Friday is the hardest day of the week. Irina Blinnikova, Senior Researcher of the Laboratory of Labor Psychology, Faculty of Psychology, Moscow State University, spoke about this in an interview with Radio Sputnik.

Blinnikova stressed that traditionally the hardest day is Monday, because you need to start working after rest. However, from a scientific point of view, Friday is no easier.
“Friday and the end of Thursday are still quite a difficult time. The accumulated fatigue makes itself felt,” the specialist noted.
She added that earlier unfinished work is accumulating by Friday.
"They (postponing things for later) waste at the same time (finishing tasks) an excess amount of resources and are in a state of heightened emotional and operational tension. You have to pay for this. You have to pay with your health, both physical and mental," Blinnikova warned.
She advised planning the time in advance and distributing the load evenly.