Exercising, reading, getting a good amount of sleep, talking about your problems, socializing with a healthy group of people.
Aerobic system is predominantly used during medium to low intensity activity. The predominant energy system being used at rest is the aerobic system.
I think the answer would be, The Pericardium.
Lets say a insect is going to land on a man's eyeball his reflex would be to blink. Therefore preventing damage to the eyeball.
