Friends often are made during sports activities. Exercise can give people the opportunity to mix with others. Sometimes people feel sorry for themselves. When they do this, they become stressed and produce adrenaline that can raise the blood sugar level. Other people like to watch TV and eat snacks that raise the blood sugar level.
Exercise is a good way to improve a bad mood and to change a bad habit.
In this way, exercise serves a double purpose. For thousands of years, people had to hunt for food and were very active. In the last 100 years, modern machines have made it possible for people to live with almost no exercise. This lack of activity has led to new health problems such as obesity and heart trouble. Exercise helps burn excess calories and prevents obesity.