The way your feet strike the ground will be different from the way mine and everyone else will. Having them strike wrong for your body can eventually cause shin splints and other injuries, but so will running too much, on harder or softer surfaces than you are used to or bad/old shoes.
Also, just to prove that I am not talking out of my ass about the running cadence of 180bpm, or 180 steps per minute:
from FM 3-21.5 Drill and Ceremonies
ch 4-5. para e.
All marching movements are executed in the cadence of Quick Time (120 steps per minute), except the 30-inch step, which may be executed in the cadence of 180 steps per minute on the command Double Time, MARCH.
ch 4-14. THE 30-INCH STEP, DOUBLE TIME
To Double-Time using the 30-inch step, use the following procedures:
a. To march in the cadence of 180 steps per minute with a 30-inch step, the command is Double Time, MARCH. It may be commanded while at the Halt or while marching at Quick Time with a 30-inch step.
b. When at the Halt and the preparatory command Double Time is given, shift the weight of the body to the right foot without noticeable movement. On the command of execution MARCH, raise the forearms to a horizontal position, with the fingers and thumbs closed, knuckles out, and simultaneously step off with the left foot. Continue to march with 30-inch steps at the cadence of Double Time. The arms swing naturally to the front and rear with the forearms kept horizontal. (When armed, soldiers will come to Port Arms on receiving the preparatory command of Double Time.) Guides, when at Sling Arms, will Double-Time with their weapons at Sling Arms upon receiving the directive.
This is from the July 2003 publication of FM 3-21.5
But this is totally something only crazed out iron men on bad crank could do. I still maintain that it is a stupid to say that 180spm is the perfect or ideal cadence or pace to run. I still maintain that running at any speed is fine, especially if you are just starting out and/or only do it to get into or stay in shape. You are much more likely to stick with a workout routine that pleases you than one that you feel forced to.