From feudalife

The player requires energy to use Tools, Fight or to work in your farm, in general, the energy is the base of all your work.

Energy lost

Every time you do an action (like using a Tool or attack with your Weapons) your energy will decrease a bit, this can happen until the energy bar reach 0 (out of energy).

When you lose all your energy, the movement and the actions of the player will be decreased a lot, and you will need to recover some energy to continue working on your farm.

Energy recover

To recover the energy you will need to sleep in the Pallet, Tent or Bed House, also, you can drink the Energy Potion to restore your energy a little bit every second.