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  #1  
Old 02-13-2003, 03:25 AM
Morpheus Morpheus is offline
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are deep knee bends a good exercise?

I vaguely recall something about deep knee bends being too stressful on the knees. Is this true?
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  #2  
Old 02-13-2003, 04:17 AM
AskNott AskNott is offline
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You are fortunate, Morpheus. This is something many of us did not learn until after we wrecked our knees. It's useful to fully bend the knee during stretches, but not under load. Do half knee bends.
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  #3  
Old 02-13-2003, 06:59 AM
raygirvan raygirvan is offline
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No cite, but yes: the advice these days is when doing load-bearing knee-bend exercises, never let your knees bend tighter than 90 degrees (and some versions even say 110 degrees).
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  #4  
Old 02-13-2003, 08:48 AM
Epimetheus Epimetheus is offline
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This question comes up quite a bit and I always see the "bad on the knees" folks spouting their answers without much of any explination or evidence.

Bending your knees repeadedly is bad on your knees(like for a job or something). Proper form, good rest and nutrition deep knee bends, or weighted knee bends (squats) strengthen the muscles and tendons that support the knee. It is bad technique and abuse that cause injuries. It only stands to reason that if the muscle that supports the knee is stronger, the knee is stronger. Duh.

I have been doing Olympic style squats for quite some time now. Previously I could not even run for 100+ feet because of my knee problems that I got in the Marines. (Torn meniscus, Ligament tears) Now I can run for as long as my lungs hold out due to my new stronger and better knees.

No, deep squats do not cause your knees to go bad. It is a myth and I daresay that nobody will ever cite a study to back it up. Stronger knees are better knees and putting the muscles through the full range of motion makes them stronger than going half ass.
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  #5  
Old 02-13-2003, 09:57 AM
ultrafilter ultrafilter is offline
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With proper form, squats are good for your knees. See this article for a full explanation.
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  #6  
Old 02-13-2003, 12:41 PM
Fuel Fuel is offline
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I have had a couple discussions about this over the years. It depends on a couple of things:

1) How are you built? The distance between the different bones and cartilage make a huge difference. Do you have any muscle asymmetry?
2) How in shape are you? Are you flexible? Are your tendons and ligaments strong but supple? Are you proportionally strong in all muscles involved?
3) Will you use perfect form on every rep of every set of deep squats, every workout for the rest of your life?
4) Will you give your connective tissue enough time to adapt to the new loads? muscle adapts much quicker than does tendons.

Since these things can never be perfectly ascertained, the answer is it's basically not safe. However, if you know what to feel for (pain), have some x-rays and MRI's done, are in shape and know good form and are risk averse, you can do them.

Summary: Most people that injure themselves doing deep squats did something wrong. For me, i went too heavy too early and used my knee too much outside the weight room (mountain biking). I also wasn't flexible enough and did ignore a small pain too. i say try them out..... it's worth it, but be responsible. THere is no replacement for full ROM.
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  #7  
Old 02-13-2003, 12:42 PM
Fuel Fuel is offline
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whoops, i meant to say in the 3rd paragraph that it is safe.
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  #8  
Old 02-13-2003, 01:25 PM
FranticMad FranticMad is offline
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My experience is that your muscles need to be strong before you do deep bends with weights. The idea is that you want your muscles to be doing all the work in supporting your weight, not to relax and let the other things (ligaments etc) take more than they can handle.

I agree that damage comes from using too much weight, too early in training. My belief is that it takes time to strengthen all the little muscles that contribute to the overall balance and support. As well, it takes time for the brain and peripheral nerves to build up good proprioceptive control, so that your brain is able to marshall all the relevant muscles in a coordinated movement.

You aren't just building muscle, but learning to coordinate muscles to work together.

IANAD

proprioception = the ability of the brain to sense limb position and muscles, and to control them.
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  #9  
Old 02-13-2003, 07:16 PM
raygirvan raygirvan is offline
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]Fuel
It sums up as: if your basic physical nature is to be a macho side of beef (or you have the application to become one) you'll be fine. For the rest of us, deep knee bends should be treated with caution. I can't be be arsed to look for cites, because you'll always get egotistical beefboys claiming "o its garbage because ive done a million squats since i was rambo". Just try a Google search on ["deep knee bends" damage] and you'll find plenty of sports and medical websites warning of the risk for the rest of us mortals.
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  #10  
Old 02-13-2003, 08:37 PM
Hermann Cheruscan Hermann Cheruscan is offline
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I've been lifting weights off and on for over 20 years now. The squat is my favorite exercise, and I always go below parallel. I've never had a problem with my knees, but thats probably because I squat only after my knees are fully warmed up. I also use a 2" by 4" board under my heels. I think the trick to avoiding knee injury is to only go as low as you feel comfortable.
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  #11  
Old 02-13-2003, 10:34 PM
Fuel Fuel is offline
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Important to keep in mind: when doing deep squats, one will typically have to lower the weight in order to do the movement. This can be thought of as MORE safe. The way I look at it is if you are not using full ROM, you will be using too much weight than what your joint should handle. It can be argued that only going partially down is more dangerous than full ROM.

I think form, rep speed and weight choice are much more important than anything else, for joint health.
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  #12  
Old 02-13-2003, 11:16 PM
ultrafilter ultrafilter is offline
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Quote:
Originally posted by raygirvan
]Fuel
It sums up as: if your basic physical nature is to be a macho side of beef (or you have the application to become one) you'll be fine. For the rest of us, deep knee bends should be treated with caution. I can't be be arsed to look for cites, because you'll always get egotistical beefboys claiming "o its garbage because ive done a million squats since i was rambo". Just try a Google search on ["deep knee bends" damage] and you'll find plenty of sports and medical websites warning of the risk for the rest of us mortals.
And if you google on "magnetic insoles", you'll find plenty of websites that tout the benefits of those things. They're still junk.

Squats are safe, and they're good for your knees, if you do them right. You fuck up, you fuck up your knees.

See the article I linked to earlier as well as this page.
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  #13  
Old 02-14-2003, 10:48 AM
Fuel Fuel is offline
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raygirvan, we are all humans and have the same risk of getting a knee injury whether you are a beefboy or a mortal.

As for the search you suggest, you will find all the sites who are just too cautious, because whenever you get health advice from an official source, it will always be too cautious. If you get advice from guys like ultrfilter and I, it will be more realistic and unbiased. Talk to the big guys in your gym, they'll tell you about going what we call ATF. (ass to the floor..... not to be taken literally, that will get you a cast.) Just be responsible.
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  #14  
Old 02-14-2003, 11:23 AM
GOM GOM is offline
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Quote:
Originally posted by Fuel
1. Important to keep in mind: when doing deep squats, one will typically have to lower the weight in order to do the movement.

2. It can be argued that only going partially down is more dangerous than full ROM.

1. When you say "lower the weight" do you mean hold the weight in a different position, or reduce the amount of weight you are lifting.

2. Got any stats to back up that argument?

Deep knee bends, like many other things in life, are not always bad but they are not always good either. What kind of condition are you in now Morpheus?
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  #15  
Old 02-14-2003, 11:25 AM
GOM GOM is offline
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Sheesh. Make that a question mark after my first question....
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  #16  
Old 02-14-2003, 11:27 AM
ultrafilter ultrafilter is offline
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By "lower the weight" Fuel means "use less weight".
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  #17  
Old 02-14-2003, 12:45 PM
Fuel Fuel is offline
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Quote:
Originally posted by GOM
1. When you say "lower the weight" do you mean hold the weight in a different position, or reduce the amount of weight you are lifting.

2. Got any stats to back up that argument?

Deep knee bends, like many other things in life, are not always bad but they are not always good either. What kind of condition are you in now Morpheus?
Here's an article posted by someone on musclemag.com...... it's too bad there was no cite, but it will help get a point across better than i could:

"Squatting to parallel (legs bent 90 degrees) not only makes the exercise less effective but, additionally, it increases the risk of injury. First of all, by not squatting the full range of motion, one doesn't maintain proper lumbosacral bodymechanics. When performing the squat movement, the sacrum undergoes a process known as nutation (it tilts forward, relative to the two ilia on either side of it). At approximately 90 degrees of knee bend, the sacrum tilts back (a process known as counternutation) and sets the lifter up for lower back pain.

In order to perform a full squat, flexibility and range of motion must be maintained in the lumbar spine and SI joint, as well as in such muscles as the iliopsoas and hip external rotators—piriformis, gemelli, etc. If the lifter can't squat past 90 degrees of knee bend without the heels raising or the body bending excessively forward at the waist, but can squat all the way to the floor while holding onto something, we know that there are some muscle imbalances in regard to the pelvis/lumbosacral region (iliopsoas, external hip rotators, erector spinae) as opposed to a knee or foot/ankle dysfunction.

Additionally, since the hip joint is considered by many authors as the "steering mechanism for the leg," improper pelvis, hip, and lumbosacral mechanics could manifest down the kinetic chain as chronic or recurring knee/ankle problems. Thus, regular performance of the full squat offers a "screen" for the athlete of his or her lumbosacral/pelvic flexibility, which may prevent injury or muscle imbalances long before they become chronic.

Parallel squats also may be potentially damaging to the knee joint. The original data on full squats causing ligament laxity was obtained in an uncontrolled manner. Recent attempts to replicate these studies haven't shown any increased laxity or knee pain/dysfunction from doing full squats as opposed to parallel squats.

Furthermore, ask any orthopedic surgeon at what degree of knee bend does one perform the Drawer test—90 degrees. Why? Because in this position, the knee joint is the most unstable, and if you were trying to assess the integrity of the cruciate ligaments, you'd want the least amount of interference from other structures as possible. Bend the knee to full flexion. How much does the tibia move on the femur anteriorly or posteriorly? Very little. However, do the same test at 90 degrees of flexion, and you'll get considerably more movement.

Therefore, you can imagine how much force is on the knee ligaments if the athlete is descending with a weight on their shoulders, and then at 90 degrees—the most unstable point—reversing the momentum and accelerating in the exact opposite direction. Couple this with the fact that most, if not everyone, are capable of squatting considerably more weight to the parallel position than the full squat position, and you've set your body up for muscular imbalances, yet again."

Summary: working any movement in partial ROM while approaching failure is dangerous.
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  #18  
Old 02-14-2003, 12:54 PM
ultrafilter ultrafilter is offline
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The author of that article sounds a lot like Fred Hatfield, the guy who wrote the first article I linked to.
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  #19  
Old 02-14-2003, 01:04 PM
Dr_Paprika Dr_Paprika is offline
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I did my honours engineering thesis on knee biomechanics under a leading expert in the field. Articles in Muscle Mag and by "Dr. Squat" have less scientific credibility than peer-reviewed journal studies....

Quote:
Escamilla, R.F. Knee biomechanics of the dynamic squat exercise. Medicine and Science in Sports and Exercise, January 2001.

Purpose: Since a strong and stable knee is paramount to an athlete’s or patient’s success, an understanding of knee biomechanics while performing the squat is helpful to therapists, trainers, sports medicine physicians, researchers, coaches and athletes who are interested in closed kinetic chain exercises, knee rehabilitation, and training for sport. The purpose of this review was to examine knee biomechanics during the dynamic squat exercise.

Methods: Tibiofemoral shear and compressive forces, patellofemoral compressive force, knee muscle activity, and knee stability were reviewed and discussed relative to athletic performance, injury potential, and rehabilitation.

Results: Low to moderate posterior shear forces, restrained primarily by the posterior cruciate ligament (PCL), were generated throughout the squat for all knee flexion angles. Low anterior shear forces, restrained primarily by the anterior cruciate ligament (ACL), were generated between 0-60° knee flexion. Patellofemoral compressive forces and tibiofemoral compressive and shear forces progressively increased as the knees flexed and decreased as the knees extended, reaching peak values near maximum knee flexion. Hence, training the squat in the functional range between 0-50° knee flexion may be appropriate for many knee rehabilitation patients, since knee forces were minimum in the functional range. Quadriceps, hamstrings, and gastrocnemius activity generally increased as knee flexion increased, which supports athletes with healthy knees performing the parallel squat (thighs parallel to ground at maximum knee flexion) between 0-100° knee flexion. Furthermore, it was demonstrated that the parallel squat was not injurious to the healthy knee.

Conclusions: The squat was shown to be an effective exercise to employ during cruciate ligament or patellofemoral rehabilitation. For athletes with healthy knees, performing the parallel squat is recommended over the deep squat, since injury potential to the menisci and cruciate & collateral ligaments may increase with the deep squat. The squat does not compromise knee stability, and can enhance stability if performed correctly. Finally, the squat can be effective in developing hip, knee, and ankle musculature, since moderate to high quadriceps, hamstrings, and gastrocnemius activity were produced during the squat.
In English? Doing any squat will put stresses on your knee ligaments, but healthy knees can stand this. Doing deep squats will put comparitively more force on the back of your kneecap (PFJR) and between the bones in the top and bottom of your leg (tibiofemoral force). If you have knee problems, a bigger bending angle is bad. The benefits of going below 90 degrees may be outweighed by risk of injury if the weights involved are large.
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  #20  
Old 02-14-2003, 01:37 PM
Fuel Fuel is offline
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You know, I remember some discussions I have had on this topic and some people, including the article I posted, don't realize that 90 degrees is almost full ROM for some people, especially people with big legs. Hear me out.

The average person has a certain range of motion, until the hammy hits the calf near the knee joint. This is what I consider full ROM, which happens to be about 100-105 degrees for me. (remember that the shape of your leg makes the angle look much steeper, the bones are at 90 degrees and the leg looks like about 100-110). Even though my legs can move an additional 30 degrees together, the reason I say that this point is full ROM is that once you touch these areas together, it creates a lever that prys your knee joint apart. While toting 300+ lbs., this is seriously dangerous. For skinnier athletes, their point of touching is more around 120 degrees.

So, in light of that article, I say 90 degrees squats are good, but full ROM is better and healthier in every way, assuming you are in shape and use good form. Try to go hams to calf.

I welcome your comments on this, Dr. Paprika, you have done much more reading and research than I.
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  #21  
Old 02-14-2003, 01:40 PM
Fuel Fuel is offline
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Keep in mind that the true answer to this question is very subjective to the individual. That's why I myself go 100 degrees, whereas I tell my skinny but athletic workout partner to go farther down.
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  #22  
Old 02-14-2003, 02:09 PM
Rucksinator Rucksinator is offline
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Quote:
Originally posted by Hermann Cheruscan
... I also use a 2" by 4" board under my heels...
Why the 2x4?

- Guy just getting back into weight lifting, this time without the benefit of his HS football coaches' supervision
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  #23  
Old 02-14-2003, 03:34 PM
Fuel Fuel is offline
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Quote:
Originally posted by Rucksinator
Why the 2x4?

- Guy just getting back into weight lifting, this time without the benefit of his HS football coaches' supervision
Consider yourself lucky that you are not under the supervision of a HS football coach. (for the most part, no offense)

the 2x4 is usually suggested for taller individuals. It's meant to keep them from having to bend the knee forward past the feet. I'm not sure of the implications of doing this, but I would assume it's perfectly safe, especially for people who have a hard time with knees going past feet.
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  #24  
Old 02-14-2003, 05:11 PM
Hermann Cheruscan Hermann Cheruscan is offline
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The 2x4 does help me keep my balance. It also seems to throw more of the exertion on my quads rather than my glutes.

I once had a training partner who always did his squats flat footed. I did them the same way for a while, even getting rather good doing them that way. The only thing was, my glutes would be more sore than my quads. And then my ass started getting too big, so I started using a 2x4 again.
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  #25  
Old 02-14-2003, 05:59 PM
GOM GOM is offline
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:::: ponders asking a question ::::

hmmm

:::: decides to take the path of wisdom, this time ::::

__________________

Then you will know the truth, and the truth will set you free.

- Jesus -
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  #26  
Old 02-14-2003, 11:57 PM
Epimetheus Epimetheus is offline
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Quote:
Originally posted by Dr_Paprika
I did my honours engineering thesis on knee biomechanics under a leading expert in the field. Articles in Muscle Mag and by "Dr. Squat" have less scientific credibility than peer-reviewed journal studies....


Not to discredit your thesis or the person you worked under but this is the silliest thing I have heard.
I agree with you about the articles in muscle mag, though discrediting them just because the are in a bodybuilder magazine is folly. Childish as well. It is an ad hominem attack, a logical fallacy if your engineering degree taught you anything. As for Dr. Squat- sure the name sounds goofy, but look at his credentials. Yes, I am aware that this is the appeal to authority fallacy, but I figured since you were being fallicious I might as well also.

Lets see, whom to believe. You- with a P.E I am assuming. Or a Dr. of sports science. Phd. with well, lets see what the cite says about Dr. Squat.

Quote:
In college, he competed in gymnastics, and was team captain in his senior year. He competed in the National (NCAA) Gymnastics Championships three consecutive years as a college gymnast, and was the SCSU charter president of the National honorary athletic fraternity, Sigma Delta Psi. He graduated with honors in 1969, earning his Bachelor of Science degree in health, physical education & recreation.
Quote:
Following graduation, he accepted a teaching fellowship at the University of Illinois at Champaign/Urbana, earning his Master of Science degree in the social sciences of sport. His doctoral studies at Temple University (Philadelphia) were completed during his tenure there as a teaching associate. His doctoral competency examinations were successfully completed in the social sciences of sport (psychology, sociology and motor learning). He was awarded his doctorate (Ph.D.). degree in 1973.
Quote:
accepted a professorship at the University of Wisconsin (Madison) in 1976, where he conducted research in sport psychology and taught undergraduate and graduate level courses
Quote:
In 1983, Dr. Hatfield studied for a brief time at the famous Lenin Institute of Sport in Moscow (USSR). He returned there in 1989 as co-coach of Team USA for powerlifting competitions in Moscow and Abakaan, Siberia. He has four training books translated into Russian, distinguishing him as one of the best known Western strength experts in the Soviet Union.
Quote:
Dr. Hatfield advanced to the position of Senior Vice President of Weider Health & Fitness, Inc. by 1989, and was director of research and development for that corporation until June, 1991.
Quote:
In 1991, Dr. Hatfield was awarded the prestigious Alumni Citation Award from Southern Connecticut State University "in recognition of [his] extraordinary achievements and distinguished career."
And the list goes on. Quite a long and sucessful career. A leading expert in the field, and has apparently been one for several decades. Not to mention he puts his science to practice.

So, whom to believe. A guy on the internet we know nothing about that claims to have a thesis that says squating is bad on the knees, and a leading expert that says doing squats wrong is bad on your knees but doing them right helps the knees. I think I will believe the expert. He seems to have a track record that I can check up on. You don't.

Thanks for the post though. So sorry you only find peer reviewed journals credible. When I am 80 and my knees are going strong I will remember your article on how squats screw up knees.

This from a guy that has a medical discharge from the military due to knee injury. Squats bad for you knees indeed.
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  #27  
Old 02-15-2003, 12:05 AM
Epimetheus Epimetheus is offline
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I missed the Dr. Part of your user name. Oh well, ignore the engineering part of my post.
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  #28  
Old 02-15-2003, 12:22 AM
Fuel Fuel is offline
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That article I posted was not a part of Musclemagazine, it was an unrelated article posted on musclemag.com by a user on the forum. I WOULD NEVER POST ANYTHING OUT OF MUSCLE MAG!
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  #29  
Old 02-15-2003, 12:36 AM
Epimetheus Epimetheus is offline
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http://www.ironmagazineforums.com/sh...p?threadid=437

A good article by Lyle Mcdonald on the trend towards demanding peer reviewed studies and etc.

It is funny how a strength trainer can have 30 years actual experience in training countless athletes in the top of their sport says "doing such and such has this result" and some pedant comes along and say "but there is no studies showing this to be true". How about 30 years experience? Studies smudies. (only teneously related to the knee thing I know....)
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Old 02-15-2003, 12:12 PM
Dr_Paprika Dr_Paprika is offline
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Now don't be an idiot, Epimetheus. You clearly did not read my post, and jumped to all sorts of silly conclusions.

Quoted by Epimetheus
Quote:
So, whom to believe. A guy on the internet we know nothing about that claims to have a thesis that says squating is bad on the knees, and a leading expert that says doing squats wrong is bad on your knees but doing them right helps the knees. I think I will believe the expert. He seems to have a track record that I can check up on. You don't.
While I have squatted for ten years, I do not claim to be an expert in squatting, nor was my thesis on squatting. I did not say squatting was unsafe. The article I quoted did not say sqautting was unsafe. So don't be a friggin' moron.

Dr. Squat and the article I quoted are saying the same thing. I want you to read that again, slowly, and saying all of the difficult sounds out loud. I really could care less what some self-righteous punk believes, Epimetheus, but these are the facts.

The fact is that there is a lot of twaddle and pseudoscientific bullshit about weightlifting around, including many articles in magazines such as musclemag, etc. This does not mean that they cannot have good articles, but many "articles" in such magazines are clearly unscientific or shallow advertisements for dubious products, etc. Few articles in AJSM advertise Hydroxycut.

The fact is, that in any field, the opinion of one or two experts adds up to a relatively low degree of credibility, regardless of credentials. Experts, even those who use phrases like "you gotta", are often wrong. The biomechanics of the knee are far less well understood than you think, both in vivo and as mathematical models.

While I agree there is a danger in requiring studies for everything, they do give a lot of useful information. In addition to clearing up ignorance, they can show cause-and-effect, and they can suggest which side of the debate is right. Perhaps you should learn more about the value of a good study. No one is denying that experience is helpful. But if a well-conducted study does exist on the relavant topic, it would be foolish to simply ignore it because it contains big words one finds "pedantic".

Twenty years ago, orthopedic surgeons with thirty years experience recommended removing the meniscus (cartilage) from arthritic knees, based on a lifetime of experience. The meniscus was thought to be relatively useless. In fact, it is now known to act as a shock absorber, and is extremely important in healthy knees. Surgeons now do everything they can to preserve the meniscii. These are the structures that may be damaged by doing deeper squats. But no one really knows. These surgeons have many impressive credentials, as does Dr. Squat. Mine are more modest - an honours gold medal winning biomechanical engineer and a medical doctor who did research with several orthopedic surgeons (with more impressive credentials, IMHO) than Dr. Squat. But none of these people fully understand the knee. Nor do I. Neither, may I say so, do you.
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  #31  
Old 02-15-2003, 12:23 PM
Dr_Paprika Dr_Paprika is offline
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And thanks for finding that article. It is, indeed, "a good writing", which lends much support to your "arguments". Much good writing comes from ShitDisturber(TM).

Unfortunately, as the one person who commented on his confused polemic said, the author does not understand the scientific method. Nor does he understand the basic statistical techniques he discusses. I agree it can be dangerous to rely only on studies. I agree no "ideal workout" exists. I don't think such a workout would be the same for two different people, or the same person at different periods of time. Statistics can be manipulated, but not by the extent the author believes. Some studies can indeed show cause and effect. Good studies have ways of showing the reader that the statistics were not manipulated in an unacceptable manner, although this is not foolproof. Nor proof from you.
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  #32  
Old 02-15-2003, 12:34 PM
Epimetheus Epimetheus is offline
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Now now, no need for insults. This is hardly for forum to be calling me an idiot and a punk.

I also never claimed to be an expert on knees. Nobody can be an expert on everything so sometimes we have to rely on the statments of other experts. The only thing I can do is rely on judgement of what others that know more than me say. Bring up a contrary opinion of another expert to somebody else claiming to be an expert is not the same as claiming to be an expert themselves. Sorry you feel that way. Of course a cool headed expert tends to hold more weight to me than somebody whom childishly insults dissenting views. But I am just a self righteous punk so my opinion doesn't matter. I am sure you feel the same way about the other people viewing this thread making their own judgements as well. After all, they don't have near the credentials you do, so who are they to say otherwise. Pah, whatever.
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  #33  
Old 02-15-2003, 12:58 PM
Epimetheus Epimetheus is offline
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Quote:
Originally posted by Dr_Paprika
Experts, even those who use phrases like "you gotta", are often wrong.

Obviously the guy isn't writing for a scientific journal, he is writing for a specific audience. Use too many fancy words and "proper" pedantic babble and you lose the audience he is trying to educate. Audience targeting. Remember that the next time you feel the need to try to discredit somebody on how they write their articles. Not everybody has the luxury of being blessed with remarkable intelligence and wonderful parents that can help pay the way through 8-9 years of school so they can be called Doctor. In that case the person teaching has to find a way to teach them without the students falling asleep.
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  #34  
Old 02-15-2003, 01:03 PM
Fuel Fuel is offline
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Quote:
Originally posted by Fuel
You know, I remember some discussions I have had on this topic and some people, including the article I posted, don't realize that 90 degrees is almost full ROM for some people, especially people with big legs. Hear me out.

The average person has a certain range of motion, until the hammy hits the calf near the knee joint. This is what I consider full ROM, which happens to be about 100-105 degrees for me. (remember that the shape of your leg makes the angle look much steeper, the bones are at 90 degrees and the leg looks like about 100-110). Even though my legs can move an additional 30 degrees together, the reason I say that this point is full ROM is that once you touch these areas together, it creates a lever that prys your knee joint apart. While toting 300+ lbs., this is seriously dangerous. For skinnier athletes, their point of touching is more around 120 degrees.

So, in light of that article, I say 90 degrees squats are good, but full ROM is better and healthier in every way, assuming you are in shape and use good form. Try to go hams to calf.

I welcome your comments on this, Dr. Paprika, you have done much more reading and research than I.
Dr. Paprika, could you comment on this post? Does this line of thinking mesh well with what you have seen in your research? I would propose that the reason the pressures go up so much in the "functional" ROM is because of this lever effect. Is this true?
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  #35  
Old 02-15-2003, 09:55 PM
Dr_Paprika Dr_Paprika is offline
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I did go too far in calling you a punk. But it shopuld have been clear the article I quoted was generally agreeing with Dr. Squat. I was pretty cavalier in making fun of his use of "gotta" and his name, which I agree are irrelevant. I think some of the comments in your first post were also cavalier.

I have not researched squatting specifically, although I am an avid weightlifter. My research involved angles of knee bending, but not under those sorts of loads. You are quite correct in assuming that functional pressures are high due to the lever effect. IIRC, these loads can be as high as seven times body weight when climbing stairs WITHOUT additional load. When not squatting, a lot of the force is between the kneecap and the femur. If squatting 300 lbs, obviously the tibiofemoral component is greater than if squatting body weight only, but probably lessened if the lifter does use a two by four (which changes the practical direction of the reaction force to counteract gravity).

The theoretical ROM limit is, according to the excellent Clinical Orthopedic Examination 135 degrees for the knee, limited when the heel touches the buttock. I agree that close to this angle (like the ones you mention), the lever would place heavy forces on the knee fibrocartilage (meniscus), damaging it in some people. But I don't think anyone knows that it definitely leads to damage in people with healthy knees.
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  #36  
Old 02-15-2003, 10:02 PM
Dr_Paprika Dr_Paprika is offline
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Hmmm, maybe I didn't go too far in calling you a punk, either. You called me childish, told me my reasonable comments were the silliest thing you ever heard, told me I was being fallacious (e.g. lying) and claimed I only found peer reviewed articles credible (when I merely said they were more credible than Musclemag, which I think most people would agree with). I did not make most of the claims you argue against.

Incidentally, researchers often choose a topic they are interested in -- the people who do this sort of research tend to be pretty avid athletes themselves. Many of their trials involve weightlifters and professional athletes. I think your citation is a little off base here.
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  #37  
Old 02-16-2003, 12:02 AM
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Dr. Paprika, so what do you think is the difference, pressure-wise, between squatting until parallel and squatting until hams touch calf? At what angle does the pressure intensity spike upwards? Does this angle correspond with the angle at which the ham touches the calf for the individuals you tested?

I am trying to get as close to this pressure point as possible, to take advantage of the fullest safe ROM possible for maximum fiber recruitment. Surely your research logs could answer this question.....

Hey, you guys drop it and let's pump some good, useful info into this post. There is a place for technical facts and a place for experiential facts, let's use both.
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  #38  
Old 02-16-2003, 03:31 PM
Dr_Paprika Dr_Paprika is offline
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I quite agree.

The knee is a very complicated structure. Two-dimensional models of the knee (hinge models) do not usually give results all that similar as those experimental studies -- the centre of gravity of the knee, the position of the kneecap, and the direction of the involved leg muscles change with flexion angle. Even how you measure the knee flexion angle differs between papers, although the best ones simply have angle sensors on both the calf and thigh. So you're better off using sensors and simulating what you want to measure than just using free body diagrams.

The research on this question is far from complete. This site summarizes the earlier article well.

http://www.sportsinjurybulletin.com/...-the-squat.htm

This article

http://asme.pinetec.com/bio2001/data/pdfs/a0097172.pdf

is more relevant to your question, but is based on a two dimensional model (which involves several simplifications), however the weights involved are realistic. It would seem to imply that the limiting factor is the force on the PCL which would shoot up sharply after 120 degrees. But again, they do not explicitly say just how they are measuring this angle (as you flex the knee, the calf moves forward, so I would say the ROM is less than 150 degrees).

Even the analysis of one of Dr. Squat's flunkies at:

http://www.drsquat.com/index.cfm?act...e&articleID=73

does not address depth of squat. Dr. Squat's research relies pretty heavily on the same paper I earlier quoted.

Given what is out there, I would say that above 90 degrees you are increased risk of damaging your menisus due to shear forces and above 120 degrees you are at risk of damaging your PCL in a healthy knee. But no one knows for sure, and all the engineering diagrams and technical facts in the world are not going to replace experimental studies, but I never claimed this to be true.

There is a lot of anecdotal evidence about squatting injuries. Nevertheless, I bleieve squatting to 90 degrees with good form is clearly safe. Going beyond ninety degrees would increase calf development (gastrocnemius and soleus muscles) and increase stress on lumbar muscle in the back. But these can also be approached with other exercises. Why take the risk of injury to go as close to the pressure point as possible, when it likely differs between two people? I just don't see the cost-benefit paying off.
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  #39  
Old 02-16-2003, 04:12 PM
Epimetheus Epimetheus is offline
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Quote:
Originally posted by Dr_Paprika
Hmmm, maybe I didn't go too far in calling you a punk, either. You called me childish, told me my reasonable comments were the silliest thing you ever heard, told me I was being fallacious (e.g. lying) and claimed I only found peer reviewed articles credible (when I merely said they were more credible than Musclemag, which I think most people would agree with). I did not make most of the claims you argue against.
No, fallacious (I spelled it wrong before) is not the same as lying, it is containing or based on a fallacy. Somebody that reasons something based off a fallacy isn't lying, they are just following a corrupted logical path. My claim that you found only peer reviewed journals credible was a hyperbole of your statment which insinuated that Dr. Squat was not a credible authority. It was not really intended to be taken literally.

I reflected on your statements that I am a self-righeous punk and I have to concurr and say that it is an unfortunate reality. I was a bit snarky as they say, and appologize. I should have been more civilized and more of a man and approached it with much more tact. I appologize for insults given and taken, intended or not, and hope that future confrontations will be much more civilized than what I haven given this time. Hopefully I will be much more educated on this subject if it comes up again, or have a bit more than indignation to fill my post up with. Untill then Doctor.
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  #40  
Old 02-16-2003, 06:20 PM
Fuel Fuel is offline
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Quote:
Originally posted by Dr_Paprika
I quite agree.

The knee is a very complicated structure. Two-dimensional models of the knee (hinge models) do not usually give results all that similar as those experimental studies -- the centre of gravity of the knee, the position of the kneecap, and the direction of the involved leg muscles change with flexion angle. Even how you measure the knee flexion angle differs between papers, although the best ones simply have angle sensors on both the calf and thigh. So you're better off using sensors and simulating what you want to measure than just using free body diagrams.

The research on this question is far from complete. This site summarizes the earlier article well.

http://www.sportsinjurybulletin.com/...-the-squat.htm

This article

http://asme.pinetec.com/bio2001/data/pdfs/a0097172.pdf

is more relevant to your question, but is based on a two dimensional model (which involves several simplifications), however the weights involved are realistic. It would seem to imply that the limiting factor is the force on the PCL which would shoot up sharply after 120 degrees. But again, they do not explicitly say just how they are measuring this angle (as you flex the knee, the calf moves forward, so I would say the ROM is less than 150 degrees).

Even the analysis of one of Dr. Squat's flunkies at:

http://www.drsquat.com/index.cfm?act...e&articleID=73

does not address depth of squat. Dr. Squat's research relies pretty heavily on the same paper I earlier quoted.

Given what is out there, I would say that above 90 degrees you are increased risk of damaging your menisus due to shear forces and above 120 degrees you are at risk of damaging your PCL in a healthy knee. But no one knows for sure, and all the engineering diagrams and technical facts in the world are not going to replace experimental studies, but I never claimed this to be true.

There is a lot of anecdotal evidence about squatting injuries. Nevertheless, I bleieve squatting to 90 degrees with good form is clearly safe. Going beyond ninety degrees would increase calf development (gastrocnemius and soleus muscles) and increase stress on lumbar muscle in the back. But these can also be approached with other exercises. Why take the risk of injury to go as close to the pressure point as possible, when it likely differs between two people? I just don't see the cost-benefit paying off.
Very helpful Dr. I got a couple extra-important things out of these articles by breezing through them:

1) Fatigue causes forces and pressures to increase.

2) The Quad (supposedly) does not work any harder after 90 degrees. Very interesting to hear that.

3) The forces in the graphs in the Adobe article spike upwards at 100 degrees.

Well, none of those articles addressed the issue of the hams-touching-calf-lever issue, as i figured. I wish they would address this, as it comes into play tremendously, i'm sure. The degree of the lever created no doubt has an impact on these shearing and compressing forces spiking upwards at said angles. I just wish I knew how much of an impact.

Was the Adobe paper yours? Were there large deviations in test results from person to person? Were the test subjects athletes or normal folk? Any other background info on that research would be nice.

It's so odd to hear these forces increase so drastically with deep knee bends. I mean, you can't even feel these forces. Thanks Dr. Paprika. I will be much more careful when decribing form to my training partners.
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  #41  
Old 02-16-2003, 06:24 PM
Fuel Fuel is offline
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What i meant to say is: Is there a correlation between the angles at which the forces increase and the angles at which the hams/calf lever comes into play? This is a question for anyone out there, not necessarily for just paprika.

Maybe it seems like I am making too big a deal out of this lever thing, but it would be helpful to know because you could just look at someone's legs and tell them what angles they should be bending to.
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  #42  
Old 02-16-2003, 08:17 PM
Dr_Paprika Dr_Paprika is offline
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I apologize to Epimetheus if my earlier replies seemed pompous.

I have never written a paper on squatting. The Adobe paper was not mine.

I do believe there is a correlation involving the hams/calf lever arm, like you suggest. I suspect it is not the limiting factor in picking the maximum angle of knee flexion, though. Depending how you measure the knee angle, this lever arm might be approximately proportional to the (positive number) difference between the sine and cosine of the knee flexion angle. But a difference of, say, ten degrees between 110 and 120 would probably be smaller than other changes on the knee due to the new direction of muscle forces because of the change in angle, forces on the meniscus and ligaments, etc.
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