Strategy Trade and List management Thread Part 5 (opposition supporters - READ posting rules before posting)

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I know very little about the topic, so apologies if this is a very ignorant (not to mention rambling) question. (Not specifically directed at you either, but your post got me thinking.)

If concussion results primarily from the impact of the brain on the inside of the skull, this is presumably a result of a sudden change of direction, right? For instance, the head was moving at a certain speed in one direction, but then as a result of an impact (e.g., with a player, or the ground), the skull moves in a new direction (or stops altogether) while momentum leads the brain to continue in its initial direction until it impacts the skull. Is this the idea?

In that case, why do we only see concussion following direct impacts to the head, rather than body hits or tackles where a player is slung to the ground without direct impact to the skull? These also cause sudden directional changes. Is it simply that the mechanics of the human body mean that the changes are less severe away from the point of impact (e.g., the head gradually sways when the body is hit—sort of like rebounding at the end of a bungee jump)?

If it’s the case that less severe directional changes resulting from indirect impacts reduce the probability of concussion, then would the same not also be true if players were to wear heavily padded helmets (i.e., not rigid ones as are worn in American or Canadian Football, but something a lot more... foamy)? Is it just that obtaining a gain sufficient enough to make a noticeable difference concussion-wise would require helmets that are so large as to be impractical?
Disclaimer: I am not a biomechanist but I am involved in fields relevant to concussion and have worked in the area previously.

The "brain against skull impact" account of concussions is outdated and only one possible cause (of both concussion and more significant Traumatic Brain Injury). More contemporary accounts talk about the contortion of the brain relative to itself. The brain isn't rock solid and is quite malleable, so not all of the brain responds to the force exactly the same - some parts go slower, some parts go faster, and some parts go in slightly different directions. This causes "tearing" (or shearing injuries as we call them) of the delicate tissue as the neurons are stretched and snapped. With current imaging technology these injuries don't often show up, and we are recognising more and more that this is the actual threat in more cases.

The reason it occurs typically following impact is because the rapid deceleration caused by impact exposes the body (and, by extension, the brain) to a huge amount of force over a very short period of time. This is far beyond the amount of force you are exposed to by simply being thrown to the ground. Think about whiplash injuries from car accidents - it's not the fast driving that causes it, it's the point of impact that throws your body around.

Helmets do not work for concussion because they don't slow the deceleration to enough of an extent to prevent this shearing (or, in some cases, actual skull-brain contact). With or without the helmets, you won't stop the brain from contorting, you'll just soften the blow to your skull. As far as I'm aware there is no current headgear technology that has been proven to reduce the risk of concussion. Perhaps you're right that they would need to be impractical to actually be effective - as of now, to my knowledge nobody has managed to figure out any feasible methods by which to reduce the risk to the brain.

The head of AFL concussion research, A/Prof Cathy Willmott, has some interesting research in this area if anybody is that way inclined.
 
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I’d be looking at the following players:
Tom Fullerton
Jackson Payne
Jeremy McGovern
Josh Treacy
Hayden Mclean
Joel Amartey
Fischer McAsey (if really cheap)
Josh Worrell
Keiran Strachan
 
Helmets do not work for concussion because they don't slow the deceleration. With or without the helmets, you won't stop the brain from contorting, you'll just soften the blow to your skull. There is no current headgear technology that has been proven to reduce the level of force the brain is exposed to. Perhaps you're right that they would need to be impractical to actually be effective - as of now, to my knowledge nobody has managed to figure out any feasible methods by which to reduce the risk to the brain.

The head of AFL concussion research, A/Prof Cathy Willmott, has some interesting research in this area if anybody is that way inclined.
I've always been confused by this claim. I understand the mechanism of concussion being due to the brain impacting on the skull, and they might not make a significant difference to the concussion outcome, but surely a soft helmet at least must slow the deceleration somewhat as the padding transfers the impact - similar to a crumple zone in a car?
 
I've always been confused by this claim. I understand the mechanism of concussion being due to the brain impacting on the skull, and they might not make a significant difference to the concussion outcome, but surely a soft helmet at least must slow the deceleration somewhat as the padding transfers the impact - similar to a crumple zone in a car?
This is more of a physics/biomechanics question than it is my area, so I can't give as comprehensive an answer as I'd like to. It is a complex area but my understanding is that they slow the linear deceleration, but struggle more to hinder rotational deceleration, which is often less significant in car accidents. Nevertheless, consider that (1) the crumple zone is much, much larger on vehicles than the tiny amount of padding on soft-shelled headgear; and (2) the crumple zone certainly does reduce the force, but despite this you still get cases of significant whiplash, even from braking rather than actual impact. So, in short, you are correct that my post should really be more nuanced - they likely do slow the deceleration somewhat, but there is no evidence that they do this to the extent that they change concussion outcomes at present.

As an aside, a bigger problem is that there are at present (or at least as of a couple years ago) no official manufacturing guidelines for creating effective and up-to-scratch headgear - so much of what is on the market (I'm looking at you, Rebel) is just pure s**t with no real engineering nuance or scientific merit.

Ps: as I mentioned, the brain hitting the skull isn't necessarily considered the key mechanism anymore ;)
 
Disclaimer: I am not a biomechanist but I am involved in fields relevant to concussion and have worked in the area previously.

The "brain against skull impact" account of concussions is outdated and only one possible cause (of both concussion and more significant Traumatic Brain Injury). More contemporary accounts talk about the contortion of the brain relative to itself. The brain isn't rock solid and is quite malleable, so not all of the brain responds to the force exactly the same - some parts go slower, some parts go faster, and some parts go in slightly different directions. This causes "tearing" (or shearing injuries as we call them) of the delicate tissue as the neurons are stretched and snapped. With current imaging technology these injuries don't often show up, and we are recognising more and more that this is the actual threat in more cases.

The reason it occurs typically following impact is because the rapid deceleration caused by impact exposes the body (and, by extension, the brain) to a huge amount of force over a very short period of time. This is far beyond the amount of force you are exposed to by simply being thrown to the ground. Think about whiplash injuries from car accidents - it's not the fast driving that causes it, it's the point of impact that throws your body around.

Helmets do not work for concussion because they don't slow the deceleration to enough of an extent to prevent this shearing (or, in some cases, actual skull-brain contact). With or without the helmets, you won't stop the brain from contorting, you'll just soften the blow to your skull. As far as I'm aware there is no current headgear technology that has been proven to reduce the risk of concussion. Perhaps you're right that they would need to be impractical to actually be effective - as of now, to my knowledge nobody has managed to figure out any feasible methods by which to reduce the risk to the brain.

The head of AFL concussion research, A/Prof Cathy Willmott, has some interesting research in this area if anybody is that way inclined.
What if the helmet had Springs on it?
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Might be controversial but I'm not offering Dunkley huge money. If he wants to go for a large term deal let him go.

I have all the faith that someone like West/Garcia when given the opportunity could offer 80% of what dunkley can do when they get to there prime.

We should be building around generation talents at the club. I'd rather Lose Dunkley and offer Naughton a market rate deal when he comes out of contract in 2024 rather than risk any chance of losing him.

Personally i'd plan to have 1.1-1.3 million of space to make sure Naughts is a life long bulldog. We have lost mids like Dunkley before and come out of the other side. If we can keep dunks and our essential players great. If there is any risk though I'd leave Dunks open to losing him rather than losing our biggest assets.
 
I’d give Dunkley and our first for Gibcus but Richmond would never agree to it.

Gibcus is going to be an absolute gun.
Way overs surely. Gibcus was pick 9 and he’s done well but not Dunkley plus pick 9 (based on current ladder position) level.

Mitch Cleary on 7news reporting Hannan and Buku re-signed on one year deals. Hannan to return in the next few weeks as well.
I hope this isn’t true. Why are we offering Hannan an extension before checking he can recover and play good football. We’re not at risk of losing him to another team.
 
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Way overs surely. Gibcus was pick 9 and he’s done well but not Dunkley plus pick 9 (based on current ladder position) level.


I hope this isn’t true. Why are we offering Hannan an extension before checking he can recover and play good football. We’re not at risk of losing him to another team.

The deal is only for one year. We need some squad players. Can’t have a list full of best 22.
 
The deal is only for one year. We need some squad players. Can’t have a list full of best 22.
Not much use as squad depth if he can’t properly recover. I’m not opposed to the concept of him being on the list in 2023, I’m just saying why does he need to be locked away now versus at the end of the year.
 
Dunkley is a must keep. People on this forum underestimating his importance for us going forward both as a successor to Libba who doesn’t have much left in the tank and as a leader at the club.

I think people lost some emotional attachment to him after the Essendon saga which is understandable but a big takeaway from that personally was that he’s highly ambitious and a Puritan when it comes to professionalism. God knows we need as much of that at the club as possible.

Suggestions that a kid like West can step straight into replacing Libba might not be too far off the mark in terms of playing style but in terms of the on field maturity and leadership personally I think West is still a long way off.

From my perspective the lack of mature leadership in all areas of the ground was our number one issue post 2016 and I would hope we’ve learned from that over the past 5 years.
 

Bedendo, Hannan & Khamis on one year deals.
I take serious issue with Hannan being labelled a “silky left footer”. The blokes pure working class denim.
 
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