I've been using the elliptical machine at the gym for almost a year now, but just recently, I've noticed that my knee has been hurting, but I usually feel the pain when I'm going downstairs or downhill (when I'm hiking). When I press the kneecap, I can feel like a "pinching" pain around the soft areas on the front of my knee. I'm usually on the elliptical machine for an hour every other day, but since I had to rest my knee, I've noticed I'm gaining weight now! Is this runner's knee that I have? What exercises can I do besides the elliptical for my condition? Can I walk instead? Thanks much!