoever to back them up. I wear a hard hat, and always clank it into stuff. I will say to myself, "Self, you are wearing a hard hat. Watch your step." For a while that works, then I stop devoting attention to such a ridiculous thought: that my head is bigger than it is. Ludicrous. Then Blam! I smacked it into something again. I have been wearing eyeglasses for decades, and still knock theem off in close quarters. We really have hardwired into us how big our head is. Even a billed cap is knocked askew, as often as not. Nevertheless, if my reflexes fail to keep my head from hitting the ground in a fall (due to the type of fall, the force or angle of the fall, etc.), I'd much rather have a helmet absorb the initial impact instead of my unprotected scalp. If I had not been wearing that impossible hard hat, I would never have knocked it or my head into solid objects. Noone will mistake me for Mikhail Baryshnikov, yet I do not smack my unadorned head into solid objects; not at all. -- Michael Press |
#149
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Can't Use Helmets in the Sun????
GaryG wrote:
If helmets were 1 meter in diameter, and made out of stainless steel, you might have an argument. But given that helmets only add about 2 cm of radius and 5% additional mass, I still think your arguments in this regard have no merit whatsoever... Bigger is bigger is bigger. It is hard to keep something bigger from hitting the deck given the same support. are, at best, mere speculation with nothing whatsoever to back them up. It's hardly "mere speculation" that bigger targets are easier to hit. What about the paper I suggested? Nevertheless, if my reflexes fail to keep my head from hitting the ground in a fall (due to the type of fall, the force or angle of the fall, etc.), I'd much rather have a helmet absorb the initial impact instead of my unprotected scalp. Fine, but that's not the point at hand. Yes, if someone whacks me over the head with a baseball bat I'd sooner be wearing a helmet than a cycling cap. But if the bat is swung vigorously 1cm away from my head then the fact is the helmet /then/ makes me worse off. Which it wouldn't do if it was /only/ ever a benefit or totally irrelevant. Thus, you cannot say for /sure/ that in an accident you must be better off with a helmet. Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#150
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Can't Use Helmets in the Sun????
Peter Clinch wrote:
Bigger is bigger is bigger. It is hard to keep something bigger from hitting the deck given the same support. typo time That should be hard/er/, rather than just hard /typo time Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
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