Stress fracture

A stress fracture is a small crack in a bone caused by repeated load. It needs a doctor: stop running and get it checked.

• Signs: pain in one precise spot you can point to with a finger, sore when pressed, coming earlier in each run, then when walking, at rest or at night; sometimes swelling.
• Usual sites: the shin, the bones of the foot, the heel, the hip.
• Common causes: a sharp rise in training, not eating enough for the training you do, missed periods, low vitamin D, a previous fracture.
• Healing usually takes 6 to 8 weeks without running, longer for the hip or some foot bones, followed by a gradual walk-run return.

Pain in the groin or hip that worsens with running needs a doctor quickly.