INTRODUCTION — Exercise headache is an uncommon headache syndrome characterized by brief episodes of head pain triggered by exercise.
This topic will discuss exercise headache, previously called exertional headache. Other uncommon headache syndromes characterized by recurrent episodes of brief pain are discussed separately.
●(See "Overview of thunderclap headache".)
●(See "Primary cough headache".)
●(See "Primary headache associated with sexual activity".)
●(See "Hypnic headache".)
●(See "Primary stabbing headache".)
●(See "Cold stimulus headache".)
ETIOLOGY — Headache provoked by exercise may occur either as a symptom of another disorder (secondary or symptomatic exercise headache) or as a primary disorder without an identifiable underlying abnormality (primary exercise headache). The relative frequency of primary versus secondary headaches differs from one case series to another. However, as neuroimaging techniques have improved, the proportion of symptomatic headaches relative to primary headaches has increased.
●In a case series from the 1960s, of 103 patients who presented with exercise (including cough-triggered) headache and a normal neurologic examination, an intracranial lesion developed in only 9.7 percent after three years of follow-up [1].
●In a literature review from the early 1990s, of 219 nonconsecutive patients with exercise headache that also included patients with cough headache, a structural lesion was found in 22 percent [2].
●In a series from the mid-1990s that included 28 consecutive patients with exercise headache, an intracranial abnormality was found in 12 (43 percent) [3]. The patients in this series with secondary headaches generally had symptoms strongly suggestive of an intracranial abnormality, including sudden explosive onset, vomiting, and focal neurologic deficits such as diplopia and papilledema.
The underlying abnormalities most commonly associated with exercise headache include the following [2,3]:
●Previous traumatic injury
●Supratentorial and posterior fossa space-occupying lesions (both metastatic and primary)
●Vascular abnormalities such as cerebral aneurysm or arteriovenous malformation
●Intracranial hemorrhage
Other types of paroxysmal headache that may be triggered by exertion include pheochromocytoma-related headache [4] and headache due to intermittent obstruction of cerebrospinal fluid flow caused by a third ventricular colloid cyst, lateral ventricular tumor, or Chiari type I malformation [2]. In addition, cardiogenic headache may be triggered by exertion in patients with risk factors for coronary disease, including those without chest pain or evidence of ischemia on electrocardiogram (ECG) [5]. Exercise is also a fairly common trigger in some migraineurs for their typical migrainous headaches.
PATHOPHYSIOLOGY — The pathophysiology of exercise headache is not well understood. As with cough headache, most theories center on the transmission of increases in intra-abdominal/intrathoracic pressure into the cranium via the venous system with distension of, or traction on, pain sensitive vascular or meningeal structures [6]. In some cases, it may share a common mechanism with migraine, since exertion is a trigger for migraine headaches in some individuals.
However, it is unclear why certain individuals become vulnerable to repeated activations of trigeminocervical nociceptive neurons, since similar transient increases in intracranial pressure due to Valsalva presumably occur in everyone. Possibilities include factors that cause lowered activation thresholds in first or second order nociceptive trigeminocervical neurons, alterations in central nociceptive processing, or factors that result in inordinately large fluctuations in intracranial pressure.
Another possibility is that incompetence of the internal jugular vein valve might play a role in the development of exercise headache by predisposing to increased cerebral venous congestion and elevated intracranial pressure during Valsalva maneuvers [7]. In support of this notion, a study employing venous duplex ultrasound compared 20 patients with exercise headache and 40 controls [7]. Retrograde jugular venous flow during Valsalva was significantly more frequent in patients with exercise headache than controls (70 versus 20 percent, respectively).
An alternative hypothesis suggested by transcranial Doppler studies is that exercise and sexual headache may be the result of impaired autoregulation of cerebrovascular smooth muscle. This dysregulation may impair the ability of resistance vessels to adequately respond to increased blood pressure during exercise, resulting in abnormal vasodilation, vessel wall edema, or increased cephalic blood volume [8].
CLINICAL FEATURES — Exercise headache is characterized by episodes of pulsatile head pain that are brought on by or occur only during or after physical exercise. Primary exercise headache is more likely to occur during hot weather or at high altitude [9].
Exercise headaches are bilateral and throbbing in quality. They persist from five minutes to 48 hours, are triggered by physical exercise, and may be prevented by avoidance of excessive physical exertion. Exercise headaches are not usually associated with nausea or vomiting [1]. It should be pointed out that the defining features of exercise headache come to us from a relatively small number of case series [1-3,8,10,11].
The precise incidence and prevalence of primary exercise headache are unknown, and estimates vary widely. A Danish population-based study of adults found that benign exercise headache had a lifetime prevalence of 1 percent [12], while a study of adults from Norway found a prevalence of approximately 12 percent [13]. In an Iranian general population cohort of 2300 people, exercise headache was more frequent in females compared with males (10.0 versus 5.4 percent) with an overall one-year prevalence of 7.3 percent (95% CI 6.2-8.4) [14]. One large series carried out in athletes (cyclists) estimated a considerably higher prevalence of 26 percent [15].
DIAGNOSIS — The diagnosis of primary exercise headache, according to the International Classification of Headache Disorders, 3rd edition (ICHD-3), requires fulfilling all of the following criteria [9]:
●At least two headache episodes
●Brought on by and occurring only during or after strenuous physical exercise
●Lasting <48 hours
●Not better accounted for by another ICHD-3 diagnosis
Distinguishing cough headache and exercise headache — Because Valsalva maneuvers frequently occur in the context of many forms of physical exertion, it is sometimes difficult to distinguish primary cough headache from primary exercise headache. (See "Primary cough headache".)
However, several clinical differences between benign cough and benign exercise headache have been identified that aid in distinguishing the two disorders [3]:
●Cough headache is triggered by Valsalva maneuvers, while exercise headache is triggered by more sustained physical exercise
●The average age of patients afflicted with benign cough headache is 67 (± 11), while the average age of patients with benign exercise headache is 24 (± 11)
●Primary cough headache typically has a faster onset than benign exercise headache, which builds up over minutes or longer
●Primary cough headaches are shorter in duration than benign exercise headaches
●Primary cough headaches are typically sharp and stabbing in quality while benign exercise headaches are described as pulsatile
EVALUATION — Patients with new or never-evaluated exercise headache should have an evaluation, including brain imaging and a neurovascular evaluation with intracranial magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA), or computed tomography (CT) and CT angiography (CTA), to rule out vascular abnormalities or other structural causes, particularly subarachnoid hemorrhage, cerebral or cervical arterial dissection, and reversible cerebral vasoconstriction syndrome [9]. The need for such investigations increases when the headaches appear de novo after the age of 40, are prolonged beyond a few hours, or are accompanied by vomiting or focal neurologic symptoms [16]. (See "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis" and "Cerebral and cervical artery dissection: Clinical features and diagnosis" and "Reversible cerebral vasoconstriction syndrome".)
Any symptoms suggestive of subarachnoid hemorrhage (SAH), including rapid onset, alteration in consciousness, or meningeal symptoms, argue for emergent evaluation. (See "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis", section on 'Evaluation and diagnosis'.)
Patients who have exercise-induced headache and cardiovascular risk factors should have an evaluation for coronary heart disease, particularly if headache occurs exclusively with exercise, lacks features suggestive of migraine, or radiates to or from the neck or jaw [5]. (See "Screening for coronary heart disease".)
Once other causes (eg, structural, cerebrovascular, and cardiovascular) of exercise headache have been eliminated, treatment should be started.
TREATMENT — Treatment of exercise headaches is usually prophylactic or preemptive when exercise is predictable. Indomethacin is the de facto drug of choice for benign exercise headaches, although supporting evidence is mainly anecdotal [17,18]. The therapeutic dose may range from 25 to 150 mg per day, although higher doses up to 250 mg may be necessary. Indomethacin can be used daily, but we suggest dosing 30 to 60 minutes before activity/exercise unless headaches are activated on an almost daily basis. The mechanism of indomethacin's benefit in these syndromes is not known, although its effect on cerebrospinal fluid pressure has been suggested [19]. Propranolol [3], naproxen, phenelzine, and ergonovine have also been reported to be beneficial in some patients [20].
Data are limited regarding the long-term prognosis of primary exercise headache. In one series that followed 93 patients, complete remission of headache within five years was observed in 32 percent, and significant improvement or complete remission after 10 years was noted in 78 percent [1].
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Migraine and other primary headache disorders".)
SUMMARY AND RECOMMENDATIONS
●Exercise headache is characterized by episodes of bilateral, pulsatile head pain that are brought on by, or occur only during or after, physical exercise. Headaches last five minutes to 48 hours, and may be prevented by avoidance of excessive physical exertion. (See 'Clinical features' above.)
●Because Valsalva maneuvers frequently occur in the context of many forms of physical exertion, it is sometimes difficult to distinguish primary cough headache from primary exercise headache. (See 'Distinguishing cough headache and exercise headache' above.)
●For patients with new or never-evaluated exercise headache, we recommend brain imaging and neurovascular studies to exclude structural and cerebrovascular causes, particularly subarachnoid hemorrhage, cerebral and cervical arterial dissection, and reversible cerebral vasoconstriction syndrome. (See 'Etiology' above and 'Evaluation' above.)
●We recommend an evaluation for coronary heart disease if the patient has cardiovascular risk factors. (See 'Etiology' above and 'Evaluation' above.)
●For patients who develop exercise headache predictably, we suggest treatment with indomethacin 25 to 150 mg per day, given as needed 30 to 60 minutes before activity/exercise (Grade 2C). Indomethacin can be used every day for patients whose headaches are activated on an almost daily basis. Alternative medications that may be effective for exercise headache are propranolol, naproxen, phenelzine, and ergonovine. (See 'Treatment' above.)
