Does Mom want to do something trendy? How about yoga & pilates?
Suzanne Deason's misnamed "Yoga for Weight Loss" is a terrific intro to yoga. There are stacks of great pilates intros, "A.M./P.M Pilates" for one.
I'm not suggesting that pilates & yoga can replace weight training & cardio in a fitness routine. But the flexiblity training, core work & often gentle strength training in yoga & pilates is very useful, especially as we age.
Debra