I always wear the same shoes that never trigger alarm : Clarks casual.

I have a metal bar in my right leg after a ski accident.
It triggered the alarm only once. At a minor Chinese airport. The guy tried desperately to find what was beeping his hand-held metal detector, didn't find out and gave up.
I didn't tell him I had a metal bar inside my body, as I knew that it was the best way to become suspicious and finish naked in front of four or five inspectors.