LoopOut to loop animations is pretty simple concept. But in this case, I’m using 2x LoopOut expressions on 2 properties. The trick is that I’m overlapping values, to give an illusion of continuous pulse effect.
You can see this in the preview of expression on both properties – Dot reaches max size and in the same time, Stroke goes to 0. And then animation repeats itself, to sell illusion of constant pulse.
Simple, but very effective.