When I go camping up here in some isolated camp spots in Alaska, I practice running right and left about 3-5 yards and shooting
at a stationery target (our range rules will NOT let folks do that around here). I figure in real life, you're not going to be standing still
while someone tries to make horizontal channels in your body. In all reality, if you're not behind cover, you're going to be trying to get to cover and so is the perp. I've shot a lot of rounds at stationary targets, standing and thought I was a good shot til I started running and shooting. Out of 5-6 shots, most I normally can get is 2 or 3 in or near a vital running as fast as I can, sometimes 1.
I saw a movie where a cop and Lenny Magill did this with paint bullets and Lenny and the cop were hard pressed to hit anything. Lenny did manage a couple of lethal hits on one try and the cop did 1 on Lenny once but overall, it's pretty tough to do. Anytime you can shoot at something moving or you moving is good practice IMHO. I always opt for a moving target if I could get it or a target that turns within a second or 2.