Long-term Exercise Confers Equivalent Neuroprotection in Females Despite Lower Cardiorespiratory Fitness. (10th February 2020)

• Record Type: Journal Article
• Authors: Marley, Christopher J.; Brugniaux, Julien V.; Davis, Danielle; Calverley, Thomas A.; Owens, Thomas S.; Stacey, Benjamin S.; Tsukamoto, Hayato; Ogoh, Shigehiko; Ainslie, Phillip N.; Bailey, Damian M.
• Is Part Of: Neuroscience. Volume 427(2020)
• Page Start: 58
• Page End: 63
• Publication Date: 2020-02-10
• Subjects: CBF cerebral blood flow -- CRF cardiorespiratory fitness -- CVCi conductance indices -- CVRCO2 cerebrovascular reactivity to carbon dioxide -- CVRi Cerebrovascular resistance -- MAP mean arterial pressure -- MCAv middle cerebral artery velocity -- VO2MAX maximal oxygen consumption; cerebral haemodynamics -- exercise -- neuroprotection -- sex; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2019.12.008
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: To what extent regular exercise confers neuroprotection in females remains less established than in males. Compared to their male counterparts, untrained females are characterized by improved cerebrovascular function. Despite this, regular exercise conferred equivalent neuroprotection across sexes in the form of elevated CVRCO2 . These findings highlight the neuroprotective benefits of regular exercise that do not appear to be sex-specific. Regular exercise could help combat the accelerated trajectory towards cerebrovascular disease in females in later life. Abstract: Females are more prone to cognitive decline, stroke and neurodegenerative disease, possibly due to more marked reductions in cerebral blood flow and cerebrovascular reactivity to CO2 (CVRCO2HYPER ) in later life. To what extent regular exercise confers selective neuroprotection in females remains unestablished. To examine this, 73 adults were prospectively assigned to 1 of 4 groups based on sex (male, ♂ vs. female, ♀) and physical activity status (trained, ≥150 min of moderate-vigorous intensity aerobic exercise/week; n = 18♂ vs. 18♀ vs. untrained, no formal exercise; n = 18♂ vs. 19♀). Middle cerebral artery velocity (MCAv, transcranial Doppler ultrasound), mean arterial pressure (MAP, finger photoplethysmography) and end-tidal CO2 (capnography) were assessed at rest during normocapnea and hypercapnea (5% CO2 ) enabling CVRCO2HYPER to be assessed. Cerebrovascular resistance/conductance indices (CVRi/CVCi) were calculated as MAP/MCAv and MCAv/MAP. Maximal oxygen uptake (VO2MAX ) was determined during incremental semi-recumbent cycling ergometry to volitional exhaustion. Despite having a lower VO2MAX, females were characterized by selective elevations in MCAv, CVRCO2HYPER and lower CVRi ( P < 0.05), but the training responses were similar across sexes. Linear relationships were observed between VO2MAX and CVRCO2HYPER (pooled untrained and trained data; ♂ r = 0.70, ♀ r = 0.51; both P < 0.05) with a consistent elevation in the latter equivalent to ∼1.50%.mmHg −1 compared to males across the spectrum of cardiorespiratory fitness. These findings indicate that despite having comparatively lower levels of cardiorespiratory fitness, the neuroprotective benefits of regular exercise translate into females and may help combat cerebrovascular disease in later life.