This exercise helps improve core stability. It’s important to try to keep the hips equally aligned, the back in line with the leg and arm and not wobble! Head and neck should also be aligned with the back not looking up or down. Mine I’ve noticed is slightly too raised.
Now for the abs.
Struggling a bit and the dog still not too impressed…
Engaging the core, using the lower abs, rising and lowering with a straight back with as much control as possible. Also using glutes, hip flexors and quads. (I think)