My mother is in early 60's has been working out in some form or fashion (typically free weights or yoga) for 35 years now. She's in good shape for age (she can do three pull-ups with good form). But she recently had to have hip replacement, and she's lost some of her strength because she wasn't able to exercise as much until after the hip replacement surgery. Given the holistic scope of F1, I would really like her to start doing or F1 or at the very least incorporate some F1 elements (especially some of the mobility elements) into her workouts.
Are there any strength or mobility elements that would have a greater potential for injury for someone at her age (vs someone in their 20's or 30's)?