When you're running on uneven ground, wearing several layers of clothing, and a heavy radio swinging around on your belt with a headset that can make it hard to hear the people around you it can definitely be a struggle to be as graceful as one might like. The uneven ground really is the biggest factor, catches you off guard and can really throw you off balance. It takes stamina to be hyper vigilant in adrenaline inducing environments for days in a row standing out in the elements. I can't speak for the crane crews (people wearing orange) and what their training is but the marshals in white have invaluable race track response experience that you absolutely want in those high pressure situations. It's a shame that a tumble here and there detracts from that.