I recently wrote an article for Next Avenue: Think Old Age Means Decline? Then It Probably Will.
Notice the older people around you who are living happily, who think of age merely as passage through time — those who expect to continue to enjoy good health, enough energy to do what pleases them, who figure life is meant to be lived fully, until the day their expiration date comes due. Use them as your benchmark of what life can be like for you as you travel through your 60s, 70s and beyond.
For the entire article, here's the link: http://www.nextavenue.org/think-old-age-means-decline-probably-will/.