Chronic stiffness in your hip flexors can cause lower back discomfort in addition to generating muscular tension or achiness. If these strong muscles become too tight, they can force the pelvis forward, causing lower back discomfort. Inflammation of the growth plate can produce pain below the knee (on the top of your tibia). Learn more about Osgood-disease Slatter's diagnosis and treatment in this article. What to do: If the discomfort goes away while jogging, you may train through it. Shortening your stride and quickening your cadence can assist.