Many older would-be dance students worry that they are too old to get anything out of taking ballet.
A quick survey of articles on the internet show that articles read by adult beginners in ballet outnumber those read by the (somewhat) more self-accepting younger ballerinas and men in ballet.
There seems to be a degree of self-consciousness in most adult ballet students that I hear from. However, the self-doubt is needless because it really does not matter, except to each individual, what the goals of studying classical dance are. Each to his own.
Some adult ballet beginners will attempt to train long and hard enough to dance in pointe shoes, yet many will not have that aim in mind.
Many want an exercise program that also lends to developing grace and elegance. As exercise, ballet provides high intensity workouts for the lower body, while also challenging the upper body muscles, in a lighter manner.
Properly taught and practiced, classical dance increases both muscles strength and stamina. Reflexes are improved, and if kept up through the senior years, ballet will help increase bone density, balance and muscle strength.
A strong heart and strong lungs' response in an emergency moment relies on muscle strength. The heart and lungs do not actually strengthen by prolonged low intensity exercise (such as walking and running) as previously thought. This is because the stronger the muscles are, the less the heart and lungs NEED to respond to a sudden burst of movement or intense muscle contractions.
I hope that adults who want to do ballet just go ahead. Whatever the flexibility and the resulting ballet positions, whatever the muscle type and the resulting ballet technique, the benefits are enormous and these adult exercisers are way ahead of the aging/degeneration progression.
Define for yourself what you want to get out of ballet classes, enjoy every minute of it, and throw away any needless self-doubts.
To support your ballet training, take advantage of the remarkable ballet education that is available.