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Paiva Prudente T, Oliva HNP, Oliva IO, Mezaiko E, Monteiro-Junior RS. Effects of Physical Exercise on Cerebral Blood Velocity in Older Adults: A Systematic Review and Meta-Analysis. Behav Sci (Basel) 2023; 13:847. [PMID: 37887497 PMCID: PMC10604216 DOI: 10.3390/bs13100847] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/10/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
As the older population grows, there is an increasing interest in understanding how physical exercise can counteract the changes seen with aging. The benefits of exercise to general health, and especially to the cardiovascular system, have been a topic of discussion for decades. However, there is still a need to elucidate the effects of training programs on the cerebrovascular blood velocity in older people. This systematic review and meta-analysis aimed to investigate the effect of physical exercise on the cerebral blood velocity in older people (PROSPERO CRD42019136305). A search was performed on PubMed, Web of Science, EBSCO, ScienceDirect, and Scopus from the inception of this study to October 2023, retrieving 493 results, of which 26 were included, analyzing more than 1000 participants. An overall moderate risk of bias was found for the studies using the Cochrane risk-of-bias tools for randomized and non-randomized clinical trials. The pooled results of randomized trials showed that older people who underwent physical exercise presented a statistically significant increase in cerebral blood velocity (3.58; 95%CI = 0.51, 6.65; p = 0.02). This result indicates that physical exercise is important to help maintain cerebral health in older adults.
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Affiliation(s)
- Tiago Paiva Prudente
- School of Medicine, Universidade Federal de Goiás, Goiânia 74690-900, GO, Brazil;
| | - Henrique Nunes Pereira Oliva
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, USA;
- Postgraduation Programme of Health Sciences, Universidade Estadual de Montes Claros, Montes Claros 39401-089, MG, Brazil
| | - Isabela Oliveira Oliva
- School of Medicine, Centro Universitario FIPMoc (UNIFIPMoc), Montes Claros 39408-007, MG, Brazil;
| | - Eleazar Mezaiko
- School of Dentistry, Universidade Federal de Goiás, Goiânia 74690-900, GO, Brazil;
| | - Renato Sobral Monteiro-Junior
- Postgraduation Programme of Health Sciences, Universidade Estadual de Montes Claros, Montes Claros 39401-089, MG, Brazil
- Postgraduation Programme of Neurology/Neuroscience, Universidade Federal, Niterói 24020-141, RJ, Brazil
- Research and Study Group in Neuroscience, Exercise, Health and Sport—GENESEs, Physical Education Department, Universidade Estadual de Montes Claros, Montes Claros 39401-089, MG, Brazil
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Miutz LN, Burma JS, Van Roessel RK, Johnson NE, Phillips AA, Emery CA, Brassard P, Smirl JD. The effect of supine cycling and progressive lower body negative pressure on cerebral blood velocity responses. J Appl Physiol (1985) 2023; 135:316-325. [PMID: 37348016 DOI: 10.1152/japplphysiol.00758.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 06/08/2023] [Accepted: 06/08/2023] [Indexed: 06/24/2023] Open
Abstract
Moderate-intensity aerobic exercise increases cerebral blood velocity (CBv) primarily due to hyperpnea-induced vasodilation; however, the integrative control of cerebral blood flow (CBF) allows other factors to contribute to the vasodilation. Although lower body negative pressure (LBNP) can reduce CBv, the exact LBNP intensity required to blunt the aforementioned exercise-induced CBv response is unknown. This could hold utility for concussion recovery, allowing individuals to exercise at higher intensities without symptom exacerbation. Thirty-two healthy adults (age: 20-33 yr; 19 females/13 males) completed a stepwise maximal exercise test during a first visit to determine each participant's wattage associated with their exercise-induced maximal CBv increase. During the second visit, following supine rest, participants completed moderate-intensity exercise at their determined threshold, while progressive LBNP was applied at 0, -20, -40, -60, -70, -80, and ∼88 Torr. Bilateral middle cerebral artery blood velocities (MCAvs), mean arterial pressure (MAP), heart rate, respiratory rate, and end-tidal carbon dioxide levels were measured continuously. Two-way analysis of variance with effect sizes compared between sexes and stages. Compared with resting supine baseline, averaged MCAv was elevated during 0 and -20 Torr LBNP (q value > 7.73; P < 0.001); however, no differences were noted between baseline and -40 to -70 Torr (q value < |4.24|; P > 0.262). Differences were present between females and males for absolute MCAv measures (q value > 11.2; P < 0.001), but not when normalized to baseline (q value < 0.03; P > 0.951). Supine cycling-elicited increases in MCAv are able to be blunted during the application of LBNP ranging from -40 to -70 Torr. The blunted CBv response demonstrates the potential benefit of allowing individuals to aerobically train (moderate-intensity supine cycling with LBNP) without exacerbating symptoms during the concussion recovery phase.NEW & NOTEWORTHY The current investigation demonstrated that moderate-intensity supine cycling-induced increases in cerebral blood velocities were balanced by the lower body negative pressure-induced decreases in cerebral blood velocity. Although performed in a healthy population, the results may lend themselves to a potential treatment option for individuals recovering from concussion or experience persistent concussion symptoms.
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Affiliation(s)
- Lauren N Miutz
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Department of Health and Sport Science, University of Dayton, Dayton, Ohio, United States
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Rowan K Van Roessel
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Nathan E Johnson
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Aaron A Phillips
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Departments of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, University of Calgary, Calgary, Alberta, Canada
- Biomedical Engineering, and Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Carolyn A Emery
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, University Laval, Quebec City, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec City, Québec, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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Kawasaki A, Hayashi N. Playing a musical instrument increases blood flow in the middle cerebral artery. PLoS One 2022; 17:e0269679. [PMID: 35675278 PMCID: PMC9176837 DOI: 10.1371/journal.pone.0269679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 05/25/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose Studies using functional magnetic resonance imaging and positron-emission tomography suggest that many regions of the brain are activated by such complex muscle activity. Although these studies demonstrated relative increases in blood flow in some brain regions with increased neural activity, whether or not the absolute value of cerebral blood flow increases has yet to be elucidated. It also remains unknown whether playing musical instruments affects cerebral blood flow. The aim of this study was to determine the impact of playing a musical instrument on blood flow velocity in the middle cerebral artery (MCAv) by using Doppler ultrasound to measure absolute values of arterial flow velocity. Methods Thirteen musicians performed three pieces of music with different levels of difficulty: play for the first time (FS), music in practice (PR) and already mastered (MS) on either piano or violin. MCAv was recorded continuously from 10 min before until 10 min after playing. Associations between the cerebral blood flow response and blood pressure and gas-exchange variables were examined. Results PR and MS significantly increased the MCAv. The blood pressure increased significantly in performances of all difficulty levels except for MS. There were no significant changes in exhaled gas variables during the performance. Conclusion These findings suggest that playing a musical instrument increases MCAv, and that this change is influenced by the difficulty of the performance.
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Affiliation(s)
- Ai Kawasaki
- Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | - Naoyuki Hayashi
- Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan.,Faculty of Sport Sciences, Waseda University, Saitama, Japan
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Khachidze I, Gugushvili M, Advadze M. EEG Characteristics to Hyperventilation by Age and Sex in Patients With Various Neurological Disorders. Front Neurol 2021; 12:727297. [PMID: 34630301 PMCID: PMC8493288 DOI: 10.3389/fneur.2021.727297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/23/2021] [Indexed: 11/17/2022] Open
Abstract
Introduction: Hyperventilation provocation test(s) (HPT) concomitant to electroencephalography (EEG) may detect hidden disorders of the nervous system (CNS). There are various types of abnormal EEG in responses to HPT that provoke different interpretations. However, it is not evident how the onset time of pathological EEG responses to hyperventilation (PERH) reveals dysfunction of the CNS in humans. It is also not clear if age and biological sex affect EEG characteristics in response to HPT. Our previous studies have revealed three types of PERH (disorganization of basic rhythm, paroxysmal discharges, epileptiform activity) concerning the manifestation time of first, second, and third minutes. The current work aims to classify the PERH with regards to age (3–6, 7–12, 13–18, 19–30, 31–50, 50 > year) and the biological sex of the patients. Methods: This study examined the EEG of 985 outpatients with various functional disorders of the CNS. The patients were assigned to one of three experimental groups based on the time occurrence of PERH in response to the HPT. Results: The disorganized basic EEG rhythm in the first, second, third minute of HPT was observed across all age and sex groups. All three types of PERH in the first minute were comparable for both sexes. However, some discrepancies between females compared to males were observed in the second and third minutes. All three types of PERH in the first and the second minutes were found only in women. The second type of PERH has revealed at the second minute of PHT in 13–18-year-old five girls. Conclusion: The three main types of PERH were detected at the first minute in all age groups and sex in patients with various CNS dysfunctions. It is diagnostically informative should be used as a marker during the monitoring of treatment. The specific activity of the brain's response to HPT depends on time, age, sex. The data indicate that taking into account sex differences and age during HPT leads to better results. The sensitivity and severity of the NS reaction toward hypocapnia, stress, and emotion increase in women. Therefore, in such cases should not be recommended to expand functional loads.
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Affiliation(s)
- Irma Khachidze
- Department of Human Psychophysiology, I. Beritashvili Centre of Experimental Biomedicine. Tbilisi, Georgia.,Faculty of Medicine, Georgian National University SEU, Tbilisi, Georgia
| | - Manana Gugushvili
- Department of Human Psychophysiology, I. Beritashvili Centre of Experimental Biomedicine. Tbilisi, Georgia
| | - Maia Advadze
- Faculty of Medicine, Georgian National University SEU, Tbilisi, Georgia
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5
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Weston ME, Barker AR, Tomlinson OW, Coombes JS, Bailey TG, Bond B. Differences in cerebrovascular regulation and ventilatory responses during ramp incremental cycling in children, adolescents, and adults. J Appl Physiol (1985) 2021; 131:1200-1210. [PMID: 34435503 DOI: 10.1152/japplphysiol.00182.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Regulation of cerebral blood flow during exercise in youth is poorly understood. This study investigated the cerebrovascular and ventilatory responses to a ramp incremental cycle test to exhaustion in 14 children (means ± SD age: 9.4 ± 0.9 yr), 14 adolescents (12.4 ± 0.4 yr), and 19 adults (23.4 ± 2.5 yr). Middle cerebral artery blood velocity (MCAv), partial pressure of end-tidal CO2 ([Formula: see text]), and ventilatory parameters were analyzed at baseline, gas exchange threshold (GET), respiratory compensation point (RCP), and exhaustion. The increase in minute ventilation relative to CO2 production during exercise was also calculated (V̇e/V̇co2 slope). Relative change from baseline (Δ%) in MCAv was lower in children, compared with adolescents and adults at GET [15 ± 10% vs. 26 ± 14%, and 24 ± 10%, respectively, P ≤ 0.03, effect size (d) = 0.9] and RCP (13 ± 11% vs. 24 ± 16% and 27 ± 15%, respectively, P ≤ 0.05, d ≥ 0.8). Δ%MCAv was similar in adults and adolescents at all intensities and similar in all groups at exhaustion. The magnitude of the V̇E/V̇co2 slope was negatively associated with Δ%MCAv at GET and RCP across all participants (P ≤ 0.01, r = -0.37 to -0.48). Δ%[Formula: see text] was smaller in children and adolescents compared with adults at GET and RCP (P ≤ 0.05, d ≥ 0.6). In children, Δ%[Formula: see text] and Δ%MCAv were not associated from baseline-GET (r¯ = 0.14) and were moderately associated from RCP-exhaustion (r¯ = 0.49). These relationships strengthened with increasing age and were stronger in adolescents (baseline-GET: r¯ = 0.47, RCP-exhaustion: r¯ = 0.62) and adults (baseline-GET: r¯ = 0.66, RCP-exhaustion: r¯ = 0.78). These findings provide the first evidence on the development of the regulatory role of [Formula: see text] on MCAv during exercise in children, adolescents, and adults.NEW & NOTEWORTHY This is the first study to observe similar increases in cerebral blood flow during incremental exercise in adolescents and adults. Increases in cerebral blood flow during exercise were smaller in children compared with adolescents and adults and were associated with a greater V̇E/V̇co2 slope. This study also provides the first evidence on the progressive development of the regulatory role of end-tidal CO2 on cerebral blood flow during exercise during the transition from childhood to adulthood.
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Affiliation(s)
- Max E Weston
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom.,Physiology and Ultrasound Laboratory in Science and Exercise, School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Alan R Barker
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Owen W Tomlinson
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Jeff S Coombes
- Physiology and Ultrasound Laboratory in Science and Exercise, School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Tom G Bailey
- Physiology and Ultrasound Laboratory in Science and Exercise, School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Bert Bond
- Children's Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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Burma JS, Macaulay A, Copeland P, Khatra O, Bouliane KJ, Smirl JD. Comparison of cerebrovascular reactivity recovery following high-intensity interval training and moderate-intensity continuous training. Physiol Rep 2021; 8:e14467. [PMID: 32506845 PMCID: PMC7276190 DOI: 10.14814/phy2.14467] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 04/21/2020] [Accepted: 04/25/2020] [Indexed: 12/27/2022] Open
Abstract
A common inclusion criterion when assessing cerebrovascular (CVR) metrics is for individuals to abstain from exercise for 12–24 hr prior to data collections. While several studies have examined CVR during exercise, the literature describing CVR throughout post‐exercise recovery is sparse. The current investigation examined CVR measurements in nine participants (seven male) before and for 8 hr following three conditions: 45‐min moderate‐continuous exercise (at ~50% heart‐rate reserve), 25‐min high‐intensity intervals (ten, one‐minute intervals at ~85% heart‐rate reserve), and a control day (30‐min quiet rest). The hypercapnic (40–60 mmHg) and hypocapnic (25–40 mmHg) slopes were assessed via a modified rebreathing technique and controlled stepwise hyperventilation, respectively. All testing was initiated at 8:00a.m. with transcranial Doppler ultrasound measurements to index cerebral blood velocity performed prior to the condition (pre) with serial follow‐ups at zero, one, two, four, six, and eight hours within the middle and posterior cerebral artery (MCA, PCA). Absolute and relative MCA and PCA hypercapnic slopes were attenuated following high‐intensity intervals at hours zero and one (all p < .02). No alterations were observed in either hypocapnic or hypercapnic slopes following the control or moderate‐continuous exercise (all p > .13), aside from a reduced relative hypercapnic MCA slope at hours zero and one following moderate‐continuous exercise (all p < .005). The current findings indicate the common inclusion criteria of a 12–24 hr time restriction on exercise can be reduced to two hours when performing CVR measures. Furthermore, the consistent nature of the CVR indices throughout the control day indicate reproducible testing sessions can be made between 8:00a.m. and 7:00p.m.
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Affiliation(s)
- Joel S Burma
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, University of Calgary, Calgary, AB, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Alannah Macaulay
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Paige Copeland
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Kevin J Bouliane
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Jonathan D Smirl
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, University of Calgary, Calgary, AB, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute, University of Calgary, Calgary, AB, Canada
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Burma JS, Copeland P, Macaulay A, Khatra O, Wright AD, Smirl JD. Dynamic cerebral autoregulation across the cardiac cycle during 8 hr of recovery from acute exercise. Physiol Rep 2021; 8:e14367. [PMID: 32163235 PMCID: PMC7066871 DOI: 10.14814/phy2.14367] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 12/28/2019] [Accepted: 12/30/2019] [Indexed: 01/02/2023] Open
Abstract
Current protocols examining cerebral autoregulation (CA) parameters require participants to refrain from exercise for 12–24 hr, however there is sparse objective evidence examining the recovery trajectory of these measures following exercise across the cardiac cycle (diastole, mean, and systole). Therefore, this study sought to determine the duration acute exercise impacts CA and the within‐day reproducibility of these measures. Nine participants performed squat–stand maneuvers at 0.05 and 0.10 Hz at baseline before three interventions: 45‐min moderate‐continuous exercise (at 50% heart‐rate reserve), 30‐min high‐intensity intervals (ten, 1‐min at 85% heart‐rate reserve), and a control day (30‐min quiet rest). Squat–stands were repeated at hours zero, one, two, four, six, and eight after each condition. Transcranial doppler ultrasound of the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was used to characterize CA parameters across the cardiac cycle. At baseline, the systolic CA parameters were different than mean and diastolic components (ps < 0.015), however following both exercise protocols in both frequencies this disappeared until hour four within the MCA (ps > 0.079). In the PCA, phase values were affected only following high‐intensity intervals until hour four (ps > 0.055). Normalized gain in all cardiac cycle domains remained different following both exercise protocols (ps < 0.005) and across the control day (p < .050). All systolic differences returned by hour six across all measures (ps < 0.034). Future CA studies may use squat–stand maneuvers to assess the cerebral pressure–flow relationship 6 hr after exercise. Finally, CA measures under this paradigm appear to have negligible within‐day variation, allowing for reproducible interpretations to be drawn.
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Affiliation(s)
- Joel S Burma
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Center, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Paige Copeland
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Alannah Macaulay
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Alexander D Wright
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,MD/PhD Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,Southern Medical Program, University of British Columbia, Kelowna, BC, Canada
| | - Jonathan D Smirl
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Center, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Southern Medical Program, University of British Columbia, Kelowna, BC, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
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Burma JS, Macaulay A, Copeland PV, Khatra O, Bouliane KJ, Smirl JD. Temporal evolution of neurovascular coupling recovery following moderate- and high-intensity exercise. Physiol Rep 2021; 9:e14695. [PMID: 33463899 PMCID: PMC7814491 DOI: 10.14814/phy2.14695] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Studies examining neurovascular coupling (NVC) require participants to refrain from exercise for 12-24 hours. However, there is a paucity of empirical evidence for this restriction. The objectives for this study were to delineate the time-course recovery of NVC metrics following exercise and establish the NVC within- and between-day reliability. METHODS Nine participants completed a complex visual search paradigm to assess NVC via transcranial Doppler ultrasound of the posterior cerebral artery blood velocity (PCA). Measurements were performed prior to and throughout the 8-hour recovery period following three randomized conditions: 45 minutes of moderate-intensity exercise (at 50% heart-rate reserve), 30 minutes high-intensity intervals (10, 1-minute intervals at 85% heart-rate reserve), and control (30 minutes quiet rest). In each condition, baseline measures were collected at 8:00am with serial follow-ups at hours zero, one, two, four, six, and eight. RESULTS Area-under-the-curve and time-to-peak PCA velocity during the visual search were attenuated at hour zero following high-intensity intervals (all p < 0.05); however, these NVC metrics recovered at hour one (all p > 0.13). Conversely, baseline PCA velocity, peak PCA velocity, and the relative percent increase were not different following high-intensity intervals compared to baseline (all p > 0.26). No NVC metrics differed from baseline following both moderate exercise and control conditions (all p > 0.24). The majority of the NVC parameters demonstrated high levels of reliability (intraclass correlation coefficient: >0.90). CONCLUSION Future NVC assessments can take place a minimum of one hour following exercise. Moreover, all metrics did not change across the control condition, therefore future studies using this methodology can reliably quantify NVC between 8:00am and 7:00 pm.
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Affiliation(s)
- Joel S. Burma
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryABCanada
| | - Alannah Macaulay
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- School of Health Sciences, Nuclear MedicineBritish Columbia Institute of TechnologyBurnabyBCCanada
| | - Paige V. Copeland
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Omeet Khatra
- Faculty of MedicineUniversity of British ColumbiaVancouverBCCanada
| | - Kevin J. Bouliane
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Jonathan D. Smirl
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryABCanada
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9
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The Effect of Stroke on Middle Cerebral Artery Blood Flow Velocity Dynamics During Exercise. J Neurol Phys Ther 2020; 43:212-219. [PMID: 31449179 PMCID: PMC6744289 DOI: 10.1097/npt.0000000000000289] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND PURPOSE Previous work demonstrates that older adults have a lower response in the middle cerebral artery velocity (MCAv) to an acute bout of moderate-intensity exercise when compared with young adults. However, no information exists regarding MCAv response to exercise after stroke. We tested whether MCAv response to an acute bout of moderate-intensity exercise differed between participants 3 months after stroke and an age- and sex-matched control group of older adults (CON). A secondary objective was to compare MCAv response between the stroke- and non-stroke-affected MCAv. METHODS Using transcranial Doppler ultrasound, we recorded MCAv during a 90-second baseline (BL) followed by a 6-minute moderate-intensity exercise bout using a recumbent stepper. Heart rate (HR), end-tidal CO2 (PETCO2), and beat-to-beat mean arterial blood pressure (MAP) were additional variables of interest. The MCAv response measures included BL, peak response amplitude (Amp), time delay (TD), and time constant (τ). RESULTS The Amp was significantly lower in the stroke-affected MCAv compared with CON (P < 0.01) and in the nonaffected MCAv compared with CON (P = 0.03). No between-group differences were found between TD and τ. No significant differences were found during exercise for PETCO2 and MAP while HR was lower in participants with stroke (P < 0.01). Within the group of participants with stroke, no differences were found between the stroke-affected and non-stroke-affected sides for any measures. DISCUSSION AND CONCLUSIONS Resolution of the dynamic response profile has the potential to increase our understanding of the cerebrovascular control mechanisms and test cerebrovascular response to physical therapy-driven interventions such as exercise.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A284).
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Klein T, Bailey TG, Wollseiffen P, Schneider S, Askew CD. The effect of age on cerebral blood flow responses during repeated and sustained stand to sit transitions. Physiol Rep 2020; 8:e14421. [PMID: 32378357 PMCID: PMC7202987 DOI: 10.14814/phy2.14421] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 03/20/2020] [Accepted: 03/21/2020] [Indexed: 12/02/2022] Open
Abstract
INTRODUCTION Aging is associated with impaired cerebrovascular blood flow and function, attributed to reduced vasodilatory capacity of the cerebrovascular network. Older adults may also have an impaired relationship between changes in blood pressure and cerebral blood flow; however, previous reports conflict. This study aimed to compare the blood pressure and cerebral blood flow responses to both repeated and sustained stand-to-sit transitions in young and older adults, and to assess the relationship with cerebrovascular reactivity. METHODS In 20 young (age: 24 ± 4 years) and 20 older (age: 71 ± 7 years) adults we compared middle cerebral artery flow velocity (MCAv), end-tidal partial pressure of carbon dioxide (PET CO2 ), and blood pressure (mean arterial blood pressure [MAP]) during repeated stand-to-sit (10 s standing and 10 s sitting) and sustained stand-to-sit (3 min standing followed by 2 min sitting) transitions. Cerebrovascular reactivity to changes in carbon dioxide levels was assessed using a repeated breath-hold test. RESULTS The % change in MCAv per % change in MAP (%∆MCAv/%∆MAP) was higher in the older adults than in the young adults during repeated stand-to-sit transitions. During the sustained protocol the %∆MCAv/%∆MAP response was similar in both age groups. A high %∆MCAv/%∆MAP response during the repeated stand-to-sit protocol was associated with low cerebrovascular reactivity to CO2 (r = -.39; p < .01), which was significantly lower in the older adults. CONCLUSION These findings suggest that the higher %∆MCAv/%∆MAP during repeated stand-sit transitions was associated with impaired cerebrovascular reactivity. Impairments in endothelial function and vascular stiffness with age may contribute to the altered transient cerebral pressure-flow responses in older adults.
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Affiliation(s)
- Timo Klein
- VasoActive Research GroupSchool of Health and Sport SciencesUniversity of the Sunshine CoastMaroochydore DCQLDAustralia
- Institute of Movement and NeuroscienceGerman Sport University CologneCologneGermany
| | - Tom G. Bailey
- VasoActive Research GroupSchool of Health and Sport SciencesUniversity of the Sunshine CoastMaroochydore DCQLDAustralia
- Centre for Research on ExercisePhysical Activity and HealthSchool of Human Movement and Nutrition SciencesThe University of QueenslandBrisbaneQLDAustralia
| | - Petra Wollseiffen
- Institute of Movement and NeuroscienceGerman Sport University CologneCologneGermany
| | - Stefan Schneider
- VasoActive Research GroupSchool of Health and Sport SciencesUniversity of the Sunshine CoastMaroochydore DCQLDAustralia
- Institute of Movement and NeuroscienceGerman Sport University CologneCologneGermany
| | - Christopher D. Askew
- VasoActive Research GroupSchool of Health and Sport SciencesUniversity of the Sunshine CoastMaroochydore DCQLDAustralia
- Sunshine Coast Health InstituteSunshine Coast Hospital and Health ServiceBirtinyaQLDAustralia
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11
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Steventon JJ, Hansen AB, Whittaker JR, Wildfong KW, Nowak-Flück D, Tymko MM, Murphy K, Ainslie PN. Cerebrovascular Function in the Large Arteries Is Maintained Following Moderate Intensity Exercise. Front Physiol 2018; 9:1657. [PMID: 30519192 PMCID: PMC6258791 DOI: 10.3389/fphys.2018.01657] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 11/02/2018] [Indexed: 01/13/2023] Open
Abstract
Exercise has been shown to induce cerebrovascular adaptations. However, the underlying temporal dynamics are poorly understood, and regional variation in the vascular response to exercise has been observed in the large cerebral arteries. Here, we sought to measure the cerebrovascular effects of a single 20-min session of moderate-intensity exercise in the one hour period immediately following exercise cessation. We employed transcranial Doppler (TCD) ultrasonography to measure cerebral blood flow velocity (CBFV) in the middle cerebral artery (MCAv) and posterior cerebral artery (PCAv) before, during, and following exercise. Additionally, we simultaneously measured cerebral blood flow (CBF) in the internal carotid artery (ICA) and vertebral artery (VA) before and up to one hour following exercise cessation using Duplex ultrasound. A hypercapnia challenge was used before and after exercise to examine exercise-induced changes in cerebrovascular reactivity (CVR). We found that MCAv and PCAv were significantly elevated during exercise (p = 4.81 × 10-5 and 2.40 × 10-4, respectively). A general linear model revealed that these changes were largely explained by the partial pressure of end-tidal CO2 and not a direct vascular effect of exercise. After exercise cessation, there was no effect of exercise on CBFV or CVR in the intracranial or extracranial arteries (all p > 0.05). Taken together, these data confirm that CBF is rapidly and uniformly regulated following exercise cessation in healthy young males.
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Affiliation(s)
- Jessica J Steventon
- Neuroscience and Mental Health Research Institute, School of Medicine, Cardiff University, Cardiff, United Kingdom.,Cardiff University Brain Research Imaging Centre, School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom
| | - Alex B Hansen
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Science, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Joseph R Whittaker
- Cardiff University Brain Research Imaging Centre, School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom
| | - Kevin W Wildfong
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Science, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Daniela Nowak-Flück
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Science, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Michael M Tymko
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Science, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Kevin Murphy
- Cardiff University Brain Research Imaging Centre, School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom
| | - Phil N Ainslie
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Science, University of British Columbia Okanagan, Kelowna, BC, Canada
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12
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Ward JL, Craig JC, Liu Y, Vidoni ED, Maletsky R, Poole DC, Billinger SA. Effect of healthy aging and sex on middle cerebral artery blood velocity dynamics during moderate-intensity exercise. Am J Physiol Heart Circ Physiol 2018; 315:H492-H501. [PMID: 29775407 PMCID: PMC6172645 DOI: 10.1152/ajpheart.00129.2018] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Blood velocity measured in the middle cerebral artery (MCAV) increases with finite kinetics during moderate-intensity exercise, and the amplitude and dynamics of the response provide invaluable insights into the controlling mechanisms. The MCAV response after exercise onset is well fit to an exponential model in young individuals but remains to be characterized in their older counterparts. The responsiveness of vasomotor control degrades with advancing age, especially in skeletal muscle. We tested the hypothesis that older subjects would evince a slower and reduced MCAV response to exercise. Twenty-nine healthy young (25 ± 1 yr old) and older (69 ± 1 yr old) adults each performed a rapid transition from rest to moderate-intensity exercise on a recumbent stepper. Resting MCAV was lower in older than young subjects (47 ± 2 vs. 64 ± 3 cm/s, P < 0.001), and amplitude from rest to steady-state exercise was lower in older than young subjects (12 ± 2 vs. 18 ± 3 cm/s, P = 0.04), even after subjects were matched for work rate. As hypothesized, the time constant was significantly longer (slower) in the older than young subjects (51 ± 10 vs. 31 ± 4 s, P = 0.03), driven primarily by older women. Neither age-related differences in fitness, end-tidal CO2, nor blood pressure could account for this effect. Thus, MCAV kinetic analyses revealed a marked impairment in the cerebrovascular response to exercise in older individuals. Kinetic analysis offers a novel approach to evaluate the efficacy of therapeutic interventions for improving cerebrovascular function in elderly and patient populations. NEW & NOTEWORTHY Understanding the dynamic cerebrovascular response to exercise has provided insights into sex-related cerebrovascular control mechanisms throughout the aging process. We report novel differences in the kinetics response of cerebrovascular blood velocity after the onset of moderate-intensity exercise. The exponential increase in brain blood flow from rest to exercise revealed that 1) the kinetics profile of the older group was blunted compared with their young counterparts and 2) the older women demonstrated a slowed response.
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Affiliation(s)
- Jaimie L Ward
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center , Kansas City, Kansas
| | - Jesse C Craig
- Department of Kinesiology and Department of Anatomy and Physiology, Kansas State University , Manhattan, Kansas
| | - Yumei Liu
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center , Kansas City, Kansas
| | - Eric D Vidoni
- University of Kansas Alzheimer's Disease Center, Fairway, Kansas
| | | | - David C Poole
- Department of Kinesiology and Department of Anatomy and Physiology, Kansas State University , Manhattan, Kansas
| | - Sandra A Billinger
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center , Kansas City, Kansas
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13
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Evaluating the methods used for measuring cerebral blood flow at rest and during exercise in humans. Eur J Appl Physiol 2018; 118:1527-1538. [DOI: 10.1007/s00421-018-3887-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 05/09/2018] [Indexed: 10/16/2022]
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14
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Andrianopoulos V, Vogiatzis I, Gloeckl R, Bals R, Koczulla RA, Kenn K. Cerebral oxygen availability during exercise in COPD patients with cognitive impairment. Respir Physiol Neurobiol 2018; 254:64-72. [PMID: 29729396 DOI: 10.1016/j.resp.2018.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/30/2018] [Accepted: 05/01/2018] [Indexed: 02/07/2023]
Abstract
Insufficient cerebral blood flow regulation to meet increasing metabolic demand during physical exertion could be associated with cognitive impairment. We compared cerebral oxygen availability during exercise in cognitively impaired (CI) to cognitively normal (CN) COPD patients. Fifty-two patients (FEV1: 51 ± 16%) were classified as CN or CI according to the Montreal Cognitive Assessment. Patients performed cycle-ergometry at 75% peak capacity with continuous measurement of Near-Infrared Spectroscopy frontal-cortex Tissue oxygen Saturation Index (TSI), cerebral haemoglobin indices (oxy/deoxy/total- Hb), transcutaneous carbon-dioxide partial pressure (TcPCO2), and arterial oxygen saturation (SpO2). Twenty-one patients (40%) presented evidences of CI. During exercise, CN and CI patients exhibited mild to moderate SpO2decline (nadir[Δ]≥ -3 ± 2% and -5 ± 3%, respectively) but preserved baseline frontal-cortex TSI levels, whilst presenting small TcPCO2 perturbations and increased cerebral total-Hb (post [Δ]≥ 2.0 ± 3 μM sec-1). CI patients preserve the capacity to adequately maintain cerebral oxygen availability during submaximal exercise. Therefore, rehabilitative exercise training in CI patients with COPD exhibiting mild to moderate exercise-induced SpO2 decline does not appear to lead to reduced cerebral oxygen availability.
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Affiliation(s)
- Vasileios Andrianopoulos
- Institute for Pulmonary Rehabilitation Research, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany.
| | - Ioannis Vogiatzis
- Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University Newcastle, United Kingdom; Faculty of Physical Education and Sports Sciences, National and Kapodistrian University of Athens, Greece.
| | - Rainer Gloeckl
- Department of Respiratory Medicine & Exercise Therapy, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department for Prevention and Sports Medicine, Klinikum Rechts der Isar, Technical University Munich (TUM), Munich, Germany.
| | - Robert Bals
- Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany.
| | - Rembert A Koczulla
- Department of Respiratory Medicine & Exercise Therapy, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department of Pulmonary Rehabilitation, Philipps University Marburg, Marburg, Germany; German Center of Lung Research (DZL), Giessen-Marburg, Germany.
| | - Klaus Kenn
- Department of Respiratory Medicine & Exercise Therapy, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department of Pulmonary Rehabilitation, Philipps University Marburg, Marburg, Germany; German Center of Lung Research (DZL), Giessen-Marburg, Germany.
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15
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Smith KJ, Ainslie PN. Regulation of cerebral blood flow and metabolism during exercise. Exp Physiol 2017; 102:1356-1371. [PMID: 28786150 DOI: 10.1113/ep086249] [Citation(s) in RCA: 188] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 07/31/2017] [Indexed: 12/18/2022]
Abstract
NEW FINDINGS What is the topic of this review? The manuscript collectively combines the experimental observations from >100 publications focusing on the regulation of cerebral blood flow and metabolism during exercise from 1945 to the present day. What advances does it highlight? This article highlights the importance of traditional and historical assessments of cerebral blood flow and metabolism during exercise, as well as traditional and new insights into the complex factors involved in the integrative regulation of brain blood flow and metabolism during exercise. The overarching theme is the importance of quantifying cerebral blood flow and metabolism during exercise using techniques that consider multiple volumetric cerebral haemodynamics (i.e. velocity, diameter, shear and flow). Cerebral function in humans is crucially dependent upon continuous oxygen delivery, metabolic nutrients and active regulation of cerebral blood flow (CBF). As a consequence, cerebrovascular function is precisely titrated by multiple physiological mechanisms, characterized by complex integration, synergism and protective redundancy. At rest, adequate CBF is regulated through reflexive responses in the following order of regulatory importance: fluctuating arterial blood gases (in particularly, partial pressure of carbon dioxide), cerebral metabolism, arterial blood pressure, neurogenic activity and cardiac output. Unfortunately, the magnitude that these integrative and synergistic relationships contribute to governing the CBF during exercise remains unclear. Despite some evidence indicating that CBF regulation during exercise is dependent on the changes of blood pressure, neurogenic activity and cardiac output, their role as a primary governor of the CBF response to exercise remains controversial. In contrast, the balance between the partial pressure of carbon dioxide and cerebral metabolism continues to gain empirical support as the primary contributor to the intensity-dependent changes in CBF observed during submaximal, moderate and maximal exercise. The goal of this review is to summarize the fundamental physiology and mechanisms involved in regulation of CBF and metabolism during exercise. The clinical implications of a better understanding of CBF during exercise and new research directions are also outlined.
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Affiliation(s)
- Kurt J Smith
- Cardiovascular Research Group, School of Sports Science, Exercise and Health, University of Western Australia, Crawley, WA, Australia.,Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
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16
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Lundby C, Calbet J, van Hall G, Saltin B, Sander M. Sustained sympathetic activity in altitude acclimatizing lowlanders and high-altitude natives. Scand J Med Sci Sports 2017; 28:854-861. [DOI: 10.1111/sms.12976] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2017] [Indexed: 12/12/2022]
Affiliation(s)
- C. Lundby
- Copenhagen Muscle Research Centre (CMRC); Rigshospitalet; Copenhagen Denmark
- Center for Physical Activity Research; Rigshospitalet; Copenhagen Denmark
| | - J. Calbet
- Copenhagen Muscle Research Centre (CMRC); Rigshospitalet; Copenhagen Denmark
- Department of Physical Education; Research Institute of Biomedical and Health Sciences (IUIBS); University of Las Palmas de Gran Canaria; Las Palmas Spain
| | - G. van Hall
- Copenhagen Muscle Research Centre (CMRC); Rigshospitalet; Copenhagen Denmark
- Endocrinology Research Section; Rigshospitalet; Copenhagen Denmark
| | - B. Saltin
- Copenhagen Muscle Research Centre (CMRC); Rigshospitalet; Copenhagen Denmark
| | - M. Sander
- Copenhagen Muscle Research Centre (CMRC); Rigshospitalet; Copenhagen Denmark
- Kardiologisk Afdeling Y; Bispebjerg Hospital; Copenhagen Denmark
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17
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Ellis LA, Ainslie PN, Armstrong VA, Morris LE, Simair RG, Sletten NR, Tallon CM, McManus AM. Anterior cerebral blood velocity and end-tidal CO 2 responses to exercise differ in children and adults. Am J Physiol Heart Circ Physiol 2017; 312:H1195-H1202. [PMID: 28389601 DOI: 10.1152/ajpheart.00034.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 03/24/2017] [Accepted: 03/28/2017] [Indexed: 11/22/2022]
Abstract
Little is known about the response of the cerebrovasculature to acute exercise in children and how these responses might differ with adults. Therefore, we compared changes in middle cerebral artery blood velocity (MCAVmean), end-tidal Pco2 ([Formula: see text]), blood pressure, and minute ventilation (V̇e) in response to incremental exercise between children and adults. Thirteen children [age: 9 ± 1 (SD) yr] and thirteen sex-matched adults (age: 25 ± 4 yr) completed a maximal exercise test, during which MCAVmean, [Formula: see text], and V̇e were measured continuously. These variables were measured at rest, at exercise intensities specific to individual ventilatory thresholds, and at maximum. Although MCAVmean was higher at rest in children compared with adults, there were smaller increases in children (1-12%) compared with adults (12-25%) at all exercise intensities. There were alterations in [Formula: see text] with exercise intensity in an age-dependent manner [F(2.5,54.5) = 7.983, P < 0.001; η2 = 0.266], remaining stable in children with increasing exercise intensity (37-39 mmHg; P > 0.05) until hyperventilation-induced reductions following the respiratory compensation point. In adults, [Formula: see text] increased with exercise intensity (36-45 mmHg, P < 0.05) until the ventilatory threshold. From the ventilatory threshold to maximum, adults showed a greater hyperventilation-induced hypocapnia than children. These findings show that the relative increase in MCAVmean during exercise was attenuated in children compared with adults. There was also a weaker relationship between MCAVmean and [Formula: see text] during exercise in children, suggesting that cerebral perfusion may be regulated by different mechanisms during exercise in the child.NEW & NOTEWORTHY These findings provide the first direct evidence that exercise increases cerebral blood flow in children to a lesser extent than in adults. Changes in end-tidal CO2 parallel changes in cerebral perfusion in adults but not in children, suggesting age-dependent regulatory mechanisms of cerebral blood flow during exercise.
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Affiliation(s)
- Lindsay A Ellis
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Victoria A Armstrong
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Laura E Morris
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Ryan G Simair
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Nathan R Sletten
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Christine M Tallon
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Ali M McManus
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
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18
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Puthon L, Bouzat P, Robach P, Favre-Juvin A, Doutreleau S, Verges S. Effect of ageing on hypoxic exercise cardiorespiratory, muscle and cerebral oxygenation responses in healthy humans. Exp Physiol 2017; 102:436-447. [DOI: 10.1113/ep085949] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 01/20/2017] [Indexed: 02/04/2023]
Affiliation(s)
- Lara Puthon
- U1042, INSERM, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- HP2 Laboratory, Université Grenoble Alpes, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- Acute Care Unit; Grenoble University Hospital; F-38042 Grenoble France
| | - Pierre Bouzat
- Acute Care Unit; Grenoble University Hospital; F-38042 Grenoble France
- Grenoble Institute of Neurosciences; INSERM U836, BP 217 F-38043 Grenoble France
| | - Paul Robach
- U1042, INSERM, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- HP2 Laboratory, Université Grenoble Alpes, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- National School for Mountain Sports (ENSM); F-74400 Chamonix France
| | - Anne Favre-Juvin
- U1042, INSERM, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- HP2 Laboratory, Université Grenoble Alpes, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
| | - Stéphane Doutreleau
- U1042, INSERM, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- HP2 Laboratory, Université Grenoble Alpes, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
| | - Samuel Verges
- U1042, INSERM, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
- HP2 Laboratory, Université Grenoble Alpes, Building Jean Roget; Faculty of Medicine; F-38042 Grenoble France
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19
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Braz ID, Fisher JP. The impact of age on cerebral perfusion, oxygenation and metabolism during exercise in humans. J Physiol 2016; 594:4471-83. [PMID: 26435295 PMCID: PMC4983626 DOI: 10.1113/jp271081] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 09/24/2015] [Indexed: 01/05/2023] Open
Abstract
Age is one of the most important risk factors for dementia and stroke. Examination of the cerebral circulatory responses to acute exercise in the elderly may help to pinpoint the mechanisms by which exercise training can reduce the risk of brain diseases, inform the optimization of exercise training programmes and assist with the identification of age-related alterations in cerebral vascular function. During low-to-moderate intensity dynamic exercise, enhanced neuronal activity is accompanied by cerebral perfusion increases of ∼10-30%. Beyond ∼60-70% maximal oxygen uptake, cerebral metabolism remains elevated but perfusion in the anterior portion of the circulation returns towards baseline, substantively because of a hyperventilation-mediated reduction in the partial pressure of arterial carbon dioxide (P aC O2) and cerebral vasoconstriction. Cerebral perfusion is lower in older individuals, both at rest and during incremental dynamic exercise. Nevertheless, the increase in the estimated cerebral metabolic rate for oxygen and the arterial-internal jugular venous differences for glucose and lactate are similar in young and older individuals exercising at the same relative exercise intensities. Correction for the age-related reduction in P aC O2 during exercise by the provision of supplementary CO2 is suggested to remove ∼50% of the difference in cerebral perfusion between young and older individuals. A multitude of candidates could account for the remaining difference, including cerebral atrophy, and enhanced vasoconstrictor and blunted vasodilatory pathways. In summary, age-related reductions in cerebral perfusion during exercise are partly associated with a lower P aC O2 in exercising older individuals; nevertheless the cerebral extraction of glucose, lactate and oxygen appear to be preserved.
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Affiliation(s)
- Igor D Braz
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - James P Fisher
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
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20
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Smith KJ, Wildfong KW, Hoiland RL, Harper M, Lewis NC, Pool A, Smith SL, Kuca T, Foster GE, Ainslie PN. Role of CO2 in the cerebral hyperemic response to incremental normoxic and hyperoxic exercise. J Appl Physiol (1985) 2016; 120:843-54. [PMID: 26769951 DOI: 10.1152/japplphysiol.00490.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 01/11/2016] [Indexed: 11/22/2022] Open
Abstract
Cerebral blood flow (CBF) is temporally related to exercise-induced changes in partial pressure of end-tidal carbon dioxide (PetCO2 ); hyperoxia is known to enhance this relationship. We examined the hypothesis that preventing PetCO2 from rising (isocapnia) during submaximal exercise with and without hyperoxia [end-tidal Po2(PetO2 ) = 300 mmHg] would attenuate the increases in CBF. Additionally, we aimed to identify the magnitude that breathing, per se, influences the CBF response to normoxic and hyperoxic exercise. In 14 participants, CBF (intra- and extracranial) measurements were measured during exercise [20, 40, 60, and 80% of maximum workload (Wmax)] and during rest while ventilation (V̇e) was volitionally increased to mimic volumes achieved during exercise (isocapnic hyperpnea). While V̇ewas uncontrolled during poikilocapnic exercise, during isocapnic exercise and isocapnic hyperpnea, V̇ewas increased to prevent PetCO2 from rising above resting values (∼40 mmHg). Although PetCO2 differed by 2 ± 3 mmHg during normoxic poikilocapnic and isocapnic exercise, except for a greater poikilocapnic compared with isocapnic increase in blood velocity in the posterior cerebral artery at 60% Wmax, the between condition increases in intracranial (∼12-15%) and extracranial (15-20%) blood flow were similar at each workload. The poikilocapnic hyperoxic increases in both intra- and extracranial blood-flow (∼17-29%) were greater compared with poikilocapnic normoxia (∼8-20%) at intensities >40% Wmax(P< 0.01). During both normoxic and hyperoxic conditions, isocapnia normalized both the intracranial and extracranial blood-flow differences. Isocapnic hyperpnea did not alter CBF. Our findings demonstrate a differential effect of PetCO2 on CBF during exercise influenced by the prevailing PetO2.
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Affiliation(s)
- K J Smith
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - K W Wildfong
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - R L Hoiland
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - M Harper
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - N C Lewis
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - A Pool
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - S L Smith
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - T Kuca
- Department of Anesthesia, Pain and Perioperative Medicine, Department of Critical Care Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - G E Foster
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
| | - P N Ainslie
- Centre for Heart Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and
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BARAK OTTOF, MADDEN DENNIS, LOVERING ANDREWT, LAMBRECHTS KATE, LJUBKOVIC MARKO, DUJIC ZELJKO. Very Few Exercise-Induced Arterialized Gas Bubbles Reach the Cerebral Vasculature. Med Sci Sports Exerc 2015; 47:1798-805. [DOI: 10.1249/mss.0000000000000625] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Flück D, Braz ID, Keiser S, Hüppin F, Haider T, Hilty MP, Fisher JP, Lundby C. Age, aerobic fitness, and cerebral perfusion during exercise: role of carbon dioxide. Am J Physiol Heart Circ Physiol 2014; 307:H515-23. [DOI: 10.1152/ajpheart.00177.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
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 ± 3 yr (±SD)] volunteers of whom 11 were trained (YT) and 10 considered untrained (YUT), and 2) 17 old (O; 66 ± 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 ± 3.1 cm/s and 30 ± 1 mmHg (±SE)] compared with Y (59.3 ± 2.3 cm/s and 34 ± 1 mmHg, P < 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 MCAvmean 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 = 0.46) nor aerobic fitness ( P = 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.
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Affiliation(s)
- Daniela Flück
- Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland
- Institute of Physiology, University of Zürich, Zürich, Switzerland
| | - Igor D. Braz
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Stefanie Keiser
- Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland
- Institute of Physiology, University of Zürich, Zürich, Switzerland
| | - Fabienne Hüppin
- Exercise Physiology, Institute of Human Movement Sciences, ETH Zürich, Zürich, Switzerland
| | - Thomas Haider
- Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Matthias P. Hilty
- Medical Intensive Care Unit, University Hospital of Zürich, Zürich, Switzerland and
| | - James P. Fisher
- Exercise Physiology, Institute of Human Movement Sciences, ETH Zürich, Zürich, Switzerland
| | - Carsten Lundby
- Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland
- Institute of Physiology, University of Zürich, Zürich, Switzerland
- Food and Nutrition and Sport Science, Gothenburg University, Gothenburg, Sweden
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Faull OK, Cotter JD, Lucas SJE. Cerebrovascular responses during rowing: Do circadian rhythms explain morning and afternoon performance differences? Scand J Med Sci Sports 2014; 25:467-75. [DOI: 10.1111/sms.12273] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2014] [Indexed: 11/29/2022]
Affiliation(s)
- O. K. Faull
- School of Physical Education, Sport and Exercise Sciences; University of Otago; Dunedin New Zealand
- Nuffield Department of Clinical Neuroscience; University of Oxford; Oxford UK
| | - J. D. Cotter
- School of Physical Education, Sport and Exercise Sciences; University of Otago; Dunedin New Zealand
| | - S. J. E. Lucas
- Department of Physiology; University of Otago; Dunedin New Zealand
- School of Sport, Exercise & Rehabilitation Sciences; College of Life and Environmental Sciences; University of Birmingham; Birmingham UK
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Hartmann SE, Leigh R, Poulin MJ. Cerebrovascular responses to submaximal exercise in women with COPD. BMC Pulm Med 2014; 14:99. [PMID: 24898136 PMCID: PMC4065610 DOI: 10.1186/1471-2466-14-99] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 03/28/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND COPD patients have decreased physical fitness, and have an increased risk of vascular disease. In the general population, fitness is positively associated with resting cerebral blood flow velocity, however, little is known about the cerebrovascular response during exercise particularly in COPD patients. We hypothesized that COPD patients would have lower cerebral blood flow during exercise secondary to decreased physical fitness and underlying vascular disease. METHODS Cardiopulmonary exercise testing was conducted in 11 women with GOLD stage I-II COPD, and 11 healthy controls to assess fitness. Cerebro- and cardio-vascular responses were compared between groups during two steady-state exercise tests (50% peak O2 consumption and 30 W). The main outcome variable was peak middle cerebral artery blood flow velocity (VP) during exercise using transcranial Doppler ultrasonography. RESULTS Physical fitness was decreased in COPD patients. VP was comparable between COPD and controls (25 ± 22% versus 15 ± 13%, respectively; P > 0.05) when exercising at the same relative intensity, despite patients having higher blood pressure and greater arterial desaturation. However, VP was elevated in COPD (31 ± 26% versus 13 ± 10%; P ≤ 0.05) when exercising at the same workload as controls. CONCLUSIONS Our results are contradictory to our a-priori hypothesis, suggesting that during matched intensity exercise, cerebral blood flow velocity is similar between COPD and controls. However, exercise at a modestly greater workload imposes a large physical demand to COPD patients, resulting in increased CBF compared to controls. Normal activities of daily living may therefore impose a large cerebrovascular demand in COPD patients, consequently reducing their cerebrovascular reserve capacity.
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Affiliation(s)
| | | | - Marc J Poulin
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, AB, Canada.
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25
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Nussbaumer M, Donath L, Fischer M, Schäfer J, Faude O, Zahner L, Schmidt-Trucksäss A, Hanssen H. Effects of acute bouts of endurance exercise on retinal vessel diameters are age and intensity dependent. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9650. [PMID: 24728623 PMCID: PMC4082577 DOI: 10.1007/s11357-014-9650-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 03/24/2014] [Indexed: 05/27/2023]
Abstract
Alterations of retinal vessel diameters are associated with increased cardiovascular risk. We aimed to investigate changes in retinal vessel diameters in response to acute dynamic exercise of different intensities and whether these changes are age dependent. Seventeen healthy seniors (median (IQR) age 68 (65, 69) years) and 15 healthy young adults (median (IQR) age 26 (25, 28) years) first performed a maximal treadmill test (MTT) followed by a submaximal treadmill test (SMTT) and a resting control condition in randomised order. Central retinal arteriolar (CRAE) and central retinal venular (CRVE) diameter equivalents were measured before as well as 5 (t5) and 40 (t40) minutes after exercise cessation using a static retinal vessel analyser. Both exercise intensities induced a significant dilatation in CRAE and CRVE at t5 compared to the control condition (P < 0.001). At t40, the mean increase in CRAE and CRVE was greater for MTT compared to that for SMTT (CRAE 1.7 μm (95 % confidence interval (CI) -0.1, 3.6; P = 0.061); CRVE 2.2 μm (95 % CI 0.4, 4.1; P = 0.019)). However, the estimated difference at t5 between seniors and young adults in their response to MTT compared to SMTT was 5.3 μm (95 % CI 2.0, 8.5; P = 0.002) for CRAE and 4.1 μm (95 % CI -0.4, 8.6; P = 0.076) for CRVE. Wider arteries and veins after maximal versus submaximal exercise for seniors compared to young adults suggest that myogenic vasoconstriction in response to exhaustive exercise may be reduced in seniors. Age-related loss of vascular reactivity has clinical implications since the arteriolar vasoconstriction protects the retinal capillary bed from intraluminal pressure peaks.
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Affiliation(s)
- M. Nussbaumer
- Department of Sport, Exercise and Health, Division of Sports and Exercise Medicine, Medical Faculty, University of Basel, Birsstrasse 320B, 4052 Basel, Switzerland
| | - L. Donath
- Department of Sport, Exercise and Health, Division of Movement and Exercise Science, Medical Faculty, University of Basel, Basel, Switzerland
| | - M. Fischer
- Department of Sport, Exercise and Health, Division of Sports and Exercise Medicine, Medical Faculty, University of Basel, Birsstrasse 320B, 4052 Basel, Switzerland
| | - J. Schäfer
- Department of Sport, Exercise and Health, Division of Sports and Exercise Medicine, Medical Faculty, University of Basel, Birsstrasse 320B, 4052 Basel, Switzerland
- Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, Basel, Switzerland
| | - O. Faude
- Department of Sport, Exercise and Health, Division of Movement and Exercise Science, Medical Faculty, University of Basel, Basel, Switzerland
| | - L. Zahner
- Department of Sport, Exercise and Health, Division of Movement and Exercise Science, Medical Faculty, University of Basel, Basel, Switzerland
| | - A. Schmidt-Trucksäss
- Department of Sport, Exercise and Health, Division of Sports and Exercise Medicine, Medical Faculty, University of Basel, Birsstrasse 320B, 4052 Basel, Switzerland
| | - H. Hanssen
- Department of Sport, Exercise and Health, Division of Sports and Exercise Medicine, Medical Faculty, University of Basel, Birsstrasse 320B, 4052 Basel, Switzerland
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Geriatric dyspnea: doing worse, feeling better. Ageing Res Rev 2014; 15:94-9. [PMID: 24675044 DOI: 10.1016/j.arr.2014.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 03/04/2014] [Accepted: 03/13/2014] [Indexed: 01/03/2023]
Abstract
Older age is associated with a decline in physical fitness and reduced efficiency of the respiratory system. Paradoxically, it is also related to reduced report of dyspnea, that is, the experience of difficult and uncomfortable breathing. Reduced symptom reporting contributes to misdiagnosis or late diagnosis of underlying disease, suboptimal treatment, faster disease progression, shorter life expectancy, lower quality of life for patients, and considerably increased costs for the health care system in an aging society. However, pathways in the complex relationship between dyspnea and age are not well explored yet. We propose a model on geriatric dyspnea that integrates physiological, neurological, psychological and social pathways which link older age with dyspnea perception and expression. We suggest that the seemingly paradox of reduction of dyspnea in older age, despite physiological decline, can be solved by taking age-related changes on these multiple levels into account. In identifying these variables, the Geriatric Dyspnea Model highlights risk factors for reduced dyspnea perception and report in older age and pathways for intervention.
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27
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Caplan GA, Lan Z, Newton L, Kvelde T, McVeigh C, Hill MA. Transcranial Doppler to Measure Cerebral Blood Flow in Delirium Superimposed on Dementia. A Cohort Study. J Am Med Dir Assoc 2014; 15:355-60. [DOI: 10.1016/j.jamda.2013.12.079] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Revised: 12/16/2013] [Accepted: 12/23/2013] [Indexed: 01/14/2023]
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28
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Blood pressure regulation IX: cerebral autoregulation under blood pressure challenges. Eur J Appl Physiol 2013. [PMID: 23737006 DOI: 10.1007/s00421‐013‐2667‐y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Cerebral autoregulation (CA) is integral to the delicate process of maintaining stable cerebral perfusion and brain tissue oxygenation against changes in arterial blood pressure. The last four decades has seen dramatic advances in understanding CA physiology, and the role that CA might play in the causation and progression of disease processes that affect the cerebral circulation such as stroke. However, the translation of these basic scientific advances into clinical practice has been limited by the maintenance of old constructs and because there are persistent gaps in our understanding of how this vital vascular mechanism should be quantified. In this review, we re-evaluate relevant studies that challenge established paradigms about how the cerebral perfusion pressure and blood flow are related. In the context of blood pressure being a major haemodynamic challenge to the cerebral circulation, we conclude that: (1) the physiological properties of CA remain inconclusive, (2) many extant methods for CA characterisation are based on simplistic assumptions that can give rise to misleading interpretations, and (3) robust evaluation of CA requires thorough consideration not only of active vasomotor function, but also the unique properties of the intracranial environment.
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29
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Tzeng YC, Ainslie PN. Blood pressure regulation IX: cerebral autoregulation under blood pressure challenges. Eur J Appl Physiol 2013; 114:545-59. [PMID: 23737006 PMCID: PMC3929776 DOI: 10.1007/s00421-013-2667-y] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 05/21/2013] [Indexed: 12/11/2022]
Abstract
Cerebral autoregulation (CA) is integral to the delicate process of maintaining stable cerebral perfusion and brain tissue oxygenation against changes in arterial blood pressure. The last four decades has seen dramatic advances in understanding CA physiology, and the role that CA might play in the causation and progression of disease processes that affect the cerebral circulation such as stroke. However, the translation of these basic scientific advances into clinical practice has been limited by the maintenance of old constructs and because there are persistent gaps in our understanding of how this vital vascular mechanism should be quantified. In this review, we re-evaluate relevant studies that challenge established paradigms about how the cerebral perfusion pressure and blood flow are related. In the context of blood pressure being a major haemodynamic challenge to the cerebral circulation, we conclude that: (1) the physiological properties of CA remain inconclusive, (2) many extant methods for CA characterisation are based on simplistic assumptions that can give rise to misleading interpretations, and (3) robust evaluation of CA requires thorough consideration not only of active vasomotor function, but also the unique properties of the intracranial environment.
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Affiliation(s)
- Yu-Chieh Tzeng
- Cardiovascular Systems Laboratory, Centre for Translational Physiology, University of Otago, 23A Mein Street, PO Box 7343, Wellington South, New Zealand,
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30
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Murrell CJ, Cotter JD, Thomas KN, Lucas SJE, Williams MJA, Ainslie PN. Cerebral blood flow and cerebrovascular reactivity at rest and during sub-maximal exercise: effect of age and 12-week exercise training. AGE (DORDRECHT, NETHERLANDS) 2013; 35:905-20. [PMID: 22669592 PMCID: PMC3636405 DOI: 10.1007/s11357-012-9414-x] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 04/17/2012] [Indexed: 05/05/2023]
Abstract
Chronic reductions in cerebral blood flow (CBF) and cerebrovascular reactivity to CO2 are risk factors for cerebrovascular disease. Higher aerobic fitness is associated with higher CBF at any age; however, whether CBF or reactivity can be elevated following an exercise training intervention in healthy individuals is unknown. The aim of this study was to assess the effect of exercise training on CBF and cerebrovascular reactivity at rest and during exercise in young and older individuals. Ten young (23 ± 5 years; body mass index (BMI), 26 ± 3 kg m(-2); [Formula: see text], 35 ± 5 ml kg(-1) min(-1)) and 10 older (63 ± 5 years; BMI, 25 ± 3.0 kg m(-2); [Formula: see text], 26 ± 4 ml kg(-1) min(-1)) previously sedentary individuals breathed 5 % CO2 for 3 min at rest and during steady-state cycling exercise (30 and 70 % heart rate range (HRR)) prior to and following a 12-week aerobic exercise intervention. Effects of training on middle cerebral artery blood velocity (MCAv) at rest were unclear in both age groups. The absolute MCAv response to exercise was greater in the young (9 and 9 cm s(-1) (30 and 70 % HRR, respectively) vs. 5 and 4 cm s(-1) (older), P < 0.05) and was similar following training. Cerebrovascular reactivity was elevated following the 12-week training at rest (2.87 ± 0.76 vs. 2.54 ± 1.12 cm s(-1) mm Hg(-1), P = 0.01) and during exercise, irrespective of age. The finding of a training-induced elevation in cerebrovascular reactivity provides further support for exercise as a preventative tool in cerebrovascular and neurological disease with ageing.
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Affiliation(s)
| | - James D. Cotter
- />School of Physical Education, University of Otago, Dunedin, New Zealand
| | - Kate N. Thomas
- />Department of Physiology, University of Otago, Dunedin, New Zealand
| | | | | | - Philip N. Ainslie
- />School of Health and Exercise Sciences, University of British Columbia, Okanagan Campus, Kelowna, Canada
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Fisher JP, Hartwich D, Seifert T, Olesen ND, McNulty CL, Nielsen HB, van Lieshout JJ, Secher NH. Cerebral perfusion, oxygenation and metabolism during exercise in young and elderly individuals. J Physiol 2012; 591:1859-70. [PMID: 23230234 DOI: 10.1113/jphysiol.2012.244905] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We evaluated cerebral perfusion, oxygenation and metabolism in 11 young (22 ± 1 years) and nine older (66 ± 2 years) individuals at rest and during cycling exercise at low (25% W(max)), moderate (50% Wmax), high (75% W(max)) and exhaustive (100% W(max)) workloads. Mean middle cerebral artery blood velocity (MCA V(mean)), mean arterial pressure (MAP), cardiac output (CO) and partial pressure of arterial carbon dioxide (P(aCO2)) were measured. Blood samples were obtained from the right internal jugular vein and brachial artery to determine concentration differences for oxygen (O2), glucose and lactate across the brain. The molar ratio between cerebral uptake of O2 versus carbohydrate (O2-carbohydrate index; O2/[glucose + 1/2 lactate]; OCI), the cerebral metabolic rate of O2 (CMRO2) and changes in mitochondrial O2 tension ( P(mitoO2)) were calculated. 100% W(max) was ~33% lower in the older group. Exercise increased MAP and CO in both groups (P < 0.05 vs. rest), but at each intensity MAP was higher and CO lower in the older group (P < 0.05). MCA V(mean), P(aCO2) and cerebral vascular conductance index (MCA V(mean)/MAP) were lower in the older group at each exercise intensity (P < 0.05). In contrast, young and older individuals exhibited similar increases in CMRO2 (by ~30 μmol (100 g(-1)) min(-1)), and decreases in OCI (by ~1.5) and (by ~10 mmHg) during exercise at 75% W(max). Thus, despite the older group having reduced cerebral perfusion and maximal exercise capacity, cerebral oxygenation and uptake of lactate and glucose are similar during exercise in young and older individuals.
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Affiliation(s)
- James P Fisher
- School of Sport and Exercise Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
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32
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Regional cerebral blood flow distribution during exercise: influence of oxygen. Respir Physiol Neurobiol 2012; 184:97-105. [PMID: 22926137 DOI: 10.1016/j.resp.2012.07.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 07/18/2012] [Accepted: 07/19/2012] [Indexed: 11/22/2022]
Abstract
We investigated regional changes in cerebral artery velocity during incremental exercise while breathing normoxia (21% O2), hyperoxia (100% O2) or hypoxia (16% O2) [n=10; randomized cross over design]. Middle cerebral and posterior cerebral arterial velocities (MCAv and PCAv) were measured continuously using transcranial Doppler ultrasound. At rest, only PCAv was reduced (-7%; P=0.016) with hyperoxia. During low-intensity exercise (40% workload maximum [Wmax]) MCAv (+17 cms(-1); +14cms(-1)) and PCAv (+9cms(-1); +14 cms(-1)) were increased above baseline with normoxia and hypoxia, respectively (P<0.05). The absolute increase from rest in MCAv was greater than the increase in PCAv between 40 and 80% Wmax with normoxia; this greater increase in MCAv was also evident at 60% Wmax with hypoxia and hyperoxia. Hyperoxic exercise resulted in larger absolute (+19 cms(-1)) and relative (+40%) increases in PCAv compared with normoxia. Our findings highlight the selective changes in PCAv during hyperoxic incremental exercise.
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33
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Resting and exercise cerebral blood flow in long-term heart transplant recipients. J Heart Lung Transplant 2012; 31:906-8. [DOI: 10.1016/j.healun.2012.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 04/04/2012] [Accepted: 04/05/2012] [Indexed: 11/19/2022] Open
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