Regular weight-bearing exercise can preserve bone mass and conserve or improve BMD in older adults (Heinonen A, 1999; Snow CM, 2000; Ulrich CM, 1999; Wolff I, 1999) and could also reduce hip fracture risk by decreasing the risk of fall in the elderly population (Gregg EW, 2000; Kujala UM, 2000).
Examples of weight-bearing exercise include walking, Tai Chi, and using elliptical trainers. Walking has clinical benefits for pain, functional status, disability in ADLs, energy level, medication, aerobic capacity, and quality of life (Brosseau L, 2005). Tai Chi seems to have a positive effect in reducing falls (Gillespie LD, 2003; Verhagen AP, 2004). Elliptical training machines are low impact because your feet never leave the pads, and the smooth movement would seem to produce less stress on your joints than a treadmill.