Many people divide the day into work time, me time, and sleep time, with work time generally allotted the most number of hours.
According to this symbolic timepiece, Ayurveda sections the day into 3 parts. The day starts at sunrise, with cool, heavy, earthy energy from 6am to 10am. The middle of the day, from 10am to 2pm sees the hot, sharp, and fiery “king of digestion” energy. And the light, dry, airy energy rules the afternoon, from 2pm until 6pm. The same cycles happen again at night.” — diagram from The Ayurveda practice
This knowledge explains why, when we wake and get out of bed before 6am it seems easier than it is after 8am, when the heavy earthy energy is prominent.
The reasons for this are clearly based on the energy of the time; energy changes throughout the day and if this interests you, can explore more about Ayurvedic principles here, and should the third party link break, search The Ayurvedic Clock.