Indie

Disclaimer: I'm not going to argue with anyone's personal choice, so don't jump on me for mine. I may remind my loved ones to wear seatbelts in cars, lifejackets on boats, and helmets on bikes, but I don't go crusading to random strangers about it.

Most of the anti-helmet sentiment I hear has to do with politics or fashion or comfort. As a former science major, I would like to hear some discussion of the actual physics. Is there any good science out there (not junk science from people with an agenda or a profit to make, but independent non-partisan science with the safety of riders in mind) that says wearing a helmet might be less safe than going without?

The human brain is fragile, and the skull can absorb some impact but not very much. It's easy to damage the brain badly with a surprisingly light impact. It's also easy to protect the brain from light impacts by putting shock-absorbing material around it. From a physics perspective, having that styrofoam shell around your head can mean the difference between brain injury and going home the same day instead of spending the night in a hospital.

That's what I'd like to debate -- can anyone point out the flaw in that argument, using physics (qualitative like mine, or quantitative; whichever you prefer)?

(As an aside: I understand that helmets aren't going to do much in heavier impacts, and aren't going to save me from neck or back injury. It's the more common light knocks to the head that can do a lot of damage without a helmet but are easily protected against with a helmet. Don't misrepresent the pro-helmet argument with that straw man; I don't think most helmet-wearers take unnecessary risks just because they're wearing helmets.)

For a secondary topic: materials science. I hear people complain that styrofoam isn't good enough for bike helmets, but I'm not so sure. The great thing about styrofoam is that it can absorb energy from lots of kinds of impacts -- it can crack or chip or compress, depending on what it's subject to. You want material that can absorb energy and take the damage itself, instead of rebounding into its original shape and passing the energy onwards into your head (or back outwards, making your head bounce on the pavement).

There might be some heavier materials that are better at absorbing energy, but the average rider might have neck problems if they wear something very heavy. There could also be a higher risk of heat exhaustion if you wear more material on your head. (If you can comfortably wear something like a military motorcycle helmet, and you feel safer that way, go for it.)

Okay, I'm done -- have at it.

ritepath

If you're only interested in protecting the top of the skull then a piece of foam is fine and dandy. If you're serious about protecting your jaw, ears and other components of your head you'd better look at a full face unit.

Like most of you I wear the "skull cap" type helmet mostly to set an example for my children. I've crashed a thousand and 41 times (If you ain't wreckin' you ain't ridin') and only recall once that the standard helmet would have made a difference, and that is enough for me to say "wear the helmet"

Bacciagalupe

There are all kinds of arguments pro and con. However, I don't think that studying it from a physics perspective is the way to go here. We don't understand brain injuries very well, minor injuries like concussions can wind up under-reported, and you could wind up with wildly different types of brain injuries, depending on point of contact and amount of force. In other words, too many variables and unknowns for a purely physics-oriented discussion to actually have much meaning.

That said, helmets do go through testing and need to meet certain standards. Unless you have some evidence that those standards are lacking, and while there is always room for improvement, I don't see any reason why the styrofoam should be insufficient to protect a head for most road uses, unless the helmet already had some impacts.

Ed in GA

I had a crash this last Sunday. I hit the ground pretty hard with the side of my head.

The unknown is what the result would have been had I not had a helmet on.

The known is that there was no result/injury and I got up and rode away.

Bicycle helmets may only be 15% effective in protecting the head in a crash. My wise old Dad used to say...

"15% of something is far better than 100% of nothing." I tend to agree with him.

My $ .02

Szczuldo

I don't see how there can be an argument against a helmet? Your brain is an important part of you and any measure taken to protect it should be. Wearing a good quality helmet adjusted properly..you WILL NOT feel it. If you buy cheap helmets, yeah you will be uncomfortable but that's what you get for being stingy. If you don't wear a helmet and you hit the ground with your head doing any sort of speed there is a good chance you will do some damage. With a helmet on and the way that you would most likely fall off your bike very little damage will be done to your head.

If your life isn't worth spending a 100$ on, then by all means continue to ride without a helmet. It's better that you get removed from the gene pool.

wahoonc

But what is the difference between a $15 helmet and $100 helmet? They are all "supposedly" built to one of 3 standards. And given the track record of stuff coming from China (where every helmet I have looked at is manufactured) ARE YOU SURE you are getting what you are paying for? Unless someone it testing them and reporting on them how are you going to know that the helmet you bought is actually going to do something?

Aaron

Bacciagalupe

More vents, that's about it. And what's the difference between a $30 handlebar and a $300 handlebar?


Yeah, pretty sure. QC is QC is QC, styrofoam is styrofoam, and it's not like American or Italian or Japanese companies were sprinkled with Magic Ethical Behavior Dust that makes their products better or perfect or whatever. In fact, it wasn't really all that long ago that the Brits looked on American products as unsafe, unscrupulously and cheaply manufactured....

P.S. I typically only drop $50 on a helmet.

uke

Style, vents, weight. And even then, the differences are slight. If your priority is safety, any helmet fitting the standards will do, which is the nice part of such an important investment; you really don't need to spend much to protect yourself. My helmet cost $30, and if I'd gotten the plain blue model, it would have cost 1/3rd less. I might buy a winter helmet for winter riding, and pay a little more there too to get the color I like.

It's hip to hate on China nowadays since we're really threatened by nations with large economies, but xenophobia aside, there's nothing that makes a Chinese-made product any less or more rigorous than a product made anywhere else. If the company you buy the product from doesn't invest in QC, the product will suffer regardless of where it's produced. This is what the corporate media leaves out when stirring up anti-Chinese FUD.

bmclaughlin807

Helmets are designed and tested to protect from one type of accident and ONLY one type of accident: Falling over sideways at 0 mph.

My issues with helmets include:

'Bike safety' consisting almost solely of "Always wear a helmet when you ride"... a bike helmet is absolutely the LEAST effective thing you can do to improve your safety on a bike... much more important are riding safely, wearing visible clothing, being aware of what's going on around you, proper lighting for conditions, properly maintained equipment. Heck, I even rate sunglasses as more important safety gear than a helmet.

Pro-helmet 'crusaders' that pretty much end up with the same argument "You're stupid for not wearing one"

Studies: I haven't seen a single study that was proven both pro-helmet AND unbiased... the studies that 'prove' their effectiveness were all either done by helmet manufacturers and used to attempt to pass mandatory helmet laws... (I wish that I could get a law passed that would make it mandatory that everyone in the country purchased a product I was selling.) or were SERIOUSLY flawed.

Helmets were introduced, designed, and are still tested to prevent serious injuries from falling over while riding... this is the type of accident most common in very unskilled riders (ie: children, mostly)... they're tested by putting a weight in them and dropping them straight down from a height of 6 feet.

The final issue is this: Bicycling is NOT DANGEROUS. People that insist that you HAVE to wear a helmet at all times fail to take this into account... The odds of dying from various complications of obesity are MUCH higher than the odds of getting killed while riding a bike.

If you make a habit of falling over and landing on your head, you SHOULD be wearing a helmet. If wearing a helmet makes you feel better about riding your bike, then, by all means, wear a helmet. But... DON'T CALL ME STUPID BECAUSE I CHOOSE NOT TO WEAR ONE! I'm quite smart enough to look at all the factors and decide that a helmet won't measurably improve my odds in the type of riding I do... what does improve my odds is defensive cycling... My driver's ed teacher told me that more than 90% of all accidents can be avoided by EITHER party involved... if only either one of them is really paying attention to what's going on around them... now THAT'S a safety improvement worth working towards, right?

El Pelon

I've ridden and raced both bicycles and motorcycles for years. Motorcycle helmets are also made of styrafoam and they do their intended jobs rather admirably.

The real problem with bicycle helmets is the overall lack of coverage. As a previous poster noted, the only comprehensive protection you can get is with a full face helmet, but these are totally impractical for road biking. (I, for one, would overheat and throw a rod after only about 2 miles.)

One area that needs to be examined, IMHO, is a brace to protect against compression damage to the neck. I wear a Leatt brace on my dirt bike, and feel pretty secure with it in place. It protects my neck from being squished like a beer can under foot.

Bacciagalupe

Since the goal is to test the ability of a helmet to disperse the force of an impact, and since there isn't much evidence I've seen (yet) that rotational injuries constitute a serious threat or major category of injury for cyclists, I'm not exactly sure what fault you're finding with the tests.


Sorry, but that's a straw-man argument. I can't think of a single reputable source that claims that the only thing you need to do is wear a helmet.


New York City's study of 9 years of cycling fatalities and injuries showed that helmets were not worn in an extremely high percentage of bicycle fatalities (97% where helmet use is known). The study was not done by helmet manufacturers and did not recommend mandatory helmet use for adults. So here's your "single study."

https://www.nyc.gov/html/doh/download...ike-report.pdf

By the way, since scores of government agencies, universities and medical journals do research -- and they are not all uniformly insisting to the nth degree that helmets should be mandatory for adults -- I'm finding a little bit implausible that they are all compromised by some sort of nefarious bicycle helmet lobby....



Actually, I for one feel quite comfortable in saying that cycling is generally safe and that wearing a helmet reduces the risk involved in the event that you crash. Much in the same way that driving is generally safe and wearing a seatbelt will reduce the risk of serious injury or death if you happen to get into an accident.

Since the economic and comfort costs of wearing a helmet are negligible, I can't really think of a reason not to wear a helmet most of the time, especially in dense urban environments.

RobertHurst

Hey, your approach to this issue is reasonable and therefore a breath of fresh air.

There isn't much quantitative research on impacts with helmets. But here's some food for thought. Many of the impacts suffered by helmet wearers (how many impacts? I don't know) occur _because_ they are wearing helmets. That is, the extra volume of the helmet makes the "head" significantly larger than it would be otherwise, making it far more likely that there will be some sort of smack! when you fall off the bike. It's possible to have a significant smack! when wearing a helmet that wouldn't occur at all without a helmet -- the extra volume is that important. Most helmet wearers don't consider this at all and many become quite agitated at the mere suggestion.

Also, helmets should be considered as a compromise between style, weight, ventilation and safety. Safety kind of takes a back seat to the other things with bike helmets. The aero look of helmets is important for marketing purposes but many believe the oblong shape, and the vents, could be a serious liability in a bad wreck. The worst head injury you can get is one in which the neck is twisted violently, causing tearing of blood vessels at the base of the brain. That's deadly. Would be much better to crack your skull open than twist your neck like that. If the misguided marketing-oriented shape of bike helmets contributes to these injuries that might help explain why results are so disappointing when studying the effectiveness of helmets over whole populations.

Robert

RobertHurst

If you hit the ground at a speed above 14 mph, then the standards are lacking.

xenologer

see below
Maybe it's just that I have good reflexes?
But I've gone over the handlebars twice at about 10-15mph(one onroad when my wheel brushed another rider, one offroad going downhill thru gravel),
and a few 0mph flop overs from when I was learning to ride.
But in all these cases I've never worn a helmet, and in all cases my head has never once touched the ground.
(its kinda odd, I have a tendancy to roll and land in a sitting position looking like nothing happened...)

So there may be something to Rob's suggestion that a helmet both makes your head a bigger target to bang up (as well as makes it heavy and more likely to flop around before you catch yourself.)
Perhaps having my head uncovered means my sense of sight and balance are less encumbered and allows me to react faster?
One of the mechanics at local bike co-op claims he doesn't wear one in part because of the lessened visibility/awareness making traffic more of a risk... so that kinda fits too...

Wanderer

I also ride a motorcycle , a lot, have several helmets, and usually opt for the full facer.

The way I look at it is this.

If you hurt your arm, leg, foot, or hand - really bad - they can cut it off and you can still live to a ripe old age, and still function in society. You still have other appendages to help you get along.

YOU ONLY GET ONE HEAD!

I'm going to do anything I can to help me survive an accident.

Even bicycle helmets, beanies or not, offer me a lot of protection, for a minimal discomfort.

It's a no brainer, as far as I'm concerned.

BarracksSi

Besides the vents, lighter weight, etc, I'm beginning to think that the construction methods used in higher-priced helmets can actually make them safer (thanks to a few stories here on BF). The idea is that molded-in-shell helmets stay together better than helmets with only a taped-on shell, and are able to give some level of protection for the second or third impact in a crash.

Yeah, I know that the taped-shell helmets meet the same safety standards, but I also think that the standards might not be good enough.

bmclaughlin807

For one, there is NOTHING in that study that either proves or even seriously looks at the actual effectiveness of helmets in preventing injury... and several things that point out how much the information can be (is?) skewed by other factors:

Quotes from your pdf:


My take on the 'study':
It would appear that other risk factors are probably MUCH more likely to influence the chance of being involved in a fatal crash than whether or not you wear a helmet... Just look at the HUGE difference in death rates between male and female riders...

The rather alarming looking quote about 97% of bicyclists involved in fatal accidents not wearing helmets? Oh, wait.. that was 97% of 59% of the accidents... the other 41% they didn't record whether the cyclist was or wasn't wearing a helmet... maybe because they were and the person filing the report didn't feel it necessary to add that detail? (Yeah, helmets don't help much if you get run over by a dump truck, do they???) If we assume that the other riders were all wearing helmets (Hey, that's as valid as assuming they weren't, or that the percentages were exactly the same as for the group that WAS recorded, right?) Then you come out with 57%...

But now that you mention it... EVERY case I can remember where a cyclist death made all the news the cyclist WAS wearing a helmet or was involved in an accident where a helmet would have had no influence at all on the outcome.

Oh... and the bit that I highlighted about NONE of the child and teen riders who died were wearing helmets? Well... that's highlighted for 2 reasons: 1) This is the group of people that helmets were truly designed to help, and 2) they were already breaking the law by riding without a helmet... exactly the same people that might engage in risky behavior while riding?

Oh... and here's another interesting statistic: Pedestrians accounted for less than 4 times as many people, but over 8 times as many fatalities... you're more than twice as likely to get killed WALKING as cycling... where are the helmet advocates for the pedestrians? Body armor, anyone?

So... anyone have an actual helmet study that shows anything useful?

dbostrom

A simple little bit of legal language, tattooed (or maybe printed on paper and held on w/a rubber band, but judging from comments perhaps that would be too heavy/confining/hair-mussing/uncool/noncontrarian) in place of a helmet, stating that in the event of a injury to optionally protected portions of the skull the non-helmet wearing cyclist absolves their insurer, relatives, the government and all other parties thus suffering from transference of risk of any financial obligation for attempts at cranial repair, cognitive rehabilitation or lifelong maintenance in the head-of-lettuce-condition?

Certainly we should have choices in matter such as this, just as we should be allowed assisted suicide, etc. Similarly the borders of responsibility arising from personal choices could be drawn with reasonable clarity.

Of course, in cases of the truly psychotic, such as we see in cases where it is claimed that helmets are somehow of no benefit, it is questionable whether such a waiver would really hold water. Perhaps a psychiatric examination prior to application of the tattoo would be a necessary part of the equation. I believe assisted suicide laws also recognize this possibility.

RobertHurst

Fine -- then, after that, the govt. goons can head over to your house and check your cupboards and fridge for illegal junk food products, check your bodily fluids and make certain that you and the whole family are adhering to your government-administered exercise program.

In truth, the helmeted cyclist and non-helmeted cyclist both save society money. Although it is canceled out a bit in the end by their extra longevity.

CB HI

Remember the old styrofoam only helmets. The ones without a plastic shell on the outside of them. They were as dangerous, if not more dangerous than no helmet. They passed the impact test just fine. They were not tested for other possible injury mechanisms though.

The problem was that when a cyclist went down at speed, the helmet protected the head from the impact, but without the plastic shell, the higher coefficient of friction of the styrofoam would cause the helmet to sort of stick to the road (drag on the road slower than your body). The sudden speed difference between your head and your body placed high stresses on your neck (neck strains - all the way up to a possible broken neck).

CB HI

Actually, I thought some of the data indicated that the extra longevity of cyclist cost society more money in sum total. Just don't let motorist and law makers know it, otherwise they will want to start charging cyclist a longevity tax in lieu of gas taxes.

StrangeWill

Yup, reoccurring theme in just about... anything with a statistic, there is always someone to doubt it, and claim they know better.


Not that I'm saying you're dumb, you're just a statistic as far as statistic arguments go.

Pedaleur

However, in the subgroup (one particular year), there were much better records (a much higher % of reported use/non-use of a helmet), and the statistics were the same. This indicates that the reported cases are a decent representative of the complete picture. To go off on a wild "What if?" tirade is a bit useless.

Wait, what? You're saying that there are only four times as many pedestrians as cyclists? Where is that from? This study? Another? That seems very low.

---

The big issue with the NYC study is that the helmet use of the general population isn't known. All I saw was a study asking high-schoolers if they had used a helmet in the past year _at least once_. This does very little to tell us the overall rate of helmet use, which is necessary to determine the significance of the fact the 97% of the people killed weren't wearing helmets. (In fact, with 14-20% answering "yes", and knowing that 'once' is a far cry from usually/always, it suggests that overall helmet use is very low. I'd be happy to hear if I missed something.

chipcom 

I'm curious, if you are comfortable with your choice to wear a helmet and claim that you don't want to go on a crusade, why would you go out of your way to start a thread with the express purpose of debating the merits of wearing a helmet...scientific or not?

It's pretty much a no-brainer that having a helmet on when your head hits the ground is probably better than nothing at all...the potential benefits of a helmet are not a point of contention to either 'side'. Indeed, I can't recall one single (non-tongue-in-cheek) post in BF advocating NOT wearing a helmet, thus I'm not sure who these 'anti-helmet' people are. To me starting this thread is just another troll, despite the protestations outlined in the OP.

If you truly want to know about the physics of helmets, there is already a sticky were a lot of people have gone to great lengths to post study upon study and debate the actual merits of helmets (in between the usual sniping and foolishness of folks like me).

tntyz

Could someone please point me to the study that shows wearing helmets has either caused more injuries or increased their severity?

As far as the type of fall that helmets protect in . . . I just got into clipless pedals and am still learning how to disengage quickly. And yes, I DO spend quite a bit of time on a trainer with them to practive getting out of them.