Answer:
I would think most people neglect physical activity because. They don't want to put in the effort of working out (which is hard work). If you look it up there are hundreds of so called fat killers that are suppose to burn fat without you working out, people are always searching to find the easiest way to exercise. Secondly, they like what they are eating. When you are trying to lose weight or gain muscle, you have to eat correctly, you can't be eating junk food (pizza, hot dogs, burgers, ice cream, soda, etc.). These two reasons are why I think most people don't want to do physical activities.