Exercise and Prevention of Syncope: EXPOSE

The purpose of this study is to determine whether eight weeks of exercise performed at an intensity of approximately 65% VO2max will improve symptoms associated with fainting (vasovagal syncope).

Background: Vasovagal syncope affects 20-30% of the population, and for those who faint recurrently it causes a significant reduction in the quality of life. Although significant progress has been made in the past 15 years in our understanding of its diagnosis and prognosis, our therapeutic attempts often end in failure. Many patients who have been diagnosed with vasovagal syncope have a reduced orthostatic tolerance. Improved orthostatic tolerance has been achieved through exercise in a number of studies on healthy individuals. However, its efficacy as a means of treatment for those with vasovagal syncope has not been thoroughly explored. Comparison: Subjects will be randomized to one of two groups: an exercise group or control. The exercise group will be asked to train at a target of approximately 65% of their maximum exercise capacity (VO2max) for 8 weeks/3 times per week. The control group will be asked to perform a series of neck rotation exercises. Orthostatic tolerance will be examined in both groups pre and post intervention.

exercise, total peripheral resistance, venoconstriction, blood volume expansion, orthostatic tolerance

Inclusion Criteria: a diagnosis of vasovagal syncope as the cause of loss of consciousness, >1 lifetime syncope spell preceding enrolment, >-3 points on the S3 score for structurally normal hearts, >18 yrs of age with informed consent - Exclusion Criteria: subjects with a negative Physical Activity Readiness Questionnaire (PARQ), those who are unable to provide informed consent, those with a VO2max >55ml/kg/min, those who exercise more than 30 minutes per day, 3 times per week, other causes of syncope, individuals with valvular, coronary, myocardial, or conductive abnormality, significant arrhythmia, hypertrophic cardiomyopathy, permanent pacemaker, seizure disorder, heart failure, major chronic cardiovascular disease, or renal dysfunction. -