After reading this www.mamamia.com.au/jamie-lee-curtis-body-image/?fbclid=IwAR1RS1njwbsfb4gLx3mf3pf1kptnEQ4M9ylPnBmJleMqsYeMFfcKX1TO5SE
and seeing some things on TikTok it seems like people regularly clench their tummy muscles or suck in their tummy. I have never even considered doing this, a midwife told me after I had my first son I should pull my tummy in, but I thought she was just being odd (she then milked me so it was an odd exchange).
So AIBU to ask if you suck in?
YABU - Yes, I clench / suck in / however you want to put it
YANBU - No, I don't do this