Was 2013 the year of Pharrell Williams? With chart toppers such as Blurred Lines and Get Lucky, this writing and producing veteran has suddenly become a rising star.
1 Take the Exercise and Fitness Quiz!  AMS (acute mountain sickness): Acute mountain sickness (AMS) is the effect on the body of being in a high altitude environment. AMS is common at high altitudes, that is above 8,000 feet (2,440 meters). Three-quarters of people have mild symptoms of AMS over 10,000 feet (3,048 meters).
Stiff-person syndrome (SPS) is a rare neurological disorder with features of an autoimmune disease. SPS is characterized by fluctuating muscle rigidity in the trunk and limbs and a heightened sensitivity to stimuli such as noise, touch, and emotional distress, which can set off muscle spasms.