forgive me but I seem to have forgotten how to use google scholar, aka i cant find anything.
IMO, there's too much conflicting data out there for us to really care. I've read numerous studies showing drastic increases in glute activity as depth increases with only minimal increases in quad activity, from ~90 degrees and below.. which would only make sense to me.. though, all of this depends on so many intricate differences in squat technique, ie bar position, torso position, shin angle with the floor etc... if your knee drifts very far forward as you hit "ATGbro", it's going to be an insane amount of quad contribution... if your shin is completely vertical, quad contribution is going to be very minimal while you're trying to get out of the hole -> it cannot anatomically contribute more than glutes given the line of pull and weakness at that ROM.
none of this even matters to me though.. pick your tool, based on what feels most comfortable in terms of aches & pains, then go with it 100%.. if squatting ATG hurts your hip, well, fix your hip or squat slightly above parallel.. if ATG feels fine, go with it 100%.
increasing your half squat X % is going to increase your deep squat Y %, and vice versa.. If your half squatting isn't improving your deep squatting, then you're doing it wrong (probably squatting way too high). Your deep squat should obviously improve your half, but, to the extent of focusing on half squatting primarily? usually not.
I tried to find the video of me going 315 x 1 for decent speed singles below parallel at like 148-150.. it was a night video.. maybe i didn't upload it, but i remember i uploaded pics.. anyway, the point being: I hadn't squatted deep for pretty much a year, then after achieving 405 x 1 half, a few days later I felt like playing with below parallel squats and they felt really strong, 2xBW singles easy without ever focusing on them exclusively.
The issue of EMG is still a 'debate', so to is the effect of squatting in general at improving vertical jump. Conflicting material is everywhere. Some studies say squatting doesn't improve CMJ, some do. Some say going half is optimal, some don't.
The real meat of the issue is getting relatively stronger and being able to display that strength in a specific amount of time... so basically, Relative Power.
Studies like the one you just posted always bug me, especially when you consider the deep squatting 'cult' and their "agenda".
The comment about quad size is equally annoying.Do people with 'strong quad genetics' gravitate towards olympic lifting, or is it vice versa? Obviously people with strong quad genetics are going to do better at olympic lifting naturally. Why are we to credit their quad size to deep squatting when they spend countless time jumping with weight, catching weight, and pressing weight overhead in a variety of manners such as split jerk & squat jerk.
Professional body builders have bigger quads, let's credit leg extensions.
for the record, since im back to posting alot, im not anti deep squat whatsoever.. Again, pick your tool (half or deep) and improve it as much as humanly possible.
pC
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