The Running skill primarily affects the
speed at which you travel, which is why it is Strength-based.
The amount of time you can run is based primarily on your Body.
QUOTE (Shadowrun 4 Anniversary p.164)
Fatigue Damage
No one can run forever. After a period of sprinting, even the most conditioned athlete begins
to slow down. These fatigue rules simulate this phenomenon.
A character can sprint for a number of turns equal to his Body plus the hits on a
Running (Long Distance) + Strength Test before he or she begins to lose steam. If the character
continues to run beyond this base period, he or she begins taking 1 box of Stun damage
each Combat Turn from fatigue; this damage cannot be resisted.
If a character is merely jogging along at his base running rate instead of sprinting, the
gamemaster should increase the base period to (Body + hits) x 2 minutes, and only apply 1
box of fatigue Stun damage each time that period passes (rather than each Combat Turn)
The maximum amount of fatigue that can be taken is 6 boxes of Stun. After that point,
the character must make a Body + Willpower (2) Test each Combat Turn (sprinting) or
Body + hits minutes (jogging). If the character fails, he collapses from exhaustion and is
simply unable to continue any sort of strenuous activity until he rests.