I wish I knew the secret. I suspect a lot is heredity.
Is this unreal or what? Recently, my mom ran into a family friend at a bridal shower. The friend is 93 years old. She told mom that she drove herself there and that she also drives herself to church on Sundays and Bible Study luncheon on Wednesdays. ( She has always been very conservative, like my parents.) She then leaned in and whispered to my mom that she also goes to the Elk Lodge dance every Saturday night! My mom gasped and she said, not to worry. That she had discussed it with the reverend and he said there was no problem with her dancing. lol
Note: There doesn't seem to be an problem with her driving. She also runs her own household, gets her own groceries and drives herself to the doctor. Go figure.