The answer can be both increase in self-esteem and increase in aggression. All of the research generally points to increase of self esteem because during puberty self awareness is very prominant which increases self esteem. I would be safe and go with self esteem. I hope this helps.
I hope so! Having friends and being able to socialize with them is a very important part of mental health.
The independent variable is the exercise program (high vs low)
The dependent variable is what they are measuring so it would be the subjects stamina. The dependent variable is measured by how long they can walk comfortably on a treadmill (at the end of the program).
