Pressure felt in back while doing seated dumbell press

[wordski]

I was doing some seated dumbbell presses to start off my shoulder routine last night.i admit this is my first time really focusing on my soulders I usually neglect towards the end of the week.Anyway,my first set was pretty light so I could get the feel of it.They felt good so I kicked it up a notch,IIRC,the second set was using 30lb. bells each,while doing the reps.,I felt some "pressure" in my back on the right side of my spine.Not alot of pressure but I did notice it.The next set was 40lb. bells,and once again the pressure was there.One thing I did notice was even though I was seated with a backsupport,I still had a slight arch in my back from just trying to support the heavy weight.Is that the culprit?BTW,my back feels fine but Im just trying to prevent any injurys. Like Jerome says "Injury free baby!"

[coffee-guy]

You need to tense your body throughout the entire exercise to maintain internal pressure on your spine as well - in other words you can NEVER relax your body during this exercise. Also, if you can possibly get into the habit - standing over sitting is almost always the better choice when it comes to exercises that can be done either way (shoulder presses, laterals, bent over laterals etc). When you are seated you are just compounding the pressure onto your spine.

[wordski]

okay,thanks