Elevated Aerobic Fitness Sustained Throughout the Adult Lifespan Is Associated With Improved Cerebral Hemodynamics

Bailey, Damian Miles; Marley, Christopher J.; Brugniaux, Julien V.; Hodson, D; New, Karl J.; Ogoh, Shigehiko; Ainslie, Philip N.

doi:10.1161/strokeaha.113.002589

Cited by 186 publications

(232 citation statements)

References 16 publications

Supporting

Mentioning

206

Contrasting

Unclassified

Order By: Relevance

“…Individuals who are taking antihypertensive medications or participating in regular exercise were excluded for their potential impact on cerebral and central hemodynamics. [12][13][14] This study was approved by the Institutional Review Board of the University of Texas Southwestern Medical Center and Texas Health Presbyterian Hospital Dallas, and was performed in accordance with the guidelines of the Declaration of Helsinki and Belmont Report. All subjects gave informed written consent before participation.…”

Section: Study Participantsmentioning

confidence: 99%

Cerebral Hemodynamics in Normal Aging: Central Artery Stiffness, Wave Reflection, and Pressure Pulsatility

Tarumi

Khan

Liu

et al. 2014

J Cereb Blood Flow Metab

177

143

View full text Add to dashboard Cite

Blood ejected from the left ventricle perfuses the brain via central elastic arteries, which stiffen with advancing age and may elevate the risk of end-organ damage. The purpose of this study was to determine the impact of central arterial aging on cerebral hemodynamics. Eighty-three healthy participants aged 22 to 80 years underwent the measurements of cerebral blood flow (CBF) and CBF velocity (CBFV) using magnetic resonance imaging (MRI) and transcranial Doppler, respectively. The CBF pulsatility was determined by the relative amplitude of CBFV to the mean value (CBFV%). Central arterial stiffness (carotid-femoral pulse wave velocity), wave reflection (carotid augmentation index), and pressure were measured using applanation tonometry. Total volume of white-matter hyperintensity (WMH) was quantified from MR images. Total CBF decreased with age while systolic and pulsatile CBFV% increased and diastolic CBFV% decreased. Women showed greater total CBF and lower cerebrovascular resistance than men. Diastolic CBFV% was lower in women than in men. Age-and sex-related differences in CBF pulsatility were independently associated with carotid pulse pressure and arterial wave reflection. In older participants, higher pulsatility of CBF was associated with the greater total volume of WMH. These findings indicate that central arterial aging has an important role in age-related differences in cerebral hemodynamics.

show abstract

Section: Study Participantsmentioning

confidence: 99%

Cerebral Hemodynamics in Normal Aging: Central Artery Stiffness, Wave Reflection, and Pressure Pulsatility

Tarumi

Khan

Liu

et al. 2014

J Cereb Blood Flow Metab

177

143

View full text Add to dashboard Cite

show abstract

“…Recent studies (4, 49) also reported a lack of an association between fitness and MCAv mean in young vs. older individuals. In contrast, life-long physical activity/training has shown an attenuated age-dependent decline in resting MCAv mean (2,3) and CBF (2,3,46). When the same relative exercise intensities were compared the trained study participants displayed a higher PaCO 2 in the control trial, and this was independent of age.…”

Section: Discussionmentioning

confidence: 87%

“…Whether fitness is a factor affecting CBF during exercise remains unclear. Moreover, aerobic fitness may affect hypercapnic cerebrovascular reactivity (4,32,49), although these findings are also contradictory as increased (3,32), unchanged (49) and decreased (46) hypercapnic reactivity has been reported in aerobically trained individuals. Again potential influencing factors for the widespread results could include differences in age and fitness levels across studies.…”

mentioning

confidence: 96%

“…One reason for the discrepancies could be related to the use of humans over a narrow age range, and with varying degrees of physical fitness. Thus a further aim related to this study was to quantify CO 2 reactivity and to investigate its association to the decrease in MCAv mean with age.A high aerobic fitness level appears to attenuate the agerelated decline in resting CBF (39) and MCAv mean (1)(2)(3)46), although this has not been universally observed (4, 49). …”

mentioning

confidence: 99%

“…A high aerobic fitness level appears to attenuate the agerelated decline in resting CBF (39) and MCAv mean (1)(2)(3)46), although this has not been universally observed (4,49). Whether fitness is a factor affecting CBF during exercise remains unclear.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Age, aerobic fitness, and cerebral perfusion during exercise: role of carbon dioxide

Flück

Bráz

Keiser

et al. 2014

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Middle cerebral artery mean velocity (MCAvmean) is attenuated with increasing age both at rest and during exercise. The aim of this study was to determine the influence of the age-dependent reduction in arterial PCO2 (PaCO2) and physical fitness herein. We administered supplemental CO2 (CO2 trial) or no additional gas (control trial) to the inspired air in a blinded and randomized manner, and assessed middle cerebral artery mean flow velocity during graded exercise in 1) 21 young [Y; age 24 Ϯ 3 yr (ϮSD)] volunteers of whom 11 were trained (YT) and 10 considered untrained (YUT), and 2) 17 old (O; 66 Ϯ 4 yr) volunteers of whom 8 and 9 were considered trained (OT) and untrained (OUT), respectively. A resting hypercapnic reactivity test was also performed. MCAvmean and PaCO2 were lower in O [44.9 Ϯ 3.1 cm/s and 30 Ϯ 1 mmHg (ϮSE)] compared with Y (59.3 Ϯ 2.3 cm/s and 34 Ϯ 1 mmHg, P Ͻ 0.01) at rest, independent of aerobic fitness level. The age-related decreases in MCAvmean and PaCO2 persisted during exercise. Supplemental CO2 reduced the age-associated decline in MCAv mean by 50%, suggesting that PaCO2 is a major component in the decline. On the other hand, relative hypercapnic reactivity was neither influenced by age (P ϭ 0.46) nor aerobic fitness (P ϭ 0.36). Although supplemental CO2 attenuated exercise-induced reduction in cerebral oxygenation (near-infrared spectroscopy), this did not influence exercise performance. In conclusion, PaCO2 contributes to the age-associated decline in MCAvmean at rest and during exercise; however exercise capacity did not diminish this age effect. brain blood flow; middle cerebral artery; old; transcranial Doppler CEREBRAL BLOOD FLOW (CBF) is meticulously regulated to ensure an adequate perfusion of the brain. With exercise middle cerebral artery mean velocity (MCAv mean ; a surrogate measure of CBF) is increased until ϳ60% of maximal oxygen uptake (V O 2max ) but thereafter declines toward resting levels (10,20,28). In young healthy individuals this drop in cerebral perfusion is likely the consequence of a hyperventilation facilitated reduction in PaCO 2 and hence augmented cerebral vasoconstriction (39). Accordingly, administration of CO 2 to the inspired air during exercise abolishes the decrease in MCAv mean (44,45), and during vigorous exercise MCAv mean is regulated by PaCO 2 and only to a lesser extent influenced by cerebral metabolism, mean arterial pressure (MAP), cardiac output, or sympathetic nerve activity (35).Compared with young healthy individuals a reduced CBF (24) and MCAv mean has consistently been reported in the aged population both at rest (2,7,9,15,25,27,49) and during exercise (9,10,28,32). Although a reduced MCAv mean response in aged humans is observed with exercise, its pattern follows that of young individuals, i.e., an initial increase which is then followed by a decline as the exercise intensity becomes intense (9,10,28,32). The regulating mechanisms for the reduction in CBF with age remain uncertain and global brain atrophy (11), decreased neuronal activ...

show abstract

Measuring resting cerebral haemodynamics using MRI arterial spin labelling and transcranial Doppler ultrasound: Comparison in younger and older adults

et al. 2021

View full text Add to dashboard Cite

show abstract

Elevated Aerobic Fitness Sustained Throughout the Adult Lifespan Is Associated With Improved Cerebral Hemodynamics

Cited by 186 publications

References 16 publications

Cerebral Hemodynamics in Normal Aging: Central Artery Stiffness, Wave Reflection, and Pressure Pulsatility

Cerebral Hemodynamics in Normal Aging: Central Artery Stiffness, Wave Reflection, and Pressure Pulsatility

Age, aerobic fitness, and cerebral perfusion during exercise: role of carbon dioxide

Measuring resting cerebral haemodynamics using MRI arterial spin labelling and transcranial Doppler ultrasound: Comparison in younger and older adults

Contact Info

Product

Resources

About