Exercise for healthy bones

Exercise.  Ouch, now my toes are being tromped on.  Exercise, who me?  Do I have to? Yes unless I want to be a stooped, round-shouldered little old woman. 

Weight bearing and muscle-strengthening exercises will help my bones stay healthy and help prevent me from falling and suffering a painful fracture.  Weight bearing uses weight to add resistance.  We can use weights, resistance bands, exercise machines, even our own body weight.  A friend and co-worker recently shared that since she began running (exercise), that her bone density studies have improved into a normal level and her doctor took her off the osteoporosis medication she was taking.  Can exercise be a significant treatment for osteoporosis?  It is for my friend.  My friend who is running has begun what is called high-impact weight-bearing exercises.  Other examples include dancing, hiking, jogging, tennis, jumping rope, and climbing stairs.  Low-impact weight-bearing exercises (more my speed) include fast walking, elliptical machines, low-impact aerobics and stair-stepper machines.  Muscle-strengthening exercises include lifting weights, using exercise bands or weight machines, and even lifting your own body weight.