Running injuries are primarily caused by overuse due to training errors (i.e., running too far, too fast, too soon). A stress fracture should always be considered in a runner with pain, because long-term morbidity may occur if this injury is not recognized. The history and physical examination are usually sufficient to diagnose an overuse injury. Runners should be instructed to increase their mileage gradually in increments of 10 percent or less each week, to wear proper running shoes and to perform stretching and strengthening exercises for the lower extremities on a regular basis. In addition, they should not attempt to "run through pain." Treatment of overuse running injuries includes relative rest, nonsteroidal anti-inflammatory drugs, cross-training and stretching exercises, with a return to running as tolerated. Correction of biomechanical problems with the use of orthotics may be an adjunctive treatment measure.