Amyotrophic Lateral Sclerosis (ALS), more commonly known as Lou Gehrig’s disease, is a progressive neurodegenerative disease that destroys motor neurons, which are among the largest of all nerve cells in the brain and spinal cord. Motor neurons are responsible for sending messages to muscles throughout the body.
When the motor neurons can no longer send impulses to the muscles due to ALS, the muscles begin to waste away (atrophy), causing increased muscle weakness. Motor neuron (or nerve cell) death makes it impossible for the brain to control muscles or signal them to move. Eventually, most muscles are affected, including those of the legs and feet, arms and hands, and those that control swallowing and breathing.