Fatigue

Fatigue is one of the four essential needs. Fatigue is the measure of how tired the character is. Fatigue constantly drains but can be replenished by sleeping. As the character tires, Fatigue begins to affect the ability to move, aim weapons, and struggle. When completely depleted, fatigue will begin to lower the player's condition.

Gaining/Losing Fatigue

As long as the character is awake, fatigue will constantly be emptying. The rate of drop is directly dependent on activity level and encumbrance but may also be influenced by other factors like temperature and illness. Example: The fatigue bar can be emptied as quickly as in 2.6 game hours by sprinting as often as possible, while a long rope climb can easily consume half the player's fatigue in minutes. However, remaining inactive by passing time at a bedroll will see the same bar last almost 22 game hours.

• Properly balancing one's activity level somewhere between "always resting" and "always sprinting" should see most players make it through a 12 hour activity period before reaching exhaustion, provided that they're not exploring in an area full of climbing ropes.

Sleep

Sleep is the most common method of satisfying fatigue. It takes 12 full hours of sleep to fully replenish an empty fatigue bar. Or 1/12th of the bar will fill for each hour slept. The player will wake automatically when the bar has been completely refilled.

Coffee

Cups of coffee can be used to help ward off tiredness. When consumed, it fills 10% of the fatigue bar. It also confers the affliction 'Fatigue reduced' which slows the rate at which fatigue empties.

Emergency Stim

Emergency stim immediately boosts the fatigue bar to full and keeps it there until the effect wears off, whereupon fatigue immediately drops to 0.

GO! Energy Drink

Drinking a Go! Energy Drink will immediately refill the player's stamina and half the player's fatigue for a total time of 45 in-game minutes. After 30 minutes, the player will get a headache, and, at the end of the 45 minutes, the player's fatigue will drop by 50%.

Food

Eating certain foods can also affect the fatigue meter. Any type of stew will immediately increase the player's fatigue by 15%. Likewise, eating Rose Hip Pie and Peach Pie will fill 15% of the fatigue bar.

Affecting Condition

When the fatigue bar is empty, condition begins to drain. The rate of drain is fixed at 1% per hour (See: Needs). The slowness of this drain has lead some players to take advantage, accepting minor condition losses during strenuous activities in a practice known as Hibernation.

Other Effects

Sprinting

Sprinting contributes significantly to rate of fatigue. In turn, fatigue affects the replenishment of stamina which enables sprinting. When the character reaches Exhausted (empty fatigue bar), sprinting becomes impossible. It will remain disabled for as long as the fatigue bar remains empty.

Rope climbing

Rope climbing is much faster when the player is well-rested. Climbing up a rope is the most strenuous activity in-game, emptying both fatigue and stamina very quickly. When the player becomes exhausted, it is not possible to start a new climb, and climbing will become very slow. The rate of stamina decrease, however, remains constant, increasing the risk of slipping and falling.

Carry Weight

The amount of weight the character is carrying increases the rate of fatigue. Also, as the fatigue bar reaches below 50%, the 'recommended encumbrance' will begin to decrease. Encumbrance penalties apply as normal (i.e if your total carried weight is greater than your 'recommended encumbrance', too much more and you cannot sprint, etc). Once the 'Exhausted' fatigue state is reached, 'recommended encumbrance' will become half the normal value (or 15kg). This can be fixed with adequate rest.

Ranged Weapons

The ability to hold a weapon steady while aiming is affected by fatigue. This can be significant for using both the hunting rifle and the survival bow. Aim will waiver more when the fatigue bar is low (See:Hunting).

Struggles

When the character is fully rested, struggles seem to take less time and the struggle bar seems more easily filled. As exhaustion sets in, the opposite becomes apparent. Great difficulty is imparted and the struggle bar may become impossible to move. Being attacked by Animals during exhaustion is extremely hazardous. It's worth noting fatigue has no direct disadvantage in a Moose, or Bear mauling, due to the inability to fight while being mauled.

Starvation

If a player remains starving for a long enough time, the maximal amount of rest that they can acquire will start to gradually decrease. It is noticed by the yellow exclamation mark that appears beside the eye icon and by the red colour that starts filling up the inside of the fatigue bar. This issue is easily solved by consuming food, the red colour inside the fatigue bar will then gradually start to decrease, but that doesn't prevent the player from entirely filling up their fatigue bar with sleep right away.

Fatigue Bar

Fatigue bar progresses from Exhausted ↔ Drained ↔ Tired ↔ Winded ↔ Rested. Arrows in the bar indicate which direction it is filling with more arrows meaning faster progress. Fatigue is the inverse of the fatigue bar, meaning that when the bar is full, fatigue is at a minimum, and when it is depleted, fatigue is at a maximum.

Exhausted

• Constant Condition drain
• Cannot sprint
• Recommended encumbrance reduced to half normal (15kg/33 lbs)
• Significant difficulties aiming bow/rifle
• Severe penalties during struggles
• Rope climbing is slow and falls become extremely likely

Drained

• Noticeable difficulty aiming bow/rifle
• Significant penalties during struggles

Tired

• Recommended encumbrance begins to drop when the fatigue bar reaches below 50% in all difficulties
• Rope climbing at average rate of speed

Rested

• Sprinting seems enhanced (faster/less stamina drain)
• Bow seems steady during aiming
• Struggles seem easier (except against bears)
• Rope climbing is easy and fast

Hunger and Parasites affects fatigue

A player that remains starving for a long enough time will start to have their fatigue affected; the maximal amount of energy that the player will be able to acquire through sleep will start to decrease, which is represented by the red color that starts filling up the inside of the fatigue bar, as well as by the yellow exclamation mark that appears next to the eye icon, symbolizing the fatigue bar. This issue is easily solved by consuming food, the red color won't vanish immediately, but the player will be allowed to gain full energy from sleep right away.

Intestinal parasites also slowly drain the player's maximum available Fatigue bar to the same effect, but have a far harsher treating period.

Character quotes

• "Not sure why I feel so tired."
• "My energy is just...disappearing."
• "Just need to close my eyes..."
• "I'm gonna need to find a place to rest soon."
• "Something is sapping my energy."
• "If I don't rest soon I'm gonna faint."
• "I could go for a nap right about now."
• "(Yawns) I'd lay down right here if I thought I'd ever wake up again." (Male Survivor)
• "So tired I could lay down right here." (Female Survivor)
• "Think I need to lay down."
• "Gonna need to rest soon"
• (Tired exhausted sighing sounds)
• (Deep and heavy inhaling and exhaling)
• (Yawning sounds)

Trivia

The player character can stay awake well in excess of 24-36 hours in game without napping/sleeping and still function and audibly respond to needs semi-normally. It's been well documented that sleep deprivation causes a sharp loss in cognitive, rational, and problem solving skills in addition to other detrimental symptoms, such as; drowsiness, decreased focus/concentration, decreased awareness, degradation of short-term memory, and reduced coordination. Ironically, speed runners in Challenges deliberately avoid sleeping in order to lower their challenge record time.