Every item in the game has a weight. When the player puts items in their backpack or equips them their encumbrance increases. Newly respawned soldiers are 14% encumbered, due to their hammer, pistol and two pistol clips. Your encumbrance also increases when mud 
accumulates on your soldier from moving on muddy terrain during Rain Storm.
Encumbrance directly affects the player's rate of decrease in Stamina when walking or running, as well as their movement speed. For vehicles, it only affects the speed in the three encumbrance stages.
Encumbrance levels[ | ]
Encumbrance is displayed in game as a percentage of a set maximum encumbrance. The number can be seen in the inventory UI screen.
| HUD Icon | name | Encumbrance | Effects |
|---|---|---|---|
| None | Light | 0% - 65% | The player or vehicle can move at regular speed. |
|
Heavy | 66% - 99% | The player will use more stamina when sprinting. Vehicles directly reduce speed. |
|
Overweight | 100% and more | The player will spend stamina even when walking. Vehicles reduce even more speed. |
Players[ | ]
For players, the movement speeds is directly related to the percentage of encumbrance. Being 0% gives a significant boost compared to 40%, but even the difference between 15 and 20% is noticeable during sprint. Players 0% encumbered sprint at a speed of 6.5m/s.
When encumbrance reaches 100%, walking itself will start consuming stamina. Reaching red stamina will cause your soldier to fall over. As encumbrance rises over 100%, the player will use more and more stamina for walking and running.
Vehicles[ | ]
As of Update 0.26 some vehicles are subject to some level of encumbrance system as well. This was implemented in order to increase speed for empty logistics vehicles doing return trips.
The encumbrance values of items in a vehicle are different than from a players inventory. For a Transport Truck, the ratio appears to be 1:0.18. The encumbrance of players in the vehicle does not count towards the encumbrance of the vehicle, thus storing items in your backpack could potentially lead to faster travel speeds in vehicles. The fuel in the fueltank also does not count towards the encumbrance of the vehicle.
The affect of travel speed of vehicles works different than from players. It is not directly tied to the encumbrance, but works with a constant speed within a encumbrance range (light, heavy, overweight), with each range having a different speed. With high encumbrance (100+%), the truck moves at 75% speed compared to 0% encumbrance. Going over 100% encumbrance does not affect the vehicle's speed further.
Data on encumbrance values in the Transport Truck:
- 15 Crates encumbered for 150% (while on a person, that amount would weigh 825%).
- 500 Basic Materials or 300 Pistol clips in a truck weigh 100% (on a person, they both weigh 545% each)
- 50 Rifle clips weigh 16% (on a person, it would be 90%)
List of vehicles with speed affected by encumbrance: