4.6.3 Probable external-pressure headache

A 31-year-old competitive cyclist reports three such episodes over the past year, always beginning around ninety minutes into a long ride. Each time her cycling helmet's chin strap and rear cradle were pressing steadily on her forehead, and midway through the ride she had re-tightened her ponytail, producing a pulling sensation on her scalp that began only after the head pain had already set in. The ache was consistently worst directly beneath the helmet strap, at the exact spot of contact, rather than spreading more widely. On each occasion the discomfort persisted for a good two hours after she removed the helmet and let her hair down at the finish, before gradually easing. She reports no nausea, vomiting, photophobia or visual symptoms with these episodes, and no associated dizziness.