Many people wonder how a desk job can be so mentally tiring. The ego-depletion theory states that there is a limited amount of mental energy which we consume while sitting and working, just like a gas tank guzzles up all the gas till it’s empty.

This theory is being challenged, as we may be wrong on how our brains and bodies consume energy.

It turns out that the things that we aren’t motivated to do, and yet have to do (like going on a sales call, or making a report) will tire us out quickly, but the things that we love to do, or are doing on our own accord (like scrolling through Instagram) do not cause any psychological fatigue.