squats vs leg press?

_Virtuoso_


Well there's a lot of conflicting theories and opinion when it comes to squats, such as which are the dominant muscles used, the primary muscles worked, when you should break etc. and even though some will say theoretically squats should stress the knees less, the evidence here says otherwise (in this case at least). Assuming, and all we can do is assume, that he has correct form - then if squats light or heavy kill his knees, then he obviously shouldn't be doing them despite what any squat science says.

It's not as much science as general physiology. I don't see how anyone can argue that squats aren't quad dominant. During the concentric contraction, you are demanding your hips become elevated to a somewhat "neutral" position with the exception of them being pulled back in order to maintain a centre of gravity (which is most commonly known as the level of your 2nd sarcral vertebrae) in order to maintain upright positioning and avoid the increased risk of following backwards and the way to execute this is extension at the knee, there's no other way to do so. You use hamstrings as eccentric stabilizers and antagonist stabilizers while your glutes and adductors would mainly act as synergists.

Hamstrings respond as agonists, or "concentric movers" to two movements. Extension at the hips, flexsion at the knee. During the squat flexsion at the knee occurs but it occurs during the eccentric contraction so it's with gravity and not during the concentric contraction when it's working against gravity. During the eccentric force, where knee flexsion occurs, gravity is the motive force and your muscles are the resistive force. You are resisting gravity. During the concentric contraction, when the muscles demand for maximal contraction significantly increases, then gravity becomes the resistive force and your body becomes the motive force. So you can eliminate hamstrings and glutes as being the concentric movers, rather than stabilizers VS. synergists.

As far as the OP goes, no one has seen his squat form so it would be for the least interest for someone to automatically assume he's squatting right - toes out, breaking parallel, hips/knees are breaking simultaneously, he's using force from his hips to assist the concentric contraction where his knees would take less stress and the hips would take more stress VS. a leg press where he would be isolated to a seat pressing the external load a 45 degree angle in relation to a 90 degree vertical angle (during a squat) where his adductors, hips, and posterior chain demand of stimulation increases with muscle groups utilized.

ACE-CPT, NASM-CPT, AFPA-Nutrition Consultant 

Well I really don't want to get into a debate about squat science because it would be very long and end up nowhere. To stay on topic though, it's really only general advice that can be given without a squat form video from the OP, however I think a long term knee injury, or any injury for that matter, should always be taken into account when handing out advice rather than just saying "your form is wrong". I'm sure, either way, by now the OP has likely checked his form and either corrected it, or if already correct decided to remove any exercise affecting that injury and replaced it with one he feels is less of a stress.

V,
    You're the Clipart Photoshop GOD!

 

The OP cannot correct his own form. If he's been doing it for so long I'm near positive to say he wouldn't be squatting with bad form for so long with acknowledgment of his own fault.

The only way it would be fully critiqued is if he provides us with a video of his form, when someone says they are withstanding pain during certain exercises (especially one of the top mass building movements), it's more for us to ask for a video of form than tell him to replace it with a machine.

I think we're in agreement that a video is the suitable suggestion.

ACE-CPT, NASM-CPT, AFPA-Nutrition Consultant 

Well when people question their own form, as I have often done, it's always handy to watch technique videos and then practice that form without weight, and then try and utilise it in your next session, especially seeing as the majority of gyms have mirrors in front of the racks/freeweights. So in that sense people can correct their own form.

V,
    You're the Clipart Photoshop GOD!

 

It's still hard to critique your own form and if he really wants to fix the issue, providing us a video with a lighter weight squat would be appropriate.

A properly performed squat is scientifically proven to be the easiest exercise on your knees.

ACE-CPT, NASM-CPT, AFPA-Nutrition Consultant