Lou Gehrig was a famous baseball player who played for the New York Yankees. His skill earned himself the nickname "The Iron Horse". However, near the end of his career people started to notice he was playing a lot worse for an unexplained reason. He suffered from amyotrophic lateral sclerosis (now commonly known as Lou Gehrig's disease) which originates in the brain that doesn't really affect mental ability but eventually renders most of the muscles in the body useless. While some people have survived the illness, Lou Gehrig did not as he died in 1941.