How does the brain physically get tired? When engaging in physical work-outs, people often research how regular muscles store energy, how to eat and exercise cleverly so that the exercises actually make them stronger and more healthy instead of making them constantly tired or even sick.

Where can I find similar explanations, but for brain, that would explain and describe how brain, as an organ, gets exhausted and what is the proper/recommended discipline for using brain as an organ the most effectively? (e.g. how should study sessions get scheduled, what should be included into the diet, what activities should be possibly avoided,etc)
The first rule of Neuroscience Club is to check your Kandel.

The second rule of Neuroscience Club is to check your Kandel.

Joking aside, the gold standard of neuroscience is Kandel et al.'s Principles of Neural Science, currently in its fifth edition. It's an extremely (and in the cognitive sciences, I would say uniquely) comprehensive and authoritative work, and you can certainly use it to find an explanation for your questions about how the brain stores and uses energy, or virtually anything else. It's that rare kind of book which successfully distills a massive subject down to something as simple as possible, and no simpler than that.


  Kandel, E. R., Schwartz, J. H., &amp; Jessell, T. M., Siegelbaum, S. A., Hudspeth, A. J. (Eds.). (2013). Principles of neural science (Vol. 5). New York: McGraw-Hill.


It does not really make sense to talk about "how to use the brain as an organ most effectively." The brain is only metaphorically similar to muscles, and only in certain respects. One of the relevant differences is that neurons do many things and often exhibit nonlinear behavior, whereas muscles more or less only stretch and contract. This currently makes it very difficult to scientifically define what optimizing brain function means, exactly, compared to defining what optimizing muscle function means. 

I will not deconstruct the question further since it is primarily a reference request, and this will all be more than clear from Principles of Neural Science.