Thump Foot to Stop Nosebleed

Q. I learned a procedure from a wrestling coach to stop nosebleeds. Determine which nostril is bleeding, remove the shoe from the opposite foot and with the heel of your hand give two good thumps to the heel of that bare foot.
I have used this tactic many times, in the gym, on field trips, at Little League and even on my wife sitting in the car. You should have seen the look on passers-by! My question is, why does this work?
A. We wish we could tell you. It makes about as much sense to us as dropping keys down the back of the neck to stop a nosebleed. Many readers have shared success stories with that technique. Even though we can’t explain either approach, it will be obvious within seconds whether it has worked. Drugstore alternatives include Nosebleed QR, NasalCEASE and Seal-On.