written by, Mood
It appears that the Niners players in the ShanaLynch regime are having an unusually high incidence of soft tissue injuries.
The mechanism is clear -- Newton's laws and limits to tensile strength and flexural rigidity of tendons and ligaments. It's known that repetitive use, combined with overuse and microtrauma, may cause a progressive attrition of tendons. Wilson's meniscus did not rupture from standing up in the training room. His transferring his weight to his legs that involved a damaged meniscus was likely the final straw that broke the camel's back, so to speak.
If the answer was simple as better stretching, training and equipment, sports science would have had a clear answer by now. On the contrary, every major study has shown that stretching does not reduce injuries:
newcastlesportsmedicine.com.
Strength training, etc., can strengthen tendons and ligaments to a limited degree but 200+lb men moving at 4.4 speed creates huge stresses. No health and training staff can help prevent such injuries because they cannot change the laws of physics. As the sports doctor David Chao has stated, it's easy to blame medical but many factors in injury from player selection, pre-existing injury, style of play, scheme, fatigue, playing conditions and of course bad luck are in play.
twitter.com/ProFootballDoc/
I've an unproven hypothesis in this regard. The root cause of this problem may be the kind of players ShanaLynch has recruited. They have placed a premium on creating a team of large, powerful players who play very fast. Such players, whether in contact or non-contact situations, place excessive stresses on their ligaments and tendons when they change directions sharply because of the massive accelerations involved for such large masses, which in turn imposes very large forces (and thus, large stresses) on the tendons and ligaments. Either players have to be large and slow, or small and fast, to reduce these stresses that may otherwise cause the tears.
However, I should clarify that I am not referring to the straight-line speed of large humans like Seattle's Metcalfe. I'm also strictly discussing soft tissue injuries, not bone injuries and concussions.
Instead I am referring to large humans changing directions sharply at medium to high speeds that put large torques on all musculoskeletal parts of the body, including the tendons and ligaments.
These sharp lateral movements causing high accelerations and high rotational stresses are more frequent in zone running schemes and in the Niners’ defensive philosophy of "all gas no brakes".
Consider the Wide 9 rush vs. the bull rush. In the wide 9, the rusher (Bosa, Ford) is running in a curve to avoid the tackle on the way to the QB -- constantly changing direction while traveling at high speeds (to cover greater distance to QB). Thus the rusher in wide 9 rush is acceleration at all points during the rush over longer distances putting extra rotational load on their tendons and ligaments compared to DEs coming off stunts where movements are in smaller spaces and the changes of direction are happening at lower speeds.
Also consider how the safety play has changed from the Lott - Lynch approach through visualizing running violently through the players, to the Tartt - Moore sideline-to-sideline mobility and running around defenders. These motions involve high rotational acceleration motions that may slowly wear down and degrade tendons and ligaments unless there is enough opportunity for rejuvenation.
It would be an interesting idea to look for correlations. For example, calculate a relevant metric for each player, e.g., ratio of weight to the product of 20 yard short-shuttle time and three-cone times.
Risk = weight / (short-shuttle time X three-cone time)
A larger number means higher risk of injury. Now take the average over the entire 53 and plot against such injuries per season.
These are just idle speculations. However, I expect that we will learn more about these injuries and their causes over the next several years leveraging machine learning techniques on MRI images that may be able to spot changing morphology of these soft tissues and detect damage to the tissues resulting from regular play so that there may be interventions possible before such catastrophic events as tears.
Mood - nice piece of work. I also 'was' in the same thought process of the type of players that Shanny is enamored with as being 'injury prone'. It would be interesting to compare the Niners injuries prior to the Shanny regime.
ReplyDeleteThanks, Under. It's kind of difficult to compare injuries across the board from regime to regime when other factors are also changing, as David Chao points out. My observations are strictly on soft tissue injuries. My point is that it is not that the players are prone to soft tissue injuries, but that the playing style relative to their size itself causes excessive attrition to their tendons and ligaments which eventually leads to tears.
DeleteKyle Shanahan explains why 49ers didn't trade for Julio Jones
ReplyDeletehttps://sports.yahoo.com/kyle-shanahan-explains-why-49ers-001954589.html
This comment has been removed by the author.
ReplyDeleteGood article, Mood, but I disagree on some points. With regards to stretching, most of the pre-game stretching I see seems to be quite ballistic and looks like a competition as to who can stretch the futherest. Stretching should be the exact opposite of that - allowing the muscles to relax and not tighten because they are being stretched beyond the comfortable limits of the individual. In my opinion a lot of these guys are always tight and this contributes greatly to the non-contact injuries ("Shanahan explained that Jeff Wilson Jr. was hurt after getting out of a chair awkwardly. He said Tarvarius Moore was doing a drill on air with nobody around him and his Achilles went out."). I still think the non-contact injuries can be reduced with a proper program that emphasizes to the players the need to take care of their bodies better - a program which is uppermost in the player's mind and not just pushed by the trainers/therapists. In other words, players are always thinking about it and not merely waiting or responding to queus from trainers/coaches/therapists. In other words again, cultivating more body awareness. Young people don't normally think this way, in general, and why should they. But, imo, football players have to.
ReplyDeleteNo doubt you are right about large men changing direction rapidly and running faster than anyone ever imagined even a decade ago. Your hypothesis regarding the types of players ShanaLynch recruit is interesting and appears to have merit.
All in all a good article that was an enjoyable read.
Thanks, Cubus.
DeleteIt's very likely that the movements that "caused" Wilson's and Moore's (and Skule's) injuries made the final incremental contribution to the tears that were already damaged from attrition. The focus will probably have to be on the routine, repetitive motions that are causing these tendon and ligament attrition. Note that we are not talking here about muscles which regrow rapidly from these microtears and builds added muscles.
Pretty much every major study has shown that stretching has no effect on preventing injuries despite what we may want to believe. At some point, we fans may have to accept that these billion-$$ franchises are spending enough money to use the best expertise in the field in trying to keep the players healthy :)
Mood
ReplyDeleteYou raise some interesting question with respect for soft tissue injuries.
* You're correct, that stretching does not prevent injuries, study after study has confirmed this.
* You're also correct that The root cause of the (soft tissue injury) problem is the kind of players ShanaLynch has recruited. But this is NOT unique to ShanaLych. NFL teams have been drafting players that are bigger and faster than previous players. (with the exception of LB's). In the 60's O-linemen were 250-275 pounds, compared to 300 plus pounds today. MLB's (Butkus) weighted ~245, run a 4.8s, 40 slower than todays linebacker, that weighs (on average 220 pounds) and run a ~4.6s 40.
* The one factor you fail to mention is fatigue.
* Your article reminded me of a recent article that I had read and may interest you. While there's no direct correlation to NFL players, it does address soft tissue injuries.
WHY SOME ATHLETES ARE INJURY-PRONE....
https://www.newscientist.com/article/dn6211-why-some-athletes-are-injury-prone/
Geep,
ReplyDeleteI should reiterate that I'm not focusing on just bigger and faster players. I'm focusing on big players routinely making frequent changes in direction when moving at relatively high speeds. The key words here are "changes in direction" (increased angular acceleration and hence increased torque and thus more shear stress) and "routinely" (mechanical fatigue-induced microtears from stress cycling as pointed out in the 2004 paper you linked to).
I agree that fatigue is a factor. There are two kinds of fatigue. There's biological fatigue that results in athletes losing balance or taking a wrong step or something similar that compromises their body's ability to resist injuries. Then there is mechanical fatigue from stress cycling. The Niners in OTA are fresh and not really suffering from biological faigue
Mood
ReplyDeleteI understand and agree that your point was "big players routinely making frequent changes in direction when moving at relatively high speeds." And The key words here are "changes in direction" (increased angular acceleration and hence increased torque and thus more shear stress)
While I'm not disagreeing with you, there are other factors such as this article points out.
* Why so many NFL injuries this season? One sports-medicine doctor thinks he knows why....
https://www.yahoo.com/now/why-so-many-nfl-injuries-this-season-one-sportsmedicine-doctor-thinks-he-knows-why-141643231.html
Interesting article, thanks. Yes, there are many factors going into injury consideration, but teams are working hard to limit or eliminate many of them. Hopefully, that will bears fruit.
DeleteNice article Mood.
ReplyDeleteQuestion for you though, are the 49ers the only team drafting and signing these types of players? I don't believe that is the case. Yet the 49ers are consistently at the top of the league for injuries. For mine there has to be something else beyond just the size and athleticism of the player.
I would also argue that zone running schemes don't necessarily place a lot of stress on the body, at least not more so than other schemes. The OL tend to not have to carry as much weight, and they don't need to be changing direction much. The RBs are tasked with, essentially, making one cut, while other schemes will often require the RB to make more movements to find the gap. So again... I think there is more to it.
Some of it probably is just a bit of bad luck, but over time that excuse wears thin.
I suspect some of it just comes down to bringing in players with injury histories, who are more naturally susceptible to injury. But then guys like Moore and Skule don't have histories of injury.
Some of it I think may have more to do with how these players are being conditioned by the 49ers strength and conditioning staff - I'm no doctor or physio, but it may be they are adding too much muscle to certain parts of their body without sufficient counteracting muscle and not enough work on flexibility to maintain suppleness of joints and limbs. It may also just be they are not being taught proper techniques in weight training to minimise stress on the body.
I also expect some of it comes down to players training on their own a lot during the past 18 months, potentially learning some bad habits and not effectively working all of their body ready for the rigours of football, then being thrust into team activities that may potentially have been a little more physical than needed/ they were ready for.
One thing that seems to be the case is the 49ers players put a lot of work in during the offseason. Perversely, this may be contributing to the issues.
You nailed it Scooter! Spot on ... as usual!
DeleteAnd let me add the one thing I believe may possibly be to blame most besides the things you mentioned ... Recovery. I have a hunch that these players are doing too much weight training, and putting more stress on their bodies than they are allowing for in terms of proper recovery! I believe a proper level of recovery, and by that I mean proper rest, combined with nurishment, that is most effective at preventing a lot of these injuries. Let's face it, some of it is the nature of the sport, but there simply has to be another factor involved with this team, because the law averages haven't added up over the last decade, and especially during the current regime.
Scooter,
DeleteThanks.
> Question for you though, are the 49ers the only team
> drafting and signing these types of players? I don't
> believe that is the case.
No, it's not the players they draft. It's what they ask the players to do consistently. Are they the only team asking the players to make football moves that puts excessive torques on a regular basis. Dunno, -- I don't follow Rams and Packers that closely.
I'd think that RBs who run power scheme do not have the same acceleration that zone scheme demands. But I don't have GPS data to back me up, though. It seems to me that the acceleration resulting from the single sharp cut that the back makes in zone runs to hit the gap after starting with a quick burst is significantly higher than the power running RB following blockers and changing directions at lower speeds.
It's quite possible I am completely off base. But I don't think the reason for such high incidence of soft tissue injuries is something simple and obvious.
On a related note, I heard an inane (insane?) question at Kyle's latest presser: "What changes in practice methods have you made since you became a HC in order to reduce injuries?" It sounded like something Grant would ask. It assumes that (a) the Niners know what changes would be needed to be made to reduce injuries, (b) they have been running control experiments to make sure their hunch was right and were losing millions of $$ in lost player time in the process, and (c) the changes they have made to reduce injuries obviously hasn't worked -- then why ask?
Have a good weekend, all. I'm taking a few days from work off to take our teenage kids camping and fishing in the Eastern Sierras to start off their summer vacation.
Have a great break, Mood!
DeleteMood, nice drop.
ReplyDeleteThe injuries in the modern day of football is very baffling for me.
I’ve been watching football since the early 60’ and can’t recall if the numbers of football injuries during that era match the current numbers.
I really can’t remember (sure age has something to do with it) any major or top players getting hurt as often as today.
The play back in the day was much more fierce and brutal than today’s game. I remember raiders vs steelers games that teetered on criminal intent in tackling.
I don’t recall players like Jack Tatum and Ronnie Lott ever suffering major injuries even when using their bodies like human missiles.
Today’s game has been watered down with all the new rules protecting the players. I don’t adhere to the notion that Shanahan should shoulder some blame for the type of players he’s drafted. I’m not sure that I could lock in on one reason as I believe that there are many that have caused the flurry of injuries over the last few years.
And I have to believe that the 49ers will be taking a serious look into this issue before training camp starts.
49ers sign OL Senio Kelemete to 1-year deal.....
ReplyDeleteThe San Francisco 49ers have signed offensive lineman Senio Kelemete to a one-year deal and waived offensive lineman Justin Skule with an injury designation Friday to make room on the roster.
Kelemete was originally drafted by Arizona in the fifth round in 2012 and has played 88 games in nine seasons with the Cardinals, New Orleans and Houston.
Kelemete played 14 games with five starts for Houston last season.
Tarvarius Moore tears Achilles for 49ers....
ReplyDeletehttps://sports.yahoo.com/justin-skule-tears-acl-tarvarius-155645660.html
GUESS WHO GOT THE LAST LAUGH.....
ReplyDeleteWhy Kyle Shanahan laughed at NFL draft QB preference perception.
https://sports.yahoo.com/why-kyle-shanahan-laughed-nfl-220952310.html