The most common running injuries are runner’s knee, stress fractures, Achilles tendonitis, pulled muscles, sprained ankles, shin splints and plantar fasciitis. Over 80 percent of runners experience these injuries each year. As a high-impact activity, running places a lot of stress on joints and muscles. While some soreness and mild pain are common, you should seek immediate medical attention for any swelling, redness or stiffness, and for any persistent, nagging, or severe pain or discomfort. To prevent common running-related foot problems, be sure to warm up your muscles and joints before you run, listen to your body, know your limits and go see a doctor or physical therapist when you notice any sign of injury.