initially I worried that my stoma was vulnerable to damage, I lead a very rough and tumble life including often wearing a tree surgery climbing harness that crosses my stoma area with hard buckles and straps plus lots of heavy lifting of rough objects that rub up against my abdomen I spent money on a couple of stoma guards but no longer use them. Now I just wear a fairly sturdy elasticated stoma belt by Basko. It looks like a typical back support belt but has a hole to allow your bag to sit on the outside of it. However I just wear it right over my bag and find it gives plenty of protection. Also it helps hold everything tightly in place and keeps a nice flat profile so you can wear tight fitting clothes. I find that if anyone notices it they assume it's to support my back...which it also does, and is good for preventing hernias. You might think having a tight belt across your stoma would prevent it working properly but that's not so:)
a stoma looks so fragile, but I've found it not to be so.
hope this helps