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Author Topic: Query About Knee Health  (Read 11406 times)

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Offline Query

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Query About Knee Health
« on: September 16, 2010, 01:55:23 PM »
I once saw some kids going from shoot the ducks to lunges (by rotating the leg outwards, bending the knee, and sliding or lifting it back), so I started practicing going back and forth between the two.

Can anyone explain to me why deep knee bends are bad for the knees?

And is that true for everyone, or does it have something to do with your injury history or internal anatomy?

Some health advice is directed towards group fitness instructors, who don't have time or training to investigate the individual differences among their customers, but try to avoid harming anyone who might happen to walk into their class. I was once told the standard aerobics class advice against bending the knee past 90 degrees in lunges was an example of that. (Skating lunges, and many of those used in various types of performance dance, go beyond 90 degrees.)

E.G., is it only bad for people who have damaged their knee cartilage or cruciate ligaments, or something like that?

There are standard Yoga poses where you more or less go into a fetal position (e.g., "Child Pose"), with fully bent knees. Are those supposed to be bad for you too? If bad, is it bad for everyone?


Offline sk8Joyful

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Re: Query About Knee Health
« Reply #1 on: September 16, 2010, 05:36:56 PM »
I once saw some kids going from shoot the ducks to lunges (by rotating the leg outwards, bending the knee, and sliding or lifting it back),
so I started practicing going back and forth between the two.
As a beginner, I have done this to some extent -
because when I get down to just about the boot, I lose the balance & end up sitting giggling no less.
I rotate the leg outwards, and do some sorta Lunge instead. Somehow I can manage this better from down there,
but not from a standing position, where I am not rotating the leg sideways enough.  Why is that?

Can anyone explain to me why deep knee bends are bad for the knees?
I thought the deeper the knees, the better!  ;D Then again, what do I know.

There are standard Yoga poses where you more or less go into a fetal position (e.g., "Child Pose"), with fully bent knees.
Side-lying, I sleep in this position every night, at least several hours. - I wonder now if it's possible to sleep with foot behind head,
similar to unborns, which position I had until 2 yrs. ago.

I wonder too if there are Flexability-clinics for Contortionist positions, which will get people a Biellmann  ;D faster.  



Offline jjane45

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Re: Query About Knee Health
« Reply #2 on: September 16, 2010, 10:50:06 PM »
I am seriously concerned about sit spin and knee damage now...

Offline Query

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Re: Query About Knee Health
« Reply #3 on: September 17, 2010, 01:05:42 AM »
I originally posted my query in a thread where someone had claimed low shoot the ducks (and, by implication, sit spins) were bad for one's knees, because they were too deep a knee bend.

I was merely trying to figure out whether the claim was considered to be universally correct, or whether it just applied to people with certain types of knee (or back?) injury.

I do have a knee problem: My knee caps move a bit side to side, creating pain and potentially wearing cartilage, as I rise up from one leg knee bends and raises (e.g., shoot the ducks). This occurs (says a PT) because I am trying to do it all with my quad (the big leg muscles are in front of the knee), instead of properly involving the many other muscles which stabilize the kneecap position (e.g., psoas, obliques, abdominals, lower back muscles, gluteous family muscles, in fact the entire hip flexor family, etc.), by pulling at a variety of angles from all sides, as he says most people do. (In addition, insufficient use of those muscles leaves them cold, so they can't stretch, which severely limits forward bend, back bend, wide leg stance flexibility.) Knee bends and raises, lunges, and sitting in full squats, as well as leg raises in many different directions, are part of the exercise regimen the PT advocated to fix it, so I guess he doesn't believe bending the knee is bad - for me.

He blames a lot of health problems on all the time many of us sit in western style chairs, which only place tension on the quads, and leave us long-term in one body position: he thinks squatting positions, which of course involve very low knee bends, help keep people in other cultures healthy, because more muscles are involved, and that we should also use a wider variety of chair styles to exercise and stretch more parts of the body.


Offline fsk8r

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Re: Query About Knee Health
« Reply #4 on: September 17, 2010, 02:53:58 AM »
I originally posted my query in a thread where someone had claimed low shoot the ducks (and, by implication, sit spins) were bad for one's knees, because they were too deep a knee bend.

I was merely trying to figure out whether the claim was considered to be universally correct, or whether it just applied to people with certain types of knee (or back?) injury.

I do have a knee problem: My knee caps move a bit side to side, creating pain and potentially wearing cartilage, as I rise up from one leg knee bends and raises (e.g., shoot the ducks). This occurs (says a PT) because I am trying to do it all with my quad (the big leg muscles are in front of the knee), instead of properly involving the many other muscles which stabilize the kneecap position (e.g., psoas, obliques, abdominals, lower back muscles, gluteous family muscles, in fact the entire hip flexor family, etc.), by pulling at a variety of angles from all sides, as he says most people do. (In addition, insufficient use of those muscles leaves them cold, so they can't stretch, which severely limits forward bend, back bend, wide leg stance flexibility.) Knee bends and raises, lunges, and sitting in full squats, as well as leg raises in many different directions, are part of the exercise regimen the PT advocated to fix it, so I guess he doesn't believe bending the knee is bad - for me.

He blames a lot of health problems on all the time many of us sit in western style chairs, which only place tension on the quads, and leave us long-term in one body position: he thinks squatting positions, which of course involve very low knee bends, help keep people in other cultures healthy, because more muscles are involved, and that we should also use a wider variety of chair styles to exercise and stretch more parts of the body.



i'm not a medical expert, but I would tend to agree that it's all the sitting down which creates these problems. If the knee wasn't meant to bend, why is there a joint there which bends? The knee isn't designed to rotate, so all the cautions about not twisting the knee are there because the knee isn't designed to twist, but there shouldn't be cautions about actually bending the knee. And for correct lifting of heavy objects they actively encourage bending knees.

With most of the injuries I've heard people commonly get with knees they sound like there's a good deal of rotational force involved. If your muscles are out of balance around the knee that is possibly self-induced rotational force (which sounds like what you may have Query but that the PT is trying to correct), but that doesn't mean that you should stop bending your knees. Walking becomes incredibly difficult without bending them and stairs are virtually impossible.

Offline Sierra

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Re: Query About Knee Health
« Reply #5 on: September 17, 2010, 10:22:55 AM »
I'm pretty sure you just have to make sure knees are over toes when doing squats, sit spins etc. Not sure exactly why knees over heels would be harmful to the knees, though.

Offline fsk8r

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Re: Query About Knee Health
« Reply #6 on: September 17, 2010, 10:44:22 AM »
I'm pretty sure you just have to make sure knees are over toes when doing squats, sit spins etc. Not sure exactly why knees over heels would be harmful to the knees, though.

That's an easy way of saying that your knees should be aligned with your feet. If you twist your knees you can have your feet pointing forwards and your knees pointing sideways, which is a sure fire way of doing some damage.
As a phrase it's an easy check for people to make when they're in a large fitness class and the teacher can't pay individual attention to what you're doing.

When you're standing straight up your knees are over your heels (they're still pointing the same way as your toes). When you bend, the ankle tends to bend with the knees but they should remain aligned with your toes.

It still doesn't explain whether depth of squat is bad or whether its just poor form which is bad.

Offline jjane45

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Re: Query About Knee Health
« Reply #7 on: September 17, 2010, 11:19:03 AM »
I am trying to visualize when are knees over the heels in a squat position, assuming kneecaps face forward. Will it balance at all?

Offline Sierra

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Re: Query About Knee Health
« Reply #8 on: September 17, 2010, 12:10:12 PM »
I am trying to visualize when are knees over the heels in a squat position, assuming kneecaps face forward. Will it balance at all?
Not really, you just rock off the back of your heels onto your butt. ;D
That's an easy way of saying that your knees should be aligned with your feet. If you twist your knees you can have your feet pointing forwards and your knees pointing sideways, which is a sure fire way of doing some damage.
As a phrase it's an easy check for people to make when they're in a large fitness class and the teacher can't pay individual attention to what you're doing.

When you're standing straight up your knees are over your heels (they're still pointing the same way as your toes). When you bend, the ankle tends to bend with the knees but they should remain aligned with your toes.

It still doesn't explain whether depth of squat is bad or whether its just poor form which is bad.
Ah. So the mystery remains.

Offline Query

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Re: Query About Knee Health
« Reply #9 on: September 17, 2010, 12:21:22 PM »
I'm not medically trained, and have not consulted with the designer &). But saying that the knee isn't designed to rotate at all wouldn't make sense from a basic physics perspective. Knees, especially bent knees, rotate easily and naturally to a limited extant, without creating severe forces in bad directions.

Joints (like hinge joints) in steel or aluminum can be a tight fit, and can limit motion to specific axis, because those metals are fairly strong in all directions, quite unlike the materials out of which we are built. Designing joints a little loose and able to move and give a bit in any direction is a reasonable way to create a mechanical system using materials which are not strong in some directions. God or evolution or whatever you believe in did that right.

Taking anything to extremes is bad, whether it is excessive rotation, or excessive stabilization.

If you use excessive muscle stabilization to make your knees completely rigid against rotation, that leaves your knees with no give to take up undesirable direction forces, and doesn't spread those forces out over a sufficiently long distance, and so makes the knees more vulnerable. It makes more sense to leave them a little loose.

Anyway, as best I understand it, rotation of the knee is a somewhat different issue from bending it - or from my patellar (kneecap) tracking problem. Normal rotation doesn't normally create that problem, though extreme rotation could.

Many joints are stabilized within safe motion limits by continuous low level muscle tension of a network of adjacent muscles, which pull in many different directions. In my case, isolated single direction tension from just the quad group, with no sideways or oblique muscle tension components, doesn't provide the balance of forces needed to keep the kneecap within safe sideways motion limits. It's not so much an muscle imbalance, as it is a lack of forces along one dimension.

But my question about safe knee bend depth remains unanswered.

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Re: Query About Knee Health
« Reply #10 on: September 17, 2010, 02:10:01 PM »
To quantify the qustion before throwing it at PT... I guess the gradual bending takes maybe 1-2 seconds and then the position is held for 0.5-2 minutes, whether with or without angular momentum? Rotation of knee joint in either case is minimal IMO.

Offline Skate@Delaware

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Re: Query About Knee Health
« Reply #11 on: September 18, 2010, 07:30:31 PM »
I've heard both sides of the argument, but I've been doing deep squats forever. 

Query, have you tried taping your kneecaps or wrapping them (i.e. athletic-taping) so they don't slide around? My daughter has to do that with one of hers before she works out/runs because it's shot and will slide up her leg  :o
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Offline Query

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Re: Query About Knee Health
« Reply #12 on: September 18, 2010, 08:17:32 PM »
have you tried taping your kneecaps or wrapping them

No. Maybe I should try to look it up.


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Re: Query About Knee Health
« Reply #13 on: September 19, 2010, 08:57:14 AM »
No. Maybe I should try to look it up.


You might want to search under "McConnell Taping" I believe that might help you.
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Re: Query About Knee Health
« Reply #14 on: September 19, 2010, 10:01:05 AM »
I think what it all boils down to, our knees actually do wear from everything we do. In archeological digs, scientists can tell from a skeleton whether its previous owner was busy walking uphill-downhill all day carrying heavy stuff, or spent a lot of times down on hands and knees grinding wheat and cleaning floors, or was sitting with the back against a wall with the butt almost down on the floor and the knees really bent with the feet underneath the butt casually chatting to people and not working all day. Yes that deep kneebent (at least according to Discovery channel), day-in day out, they can tell from a skeleton so clearly it does wear, but so does every other kind of repeated activity.

I think it goes quite far to say that doing a certain exercise in skating will "ruin" your knees though. I mean sure, crawling around on hands and knees will ruin your knees pretty fast, that's why people who have to do that for work such as gardeners, certain types of industrial workers etc will wear protection for their knees. My student job involved work like that as well, we all were using something for the knees. I've never encountered something as disastrous as that for my knees in skating, although shoot-the-ducks somehow are by far the worst I've seen. I think it's something about having to balance left-right while you're also on a very deep knee bend. With hydroblades and sit spins the balancing isn't there so much because the edge already keeps the foot still in a way - I hope you guys know what I mean.
As long as you do things correctly and have a good muscle tone so there's enough space in the knee (because of the muscle inbetween the knee cap and knee for instance) it should be fine for most people, at least those without pre-existing problems such as arthritis, arthrosis, rheumatical inflammations, injuries, etc. A lot of people get ostoarthritis with age anyway, it's part of our body's aging process unfortunately and we've yet to figure out how to fix that.
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Re: Query About Knee Health
« Reply #15 on: September 21, 2010, 10:05:27 PM »
shoot-the-ducks somehow are by far the worst I've seen.
I think it's something about having to balance left-right, while you're also on a very deep knee bend.
whenever I try to skate (shoot-the-duck = what a sad name), I have to do it really fast,
else I either fall over down there, or I don't have the thigh-strength to get me back up, at this point.

How could that move hurt the knees, tho?

arthritis, arthrosis, rheumatical inflammations, injuries, etc. -
A lot of people get ostoarthritis with age anyway, it's part of our body's aging process unfortunately, and we've yet to figure out how to fix that.
Fortunately, increasing medical docs, help people (assumed/accepted "normal" aging-processes) either at least Stop :) ; or even reverse.


Offline JimStanmore

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Re: Query About Knee Health
« Reply #16 on: September 26, 2010, 05:46:55 PM »
I have been researching this same thing for a few months.  I was not only concerned about pain, but also not being to squat all the way down.  5 years ago I was slated for knee surgery, but the Air Force physician wanted to try one more thing because joint surgery is always an iffy proposition.  They would heat my knee with a wrap, have me do several strengthening exercises and then cool it down with a special ice pack.

Lo, and behold, the pain went away.  It turned out there was a muscle imbalance.  Doing deep knee bends with the imbalance caused the strong muscles to work too hard and inflamed the joint (ligaments/tendons), causing pain (and damage?) to the knee joint.   Of course, it happened again when I started skating last year because I did not keep up the muscle tone.  So, I know how to solve that with strengthening and balancing exercises.

The full squat stumped me until I came across a couple of orthopedists and chiropractors on the net who were/are competitive skaters.  The say that when you squat the backs of your thighs and calves touch.  This creates a lever action that tries to separate the knee joint.  That explains why my knee really starts to hurt when I try to sit on my heels.  That also seems to mean that the bigger the muscles the less you can squat down.  

It also means that going down TOO far (past initial stretching pain point) repeatedly is levering your knee joint opne in the same way that we do stretches to develop turn out and spread eagles - not good for the knee joint at all.

Offline JimStanmore

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Re: Query About Knee Health
« Reply #17 on: September 26, 2010, 06:07:46 PM »
In the On Ice Archive:

Could weak muscles cause front of kneecap pain? , fsf, Query, 4/2009

http://skatingforums.com/index.php?topic=449.new#new

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Re: Query About Knee Health
« Reply #18 on: September 26, 2010, 08:06:14 PM »
The full squat stumped me until I came across a couple of orthopedists and chiropractors on the net who were/are competitive skaters.  The say that when you squat the backs of your thighs and calves touch.  This creates a lever action that tries to separate the knee joint.  That explains why my knee really starts to hurt when I try to sit on my heels.  That also seems to mean that the bigger the muscles the less you can squat down.  

It also means that going down TOO far (past initial stretching pain point) repeatedly is levering your knee joint opne in the same way that we do stretches to develop turn out and spread eagles - not good for the knee joint at all.

But the thigh and calf have to touch for a good sit spin. Even if the sit is 90º without the thigh/calf touching, it's not a very pretty spin. And doing limited sit spins is not an option because I have to do a spin many many many times at each practice to get it to ever improve. Does strengthening the muscles around the knee help prevent the knee levering, or is it something to avoid no matter what? I work on hamstring strength alot to prevent quad/ham imbalance- what other muscles connect to the knee?

Offline fsk8r

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Re: Query About Knee Health
« Reply #19 on: September 27, 2010, 11:43:14 AM »
But the thigh and calf have to touch for a good sit spin. Even if the sit is 90º without the thigh/calf touching, it's not a very pretty spin. And doing limited sit spins is not an option because I have to do a spin many many many times at each practice to get it to ever improve. Does strengthening the muscles around the knee help prevent the knee levering, or is it something to avoid no matter what? I work on hamstring strength alot to prevent quad/ham imbalance- what other muscles connect to the knee?

I'm assuming he's meaning when most of the calf and thigh are touching (all the way down to the ankle on the calf) rather than just the top bit by the knee. That in a sit spin is a bit of an ugly position in my books, rather than the classic sit position (even if the ISU just made it slightly lower, it's still not ass on heel low).

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Re: Query About Knee Health
« Reply #20 on: September 27, 2010, 11:50:02 AM »
Did the orthopedist take into account the heel and blade stanchions on figure skates, or was s/he just talking about general off-ice squats in exercise shoes?  Figure skates have heels to allow that range of motion and to put weight on the forward rocker.  That's one of the reasons many coaches recommend wearing shoes with higher heels or putting heels on a thick exercise mat for off-ice sit spin exercises.  
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Offline kssk8fan

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Re: Query About Knee Health
« Reply #21 on: September 28, 2010, 11:24:35 AM »
deep knee bends are not bad if you have the necessary strength and flexibility.  most athletes are more than capable performing this maneuver if they have been conditioned properly.   The problems come into play when the person does repetitive knee bends without the proper opposing strength exercise.   Doing anything repetitive will eventually wreck havoc without balancing out the training.   Strong hamstrings, glutes and shin muscles can help with deep knee bends.   A trained plyometrics instructor would be more knowledgeable in this area.

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Re: Query About Knee Health
« Reply #22 on: October 02, 2010, 09:43:12 PM »
Isk8NYCFrom what I understand, the levering only happens when you try to touch your rear end to your heels with in a deep squat.  I can't imagine doing that in figure skates because you have to be up on your toes somewhat or you will fall backwards.  On the ice you would be on your toe picks.  I was responding to issues with doing very deep knee bends.

One source:
"The primary danger to the knee occurs when the tissues of the calf and thigh press together altering the center of rotation back to the contact area creating a dislocation effect. The danger of knee injury in this situation may be prevented if either of the following factor are present:

    * center of gravity of the body system is keep forward of the altered center of rotation
    * muscles of the thigh are strong enough to prevent the body from resting or bouncing on the calves. "

http://www.exrx.net/ExInfo/Squats.html

Some sites I use:
http://www.nureyev-medical.org/
http://www.sportsinjuryclinic.net/
http://www.aafp.org/afp/2003/0901/p907.html
http://www.usfsa.org/Story.asp?id=40699
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2370412/pdf/canfamphys00364-0064.pdf
http://scohenlmt.livejournal.com/16343.html

Offline Doubletoe

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Re: Query About Knee Health
« Reply #23 on: October 20, 2010, 08:13:40 PM »
For what it's worth, a few years ago I started having problems with my left knee from doing too many sitspins and axels.  Fortunately, I went to a very good physical therapist who was also a figure skater.  She measured my relative quad vs hamstring strength and determined that my quads were over-developed and hamstrings were under-developed (a very common problem for skaters), causing an uneven pull on the knee.  In addition to prescribing hamstring strengthening exercises and limiting the number of sitspins I was allowed to do for awhile, she told me I should go down to at least parallel (i.e., thigh parallel to the ice, per ISU sitspin guidelines) because that is the point where the hamstring muscles take over from the quads.  So although it may have been counter-intuitive, in this case, lower was deemed better.

By the way, I think it makes a huge difference that we do this deep knee bend with our weight forward on the ball of the foot and the heel lifted, which is what you would do in a sitspin.  It's a different dynamic--and much less strain--than trying to do a deep knee bend with the heel flat on the floor.

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Re: Query About Knee Health
« Reply #24 on: November 07, 2010, 01:46:23 AM »
Isk8NYC From what I understand, the levering only happens when you try to touch your rear end to your heels within a deep squat.  
I can't imagine doing that in figure skates because you have to be up on your toes somewhat or you will fall backwards.  On the ice you would be on your toe picks.  I was responding to issues with doing very deep knee bends.

One source:
"The primary danger to the knee occurs when the tissues of the calf and thigh press together altering the center of rotation back to the contact area creating a dislocation effect. The danger of knee injury in this situation may be prevented if either of the following factor are present:

    * center of gravity of the body system is keep forward of the altered center of rotation
    * muscles of the thigh are strong enough to prevent the body from resting or bouncing on the calves. "

http://www.exrx.net/ExInfo/Squats.html

Some sites I use:
http://www.nureyev-medical.org/
http://www.sportsinjuryclinic.net/
http://www.aafp.org/afp/2003/0901/p907.html
http://www.usfsa.org/Story.asp?id=40699
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2370412/pdf/canfamphys00364-0064.pdf
http://scohenlmt.livejournal.com/16343.html
THANK you so much for sharing :) these resources...