Elbows and body during sPL PE1

The main point of this exercise is to put stress on the shoulder blades, but I find it difficult for me to do so without slighlty bending my elbows and allowing some sag from my torso and stomach. Is this excusable or should I work on this immediately?

Lock the elbows. It takes a bit more focus but the whole movement should come from the scapula.

It can be pretty difficult keeping a straight body line, but it's something you should strive for.

 

If your elbows are bending, slow down the tempo.

I used to find my elbows bending, then I focused on really pushing my palms down and imagining trying to pull my elbows together. My bodyline has definitely stiffened up whilst I have been doing it as well, I try and stay hollow and lately I have been noticing it in my quads as I lock everything up.