Points) This physical response causes adrenaline to be released in the body during times of
stress.
Decreased heart rate
Forgetfulness
Deep breathing
The Fight-or-Flight Response

The person who utilize the progression principle will keep adding the difficulty of the exercise that he's doing, while the person who does not, will only stay stagnant.  the person that utilize progression principle, will get a stronger endurance because now his body is conditioned to do harsher routines.{the answer was already on verified)