As a combat round is inconveniently long and vague where sprinting distances are concerned (in an Olympic race, reaction time, block clearance and achieving a speed of maximum acceleration all occur in a 4-second interval), the actual distance covered by a sprinter is broken down by action points expended rather than in terms of rounds.
Further, the highest speed possible by a character will be limited by any baggage or items the character may carry. In game terms (rather than reality, as I am lacking useful tables that can be applied to role-playing encumbrance), this will translate as a 40% reduction in potential distance covered per action point lost due to encumbrance the character carries. Since this will quickly reduce 'sprinting' speed to below normal speed, it may be presumed that when the character is able to move at a faster rate through combat running, it and the character's 'sprinting' speed should be seen as equal. The rule treats the matter this way to suspend any idea that sprinting ability is a form of combat superiority.
Additionally, sprinting is an exercise of focus and dedication of effort. Characters cannot dodge while sprinting, cannot attack, cannot shout encouragements to others, cannot recognize details from the world around them and so on. In sprinting, the character focuses ALL their energy on a single target and runs at that target in a straight line as fast as they can. If the character is not focusing in this way, the character is running in the combat sense, not in the sprinting sense.
Characters who are sprinting can propel their bodies against enemies with the intention of causing a collision - but this is not an attack. The enemy is entitled to a dexterity check to avoid this collision (unless the enemy is facing away, blind or otherwise unable to act).
To have a working system that would mesh with other aspects of movement and my combat system, I have had to sacrifice realism for play-ability. As such, do not attempt to compare the sprinting table as shown with comparable figures from modern events (I have reduced modern times by 25% in order to approximate issues such as the surface run over, a lesser grade of health and a practicality of play). All that matters is that the character has an option to bear down and run really fast without ridiculously overwhelming normal character movement (which it does anyway):
Once a sprinter has run full out at this rate for a little more than 3 full rounds (16 action points), the character will be exhausted but will be able to walk at normal movement rate. A character can move slower than the hexes noted above - but for ease of calculation demand that 'slower' movement be given a maximum of 7 hexes per AP, with the total number of AP that can be expended at this speed being limited to the character's constitution multiplied by 3. Thus a character with a 18 constitution could 'sprint' at 7 hexes, but would have to stop once reaching 126 total hexes.
Characters must wait 40 rounds before they can sprint again. They must wait 20 rounds before they are able to move at triple-speed and 10 rounds before attempting a ordinary running. Characters may only sprint up to 20 times per day.
Please note that I am aware the above does not allow characters to sprint a quarter mile distance before giving out and growing tired. I point to the note above regarding probable health for a person in the 17th century. Also, I've decided to include distances of a quarter mile or more elsewhere (see Endurance Running [placeholder].
See Running (ability)