title: Cognitive compromise following exercise in monozygotic twins discordant for chronic fatigue syndrome: fact or artifact?
abstract: This study examined the effects of exhaustive exercise on cognitive functioning among 21 monozygotic twin pairs discordant for chronic fatigue syndrome (CFS). The co-twin control design adjusts for genetic and family environmental factors not generally accounted for in more traditional research designs of neuropsychological function. Participants pedaled a cycle ergometer to exhaustion; maximum oxygen output capacity (VO2max) as well as perceived exertion were recorded. Neuropsychological tests of brief attention and concentration, speed of visual motor information processing, verbal learning and recognition memory, and word and category fluency were administered with alternate forms to participants pre- and postexercise. The preexercise neuropsychological test performance of CFS twins tended to be slightly below that of the healthy twin controls on all measures. However, twins with CFS did not demonstrate differential decrements in neuropsychological functioning after exercise relative to their healthy co-twins. Because exercise does not appear to diminish cognitive function, rehabilitative treatment approaches incorporating exercise are not contraindicated in CFS.
authors.affiliation: Departments of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA.
authors.forename: K
authors.initials: K
authors.lastname: Claypoole
authors.forename: R
authors.initials: R
authors.lastname: Mahurin
authors.forename: M E
authors.initials: ME
authors.lastname: Fischer
authors.forename: J
authors.initials: J
authors.lastname: Goldberg
authors.forename: K B
authors.initials: KB
authors.lastname: Schmaling
authors.forename: R B
authors.initials: RB
authors.lastname: Schoene
authors.forename: S
authors.initials: S
authors.lastname: Ashton
authors.forename: D
authors.initials: D
authors.lastname: Buchwald
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology; D015444:Exercise / Q000523:psychology*; D005081:Exercise Therapy; D015673:Fatigue Syndrome, Chronic / Q000235:genetics / Q000523:psychology* / Q000534:rehabilitation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D013647:Task Performance and Analysis; D014430:Twins, Monozygotic