Like stress fractures, shin splints are most common among newer runners. This could be from improper running technique, being overweight or from overtraining (yes, that old chestnut) and is sometimes known as medial tibial stress syndrome. This sometimes-excruciating injury occurs when repeated stress from running inflames the tissue surrounding the tibia.
If you're suffering from this problem, avoid running for a few days. You don't have to stay off your feet completely, but avoid the exercise that caused the injury to keep it from getting worse. Make sure it's not a stress fracture, too, which could lead to more concerns.
Stretching and training exercises to increase your flexibility and strength will help prevent this from recurring [source: Wharton].