The HUD, which shows West's Stamina.
Stamina is a resource that is consumed by performing physical activities. It can be seen in the lower-left corner; it is the white bar that wraps around the right side of the sphere, and the sphere can be hovered over with a mouse to see a numerical value. Stamina slowly regenerates over time, and regenerates more quickly while sitting or sleeping. Actions that consume stamina also accelerate fatigue buildup, as well as thirst and hunger to a lesser extent; this acceleration occurs even if stamina is not actually consumed.
Stamina is used when performing melee attacks, including unarmed attacks, instead of consuming power from power packs like guns do. It is also used for dodging. Both actions consume a small chunk of stamina, and cannot be performed if there is not enough stamina available. Finally, stamina is slowly consumed while sprinting. If all stamina is depleted, it will take a few seconds to begin regenerating, and will slow the player down below walking speed for a short time.
- Sprinting drains West's stamina and depletes oxygen. It also alerts enemies in the area, including enemies on the other side of doors. West can't sprint if he runs out of stamina or if he has a fractured leg. Sprinting will cause increase in hunger and thirst needs. -In-game Help Text
After sleeping, a "well-rested" status is obtained for a period of time (proportional to how much time was spent sleeping); this status decreases stamina consumption while it is active. Windroid can be consumed to reduce all stamina consumption to zero for a short period of time, based on the tier of windroid that is used.
Maximum stamina can be affected by a few factors. Under normal circumstances, maximum stamina is 100. If Fatigue reaches 75 or Thirst reaches 90, max stamina will drop to 33, and eventually to 25 if the fatigue is not addressed. Max stamina will slowly increase back up to 100 while neither condition is met.