The main cause of a groin stress fracture is excessive or repetitive stress on the bones. This can happen due to activities that involve running, jumping, or sudden changes in direction, such as in sports like soccer, basketball, or track and field. Overtraining, inadequate rest periods, improper technique, or changes in training intensity or surface can also contribute to the development of stress fractures. Here is more information about groin stress fracture symptoms and what to do about it.