squat, breath at the top, squat, exhale at the top.
bench, same
deads, various ways, breath before grabbing the bar, lift, exhale at the top, inhale, lower weight, and lift again
or breath before grabbing the bar, lift, exhale, lower, inhale, lift.
breath before grabbing the bar because you can get more air in becausr you are not under pressure from the weight. breathin at the top can allow you to get mre air because you are upright, much like the squat. breathing at the bottom, your not under pressure but your in a squat possition. both have pros and cons