Quiltah Mama

They sell wobble cushions on Amazon, place it in a chair you already have instead of buying an entire wobble stool. I bought one and use it from time to time(I usually stand to sew) If it's making my core stronger, I wouldn't know it. But to me anything like that is worth a try.

maminstl

I use a stool with a curved bottom, creating some wobble. I love it - it's easy to turn and bend, easy to move from one machine to another and takes up very little space in my sewing room.

cheryl222

Do you mean like a dentist saddle stool ? https://smile.amazon.com/s?k=dentist...s_ts-oa-p_1_15

maminstl

not a saddle, just a stool with a gently curved base. I've had it a long time, so can't find an exact replacement on amazon