It's never too late to prove at least to some degree man's agelessness. Agelessness, or eternality, is an attribute of God, divine Life and Love. Eternality is expressed throughout God's spiritual creation. It's reflected by man—the spiritual, perfect, immortal likeness of God. Therefore it's inherent in each one of us.
A woman I knew proved this to some extent. She was an active Christian Science practitioner for over fifty years. She was vigorous, perceptive, and animated by divine Love even as she approached her centennial anniversary.
How did my friend do it? She said she started praying about maintaining her freedom when she began her practice of Christian Science. She desired to reflect a Christly countenance. She worked to overcome each limitation associated with age as it came to her thought. Every morning she joyously prayed. She studied with gratitude the weekly Bible Lesson found in the Christian Science Quarterly. Then she strove to live with grace the precepts and truths contained in these Lessons as she went about her daily business.