Notice, along with keeping my arms perpendicular to the floor, I’m also ensuring that my upper arm path is conducive to doing so. The upper arms shouldn’t be flayed out to the sides, but in a slightly downward angle (somewhere between 25° and 35° from the ribcage for most).

Also, I don’t recommend necessarily locking out the elbows at the top (as you see me do in this vid lol - I was a little bit tired from all the lifts we filmed tbh 😬🤷🏻‍♂️), but end them with a soft(ish) bend instead in order to keep the tension on the muscle as much as possible throughout the entire set.