ALS is my biggest fear--and I have many, believe me. I've had total body twitching off and on for many years. The latest episode, which ended about a week ago, the twitches would be all over, jumping from my calf, to bicep, to foot, etc. At night the arches in both feet would cramp really bad. This went on for weeks. This time I was sure it was ALS. Then I figured out that I had just started doing heavy lunges without wearing sneakers (no arch support), so that must have been the cause of the cramps. As far as twitching, it's just something that comes and goes for me. A friend's father had ALS years ago, and I remember he said his father had a hard time reaching for things in his back pocket. Other cases usually present with clumsiness and tripping. I wouldn't worry too much about random twitching without other symptoms.