Ligaplex I by Standard Process is a natural food-based supplement that does not come with the typical side effects of most medications. In other words, the supplements are concentrated food stuffs, that in turn have the appropriate ratio of nutrients in them. Each formulation through Standard Process would have food stuffs in it that is specific to the body tissues, such as joint or heart, etc, that helps to support that respective tissue. They are wonderful products and Standard Process has been around since the 1920's and are essentially the "original" supplement company, out there long before anyone else. I suggest you explore their website, www.standardprocess.com for more information on their rich history and excellent products.
Due to the amount of exercise that you undergo, I would consider adding Ligaplex II, which is specifically designed for people who undergo strenous exercise.
Be safe and be sure to mention all of this to your doctor. Be sure that you are not overtraining either. Remember it is ok to take a break from running once in a while to allow your joints to rest and recover.