How can regular participation in physical activity improve an individual's overall health?

Physical activity can improve both one's physical and mental wellness

doing regular exercise will increase one's metabolism and immune system. Not only that , it usually help to relief stress and tension which will help one's mental health

Regular participation in physical activity has various benefits for an individual's overall health. It will improve various biomarkers usually designed to test for the likelihood of a person experiencing bad events in the future such as cardiac arrest, stroke, etc. 

They probably don't understand either 1. what the nightmare is about or 2. his anxiety and stress