unrealistic foot chase

The foot chase is entirely fake for two reasons:

1) Tibbs is carrying a revolver in a cross-draw holster tucked in his trousers, to the best that I can ascertain. When beginning the foot chase, he presumably tucks it in his holster and snaps it shut. Running as he does, you'd think the jacket would flap back to reveal it, right?? I couldnt' see it. And Tibbs crosses over barriers and jumps and lands here and there without a wince when the gun (albeit a snubby revolver) is squeezed into his midriff. Ever run with a gun in a holster?? I have, it aint what it looks like in Hollywood........

2) At the conclusion to the chase, Tibbs is not out of breath one bit; even an Olympic athlete would be catching his breath to some extent.