I'm 64 with 3 children. I started exercising when I retired 3 years ago as I was stiff, arthritic and had RSI. I did a weekly exercise class, a weekly swim and walked 10,000 a day. I had to stop at the beginning of the year due to severe prolapse. I had a hysterectomy and repair in February and back to walking but not swimming or exercise class. I will have to avoid some exercises (and heavy lifting) for life, as I don't want another prolapse. I think we have to keep active, even if it's housework and gardening rather than formal exercise, once we retire. I don't think I would age well if I was a couch potato.