Morning exercise mitigates the impact of prolonged sitting on cerebral blood flow in older adults

Preventing declines in cerebral blood flow is important for maintaining optimal brain health with aging. We compared the effects of a morning bout of moderate-intensity exercise, with and without subsequent light-intensity walking breaks from sitting, on cerebral blood velocity over 8 h in older adults. In a randomized crossover trial, overweight/obese older adults ( n = 12, 70 ± 7 yr; 30.4 ± 4.3 kg/m2), completed three acute conditions (6-day washout); SIT: prolonged sitting (8 h, control); EX+SIT: sitting (1 h), moderate-intensity walking (30 min), followed by uninterrupted sitting (6.5 h); and EX + BR: sitting (1 h), moderate-intensity walking (30 min), followed by sitting (6.5 h) interrupted with 3 min of light-intensity walking every 30 min. Bilateral middle cerebral artery velocities (MCAv) were determined using transcranial Doppler at 13 time points across the day. The temporal pattern and average MCAv over 8 h was determined. The pattern of MCAv over 8 h was a negative linear trend in SIT ( P < 0.001), but a positive quadratic trend in EX + SIT ( P < 0.001) and EX + BR ( P < 0.01). Afternoon time points in SIT were lower than baseline within condition ( P ≤ 0.001 for all). A morning dip in MCAv was observed in EX + SIT and EX + BR ( P < 0.05 relative to baseline), but afternoon time points were not significantly lower than baseline. The average MCAv over 8 h was higher in EX + SIT than SIT ( P = 0.007) or EX + BR ( P = 0.024). Uninterrupted sitting should be avoided, and moderate-intensity exercise should be encouraged for the daily maintenance of cerebral blood flow in older adults. The clinical implications of maintaining adequate cerebral blood flow include the delivery of vital oxygen and nutrients to the brain. NEW & NOTEWORTHY This is the first study to measure the combined effects of an exercise bout with breaks in sitting on cerebral blood velocity in older adults. Using frequent recordings over an 8-h period, we have performed a novel analysis of the pattern of cerebral blood velocity, adjusting for concurrent measures of mean arterial pressure and other potential confounders in a linear mixed effects regression.

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Distinct effects of acute exercise and breaks in sitting on working memory and executive function in older adults: a three-arm, randomised cross-over trial to evaluate the effects of exercise with and without breaks in sitting on cognition

British Journal of Sports Medicine ◽

10.1136/bjsports-2018-100168 ◽

2019 ◽

Vol 54 (13) ◽

pp. 776-781 ◽

Cited By ~ 7

Author(s):

Michael J Wheeler ◽

Daniel J Green ◽

Kathryn A Ellis ◽

Ester Cerin ◽

Ilkka Heinonen ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Executive Function ◽

Light Intensity ◽

Visual Learning ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Intermittent Light ◽

Time Points ◽

Serum Bdnf

BackgroundSedentary behaviour is associated with impaired cognition, whereas exercise can acutely improve cognition.ObjectiveWe compared the effects of a morning bout of moderate-intensity exercise, with and without subsequent light-intensity walking breaks from sitting, on cognition in older adults.MethodsSedentary overweight/obese older adults with normal cognitive function (n=67, 67±7 years, 31.2±4.1 kg/m2) completed three conditions (6-day washout): SIT (sitting): uninterrupted sitting (8 hours, control); EX+SIT (exercise + sitting): sitting (1 hour), moderate-intensity walking (30 min), uninterrupted sitting (6.5 hours); and EX+BR (exercise + breaks): sitting (1 hour), moderate-intensity walking (30 min), sitting interrupted every 30 min with 3 min of light-intensity walking (6.5 hours). Cognitive testing (Cogstate) was completed at four time points assessing psychomotor function, attention, executive function, visual learning and working memory. Serum brain-derived neurotrophic growth factor (BDNF) was assessed at six time points. The 8-hour net area under the curve (AUC) was calculated for each outcome.ResultsWorking memory net AUC z-score·hour (95% CI) was improved in EX+BR with a z-score of +28 (−26 to +81), relative to SIT, −25 (−79 to +29, p=0.04 vs EX+BR). Executive function net AUC was improved in EX+SIT, −8 (− 71 to +55), relative to SIT, −80 (−142 to −17, p=0.03 vs EX+SIT). Serum BDNF net AUC ng/mL·hour (95% CI) was increased in both EX+SIT, +171 (−449 to +791, p=0.03 vs SIT), and EX+BR, +139 (−481 to +759, p=0.045 vs SIT), relative to SIT, −227 (−851 to +396).ConclusionA morning bout of moderate-intensity exercise improves serum BDNF and working memory or executive function in older adults, depending on whether or not subsequent sitting is also interrupted with intermittent light-intensity walking.Trial registration numberACTRN12614000737639.

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Self-Reported Omega-3 Supplement Use Moderates the Association between Age and Exercising Cerebral Blood Flow Velocity in Older Adults

Nutrients ◽

10.3390/nu12030697 ◽

2020 ◽

Vol 12 (3) ◽

pp. 697

Author(s):

Carolyn S. Kaufman ◽

Eric D. Vidoni ◽

Jeffrey M. Burns ◽

Mohammed R. Alwatban ◽

Sandra A. Billinger

Keyword(s):

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Blood Flow Velocity ◽

Multiple Linear Regression Model ◽

Transcranial Doppler Ultrasound ◽

Moderate Intensity ◽

Omega 3 ◽

Moderate Intensity Exercise ◽

Supplement Use

Cerebral blood flow (CBF) decreases across the lifespan, and chronic conditions such as dementia and stroke accelerate this decline. Impaired CBF results in reduced delivery of oxygen and nutrients, which can damage the brain over time. Thus, there is a need to identify lifestyle interventions, including diet and exercise, to maintain CBF with aging and in the presence of chronic disease. In the present study, we used transcranial Doppler ultrasound to record middle cerebral artery velocity (MCAv), a surrogate measure of CBF, during moderate-intensity exercise in sedentary, cognitively normal older adults (n = 90). A multiple linear regression model (F(4, 85) = 3.21, p = 0.02) showed that self-reported omega-3 supplement use significantly moderated the association between age and mean exercising MCAv in these individuals (p = 0.01). Older age was associated with lower exercising MCAv in the group not taking omega-3 supplements, while exercising MCAv showed no decline with increasing age in the group who reported omega-3 supplement use. These findings suggest omega-3 supplementation may have an important role in the preservation of CBF with aging.

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Self-Reported Omega-3 Supplement Use Moderates the Association between Age and Exercising Cerebral Blood Flow Velocity in Older Adults

10.20944/preprints202002.0323.v1 ◽

2020 ◽

Author(s):

Carolyn S. Kaufman ◽

Eric D. Vidoni ◽

Jeffrey M. Burns ◽

Mohammed R. Alwatban ◽

Sandra A. Billinger

Keyword(s):

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Blood Flow Velocity ◽

Multiple Linear Regression Model ◽

Transcranial Doppler Ultrasound ◽

Moderate Intensity ◽

Omega 3 ◽

Moderate Intensity Exercise ◽

Supplement Use

Cerebral blood flow (CBF) decreases across the lifespan, and chronic conditions such as dementia and stroke accelerate this decline. Impaired CBF results in reduced delivery of oxygen and nutrients, which can damage the brain over time. Thus, there is a need to identify lifestyle interventions including diet and exercise to maintain CBF with aging and in the presence of chronic disease. In the present study, we used transcranial Doppler ultrasound to record middle cerebral artery velocity (MCAv), a surrogate measure of CBF, during moderate-intensity exercise in sedentary, cognitively-normal older adults (N = 90). A multiple linear regression model (F(4, 85) = 3.21, p = 0.02) showed self-reported omega-3 supplement use significantly moderated the association between age and mean exercising MCAv in these individuals (p = 0.01). Older age was associated with lower exercising MCAv in the group not taking omega-3 supplements, while exercising MCAv showed no decline with increasing age in the group who reported omega-3 supplement use. These findings suggest omega-3 supplementation may have an important role in the preservation of CBF with aging.

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Regional Cerebral Blood Flow, Cerebral Blood Velocity, and Pulsatility Index in Newborn Dogs

Pediatric Research ◽

10.1203/00006450-198311000-00014 ◽

1983 ◽

Vol 17 (11) ◽

pp. 908-912 ◽

Cited By ~ 81

Author(s):

Daniel G Batton ◽

Jonathan Hellmann ◽

Milton J Hernandez ◽

M Jeffrey Maisels

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Pulsatility Index ◽

Regional Cerebral Blood Flow ◽

Blood Velocity ◽

Regional Cerebral Blood ◽

Cerebral Blood Velocity

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Comparison Between the Effects of Continuous and Intermittent Light-Intensity Aerobic Dance Exercise on Mood and Executive Functions in Older Adults

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.723243 ◽

2021 ◽

Vol 13 ◽

Author(s):

Kazuki Hyodo ◽

Kazuya Suwabe ◽

Daisuke Yamaguchi ◽

Hideaki Soya ◽

Takashi Arao

Keyword(s):

Older Adults ◽

Light Intensity ◽

Executive Functions ◽

Stroop Task ◽

Intermittent Exercise ◽

Moderate Intensity ◽

Older Individuals ◽

Moderate Intensity Exercise ◽

Intermittent Light ◽

Aerobic Dance

There is a growing body of evidence suggesting that one bout of moderate-intensity exercise enhances executive functions in older adults. However, in terms of safety, feasibility, and continuity, older individuals prefer light, easy, and fun exercises to moderate and stressful exercises for improving executive functions. Therefore, light-intensity aerobic dance exercise (LADE) could be suitable if it produces potential benefits related to executive functions. As for continuous vs. intermittent exercise, intermittent exercise has received a lot of attention, as it results in greater effects on mood and executive functions than continuous exercise; however, its effects in older adults remain uncertain. Thus, in this study, we aimed to examine the acute effects of intermittent LADE (I-LADE) in comparison with those of continuous LADE (C-LADE) on mood and executive functions. Fifteen healthy older adults participated in 10-min I-LADE and C-LADE conditions on separate days. Perceived enjoyment following exercise was assessed using the Physical Activity Enjoyment Scale (PACES). The pleasantness of the mood during exercise and pleasure and arousal levels after exercise were assessed using the Feeling Scale and Two-Dimensional Mood Scale, respectively. Executive function was assessed using the Stroop task before and after exercise. As a result, pleasantness of the mood during exercise and exercise enjoyment levels were greater in I-LADE than in C-LADE. Arousal and pleasure levels and Stroop task performance increased after both LADEs and did not differ between the two exercise conditions. These findings suggest that although enhancement of mood and executive functions after exercise did not differ between C-LADE and I-LADE, I-LADE could be more enjoyable and fun than C-LADE. This study will help in the development of exercise conditions that can enable the elderly to enhance their executive functions in a fun way.

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Regular walking breaks prevent the decline in cerebral blood flow associated with prolonged sitting

Journal of Applied Physiology ◽

10.1152/japplphysiol.00310.2018 ◽

2018 ◽

Vol 125 (3) ◽

pp. 790-798 ◽

Cited By ~ 31

Author(s):

Sophie E. Carter ◽

Richard Draijer ◽

Sophie M. Holder ◽

Louise Brown ◽

Dick H. J. Thijssen ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Carotid Artery ◽

Light Intensity ◽

Short Duration ◽

Sitting Time ◽

Peripheral Blood Flow ◽

Prolonged Sitting ◽

Increased Risk ◽

And Function

Decreased cerebrovascular blood flow and function are associated with lower cognitive functioning and increased risk of neurodegenerative diseases. Prolonged sitting impairs peripheral blood flow and function, but its effects on the cerebrovasculature are unknown. This study explored the effect of uninterrupted sitting and breaking up sitting time on cerebrovascular blood flow and function of healthy desk workers. Fifteen participants (10 male, 35.8 ± 10.2 yr, body mass index: 25.5 ± 3.2 kg/m2) completed, on separate days, three 4-h conditions in a randomized order: 1) uninterrupted sitting (SIT), 2) sitting with 2-min light-intensity walking breaks every 30 min (2WALK), or 3) sitting with 8-min light-intensity walking breaks every 2 h (8WALK). At baseline and 4 h, middle cerebral artery blood flow velocity (MCAv) and CO2 reactivity (CVR) of the MCA and carotid artery were measured using transcranial Doppler (TCD) and duplex ultrasound, respectively. Cerebral autoregulation (CA) was assessed with TCD using a squat-stand protocol and analyzed to generate values of gain and phase in the very low, low, and high frequencies. There was a significant decline in SIT MCAv (−3.2 ± 1.2 cm/s) compared with 2WALK (0.6 ± 1.5 cm/s, P = 0.02) but not between SIT and 8WALK (−1.2 ± 1.0 cm/s, P = 0.14). For CA, the change in 2WALK very low frequency phase (4.47 ± 4.07 degrees) was significantly greater than SIT (−3.38 ± 2.82 degrees, P = 0.02). There was no significant change in MCA or carotid artery CVR ( P > 0.05). Results indicate that prolonged uninterrupted sitting in healthy desk workers reduces cerebral blood flow; however, this is offset when frequent short-duration walking breaks are incorporated. NEW & NOTEWORTHY Prolonged uninterrupted sitting in healthy desk workers reduces cerebral blood flow. However, this reduction in cerebral blood flow is offset when frequent short-duration walking breaks are incorporated into this sitting period. For those who engage in long periods of sedentary behavior, chronically breaking up these sitting periods with frequent active break strategies may have important implications for cerebrovascular health; however, further research should explore this hypothesis.

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Sodium bicarbonate ingestion mitigates the heat-induced hyperventilation and reduction in cerebral blood velocity during exercise in the heat

Journal of Applied Physiology ◽

10.1152/japplphysiol.00261.2021 ◽

2021 ◽

Author(s):

Akira Katagiri ◽

Yasuhiko Kitadai ◽

Akira Miura ◽

Yoshiyuki Fukuba ◽

Naoto Fujii ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Sodium Bicarbonate ◽

Perceived Exertion ◽

Prolonged Exercise ◽

Minute Ventilation ◽

Blood Velocity ◽

Cerebral Hypoperfusion ◽

Main Effect ◽

Cerebral Blood Velocity

Hyperthermia during exercise in the heat causes minute ventilation (VE) to increase, which leads to reductions in arterial CO2 partial pressure (PaCO2) and cerebral blood flow. On the other hand, sodium bicarbonate ingestion reportedly results in metabolic alkalosis, leading to decreased and increased PaCO2 during prolonged exercise in a thermoneutral environment. Here, we investigated whether sodium bicarbonate ingestion suppresses heat-induced hyperventilation and the resultant hypocapnia and cerebral hypoperfusion during prolonged exercise in the heat. Eleven healthy men ingested a solution of sodium bicarbonate (0.3 g/kg body weight) (NaHCO3 trial) or sodium chloride (0.208 g/kg) (NaCl trial). Ninety minutes after the ingestion, the subjects performed a cycle exercise for 60 min at 50% of peak oxygen uptake in the heat (35°C and 40% relative humidity). Esophageal temperature did not differ between the trials throughout (P = 0.56, main effect of trial). VE gradually increased with exercise duration in the NaCl trial, but the increases in VE were attenuated in the NaHCO3 trial (P = 0.01, main effect of trial). Correspondingly, estimated PaCO2 and middle cerebral artery blood velocity (an index of anterior cerebral blood flow) were higher in the NaHCO3 than the NaCl trial (P = 0.002 and 0.04, main effects of trial). Ratings of perceived exertion were lower in the NaHCO3 than the NaCl trial (P = 0.02, main effect of trial). These results indicate that sodium bicarbonate ingestion mitigates heat-induced hyperventilation and reductions in PaCO2 and cerebral blood velocity during prolonged exercise in the heat.

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Aging reduces cerebral blood flow regulation following an acute hypertensive stimulus

Journal of Applied Physiology ◽

10.1152/japplphysiol.00137.2019 ◽

2020 ◽

Vol 128 (5) ◽

pp. 1186-1195

Author(s):

Alexander J. Rosenberg ◽

Elizabeth C. Schroeder ◽

Georgios Grigoriadis ◽

Sang Ouk Wee ◽

Kanokwan Bunsawat ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Flow Regulation ◽

Blood Velocity ◽

Elevated Blood ◽

Blood Flow Regulation ◽

Stimulus Effects ◽

Cerebral Blood Velocity ◽

Blood Pressure Responses ◽

The Brain

Reductions in cerebral blood flow and increases in flow pulsatility with aging are associated to cerebrovascular disease; however, little is known about how an acute hypertensive stimulus effects cerebral blood flow regulation in an aged population. Following the hypertensive stimulus, older adults elicit an attenuated increase in cerebral blood velocity and greater transmission of pulsatile velocity to the brain compared with young adults, demonstrating reduced cerebral blood flow regulation to elevated blood pressure responses with aging.

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Cerebral blood velocity and other cardiovascular responses to 2 days of head-down tilt

Journal of Applied Physiology ◽

10.1152/jappl.1993.74.1.319 ◽

1993 ◽

Vol 74 (1) ◽

pp. 319-325 ◽

Cited By ~ 41

Author(s):

M. A. Frey ◽

T. H. Mader ◽

J. P. Bagian ◽

J. B. Charles ◽

R. T. Meehan

Keyword(s):

Heart Rate ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Peripheral Resistance ◽

Systolic Arterial Pressure ◽

Cardiovascular Responses ◽

Blood Velocity ◽

Cerebral Blood Velocity ◽

Blood Flow Velocities ◽

Flow Velocities

Spaceflight induces a cephalad redistribution of fluid volume and blood flow within the human body, and space motion sickness, which is a problem during the first few days of spaceflight, could be related to these changes in fluid status and in blood flow of the cerebrum and vestibular system. To evaluate possible changes in cerebral blood flow during simulated weightlessness, we measured blood velocity in the middle cerebral artery (MCA) along with retinal vascular diameters, intraocular pressure, impedance cardiography, and sphygmomanometry on nine men (26.2 +/- 6.6 yr) morning and evening for 2 days during continuous 10 degrees head-down tilt (HDT). When subjects went from seated to head-down bed rest, their heart rate and retinal diameters decreased, and intraocular pressures increased. After 48 h of HDT, blood flow velocity in the MCA was decreased and thoracic impedance was increased, indicating less fluid in the thorax. Percent changes in blood flow velocities in the MCA after 48 h of HDT were inversely correlated with percent changes in retinal vascular diameters. Blood flow velocities in the MCA were inversely correlated (intersubject) with arterial pressures and retinal vascular diameters. Heart rate, stroke volume, cardiac output, systolic arterial pressure, and at times pulse pressure and blood flow velocities in the MCA were greater in the evening. Total peripheral resistance was higher in the morning. Although cerebral blood velocity is reduced after subjects are head down for 2 days, the inverse relationship with retinal vessel diameters, which have control analogous to that of cerebral vessels, indicates cerebral blood flow is not reduced.

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Doppler-Pulsatility Index

PEDIATRICS ◽

10.1542/peds.71.2.298 ◽

1983 ◽

Vol 71 (2) ◽

pp. 298-299

Author(s):

DANIEL G. BATTON ◽

JONATHAN HELLMANN ◽

M. JEFFREY MAISELS

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Doppler Effect ◽

Pulsatility Index ◽

Blood Velocity ◽

Cerebral Blood Velocity ◽

Considerable Controversy ◽

The Doppler Effect ◽

Cerebral Vascular Resistance

To the Editor.— The determination of cerebral blood velocity in the newborn infant using transfontanel Doppler ultrasound has been discussed in detail in two recent commentaries.1,2 Whereas the use of the Doppler effect to determine blood velocity is well accepted, it is apparent that considerable controversy exists regarding the ability of this technique to measure cerebral blood flow in the neonate.1,2 In particular, the hemodynamic significance of the pulsatility index (PI) remains unclear. It has been suggested that the PI reflects cerebral vascular resistance based on the assumption that, as resistance is altered, primarily diastolic, and not systolic, blood velocity will change.

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