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Journals Supporting A2G Squats?

I’ve been trying to find journals that have studied the shear force on the tibiofemoral joint during 90 degree squats as compared to full squats. So far no luck. If anyone can help I’d appreciate it.

Hmm, can’t say I have any.

This is one to the contrary actually: forum.bodybuilding.com/showthread.php?t=6379361

I think the references would be more useful than anything- design in squat studies is notorious for problems; anything from low bar v. high bar, free v. smith machine, depth, form, etc.

look through some of the articles posted here about ATG squats and check out their references.

[quote]Neospartan wrote:
look through some of the articles posted here about ATG squats and check out their references. [/quote]

I’ve been looking.

[quote]tveddy wrote:
Neospartan wrote:
look through some of the articles posted here about ATG squats and check out their references.

I’ve been looking.[/quote]

anyluck???

no, I can’t find any references

I remember trying to do some quick searches on pubmed but not finding any supporting articles. There are, of course, a few older references that suggest they’re more hazardous to your knees (which we now know is mostly untrue). Evidence supporting ATG squats is more anecdotal than scientific from strength coaches and physical therapists.

Thats what I was afraid you were going to say. My biomechanics prof and I were argueing the subject though, So I’m still hoping to find something.

I’m by no means an expert in the field, but I suspect there is a reason there is little scientific data in this area. Probably because its true that the shearing forces on the knee are greater at a deep squat compared to an above parallel squat. However, this doesn’t necessarily mean a deeper squat is more hazardous to the knee.

A deeper squat will utilize more of the musculature surrounding the knee joint in order to stabilize it which will by default be protective to the joint. Further, to what degree the increased shearing forces are actually damaging to the joint aren’t very conclusive (at least in any of the articles I’ve read). I also wouldn’t be surprised that utilizing a full range of motion and flexibility required for deep squatting would be protective to the tendons and ligaments stabilizing the knee.

Thats the best reasoning I could come up with, I know there must be some exercise physiologists who can do better than my pure speculation. Really I think the most convincing evidence that ATG squats aren’t as dangerous as they’re perceived is the population of former olympic lifters. You would certainly see an epidemic of aging OL’ers with knee problems.

I think you’re going have a really hard time finding research that would compare full squats to partial squats or full squats as a safer activity.

From my research, there are a few journal articles that have applied force to cadaver knees at various angles, and they actually found that the greater the angle, the stronger the joint is when force is applied. They actually made a point that 90 degrees of flexion was the weakest point in the knee joint and that ironically is the point where most doctors say to squat to.

From a sheer force perspective however, if the hip joint is below the knee joint, there can’t be a sheer force on the knee joint. A sheer force works downward at an angle, so if the hip is below the knee, there can’t be a sheer force moving upward toward the knee. I don’t think you need any article or research to figure that out though.

This might help:

ATG better for the knee because ur not stopping the motion half way, so the knee does not sheer nearly as much, parrallel u have to stop and grind with the knee

The question is are you flexible enough to do it and have strength in that position? If not, start working on it and it will be just as safe as a below parallel squat once both strength,flexibility, and mobility are increased in that area.

[quote]bballsavant wrote:
This might help:


[/quote]

That did help. thank you.