Just finished up the coronavirus home gym. Bought a cheap bar that I think is a little thicker than the power bars I’m used to so like 30mm vs 29mm diameter.
I’m feeling a bit beat in my elbows and shoulders which is very unusual for me. Could the change the different bar contribute?
My experience with thick bars is less wrist and elbow pain. But I’m also moving less weight with the thicker bars.
The bar is 1mm thicker than what you’re used to?
Powerlifters… 
Every mm counts
Yeah usually with 1 mm difference I’ve noticed a change but as the bar gets thicker, the difference increases. Like clee78 said, less elbows, wrist and shoulder stress. I usually use the thicker bar for my bench and press
In theory thicker bars are less pain.
In science it’s bullshit.
In practice I’ve come to believe the theory science be damned.
I think a cheap bar even though it is thicker might have more whip than you are used to. That can cause elbow pain. This is a bit of a stretch, but my elbows and shoulders feel better with a squat bar than power bar in the squat, and I think it is due to the whip.
I always feel better with thicker grips. As an aside, I’ve been doing chins almost exclusively with Fat Gripz and haven’t has the typical elbow flare ups associated with lots of chinning