The main objective of yoga is to help the practitioner cultivate an awareness of self and our connectedness to all things. It is about creating balance and calmness to live in peace, good health and harmony.
Flexibility is required for survival. Flexibility makes even trees stronger. Imagine what it can do to your body and soul. Even a gold medalist has to bend to receive his medal. You are as young, as your spine is supple, flexible and strong. All the back aches, postural problems arise from here. So work on your spine.