One thing most guys miss with a barbell row is to really set their base with their glutes and hams.
That’s the first thing I do before I lift the bar off the floor to give me stability. I make sure that there’s a lot of tension in my glutes and hams. The stronger that base is, the more stable you’re going to feel in the movement.
The other thing is I don’t do bitch reps. That’s what me and my training partners call those reps where you’re humping the bar. Where you raise up real high then kinda slam your body down towards the bar as it comes up. Bitch reps.
I focus on driving my elbows back with my weight at mid-foot. But here’s the thing - the barbell row is really an integrated movement. It’s not a “one area of the back to bias” kind of movement. It’s hitting everything.
I don’t overly arch my back. Just enough to not be in lumbar flexion. I think arching super hard with the weight in that position is probably a great way to end up with some back pain.
Mainly start light and make sure you’re adhering to all of the above and add the loading slowly.