With this exercise like many, you must find what works for you. There are various grips, hand positions and ranges of motion that can be used to perform this movement. The main thing to find is a comfortable distance between each hand. Basically, what I find is anything inside of 12-14 inches will be effective. Despite what most people think, the position the arms are in when lowering the bar, does not make much of a difference. ARms in or arms out, the muscle is still being trained. Basically, try the many variations of this movement, and see what works for you. Best of luck.