List of United States Presidents by military rank. The United States Constitution names the President of the United States the Commander-in-Chief of the U.S. armed forces. Many Presidents, however, also served in the military before taking office; all but 12 of 43 served. 1  1 Table of United States Presidents by military rank.  1.1 General of the Armies.
It is called circadian rhythms. Humans tend to sleep when it is dark out. I, on the other hand must work all night and sleep in the day. so my natural rhythms are screwed up. Being bored makes us sleepy, reading and watching TV makes me sleepy also physical tiredness.
People who donât get enough sleep each night are more likely to get sick. Your immune system releases cytokines while you sleep. Cytokines are protein-messengers that fight inflammation and disease. Your body needs more of these proteins when youâre sick or stressed.