I was thinking of using them to improve shoulder/upper back stability, while improving my ability to be more upright. I currently cannot squat unloaded and by very upright without holding on to something. Much like using the front squats currently as a range extender/mobility assistance exercise, i was wondering if OH would be good for addressing the points i mention.
The aim is strong legs not big legs, obvisouly they will get bigger and i am fine with that but str > size for me, and for that i have my staple low bar back squats, throw in the split squats and band squats, and i am happy with that work for development.
Yes to that, then.
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Be prepared for some fun adductor DOMS as you do this.
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Get used to big hamstring, rec-fem, groin stretching, and work on some external hip rotation (KStar's hip opener-ish).
I would also start doing shoulder dislocations with a barbell, too, This will open up your chest (pecs) and give you a feel for what the load will be doing.
When you do them, imagine bending the bar down, too, to get your lats involved. Without them, you're on a hiding to nowhere.
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Also, make sure you get fractional plates under your heels.