Noise of course is a concern, however, Never, but NEVER run your shadow anywhere near a mounted horse. It is no matter whether it is bomb proof or not, the horse I mean.
I have seen horses buck and kick right over on their side from flat gallop when accosted by the 'shadow'.
That is not unless you can fight a bit, or your blood is up with a bloody belligerant stockman who is just NOT looking for directions.