i recently injured my back lifting weights. There was pain for about a day, which eventually substided. Thereafter, about two weeks later, I noticed bruising on my lower back and back side of my calf after running. The bruises do not really appear when I am non-active, but when I run they are very noticable. Is there a correlation between the injury and these bruises or should I be concerned with another problem? The bruises are painless.