Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

OBJECTIVE: To examine whether aerobic fitness moderated age differences in within-person reaction time variability (WP RT variability) and given conceptual linkage involving the frontal cortex, whether effects were mediated by executive function. METHOD: Aerobic fitness (estimated VO2max) and WP RT variability were investigated in 225 healthy, community-dwelling adults aged 50-90 years (M = 63.83) across 4 cognitive domains; psychomotor performance, executive function, visual search, and recognition. RESULTS: Significant Age × Aerobic fitness interactions were found in relation to WP variability in 3 cognitive domains: psychomotor performance (4-choice RT), executive function (Flanker and Stroop arrows), and immediate recognition. Lower aerobic fitness was associated with greater RT variability, and this effect increased with age. Additionally, some of these effects were mediated by executive function. DISCUSSION: The findings suggest that aerobic fitness moderated the association between age and intraindividual RT variability, and that executive function selectively mediated that association. It is possible that aerobic fitness helps attenuate the neurobiological decline that contributes to cognitive deficits in old age and that WP variability is a measure that may be particularly sensitive to this effect.

Original publication




Journal article


J Gerontol B Psychol Sci Soc Sci

Publication Date





431 - 438


Aerobic fitness, Age, Cognitive function, Intraindividual variability, Physical activity, Reaction time, Aged, Aged, 80 and over, Aging, Attention, Executive Function, Exercise Test, Female, Frontal Lobe, Humans, Individuality, Male, Middle Aged, Neuropsychological Tests, Oxygen, Physical Fitness, Psychomotor Performance, Reaction Time, Recognition, Psychology, Stroop Test