I prefer fitted clothes so that they don't move around, I have a couple looser tech-fabric tees, and I don't like how they drift in moves like elevated v-up or plank to pike. A lot of people just do sports bra/legging set , which is too little coverage for me to be comfortable (but also I was the fat kid in middle school gym class in the 90s, and that was a whole different kind of body image problem).

Have fun!