Secondary muscles worked:
Anterior core (abdominals and obliques)
Erector spinae and multifidus (lower back)
Hip flexors
Rotator cuff (shoulder joint supporting musculature)
You also have the muscles around each of the joints, which is basically means all the rest of the upper body.
If you're interested in purely bench, you could work on each one.
Personally, I'd try doing an (upto) 120% static hold on the bench which can be quite scary at first but I think might help in your situation.
All it is, is holding the weight off the rack as If you're about to do a rep without actually moving it and hold it there for a few seconds.
Work up to 120% of your 1 rep like an isometric max, and just lift it off the rack. You'll need a spotter and/or the safety bars like a squat rack or Smith machine.
But make sure you can't drop it on yourself!
It'll help with getting your nervous system used to the heavy weights as well as improve and strengthen your supportive tissues, multi-joint involvement and muscle activation to improve strength and stabilization.
We probably all need training our ancillary and support muscles so probably good to train them for a few weeks (a few weeks).
Bench primary muscles worked:
Pectorals (chest)
Anterior deltoid (shoulders)
Triceps (arms)
Serratus anterior (periscapular muscles)
Secondary muscles worked:
Anterior core (abdominals and obliques)
Erector spinae and multifidus (lower back)
Hip flexors
Rotator cuff (shoulder joint supporting musculature)
You also have the muscles around each of the joints, which is basically means all the rest of the upper body.
If you're interested in purely bench, you could work on each one.
Personally, I'd try doing an (upto) 120% static hold on the bench which can be quite scary at first but I think might help in your situation.
All it is, is holding the weight off the rack as If you're about to do a rep without actually moving it and hold it there for a few seconds.
Work up to 120% of your 1 rep like an isometric max, and just lift it off the rack. You'll need a spotter and/or the safety bars like a squat rack or Smith machine.
But make sure you can't drop it on yourself!
It'll help with getting your nervous system used to the heavy weights as well as improve and strengthen your supportive tissues, multi-joint involvement and muscle activation to improve strength and stabilization.