Hi Paul.  I have danced for almost ten years now and admittedly, ballet is a taxing advantage.  Can you walk, of course you can.  Do you run- for sport.  Or have you.  The necessary evil for the athletic minded is that ballet reinforces the idea that strength of the foot and all its magic minded bones need a structural enhancement prior to beating its pattern into the earth and ballet is just that suchness.  American ballet is a hodge podge of the French, Russian, and American schools.  A few book referrals...Ballet Basics by Sandra Noll Hammond the everydancermusthave!!!Technical Manual and Dictionary of Classical BalletGail Grant.

Expect to begin at the bar.  Take it from me, put one up at home.  Go to the hardware store and  get a pair of 8 inch corner brackets, a 6 foot wooden post bannister and a whole lot of 2 and a half inch metal screws.   buy a set of mirrors and teach yourself to stretch properly as you go along.  The barre is your friend and your number one asset.  The major need to knows are your porte de bras; french for carriage of the arm.  Your five major positionings of the foot.  Your ten most important barre exercises.  All of these ideas are explained and illustrated in Gail Grants book.  Pick it up, it's 5 bucks and a mentor in and of itself.    Good luck with your French.