Hi Welcome to HCM
I have gone thru your your query and am  glad to know  showing  interest in follwing  regular exercise regime for elderly woman .
 Regular Exercise is very essential  along with  healthy diet containing all essential nutrients  as fiber ,
vitamins , minerals , supplements full of antioxidents , in natural form --fruit ,green veges  , lemon , ginger ,garlic , 
aloe vera , turmeric powder  etc,.
With all you are doing is fine and can include Yogic exercises from  head to toe ,  like Pranayam  - deep breathing , Kapalbhatti , Bhujangassan  , Sarp assan  , Vajjarasan  all and more will strengthen your vital parts , give you resistance from  diseases  and assure healthy happy life ahead .
You can look for DVD  of  Baba Ram Dev,s 
yoga  . they are available all over the World  .
It is suggested to consult a specialist  for proper guidance  . 
Hope this helps solves your query .Take care .All the best .Get well soon
Don't hesitate to come back in case of any further query .