I've carried a Glock 20 Gen 4 quite a bit in a Runner's Kit Bag, both for running and backpacking. Also some cycling.
For running I carry the G20, a spare mag, a medium folding knife, keys, iPhone, small flashight, first aid dressing, bandana and sometimes my wallet or id.
For backpacking I carry the G20 and mag and a slimmed down version of equipage level 1:
The gun does not print. Someone familiar with a HPG kit bag would probably suspect you are carrying a handgun, but a "casual observer" would not say "I see the outline of a gun in that bag."