Stretching is not just about trying to do the splits, it's about restoring the bodies ability to move. As we go about our daily life's we are constantly moving against gravity and as creatures of habit we tend to do the same things every day. Whether that means sitting at a desk all day, exercising with weights or running every day or standing on your feet all day. As a result of this repetitive motion or lack there of, the body will slowly adapts to what your doing. Some areas will get tighter from the overuse while others may get weaker. Over a period of time this imbalance slowly increases inflammation in the joints and surrounding tissue which disrupts the ability to move freely. A body (whether it's a joint or muscle tissue) under stress is slower to recover and repair from daily life activities then a body free of stress.
So this is where stretching comes in.
By incorporating a daily stretching routine your training the body to be better at recovering and adapting to these stresses. In a way your bring yourself back to center. The other thing about stretching daily is you begin to learn how your body feels from head to toe, you begin to have a better understanding of what's normal tightness and when something is out of balance and needs extra work by a professional such as a chiropractor, massage therapist or a flexibility therapist such as myself.