It's quite difficult to get right everytime you bench. You basically you need to push hard into the ground with your heels just before you push the bar off your chest. This will generate leg drive which will help you to get more out of your bench.
I do something similar. I remember watching a video where Dan Green is saying something like this, trying to extend your legs. From watching heavy benches, it seems like the arch collapses slightly when the weight comes down, then rises up higher as they begin the press because of the leg extension drive. I believe the amount of this you see in, say, Dan Green's bench is illegal in stricter feds, but I don't see how the mechanics of how your leg drive works would change if you eliminate the "sinking in" on the pause. Pressing the legs down and out seems to mitigate the ass lifting off the bench as well.
Last edited by Levon_Xidyn; 08-08-2014 at 04:50 AM.
I think JC explained pretty good. You use your legs to push your body horizontally towards the bar. This helps maintain your arch during the bench.
Foot position may affect things, this has been a helpful set of cues for me:
I think it's from Jack ReapeShoulder blades together, glutes flexed, feet pulled back but no so far that you can't get your heels on the floor, and when you flex the hamstrings you are actually pushing up towards your head rather than up towards the ceiling.
Check out this link: http://www.t-nation.com/workouts/6-w...nch-press-cure
There's an instructional video in there as well. Pretty good stuff if you want to spend a few minutes beefing up on bench press technique.
I find it helps to push your legs into the ground before you even remove the bar from the pins. After your upper back, low back and abs are tight push your legs into the ground too then lift the bar off the pins. If you keep the legs tight on the way down, you should get strong leg drive on the way up.