I just tried to run thirty minutes for cardio, and my lower back actually began to cramp. Is this related to kidney pain/problems? Because it doen't feel like it. The muscles of my lower back just fel pumped so tight it's painfull. And, I haven't been having any muscle soreness, or other back pain. Is this related to water retention? Could it be remedied with glycerin, or a mild dieuretic like dandelion root?
Anyone else have these painfull lower back pumps?