A bone stress injury (BSI) is an overuse injury whereby the bone is loaded more than it can tolerate and that causes pain that increases with running and does not decrease after warming up (as a tendon injury does).
BSIs are common in runners. New research is showing that decreased bone mineral density (BMD) and prior BSIs appear to be at least as common in the adult ultrarunner population as in the collegiate runner population.
BSIs occur due to modifiable extrinsic and intrinsic risk factors related to training and health. Adequate caloric intake, calcium intake, vitamin D levels, and a regular menstrual cycle in women, in addition to participation in weight-bearing sports, are all important for your bone heath.
Do not ignore BSI warning signs. If you have pain that does not warm up with running or increases, seek medical care. Identifying a BSI early may prevent a fracture and/or shorten your recovery time.