Although, you want to work on your back muscles, doing poorly may cause injury instead of actually training. Learn why I would recommend you to come to the gym to train by the hyperlink below.
Back is rounded
When you perform the seated row, your back should be the neutral curve. But oftentimes people forget when you start and when you end this movement, then your back is rounded. Placing the feet first, “back is neutral”, then pull the weight to be in a starting position.
Swinging
Unless you are doing seated rows for sport specific reasons, your feet, knees, hips, and spine should be fixed but only shoulders and elbows are moving. That’s because your target muscles are used by shoulder extension , elbow flexion and scapula retraction. You don’t need to swing your body at all.
Shrugging the Shoulders
As I mentioned, your scapula should be retracted as well as depressed (i.e. packing the shoulders). Shrugging the shoulders throughout the movement is not good for your shoulder health at all.
Scapula retraction and depression