It's a question I ask myself every single day. If squatting too low is not necessary, then the classic bent-leg deadlift really should suffice for maximum quad stimulation because for me it really is a quarter squat with the weights held in front.
In fact, just like squat-built people find that their squat and deadlift are awfully close, I find that my regular deadlift and quarter squat are about the same.
The squat depth thing has always seemed arbtirary to me. The same guys who sceam "ass to grass or die, bitch!" (and I used to be one of them) and who poo poo the pigeons in the gym doing quarter squats and high-fiving each other are often the same dudes who give props to guys doing 1000-lb good mornings in a rubber band suit. The arguments about form seem to fly out the window when we talk about professional PL meets.
Yes, I know that PL squats and Oly squats are entirely different, apples and oranges, but it's really a case of a bunch of guys getting together and making up arbitrary rules about what depth counts on the basis of what allows one to handle the most impressive weight, win contests and generate interest in PL as a spectator sport.
Squatting too low is possible I suppose, but what counts as low depends on your build. Those stumpy-limbed folks tend to be able to go awfully far down without posterior rotation. I'm not convinced that taller or more long-limbed-to-torso folks should go down to the point where that rotation occurs. For me this is just a hair below parallel.
At that point my natural shitty leverages keep me from staying very tight, at least in a manner that allows me to demonstrate much strength. That position sucks for me and no matter how many squat-advantaged people tell me ass-to-the-floor or else, I may be better off by working intelligently within the limitations of physical characteristics that I cannot change. So maybe there is such a thing as too low for some of us and we would progress a lot further by staying a little high, i.e. parallel.
I have noticed that some inflexible people round their back as they go lower. Not everyone has the flexibility to go atg and keep a good arch in their back. I think that everyone should work on flexibility, even the flexible ones.
If you are squatting for fitness and not for powerlifting, I see it the opposite way. It is more important to work the depth than the weights. Flexibility and strength throughout the full range of motion is more "fit", in my mind, than a 700lb half squat. Of course, they aren't mutually exclusive.
Oh, and make sure to work both Oly and Power squats in that case.
I used to be one of those people who went "ass to grass" and now that my knees are very screwed up right now i am starting to reget it. However my injury was probly because of improper form (rookie mistake) But in terms of squats I have always found that 1 1/2 squats worked best for me.
well accept that by having the bar in front of you you are forcing your ass, hams etc to pull BACK against that load in front of you to balance the opposing force and a LOT less attention to the quads that simply have to stand up a bit. so thats like apples and oranges compared to a squat.
To Low?? Well if it HURTS, Not that its HARD or you STRAIN thats good if there is REAL pain thats to low for you. Or iff you fall on your ass LOL then you went to low. Also depends on your goals. are you a PLer, an olylifter, or just wana look goood nekid.
Hell even PL'ers can benefit from going LOW from time to time.
I did a lot of serious leg work for the last 4 months. Doing squats & deads more often than normal. After a while, just breaking parallel ended up causing tendon pain in my knees. For the last month I've been doing 1/4 squats and leg extension machine instead. My knees are getting better, but my deads and squat progress has slowed. I still load up the weights from time to time to make sure I still have my strength, but id imagine it will be a while before I can start increasing the intensity on a weekly basis. So I guess it depends on your frequency, intensity, form, genetics, etc. to know for sure how far down you should go.
For those who are interested by what I mean by "more often than normal" here is the routine that I speak of.
My deadlift and squat exercise frequency and intensity in the last few months were based on...
and before that I did a customized routine that consisted of leg press holds, squats and deadlifts for a short period to get my legs in shape for skiing. Followed by a 2-week break before starting in on CW's routine.
For me I go low to make sure I'm not cheating. If you're not going to go all the way down, I'd suggest box squats, that way you can be sure you went to the correct depth and aren't getting shallower with every weight increase. Based on what I've read, and how my knees feel, I think ATG squats are less damaging as well. (in my opinion this is because a mid squat reversal places additional torsional stress on the meniscus, but your milage may vary)
If you wanna hit the quads more do Zercher Squats. Basically a deadlift with the bar BEHIND you.
As for ass to the grass, before I messed up my leg, which is still recovering (2 fucking months without 'heavy' squats and deadlifts so far, it sucks); I would often alternate doing highbar olympic style ass to the grass squats and front squats, good mornings, upper range squats, lower range (at parallel) static holds, box squats (which has to be the single most awesome squatting tool known to man), front squats, and olympic lifts.
The point, do what YOU like, but keep it well rounded. Don't just do squats, do some posterior chain stuff too like GM's and DL's. Stay balanced.
Oh, and here's something I've learned the hard way. STRETCH.