For decades, many people stretched before a workout but according to a new exercise guideline issued by the American College of Sports Medicine specifically advised against static stretching before workouts or competitions.
To stretch a muscle, it should be put in a position that produces a slight pull on the muscle but not to the point of pain. With a static stretch, the position in which a slight stretch is felt should be held 15-30 seconds, and each stretch should be repeated 3-5 times on each side of the body. The primary note regarding stretch position is that it should not cause pain or take the joint past the normal range.
If you have lost some joint motion or feel stiff, range of motion or stretching activities should be done daily. The muscles that are most often tight are the hamstrings, hip flexors, calves and chest muscles.