CORE RPG RULES
Iconoclast -- RPG -- Combat Movement
As explained more fully under Tertiary Attributes, your speed rating (which is to say, the average of your five Physical Attributes) represents not only high-level things like how quickly you can run in Miles Per Hour, but also how far you can move during a combat round.
Since most combat is assumed to take place within the "combat range" of approximately 25 yards, movement outside of that range will move you into medium and long range. This is a good idea in the event that you feel death is imminent, since it will mean modifiers to the Targets of people who may be trying to kill you.
Your speed, as it stands, represents the number of yards or meters that you can move within one round (6 seconds), assuming you are moving at your typical "combat speed" of something a bit more urgent than a leisurely walk to the store to buy groceries. This also results in an automatic loss of 1 Vitality per round (which is the least of your worries within combat).
Just like dodge and deflect, movement within combat affects the beats that you can act and react in. For every 10 meters/yards of movement, you suffer a 1 beat loss; that is to say, if your speed is 20, and you choose to move 20 yards within a round of combat, you suffer a -2 beat penalty while you move, since you can't do what you normally could if you were just standing still and dying like a man.
This determination is ONLY made if you choose to move more than 10 yards or meters within a single beat (ie. more than 30 feet per second, or about 20 miles per hour, which is quite obviously impossible for most people). Since you can't physically move that far, that fast, within the realm of a typical combat scenario, the beat penalty represents the additional time it takes you to complete the movement. Thus, to move about 10 yards/meters at once, you take a 1 beat penalty (which represents running about 10 MPH) and to move about 20 yards/meters at once, you take a 2 beat penalty (which represents running about 14 MPH).