What is the fastest running speed for a character and how can it be achieved?
Movement Speed in PlayerUnknown's Battlegrounds is determined by what weapon you are currently holding, as well as your current stance, plus any level 3 or 4 boosts from consumables (Energy Drinks, Pills, Adrenaline).
To break it down fastest to slowest:
Sprinting Player (holstered weapon) with Tier 4 boost = 6.7 m/s (+6.2% speed)
Sprinting Player (holstered weapon) with Tier 3 boost = 6.4 m/s (+2.5% speed)
Base Sprinting Player (holstered weapon) speed = 6.3 m/s
So, at your speediest it will take around 15 seconds to cross one white square (100m) of flat terrain.
So put your gun away and start chugging those pills and energy drinks if you gotta go fast.
(source, all speeds rounded to 2 significant digits)