ATG squatten niet zo goed voor gezonde sporters

[Silk]

Ik proef soms de opvatting op dit forum dat ATG optimaal is om blessurevrij te trainen. Nu heb ik het volgende pdfje onder ogen gekregen waarin het tegendeel wordt bewezen. Ze beweren dat parallel squat het best is als het gaat om blessure vrij trainen. Het is nogal wetenschappelijke taal, maar er is vast iemand op dit forum die zijn mening wil geven over de betrouwbaarheid van dit artikel.

http://www.mlmixrun.com.br/artigos/K...he_dynamic.pdf

Conclusie:
For athletes with healthy knees, performing aparallel squat is recommended over the deep squat, because injury potential to the menisci and cruciate and collateral lig-aments may increase with the deep squat.

Onderzoekswijze:
An exhaustive search of MEDLINE (1966 to April 2000)
and SPORTDiscus (1949 to April 2000) research databases
was conducted to identify scientific literature relative to the
biomechanics of the dynamic squat. The search strategy
employed initially involved examining all fields containing
“squat” and all fields containing “squat” AND “biomechan-
ics.” Because the dynamic squat is the focus of this review,
all literature relative to the isometric squat was excluded
from the search. In addition, only studies published in peer-
reviewed scientific journals, or published as conference
proceedings/abstracts from scientific conferences, were
considered for inclusion in this review. From the research
database searches, it was determined that barbell squat, the
isotonic machine squat, and BW squat comprised the squat
biomechanics literature. Most studies that examined the
biomechanics of the dynamic squat have focused on knee
biomechanics. Therefore, this review was limited to scien-
tific studies that quantified knee biomechanics during the
barbell, machine, and BW dynamic squat exercises. Dy-
namic squat studies that quantified knee biomechanics have
primarily focused on three major areas: 1) knee forces
comprising tibiofemoral shear force, tibiofemoral compres-
sive force, and patellofemoral compressive force; 2) knee
muscle activity from the quadriceps, hamstrings, and gas-
trocnemius; and 3) anteroposterior and mediolateral knee
stability. An understanding of knee biomechanics during the
squat is important because a strong and stable knee is
paramount to an athlete’s success or a patient’s rehabilita-
tion. Therefore, the purpose of this review was to examine

knee forces, knee muscle activity, and knee stability during
the dynamic squat exercise.

[dynobet]

For athletes with healthy knees, performing aparallel squat is recommended over the deep squat, because injury potential to the menisci and cruciate and collateral lig-aments may increase with the deep squat.

Ik zie niet de data die deze conclusie onderbouwd en hard kan maken dat dit daadwerkelijk zo is. Vandaar wellicht ook dat er staat MAY.

Ikzelf ben van mening dat je zo diep moet gaan dat je stabiel staat, ten alle tijden een correcte houding van de rug hebt en gedurende de hele beweging de spanning moet kunnen houden op de oefening. Waar dit punt ligt qua diepte verschilt nogal van persoon tot persoon en heeft ook veel te maken met je ervaring/mobiliteit/flexibiliteit.

ATG is dus zeer zeker niet altijd beter. Zo diep gaan als jouw lichaam onder optimale omstandigheden om te squatten toelaat wel (mijn mening).

[inferno_0666]

Er staat niet in hoe zij tot die conclusie is gekomen. Enkel wat vage referenties naar studies, maar ook niet welke. In het forum zijn overigens meerder artikelen over dat onderwerp geplaatst die wel goed zijn onderbouwd. Men heeft het dan over lager dan parallel squatten en niet ATG; men haalt de 2 vaak door elkaar dus het is belangrijk om erop te blijven hameren dat dit niet het geval is.

[Patriciaaa]

Gewoon doen wat goed voelt. Als je ervan overtuigt bent dat het niet goed is, dan gaat het je zeker problemen opleveren.

Beiden zijn gewoon andere oefeningen met andere doelen. Beetje suf om de ene als slecht te bestempelen, ze hebben gewoon beiden voor en nadelen. Doe wat past

[inferno_0666]

Deze is al eens eerder geplaatst vorig jaar, is wat uitgebreider en er zijn verwijzingen naar de bronnen.

Ter info:
PCL - achterste kruisband in het kniegewricht
ACL - voorste kruisband in het kniegewricht

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3 Squatting Myths That Refuse To Die


February 9, 2012






The squat probably gets more of a bad rap than any other strength training movement, especially the barbell back squat. Many people choose the leg press machine instead, blaming the squat on their knee or low back injuries. Others will only perform partial squats, fearing injury if they go too deep. Avoiding injury is always good, but avoiding the squat is like refusing to walk because you’ve seen other people trip and fall on the sidewalk. Millions of professional and amateur athletes around the world somehow manage to squat regularly without hurting themselves.

The fact that a properly performed squat is inherently safe has been presented many, many times by others who are much more qualified than I am. In spite of this, the misconceptions persist, so I believe that the available evidence bears repeating. This article will deconstruct what may be the three most common squatting myths: Squatting below parallel is bad for your knees, your knees should never go past your toes and squatting is bad for your back. I will also present two very basic guidelines that should keep just about anyone injury-free when squatting.


Myth #1: Squatting below parallel is bad for your knees

Despite the ability of the knee joint to provide an average of 140 degrees of flexion, the idea has been promoted that knee flexion should be limited to 90 degrees during a squat. This myth can be traced back, at least in part, to a single study published in 1961 by Dr. Karl Klein at the University of Texas. Dr. Klein determined that a group of competitive weightlifters displayed greater laxity at the knee joint than a group of non-lifters, and issued a blanket recommendation against squatting below parallel. The study was of very low quality, though, and Dr. Klein was seeking to validate his bias against squatting below parallel. Somehow, this erroneous belief was adopted by the general population and has remained standard dogma ever since, even though it’s been disproven many times over.

Powerlifters squatting double their body weight, to depths of 130 degrees of knee flexion, have been shown in studies to have more stable knee joints than individuals who do not squat. In fact, separate studies have revealed that the knees of those who regularly squat deep are more stable than distance runners and basketball players! In one study of female volleyball players, researchers concluded that there was no statistically significant increase in peak forces at the knee when squatting to depths of 70, 90, and 110 degrees of knee flexion. Yet another study showed that forces on the ACL are reduced as the knee is flexed beyond 60 degrees, and forces on the PCL are reduced as the knee flexes past 120 degrees. Still further studies show that powerlifters who are squatting over twice their body weight experience shearing forces on the knee that approximate only 25% of the maximal tensile strength of the ACL, and 50% of the maximum strength of the PCL.



If you only do partial squats, then you can only receive partial benefits

Obviously, this doesn’t mean that just anyone should attempt to squat with a load equaling twice their body weight on their back. While those feats clearly demonstrate what the human knee is capable of, the important point is that forces on the knee are actually reduced as squatting depth progresses beyond parallel. How deep should you go, then? Well, once you are able to drop below parallel, meaning that the crease at the top of your hips is below the top of your knees, then you should only squat as deep as you can without losing form. If your lower back starts to round, that’s your stopping point. And if you can’t squat below parallel without rounding your lower back, then don’t increase the resistance until you can. It’s also worth mentioning that you should utilize a stance that allows you to squat between your legs and not on top of them, because pressing the hips directly against the calves under a heavy load can create a dislocating effect on the knee.

Squatting below parallel has the additional benefit of significantly increased activation of the gluteal muscles. The deeper you squat, the greater the glute activation. Whether you’re seeking to improve your performance or your appearance, you’re not doing yourself any favors by leaving the glutes out of the picture.


Myth #2: Your knees should never go past your toes

This one is about as mythical as you can get, as it’s hard to find much information at all regarding it’s origin. Search online and what you will find are numerous references to one study from 1978 at Duke University which found that keeping the lower leg as vertical as possible reduced shearing forces on the knee. I wasn’t able to find the actual paper and there’s no available explanation I’m aware of as to why those researchers believed the knee was incapable of sustaining those forces, or how they performed their study. Whether this is the actual origin of the myth or not, an obscure study with zero supporting evidence is hardly any basis for providing any legitimate rules about squatting.

There was one study conducted in 2003 that essentially recreated this scenario by having experienced weight lifters squat under two conditions. First they squatted normally, allowing their knees to travel forward past their toes. Then, they repeated the movement while restricting forward movement of the knees beyond the toes. This reduced torque at the knee by about 22%, and it also increased torque at the hips by over 1000%. (What appears to be a disproportionate redistribution of forces can be explained by a change in torso angle.) This shows that you can reduce torque at the knee by preventing them from going past the toes, but it doesn’t prove that this is necessary. Interestingly, it appears that letting the knees travel past the toes was part of the “normal” method of squatting for those experienced lifters, and the prevention of forward movement of the knees was accomplished by artificial means. In either case, the volunteers in the study seemed to be fully capable of handling the load without incident or injury.



Go ahead, tell him he’s doing it wrong and see what he says

This shouldn’t be surprising, because your knees go past your toes all the time when you run, jump, walk, sit down, and stand up. This is made possible in part by the natural dorsiflexion range of motion at the ankle. Furthermore, when your knee is flexed, some tension is removed from the gastrocnemius muscle at the knee joint. This allows the ankle to dorsiflex through a greater range of motion than when the knee is fully extended, and permits movement of the knee over and past the toes. Why, all of a sudden, will your knees get blown out if they go past your toes during a squat? It’s amazing how our bodies work but it’s a shame that some people remain so unaware of its capabilities.

The actual distance your knees will travel is dependent upon which type of squat you’re doing, as well as your body proportions. Are you doing front squats? Your knees are definitely going over your toes, no matter what. If they don’t, you’re doing them wrong. Do you have long femurs? Your knees will go further over your toes than an individual with shorter femurs, regardless of which type of squat you do. Are you doing split squats? In that case, your front knee may not go beyond the toes at all, but your back knee will travel well past the toes on that respective leg. Are you doing a back squat? As long as you push your hips back into the squat appropriately, and stay balanced on your midfoot throughout the movement, it doesn’t matter where your knees end up. Let them travel as far forward as they need to.


Myth #3: Squats are bad for your back

This is like saying food makes you fat. The idea that squats will hurt your back gets perpetuated by people who perform squats incorrectly, and sometimes by woefully misinformed professionals who claim to know what they are talking about. A recent article posted on Journal Sentinal Online titled, in part, “Squat lifts likely cause of stress fractures in young athletes” claims that performing squats with good form puts the spine at risk of injury, based on a new study. The main problem with the study they reference is that the researchers don’t know how to properly perform a squat. The pars fracture cited as the predominant injury risk is typically an overuse injury involving hyperextension of the spine, and the increase in “sacral slope” they measured is another indication of hyperextension.

By contrast, the goal in any squat should be to maintain a neutral spine. If there is hyperextension of the spine, then the squat is not being performed correctly. Furthermore, as the weight gets heavy in a squat, the challenge is to resist excessive spinal flexion, not extension. It’s much more common to observe a lifter who is rounding their back when squatting, even when lighter loads are being used. This error can easily be corrected by learning proper form and using a manageable resistance. That study and related article fail on such a massive scale, yet the faulty arguments still have the potential to exert undue influence on the general public for many years to come.

Other concerns focus on spinal compression in the squat, and again with the back squat usually being singled out. Some individuals will assert that placing a load on the back is an unnatural movement that should be avoided. The truth is, the human spine is very capable of handling compressive forces. The trick is to load the spine without creating excessive shear, which can be accomplished by keeping the torso as upright as possible (and practical, considering which squatting variation is being used), as well as by keeping the spine in neutral. The ability to maintain an erect torso with a neutral spine will be the limiting factor in the squat for most people. This need not be interpreted as a reason to avoid the squat, though. It simply requires that more attention be given to proper form instead of the amount of weight being lifted. If squats hurt your back and you haven’t had a recent injury or chronic pain issue, then you need to fix your squat. My suggestion is to seek advice from someone who knows how to squat!


Safe squatting and mythbusting basics

Can I promise that no one will ever get hurt doing squats? Well, no, there are no absolute guarantees, and freak accidents do happen. Even the idea that you won’t get hurt if you’re bigger and stronger sounds nice in theory, but in reality it’s impossible to predict and/or protect against all injuries. You can be sure, however, that when you squat correctly, your chance of injury will be very, very slim. Properly supervised weight training has been shown to have an extremely low risk of injury, lower than soccer, rugby, basketball, football, gymnastics, tennis, and even badminton. This may seem surprising or even hard to believe, especially if you’ve gotten hurt while lifting weights, but it makes sense if you understand that weight training can and should be performed in a much more controlled environment, absent the chaos and unpredictability inherent to many sports. Weight lifting injuries can be avoided 99.99% of the time.

There are two basic tips that will help you squat safely and I’ve already referred to them in this article. The first is to squat with proper form, simple as that. Admittedly, the squat can be a tricky movement to master, especially the back squat. How do you know if your form is good? The video in my previous post about Hip Drive should give you a good idea of how a squat should look, comparing three different squat variations. If anything hurts when you squat or the movement feels awkward or imbalanced, those are good indications that you’re doing something wrong or using too much weight. And very importantly, if your lower back is rounding at the bottom of your squat, that is an issue that needs to be addressed before you start adding more weight. I explain how to do this in my post about maintaining a neutral spine in the squat. Take whatever time is necessary to learn proper form.



Whichever squat variation you use, start light and make gradual progress

The second tip is to squat within your limits, adding resistance conservatively. This will allow your body to recover and adapt, a concept that is completely ignored when you read or hear about the supposed dangers of squatting. Amazingly, your body will adapt to the demands placed upon it, as long as you don’t exceed its current ability or its capacity for recovery. Usually, this is more of an issue with men, for whom its tempting to add 50, 75, or 100 lbs. at a time to the bar in an attempt to force progress or prove their masculinity. (Women typically go in the opposite direction, hesitating to add much weight at all out of an irrational fear of getting big and bulky and losing their femininity, another stubborn myth that has no basis in reality.) A good way to avoid this mentality is to approach each squatting session as an opportunity to practice the squat, rather than a chance to show off how much weight you can lift. That’s a bonus tip: keep your ego in check.

Squats are a skill like any other movement, and many of us have been out of practice for a long time. It can be difficult to learn (or re-learn) how to squat and labeling them as dangerous provides a convenient excuse for omitting them from a workout program. You don’t have to be that person who always looks for the easy way out! As long as you’re willing to make the effort required to learn how to squat correctly and patiently allow your body to adapt, you’ll be rewarded by making consistent progress with minimal injury risk. On a personal note, I’ve had numerous people over the years warn me that I was going to destroy my knees from deep squatting. Well, I’ve been squatting well below parallel for the last ten years and I’ve never had an injury. I’ve also never had a client who I couldn’t train to perform some variation of a deep squat, even those with previous back or knee injuries, or both. They squat with skill and confidence, undeterred by unsubstantiated myths, and you can too.


Sources
1. Schoenfeld, BJ. Squatting kinematics and kinetics and their application to exercise performance. J. Strength Cond. Res. 24(12): 3497-3506. 2010.
2. Fry, A.C., J.C. Smith, and B.K. Schilling. Effect of hip position on hip and knee torques during the barbell squat. J. Strength Cond. Res. 17(4): 629-633. 2003.
3. Caterisano, A., Moss, R.F., Pellinger, T.K., Woodruff, K., Lewis, V.C., Booth, W., and Khadra, T. The Effect of Back Squat Depth on the EMG Activity of 4 Superficial Hip and Thigh Muscles. J. Strength Cond. Res. 16(3): 428–432. 2002.
4. H. Orloff, G. Veil, R. Askins. (1997). Forces on the lumbar spine during the parallel squat. Conference Proceedings Archive, 15 International Symposium on Biomechanics in Sports. http://w4.ub.uni-konstanz.de/cpa/article/view/3648.
5. Shea, J. Deep Squats. http://www.apec-s.com/wp-content/upl...eep-Squats.pdf
6. Fauber, J. (Nov. 2, 2011). Squat lifts likely cause of stress fractures in young athletes, study finds. Squat lifts likely cause of stress fractures in young athletes, study finds - JSOnline
7. Rippetoe, M. & Kilgore, L. (2007). Starting Strength Basic Barbell Training 2nd Edition. The Aasgaard Company.
8. Calais-Germain, B. (1993). Anatomy of Movement. Eastland Press.

[Silk]

Bedankt voor de reacties.

[adon1s]

Ik ben wel van mening dat een 'full' squat waarbij niet gelet wordt op het onder spanning houden van het lichaam niet bijdraagt aan een gezond lichaam. Hierbij spreek ik puur uit mezelf. Ik zie regelmatig een 'full' squat met 'butt-wink'. Er is nog een idioot ala Rippetoe die ook nog mensen motiveert om dit te doen. Mijn advies is om de dave tate squat te leren en niet de Rippetoe squat. Een butt-wink is niks anders dan spanning verlies. Ik zeg wel dat je flink diep moet squatten, ook dieper dan pararel, maar zo ver als mogelijk is in vele gevallen te diep om spanning te behouden..

[nbtp]

Rippetoe promoot dan ook geen butt-wink maar een hip drive, wat als je het boek gelezen hebt zeker niet hetzelfde is..
Niet dat ik zeg dat dave tate zijn manier van squaten minder goed is, ieder zijn ding maar het ene is zeker niet blessure gevoeliger dan het andere mits beiden correct uitgevoerd worden.

[Leroy K]

interressant stuk ! Maar waarom word er niks aan genetisch aanleg verwijt? Niet iedereen kan evenveel hebben..

[akito]

Ik ben wel van mening dat een 'full' squat waarbij niet gelet wordt op het onder spanning houden van het lichaam niet bijdraagt aan een gezond lichaam. Hierbij spreek ik puur uit mezelf. Ik zie regelmatig een 'full' squat met 'butt-wink'. Er is nog een idioot ala Rippetoe die ook nog mensen motiveert om dit te doen. Mijn advies is om de dave tate squat te leren en niet de Rippetoe squat. Een butt-wink is niks anders dan spanning verlies. Ik zeg wel dat je flink diep moet squatten, ook dieper dan pararel, maar zo ver als mogelijk is in vele gevallen te diep om spanning te behouden..

Lees eerst het boek eens 'idioot' (om je in je eigen taal aan te spreken). jeez van iemand als jou had ik toch wel iets meer intelligentie verwacht.