The importance of maintaining good posture when running
When we run we want to maintain a strong posture through the core and back so that our skeleton frame can support most of our weight.
When we hinge at the waist (often due to pore core stability and strength) we put undo stress on our hips and back. A good thing to think about is running proud or tall with your line of sight forward.
The body will often follow what the head and eyes are doing so if you notice that you are looking down or that your head is slightly dropped change it so you are looking up and standing tall, standing proud.