By Mayo Clinic Staff. An X-ray is a quick, painless test that produces images of the structures inside your body â particularly your bones. X-ray beams pass through your body, and they are absorbed in different amounts depending on the density of the material they pass through.
Physical Causes. The most obvious reason for being tired and sleepy is lack of sleep. According to MayoClinic.com, the average adult needs between seven and eight hours of sleep every day. If you're sleeping less than that, adjusting your sleeping schedule might provide some relief.
1 Anxiety causes profound muscle tension all throughout the day, and often this causes a similar drained feeling that makes your body tired.  Mental Tiredness Some of that tiredness is entirely mental, simply because your brain - like a muscle - can also run out of strength. Anxiety can cause a host of rapid, stressful thoughts. When it does, your brain is incredibly active.