Blood Flow and Bone Density in Healthy Adult Women

Women between the ages of 30 and 60 years of age who work in positions that require them to be seated at desks for a large portion of each day, are capable of following the protocol for one year, have a t-score \>- 2.5 (do not have osteoporosis), and respond to plantar stimulation will be asked to participate. Women will be excluded who are receiving medications for osteoporosis, taking hormone replacement therapy, taking steroids (either oral or inhaled), have metal implants in the tibia, hip and spine that interfere with DEXA (bone density) scanning, are professional or semi-professional athletes, have hyperparathyroidism, have a history of pulmonary embolism, deep vein thrombosis, peripheral vascular disease or varicose veins, have a Body Mass Index greater than 40 Kg/m2, have any type of neuromuscular disease, or are pregnant . Once the inclusion and exclusion criteria are met, 45 subjects will be randomized into 3 groups including 1) a group of 15 subjects who will use the device (stimulation) for up to 4 hours a day, 2) a group of 15 subjects that will use the device for up to 8 hours a day, and 3) a control group who will not use the device. Subjects in the two treatment groups will be asked to place their feet on a mechanical device that will deliver a slight vibration while they are seated at work. Vibrations between 30-60 Hz has been shown to stimulate the Meissner's corpuscles which in turn stimulate contraction of the deep muscles of the calves. This contraction has been shown to increase venous and lymphatic return from the lower extremities thus improve bone metabolism. Bone density readings and venous circulation will be measured at the onset of this research and will be repeated after 12 months of using the device.