Inhale before you unrack the weight and hold it.
Inhale before you unrack, hold it during walkout/setup, breathe, then inhale before you squat and hold it. You'll probably find various opinions on the subject, though.
I think it's allong the lines of if you hold your breath through the entire motion you will have more core stability thus lift more. But if you do your blood pressure goes through the roof.
What I do is breath out going up very small controlled breaths.
I'm ok with the concentric part of the lift as far as breathing goes. It's just the eccentric. I find that sucking in a big breathe before going down seems to work better than sucking in while going down. I was just curious as to which is better.
The former is what I always do. I think you risk not getting enough air in your lungs the other way.
I hate fake power racks that make you back out for half an hour before you have clearance to squat. In those situations I will walk out carefully, set my feet, fill my belly with air, push out on that air with my abs, and squat, holding the air the entire time.
The instability breathing would bring to your body with 540 pounds on your shoulders would play hell on your back.
Yeah, breathing ain't an option during the descent, that's for sure. I inhale, drop, and exhale on the way up as I straighten out.
Well, thanks for the help guys. Was able to pull off a PR yesterday, 375 (raw). Took in a big breathe before I went down, and exhaled only when I got a little stuck.