Remember for optimal health and fitness always perform stretches, as we mature we become more and more less flexible, this is why it is good to stretch daily.
Stretching exercises for health and fitness are very easy to perform. The normal ones for legs such as touching the toes and hamstring stretches are your most common stretches. For arms you can do anything from arm twists. For your upper body a great stretching exercise is to perform twists side to side with a weightless barbell behind your neck.
If you are are pursuing martial arts or want excellent flexibility in the legs then you can perform the splits each day, take it very easy when doing this if you are new to exercise, pushing your self could result in severe pain, and in some cases, even damage.