Yoga decreases anxiety and depression. All movement helps with depression, and Yoga in particular helps with mood and other imbalances.
When you're calm and confident, you have deeper wells of energy and stamina when faced with our normal hectic daily lives.
One benefit of yoga is that muscles that have become flaccid and weak are stretched and worked repeatedly to shed excess flab and to spring back into life.
A benefit of Yoga is that the positions act upon various joints in the body, including ones that don't get worked very frequently. Not only do your joints loosen up but also they develop greater range of motion.
One of the far-reaching benefits of yoga is the uncanny sense of awareness that it develops in the practitioner; somatic and kinesthetic awareness. As you move your body through the various Yoga stances, a twinge or swelling in a particular part may alert you to impending illness.