The purpose of this study was to test these hypotheses and determine the effects of long-term, vigorous exercise on the onset and progression of amyotrophic lateral sclerosis (ALS) in mice. Thirty-seven mice were divided into three groups: active, sedentary, and control. The results indicated that there were no significant differences in the course of disease between the groups and onset of disease in the active group was not significantly different from the other groups. The authors state that their results support that prolonged, vigorous exercise "does not promote the onset or progression of motor neuron degeneration in SOD-1-mediated ALS."