You, Too, Can Grow Fresh, New Bone
Bone weakening is a common problem associated with aging. In most people, sometime during your 30s, your bone mass will begin to decline gradually. Exercise, however, naturally builds stronger bones.
Your bones are constantly being rebuilt in a dynamic process involving the removal of old bone through osteoclasts and regeneration of new, healthy bone by osteoblasts. Load-bearing exercise works to build stronger bones by stimulating cells responsible for the synthesis and mineralization of bone (osteoblasts). Weight-bearing is one of the most effective remedies against osteoporosis, because as you put more tension on your muscles it puts more pressure on your bones, which then responds by continuously creating fresh, new bone. It can go a long way to prevent brittle bone formation and help to reverse damage already done.
Weight bearing exercises include activities like walking, jogging, stair climbing, biking, dancing, yoga, weight lifting, strength training exercises and impact-producing sports. Vary your weight bearing activities to exercise all your muscles and joints.
— Source: Mercola.com