I have had some mild osteoporosis in my left hip for several years, but with very little discomfort. However, in the last couple of weeks, the level of discomfort has suddenly ramped up significantly, and I am feeling a high degree of discomfort when walking. I have a regular exercise routine daily, and have found that my walking on the treadmill is hurting a great deal. The elliptical machine is much easier and not painful. Should I stop walking on the treadmill (and outdoor walking as well)?