In 2008 Iyengar told Yoga Journal:

"Even now, the maximum my body can do, I do. I am 90, and still I practice. I stay in Sirsasana (Headstand) for half an hour, even without shaking. I’m improving still, progressing still. That is why I am still practicing with such energy. The mortal body has its limitations. Therefore, I will still practice ’til the last breath of my life so that I do not become a servant of the mind, but rather the master of the mind. Old age makes a strong man say goodbye. I am breaking the fear complex and living with confidence."  See beautiful montage here.