Why is it necessary to have periods of relaxation and why too much of it is not good? (Besides the economical)?

humans thrive on moderation. too much stress, too much work... it all leads to over-working the brain, and results in serious fatigue. to relax is to rest the brain and rest the body so that it can perform at maximum capacity. the amount of relaxation needed for the body depends on the person. someone with an incredibly stressful job may need more than someone else, and some people work better with certain types of relaxation over another. the important thing is to find something that works for you. i'd try a variety of different relaxation techniques if you're looking for something to relax yourself. yoga seems to be popular with some people, while music, walking, watching television, reading a book, sitting on a porch, etc might be good for another.