Stamina

Stamina, a core stat in DayZ Standalone, is a representation of your character's ability to perform prolonged physical effort. Whenever your character performs an action that requires a high degree of effort or exertion, they lose Stamina.

Survivors lose Stamina, either gradually or instantly, depending on the action they performed. Losing too much Stamina can result in fatigue or exhaustion, preventing your character from performing certain actions until they have had time to recover. While it is important to monitor and manage your character's Stamina, there is no penalty for having it drop to 0.

Recovery occurs on its own, with the recovery speed dependent on what the character is doing. Compared to the other core stats, Blood, Health and Shock, Stamina recovers incredibly quickly. At rest, a Survivor can go from no Stamina to completely recovered in about 20 seconds.

Overview
The most dynamic of the core stats, Stamina is the representation of your character's endurance; with its loss representing your character becoming more fatigued. In terms of immediate survival, Stamina is the least critical of the core stats. However, due to its ever changing nature, Stamina requires the most management.

Stamina is lost when performing actions that require a lot of physical effort, like sprinting, jumping or swinging an Axe and gained while resting or doing activities that require little physical extertion. The rate or amount of Stamina lost and gained is dependent on what actions are being performed. Stamina recovery always happens gradually, over time. Losing Stamina, however, can happen gradually or instantly. Actions like sprinting or quickly swimming will cause a gradual loss. Actions like jumping or attacking with a melee weapon will cause an instant loss.

The amount of Stamina a survivior has can change as well. All survivors begin with 100 Stamina. As they begin to pick up equipment and gear, the amount of weight they are carrying will start to affect how much Stamina they have. The more weight a survivor is carrying the less Stamina they will have available to them. Carrying too much weight will cause a survivor to become overloaded, preventing them from performing certain actions until they drop some of the weight they are carrying.

Character Load Weight
In DayZ Standalone, Stamina is affected by one thing, how much weight a character is carrying. All items, from apples to weapons, have weight. As a survivor begins picking up equipment, food, clothing, etc., they begin to increase their load weight (i.e. the weight of the items they are carrying). All survivors can carry about 6 kg of load weight with no issue. After that, they will begin losing maximum Stamina; losing about 1.75 Stamina for every 1 kg of weight carried. It is important to note that a character's load weight does not affect sprint speed or Stamina recovery, only maximum Stamina.

If a character is carrying enough equipment, they will begin to become overburdened; losing so much maximum Stamina that they are unable to perform some actions. This Stamina penalty does have a cap, with no character able to lose more that 95 maximum Stamina. Still, having a total of 5 Stamina (with the maximum penalty) doesn't leave many options available to the survivor.

If, at any point, a character drop some or all of the load weight they are carrying, their maximum Stamina cap will instantly increase (the character's Stamina will need to regenerate back to the new maximum value).

Recovery
As long as a character is not performing an action that is physically exhausting, they are regenerating Stamina. The speed of their regeneration is dependent on what the character is doing at that moment. A player can use an Epinephrine Auto-Injector to completely restore their stamina, and run with maximum stamina for a prolonged time. This was added in the 1.04 update.