what causes soreness in legs
1 Pain in the legs may be due to injury or inflammation of any of the structures that are found in the leg, including bones, joints, muscles, tendons, ligaments, blood vessels, nerves, and skin. Inflammation of tissue is usually the cause of pain.  Pain can also radiate from other parts of the body and be felt in the leg. Back ailments can cause pain and numbness of the leg. Abdominal aorta and iliac artery aneurysms can also present with leg pain. A blood clot in the large veins located in the abdomen, pelvis, or legs is another cause of leg symptoms.
1 Repetitive, excessive sports, especially in the form on running, can lead to trauma that creates leg pain - E.G: shin splints and stress fractures. 2  Leg pain with an underlying medical cause may be nerve-related, musculoskeletal or vascular.  Some forms of leg pain resolve with self-help care.