People are 'old' in their 50's and 60's?! I call BS on that, as would most people that age. I've done more in my 50's that in my youth - started working out, joined the gym, finished a full marathon (walking and jogging but still), do more hiking and walking, etc. And sex. Much much much better now.
Just watched a video of a man over 100 years old who did a full marathon. He beat my time from when I did mine at 52.
Ditto caramix - we need to break the stereotypes of age. Life isn't all about the young. We don't turn invisible as we age. We don't lose interest in fun and physical things. And we need to stop acting like grey hair, wrinkles, and saggy bits are the end of the world.