Effect of low-volume combined aerobic and resistance high-intensity interval training on vascular health in people with type 2 diabetes: a randomised controlled trial.

PURPOSE: We compared the effects of low-volume combined aerobic and resistance high-intensity interval training (C-HIIT), combined moderate-intensity continuous training (C-MICT) and waitlist control (CON) on vascular health after 8-weeks of supervised training, and an additional 10-months of self-directed training, in adults with type 2 diabetes (T2D). METHODS: Sixty-nine low active adults with T2D were randomised to 8-weeks of supervised C-HIIT (3 times/week, 78-min/week), C-MICT (current exercise guidelines, 4 times/week, 210-min/week) or CON. CON underwent usual care for 8-weeks before being re-randomised to C-HIIT or C-MICT. This was followed by 10-months of self-directed training for participants in C-HIIT and C-MICT. Vascular outcomes were evaluated at baseline, 8-weeks, and 12-months. RESULTS: After 8-weeks, supervised C-HIIT significantly improved relative flow-mediated dilation (FMD) compared with CON (mean difference [MD] 0.8% [0.1, 1.4], p = 0.025). Although not significantly different from CON, the magnitude of change in relative FMD following 8-weeks of supervised C-MICT was similar (MD 0.8% [-0.1, 1.7], p = 0.080). There were no differences in haemodynamic indices, carotid-femoral pulse wave velocity (cfPWV), or aortic reservoir pressure between groups at 8-weeks. After 12-months, there was a significant reduction in haemodynamic indices (time effect, p < 0.05) for both C-HIIT and C-MICT, with no between-group difference. The reduction in cfPWV over 12-months was significantly greater in C-MICT than C-HIIT (group × time effect, p = 0.018). There was no difference in FMD over time or between groups at 12-months. CONCLUSIONS: Short-term supervised C-HIIT and C-MICT both increased brachial artery FMD compared with CON. Long-term C-HIIT and C-MICT were beneficial for improving haemodynamic indices, but not brachial artery FMD. C-MICT was superior to C-HIIT for improving cfPWV at 12-months. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

Cardiorespiratory Fitness and Muscular Strength Do Not Predict Social Cognitive Capacity in Older Age.

OBJECTIVES: Social cognitive function often declines in older age but the mechanisms underlying these declines are not completely clear. Cardiorespiratory fitness (CRF) and muscular strength are positively associated with broader cognitive function in older adults, yet surprisingly, no study has examined whether a similar relationship exists between CRF or muscular strength and social cognition in older age. METHODS: We assessed whether higher CRF and muscular strength were associated with enhanced social cognitive function in a sample of fifty older adults (Mage = 70.08, standard deviation = 3.93). Participants completed a gold-standard cardiopulmonary exercise test to assess CRF, an isometric handgrip strength test to index muscular strength, and validated measures of social cognition to index emotion perception and theory of mind (ToM). RESULTS: The results showed that CRF and muscular strength did not explain any unique variance in older adults' social cognitive performance. Bayesian analyses confirmed that the evidence for the null hypothesis was moderate for all tested relationships, except for the relationship between CRF and cognitive ToM where the evidence for the null was anecdotal. DISCUSSION: This study has provided the first evidence to suggest that CRF and muscular strength-two important modifiable lifestyle factors-are not associated with social cognition in healthy older adults. However, replication studies are now needed to cross-validate these findings and to clarify whether any moderating variables may be important for understanding the relationship between fitness and social cognition in older age.

Agreement between left and right middle cerebral artery blood velocity responses to incremental and constant work-rate exercise in healthy males and females.

Objective.To quantify the agreement between left and right middle cerebral artery blood velocity (MCAv) responses to incremental and constant work-rate exercise in adults.ApproachSeventeen healthy adults (23.8 ± 2.4 years, 9 females) completed a ramp incremental test to exhaustion on a cycle ergometer, three 6-minute transitions at a moderate-intensity, and three at a heavy-intensity, all on separate days. Bilateral MCAv was measured throughout using transcranial Doppler ultrasonography, with left and right MCAv data analysed separately. Data were analysed at baseline, gas exchange threshold, respiratory compensation point and exhaustion during ramp incremental exercise. MCAv responses to constant work-rate exercise were analysed using a mono-exponential model, to determine time- and amplitude-based kinetic response parameters.Main ResultsLeft and right MCAv responses to incremental and constant work-rate exercise were significantly, strongly and positively correlated (r≥ 0.61,P< 0.01). Coefficient of variation (left versus right) ranged from 7.3%-20.7%, 6.4%-26.2% and 5.9%-22.5% for ramp, moderate and heavy-intensity exercise, respectively. The relative change in MCAv from baseline was higher in the right compared to left MCAv during ramp, moderate and heavy-intensity exercise (allP< 0.05), but the effect sizes were small (d≤ 0.4). Small mean left-right differences were present during ramp incremental exercise at all time-points (<6 cm s-1; <4%), and for all kinetic parameters during moderate and heavy-intensity exercise (<3 cm s-1, <3%, <4 s).SignificanceThese findings demonstrate similarities between left and right MCAv responses to incremental and constant-work rate exercise in adults on a group-level, but also highlight individual variation in the agreement between left and right MCAv exercise responses.

Efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus: A randomized SHAM-controlled trial.

AIMS: To determine the efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus (T2D), and any persistent benefits 7 weeks following treatment. METHODS: 50 participants with T2D were randomly assigned to either 1) 20x45-minute ECP sessions over 7 weeks (ECP45), 2) 20x30-minute ECP sessions over 7 weeks (ECP30) or 3) SHAM control. Outcomes were assessed at baseline, after 7 weeks of the intervention and 7 weeks after the interventions finished. Efficacy was determined from changes in HbA1c. RESULTS: After 7 weeks, there were significant between-group differences, with ECP45 lowering HbA1c compared to SHAM (mean [95% CI] -0.7 [-0.1 to -1.3] %; -7 [-1 to -15] mmol/mol). Within group changes were; ECP45 (mean ± SD -0.8 ± 0.8%; -8 ± 8 mmol/mol), ECP30 (-0.2 ± 0.5%; -2 ± 6 mmol/mol) and SHAM (-0.1 ± 0.9%; -1 ± 10 mmol/mol). HbA1c in the ECP45 group remained lower 7 weeks after completing the intervention; ECP45 (7.0 ± 1.1%; 53 ± 26 mmol/mol), ECP30 (7.7 ± 1.4%; 60 ± 16 mmol/mol) and SHAM (7.7 ± 1.0%; 60 ± 10 mmol/mol). CONCLUSIONS: In people with T2D, ECP45 for 7 weeks improved glycemic control when compared to ECP30 and a SHAM control group.

Sex modifies the relationship between age and neurovascular coupling in healthy adults.

Neurovascular coupling (NVC) is the matching between local neuronal activity and regional cerebral blood flow (CBF), but little is known about the effects of age and sex on NVC. This study aimed to investigate the relationships and interaction between age and sex on NVC. Sixty-four healthy adults (18-85 years, N = 34 female) completed a visual stimulus evoked NVC assessment to a flashing checkerboard. NVC responses were measured in the posterior cerebral artery (PCAv) using transcranial Doppler ultrasound. A hierarchical multiple regression was used to determine the relationships between age, sex, and the age by sex interaction on NVC. There was a significant age by sex interaction for baseline (P = 0.001) and peak PCAv (P = 0.01), with a negative relationship with age in females (P < 0.005), and no relationship in males (P ≥ 0.17). NVC responses as a percent increase from baseline showed a significant age by sex interaction (P = 0.014), with a positive relationship with age in females (P = 0.04) and no relationship in males (P = 0.17), even after adjusting for baseline PCAv. These data highlight important sex differences, with an association between age and NVC only apparent in females but not males, and thus a need to account for sex dependent effects of ageing when investigating cerebrovascular regulation.

Efficacy of exercise training for improving vascular dysfunction in people with cancer: a systematic review with meta-analyses.

PURPOSE: Cancer treatments exert vascular toxic effects that can lead to the development of cardiovascular disease. Exercise training has the potential to prevent or reduce cancer treatment-induced damage to vascular structure and function. This systematic review with meta-analyses aimed to determine the isolated effects of exercise training on vascular outcomes in people with cancer. METHODS: Seven electronic databases were searched on 20 September 2021 to identify randomised controlled trials, quasi-randomised trials, pilot and cohort studies. Included studies implemented a structured exercise intervention and assessed vascular structure and/or function in people during or following cancer treatment. Meta-analyses examined the effects of exercise training on endothelial function (via brachial artery flow-mediated dilation) and arterial stiffness (via pulse wave velocity). Methodological quality was assessed using the Cochrane Quality Assessment tool and modified Newcastle-Ottawa Quality Appraisal tool. Grading of Recommendations, Assessment, Development and Evaluations framework was used to assess the certainty of evidence. RESULTS: Ten studies (discussed across 11 articles) met the inclusion criteria. Methodological quality of the included studies was moderate (71% average). Exercise improved vascular function when compared to control (standardised mean difference = 0.34, 95% CI (0.01, 0.67); p = 0.044: studies = 5, participants = 171), but not pulse wave velocity (standardised mean difference = - 0.64, 95% CI (- 1.29, 0.02); p = 0.056: studies = 4, participants = 333). The certainty of evidence was moderate for flow-mediated dilation and low for pulse wave velocity. CONCLUSIONS: Compared to usual care, exercise training significantly improves flow-mediated dilation (endothelial function) but not pulse wave analysis, in people treated for cancer. IMPLICATIONS FOR CANCER SURVIVORS: Exercise may improve vascular health in individuals during and following cancer treatment.

Economic evaluation of exercise interventions for individuals with cancer: A systematic review.

While there is good evidence that exercise is an effective adjunct therapy to cancer care, little is known about its value for money. The aim of this systematic review is to explore the available evidence pertaining to the cost-effectiveness of exercise interventions following cancer. A search of eight online databases (CINAHL, the Cochrane Library (NHSEED), Econlit, Embase, PsycInfo, PubMed, Scopus, Web of science) was first conducted on 26 March 2021 and updated on 8 March 2022. Only economic evaluations with results in the form of incremental cost-effectiveness ratio (ICER) were included. The Consolidated Health Economics Evaluation Reporting Standards (CHEERS) was used to appraise the quality of reporting in the studies. The study protocol was registered in PROSPERO. Sixteen studies comprising seven (44%) cost-utility analyses (CUA), one (6%) cost-effectiveness analyses (CEA) and eight (50%) combined CUA and CEA were identified. These studies explored exercise in five cancer types (breast, colon, lung, prostate, and blood), with half (50%) in breast cancer. Seven studies (44%) adopted societal perspectives. Exercise interventions were found to be cost-effective in five of ten (50%) trial-based economic evaluations and in five of the six (83%) model-based economic evaluations. Most exercise interventions included were supervised, while close supervision and individualized exercise sessions incurred higher costs. Exercise interventions in cancer care are cost-effective for various cancer types despite considerable heterogeneity in exercise delivery and the type of analysis used for economic evaluation. There is clear value in using decision-analytic modelling to account for the long-term benefits of exercise in cancer care.

Comparison of peripheral and cerebral vascular function between premenopausal, early and late postmenopausal females.

NEW FINDINGS: What is the central question of this study? We sought to investigate whether peripheral and cerebrovascular function are impaired in early and late postmenopausal females compared with premenopausal females, while also accounting for nitric oxide and estradiol levels. What is the main finding and its importance? We observed no differences in peripheral vascular and cerebrovascular function between healthy and physically active premenopausal females and early and late postmenopausal females. Our findings contradict previous cross-sectional observations of vascular and cerebrovascular dysfunction across menopause. Longitudinal studies assessing vascular and cerebrovascular outcomes across the menopausal transition are warranted. ABSTRACT: The risk of cardiovascular and cerebrovascular disease increases in ageing females, coinciding with the onset of menopause. Differences in peripheral and cerebrovascular function across menopausal stages, however, are poorly characterized. The aim of this study was to compare peripheral and cerebrovascular function between healthy premenopausal (PRE), early (1-6 years after final menstrual period; E-POST) and late (>6 years after final menstrual period; L-POST) postmenopausal females. We also explored the association between reproductive hormones, NO bioavailability and cerebrovascular function. In 39 females (40-65 years of age), we measured arterial stiffness, brachial artery flow-mediated dilatation, and cerebrovascular reactivity (CVR) to hypercapnia in the middle (MCAv) and internal (ICA) carotid arteries. Follicle-stimulating hormone, estradiol, progesterone and plasma nitrate and nitrite concentrations were also measured. Years since final menstrual period (PRE, 0 ± 0 years; E-POST, 3 ± 1 years; L-POST, 11 ± 4 years; P < 0.001) and estradiol levels (PRE, 145.5 ± 65.6 pg ml-1 ; E-POSTm 30.2 ± 81.2 pg ml-1 ; L-POST, 7.7 ± 11.3 pg ml-1 ; P < 0.001) were different between groups. All groups exceeded the guidelines for recommended physical activity. There were no group differences in blood pressure (P = 0.382), arterial stiffness (P = 0.129), flow-mediated dilatation (P = 0.696) or MCAv CVR (P = 0.442). The ICA CVR blood flow response was lower in PRE compared with L-POST (26.5 ± 19.2 vs. 47.8 ± 12.6%; P = 0.010), but after adjusting for age these differences were no longer present. Flow-mediated dilatation (r = 0.313, P = 0.105) and ICA CVR (r = -0.154, P = 0.495) were not associated with the estradiol concentration. There were no associations between the estradiol concentration and NO bioavailability. These results suggest that in healthy, physically active early and late postmenopausal females, vascular and cerebrovascular function is generally well preserved.

The relationships between age, sex, and cerebrovascular reactivity to hypercapnia using traditional and kinetic-based analyses in healthy adults.

The effect of age and sex on intracranial and extracranial cerebrovascular function is poorly understood. We investigated the relationships between age, sex, and cerebrovascular reactivity (CVR) to hypercapnia in 73 healthy adults (18-80 yr, n = 39 female). CVR to hypercapnia was assessed in the middle cerebral artery (MCA) using transcranial Doppler ultrasound and at the internal carotid artery (ICA) using duplex ultrasound. MCA CVR was characterized by peak MCA velocity (MCAv) response per mmHg increase in end-tidal CO2 and by using a monoexponential model to characterize the kinetics (time constant) of the MCAv response. ICA reactivity was assessed as the relative peak increase in artery diameter. Hierarchical multiple regression determined the relationships between age, sex, and the age-by-sex interaction on all baseline and CVR outcomes. There was no relationship between ICA reactivity (%) with age (P = 0.07), sex (P = 0.56), or a moderator effect of sex on the age effect (P = 0.24). MCAv CVR showed no relationship with age (P = 0.59), sex (P = 0.09), or an age-by-sex moderator effect (P = 0.90). We observed a positive relationship of MCAv CVR time constant with age (P = 0.013), such that the speed of the MCA response was slower with advancing age. The present study provides comprehensive data on age- and sex-specific relationships with intracranial and extracranial cerebrovascular responses to hypercapnia. Despite similar MCAv CVR and ICA reactivity between sexes, kinetic responses of the MCA revealed a slower rate of adjustment with advancing age.NEW & NOTEWORTHY We observed similar MCA CVR and ICA reactivity in males and females. However, kinetic responses of the MCA to hypercapnia suggest that advancing age slows down the rate at which MCA velocity increases in response to hypercapnia. These data indicate distinct regulatory differences, and an impaired vasomotor control of the cerebrovasculature with advancing age, not detected by traditional methods.

The effect of exercise intensity and cardiorespiratory fitness on the kinetic response of middle cerebral artery blood velocity during exercise in healthy adults.

The aim of this study was to compare the kinetic response of middle cerebral artery blood velocity (MCAv) to moderate- and heavy-intensity cycling in adults, and explore the relationship between maximal oxygen uptake (V̇o2max) and MCAv kinetics. Seventeen healthy adults (23.8 ± 2.4 yr, 9 females) completed a ramp incremental test to exhaustion on a cycle ergometer to determine V̇o2max and the gas exchange threshold (GET). Across six separate visits, participants completed three 6-min transitions at a moderate intensity (90% GET) and three at a heavy intensity (40% of the difference between GET and V̇o2max). Bilateral MCAv was measured using transcranial Doppler (TCD) ultrasonography and analyzed using a monoexponential model with a time delay. The time constant (τ) of the MCAv response was not different between moderate- and heavy-intensity cycling (25 ± 10 vs. 26 ± 8 s, P = 0.82), as was the time delay (29 ± 11 vs. 29 ± 10 s, P = 0.95). The amplitude of the exponential increase in MCAv from baseline was greater during heavy-intensity cycling (23.9 ± 10.0 cm·s-1, 34.1 ± 14.4%) compared with moderate-intensity cycling (12.7 ± 4.4 cm·s-1, 18.7 ± 7.5%; P < 0.01). Following the exponential increase, a greater fall in MCAv was observed during heavy-intensity exercise compared with moderate-intensity exercise (9.5 ± 6.9 vs. 2.8 ± 3.8 cm·s-1, P < 0.01). MCAv after 6 min of exercise remained elevated during heavy-intensity exercise compared with moderate-intensity exercise (85.2 ± 9.6 vs. 79.3 ± 7.7 cm·s-1, P ≤ 0.01). V̇o2max was not correlated with MCAv τ or amplitude (r = 0.11-0.26, P > 0.05). These data suggest that the intensity of constant-work rate exercise influences the amplitude, but not time-based, response parameters of MCAv in healthy adults, and found no relationship between cardiorespiratory fitness and MCAv kinetics.NEW & NOTEWORTHY This is the first study to model the MCAv kinetic response to moderate- and heavy-intensity cycling in healthy adults. This study found that the amplitude of the exponential rise in MCAv at exercise onset was greater during heavy-intensity exercise (∼34%) compared with moderate-intensity exercise (∼19%), but the time-based characteristics of the responses were similar between intensities. Higher cardiorespiratory fitness was not associated with a greater or faster MCAv response to moderate- or heavy-intensity exercise.

Cerebrovascular function and its association with systemic artery function and stiffness in older adults with and without mild cognitive impairment.

PURPOSE: Our aim was to compare cerebrovascular and systemic vascular function between older adults with and without mild cognitive impairment (MCI), and to determine which measures of vascular function best predict the presence of MCI. METHODS: In 41 adults with MCI and 33 adults without MCI (control) we compared middle cerebral artery velocity (MCAv) and cerebrovascular pulsatility index (PI) at rest, cerebrovascular reactivity to CO2, and responsiveness to changes in blood pressure (%∆MCAv/%∆MAP). Systemic vascular function was assessed by flow-mediated dilation (FMD) and stiffness by pulse wave velocity (PWV). RESULTS: Cerebrovascular PI was higher in MCI compared with control (mean ± SD: 1.17 ± 0.27 vs. 1.04 ± 0.21), and MCI exhibited a lower %∆MCAv/%∆MAP (1.26 ± 0.44 vs. 1.50 ± 0.55%). Absolute (p = 0.76) and relative cerebrovascular reactivity to CO2 (p = 0.34) was similar between MCI and control. When age was included as a covariate the significant difference in cerebral PI between groups was lost. PWV was higher (13.2 ± 2.2 vs. 11.3 ± 2.5 m s-1) and FMD% (4.41 ± 1.70 vs. 5.43 ± 2.15%) was lower in MCI compared with control. FMD% was positively associated with PI across the cohort. Logistic regression analysis indicated that FMD and PWV significantly discriminated between MCI and controls, independent of age, whereas the inclusion of cerebrovascular measures did not improve the predictive accuracy of the model. CONCLUSION: These findings raise the possibility that early changes in systemic vascular stiffness and endothelial function may contribute to altered cerebrovascular haemodynamics and impaired cognitive function, and present potential targets for prevention and treatment strategies in people with MCI.

Effects of fitness and fatness on age-related arterial stiffening in people with type 2 diabetes.

People with type 2 diabetes (T2D) are at a greater risk of cardiovascular disease than the general population. Both non-modifiable (age) and modifiable (low aerobic fitness, high body fatness) factors are separately predictive of cardiovascular risk, although they often occur concomitantly. This study aimed to examine the (1) association between age and arterial stiffness, a subclinical marker of cardiovascular risk; and (2) effects of body fatness and aerobic fitness on age-related increases in arterial stiffness in people with T2D. Data from 64 individuals with T2D (age 59.8 ± 8.7 years, 40% female, HbA1c 8.4 ± 1.6%) were included in this cross-sectional analysis. Carotid-femoral pulse wave velocity (cfPWV) was used to quantify arterial stiffness. Aerobic fitness (relative V̇O2peak ) was determined via indirect calorimetry during maximal exercise testing. Central body fatness was determined using waist circumference. Data were analysed using hierarchical multiple regressions. After adjustment for sex and duration of T2D, each one standard deviation (SD) increase in age (8.68 years) was associated with a 0.63 m·s-1 increase in cfPWV (ß = 0.416, p = 0.001). Following adjustment for aerobic fitness and body fatness, the standardized ß was unchanged (0.417). A one SD increase in waist circumference (13.9 cm) and relative V̇O2peak (5.3 ml·kg-1 ·min-1 ) were associated with a similar magnitude of difference in cfPWV (0.47 m·s-1 and -0.44 m·s-1 , respectively). Therefore, age is a significant correlate of increased arterial stiffness in T2D, with higher aerobic fitness attenuating, and higher body fatness exacerbating, this increase. Interventions aimed at improving cardiovascular outcomes in people with T2D should target both increased aerobic fitness and reduced body fatness.

The physiological and clinical importance of cardiorespiratory fitness in people with abdominal aortic aneurysm.

NEW FINDINGS: What is the topic of this review? This review focuses on the physiological impact of abdominal aortic aneurysm (AAA) on cardiorespiratory fitness and the negative consequences of low fitness on clinical outcomes in AAA. We also discuss the efficacy of exercise training for improving cardiorespiratory fitness in AAA. What advances does it highlight? We demonstrate the negative impact of low fitness on disease progression and clinical outcomes in AAA. We highlight potential mechanistic determinants of low fitness in AAA and present evidence that exercise training can be an effective treatment strategy for improving cardiorespiratory fitness, postoperative mortality and disease progression. ABSTRACT: An abdominal aortic aneurysm (AAA) is an abnormal enlargement of the aorta, below the level of the renal arteries, where the aorta diameter increases by >50%. As an aneurysm increases in size, there is a progressive increase in the risk of rupture, which ranges from 25 to 40% for aneurysms >5.5 cm in diameter. People with AAA are also at a heightened risk of cardiovascular events and associated mortality. Cardiorespiratory fitness is impaired in people with AAA and is associated with poor (postoperative) clinical outcomes, including increased length of hospital stay and postoperative mortality after open surgical or endovascular AAA repair. Although cardiorespiratory fitness is a well-recognized prognostic marker of cardiovascular health and mortality, it is not assessed routinely, nor is it included in current clinical practice guidelines for the management of people with AAA. In this review, we discuss the physiological impact of AAA on cardiorespiratory fitness, in addition to the consequences of low cardiorespiratory fitness on clinical outcomes in people with AAA. Finally, we summarize current evidence for the effect of exercise training interventions on cardiorespiratory fitness in people with AAA, including the associated improvements in postoperative mortality, AAA growth and cardiovascular risk. Based on this review, we propose that cardiorespiratory fitness should be considered as part of the routine risk assessment and monitoring of people with AAA and that targeting improvements in cardiorespiratory fitness with exercise training might represent a viable adjunct treatment strategy for reducing postoperative mortality and disease progression.

Alcohol and Breast Cancer: Results From the Women's Wellness After Cancer Program Randomized Controlled Trial.

BACKGROUND: There is evidence that drinking alcohol increases the risk of recurrent breast cancer. It is unclear whether Australian women with breast cancer are aware of this evidence or modify their alcohol intake accordingly. OBJECTIVE: This article reports a secondary analysis of data from the Women's Wellness after Cancer Program (WWACP) randomized controlled trial (N = 351). The WWACP aimed to enhance quality of life and reduce chronic disease risk in women previously treated for cancer through lifestyle modification. Here we provide the alcohol-related data from the study's breast cancer participants (n = 269). We analyzed baseline alcohol consumption, the variables associated with alcohol intake, and intervention effect on intake at weeks 12 (end of intervention) and 24 (to determine sustainability). INTERVENTIONS/METHODS: Measures included the Dietary Questionnaire for Epidemiological Studies, Short Form-36, International Physical Activity Questionnaire, Green Climacteric Scale, Pittsburgh Sleep Quality Index, and Center for Epidemiologic Studies Depression Scale. RESULTS: Most participants practiced safe alcohol consumption. Among drinkers, drinking caffeine, smoking, emotional and physical role limitations, and greater discomfort with vasomotor symptoms were associated with increased intake. Relative to baseline, alcohol consumption decreased from 5.22 g/d to 4.18 g/d in the intervention group, whereas consumption increased among control subjects at 12 weeks. No difference between groups was observed at week 24. CONCLUSION: The intervention was associated with less alcohol intake at week 12 among drinkers, but this reduction was not sustained at the 24-week follow-up. IMPLICATIONS FOR PRACTICE: Future iterations of the WWACP will emphasize stronger messaging and supports regarding alcohol consumption after breast cancer treatment.

The within- and between-day reliability of cerebrovascular reactivity using traditional and novel analytical approaches.

NEW FINDINGS: What is the central question of the study? What is the reliability of middle cerebral artery velocity cerebrovascular reactivity (CVR) when using traditional and novel outcomes, as measured by transcranial Doppler? What is the main finding and its importance? Traditional CVR approaches presented acceptable reproducibility but should be expressed as an absolute CVR. Large within- and between-individual differences in the middle cerebral artery velocity response profile support using a dynamic peak, rather than a set time point, for the most reliable interpretation. The study highlights the utility of novel kinetic CVR outcomes, but due to increased variability in time-based metrics, this analysis requires larger sample sizes than traditional methods. ABSTRACT: Cerebrovascular reactivity (CVR) of middle cerebral artery velocity (MCAv) to CO2 is a common method to assess cerebrovascular function. Yet, the approaches used to calculate CVR outcomes vary. The aim of this study was to explore the within- and between-day reliability of traditional CVR outcomes. The second aim was to explore the reliability of novel kinetic-based analyses. Healthy adults (n = 10, 22.3 ± 3.4 years) completed assessments of CVR over 4 min using a fixed fraction of inspired CO2 (6%). This was repeated across four separate visits (between-day), and on one visit measures were repeated 2.5 h later (within-day). No mean biases were present between assessments for traditional CVR metrics, expressed as absolute (cm/s/mmHg) or relative (%/mmHg) outcomes (minute 3, minute 4, peak 1 s, peak 30 s) (between-day: P > 0.14, ηp2 < 0.20; within-day: P > 0.22, d > 0.27). Absolute, rather than relative, CVR yielded the most reproducible parameters (coefficient of variation: 8.1-13.2% vs. 14-83%, respectively). There were significant differences between CVR outcomes (P < 0.001, ηp2 > 0.89) dependent on the time point used to determine CVR, as a steady state MCAv response was rarely observed. Furthermore, the MCAv response was not reproducible within an individual (κ = 0.15, P = 0.09). No mean differences were present for novel kinetic outcomes (amplitude, time-delay, time constant) (between-day: P > 0.05, d < 0.33; within-day: P > 0.38, d < 0.25). The results support the need for standardisation and indicate CVR should be defined as a dynamic peak, rather than a set time point for increased reliability. For novel kinetic outcomes variability was greater (CV: 8.7-120.9%) due to the nature of time-based metrics.

Comparison of high intensity interval training with standard cardiac rehabilitation on vascular function.

OBJECTIVES: To compare the short- and long-term effects of high-intensity interval training (HIIT) with usual care moderate intensity continuous training (MICT) on systemic vascular function and stiffness in patients with coronary artery disease undergoing a cardiac rehabilitation program. DESIGN: Randomized controlled trial. METHODS: Fifty-four patients (age = 63 ± 8 years, 93% male) were randomized to complete 3 sessions/week (2 supervised, 1 home-based) of either (1) 4 × 4-min HIIT or (2) 40-min MICT, for 4 weeks. Patients then continued 3 unsupervised home-based sessions/week of their allocated training for 11 months. Brachial artery flow-mediated dilation, pulse wave velocity, and blood pressure were measured at baseline, 4 weeks, 3 months, 6 months, and 12 months. Data were analyzed using linear mixed modeling and are presented as mean change from baseline (95% CI). RESULTS: HIIT showed a greater improvement in flow-mediated dilation compared to MICT after 4 weeks [1.5% (0.9, 2.1) vs 0.1% (-0.5, 0.8); p = 0.004) but not 12 months [1.2% (-0.2, 2.5) vs 0.4% (-0.8, 1.7); p = 0.153). There were no short- or long-term group differences for changes in pulse wave velocity, peripheral or central blood pressure between HIIT and MICT after 4 weeks, or over 12 months. CONCLUSIONS: A 4-week HIIT program was superior to MICT for improving vascular function, but not arterial stiffness or blood pressure. Over 12 months, changes in vascular function, blood pressure, and arterial stiffness were similar for HIIT and MICT.

Autonomic control of cerebral blood flow: fundamental comparisons between peripheral and cerebrovascular circulations in humans.

Understanding the contribution of the autonomic nervous system to cerebral blood flow (CBF) control is challenging, and interpretations are unclear. The identification of calcium channels and adrenoreceptors within cerebral vessels has led to common misconceptions that the function of these receptors and actions mirror those of the peripheral vasculature. This review outlines the fundamental differences and complex actions of cerebral autonomic activation compared with the peripheral circulation. Anatomical differences, including the closed nature of the cerebrovasculature, and differential adrenoreceptor subtypes, density, distribution and sensitivity, provide evidence that measures on peripheral sympathetic nerve activity cannot be extrapolated to the cerebrovasculature. Cerebral sympathetic nerve activity seems to act opposingly to the peripheral circulation, mediated at least in part by changes in intracranial pressure and cerebral blood volume. Additionally, heterogeneity in cerebral adrenoreceptor distribution highlights region-specific autonomic regulation of CBF. Compensatory chemo- and autoregulatory responses throughout the cerebral circulation, and interactions with parasympathetic nerve activity are unique features to the cerebral circulation. This crosstalk between sympathetic and parasympathetic reflexes acts to ensure adequate perfusion of CBF to rising and falling perfusion pressures, optimizing delivery of oxygen and nutrients to the brain, while attempting to maintain blood volume and intracranial pressure. Herein, we highlight the distinct similarities and differences between autonomic control of cerebral and peripheral blood flow, and the regional specificity of sympathetic and parasympathetic regulation within the cerebrovasculature. Future research directions are outlined with the goal to further our understanding of autonomic control of CBF in humans.

Differences in cerebrovascular regulation and ventilatory responses during ramp incremental cycling in children, adolescents, and adults.

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.

Effect of menopause on cerebral artery blood flow velocity and cerebrovascular reactivity: Systematic review and meta-analysis.

BACKGROUND: Menopause and its associated decline in oestrogen is linked to chronic conditions like cardiovascular disease and osteoporosis, which may be difficult to disentangle from the effects of ageing. Further, post-menopausal women are at increased risk of cerebrovascular disease, linked to declines in cerebral blood flow (CBF) and cerebrovascular reactivity (CVR), yet the direct understanding of the impact of the menopause on cerebrovascular function is unclear. The aim of this systematic review and meta-analysis was to examine the literature investigating CBF and CVR in pre- compared with post-menopausal women METHODS: Five databases were searched for studies assessing CBF or CVR in pre- and post-menopausal women. Meta-analysis examined the effect of menopausal status on middle cerebral artery velocity (MCAv), and GRADE-assessed evidence certainty RESULTS: Nine studies (n=504) included cerebrovascular outcomes. Six studies (n=239) reported negligible differences in MCAv between pre- and post-menopausal women [2.11cm/s (95% CI: -8.94 to 4.73, p=0.54)], but with a "low" certainty of evidence. MCAv was lower in post-menopausal women in two studies, when MCAv was adjusted for blood pressure. CVR was lower in post- compared with pre-menopausal women in two of three studies, but high-quality evidence is lacking. Across outcomes, study methodology and reporting criteria for menopause were inconsistent CONCLUSIONS: MCAv was similar in post- compared with pre-menopausal women. Methodological differences in characterising menopause and inconsistent reporting of cerebrovascular outcomes make comparisons difficult. Comprehensive assessments of cerebrovascular function of the intra- and extracranial arteries to determine the physiological implications of menopause on CBF with healthy ageing is warranted.

Effects of cardiorespiratory fitness and exercise training on cerebrovascular blood flow and reactivity: a systematic review with meta-analyses.

We address two aims: Aim 1 (Fitness Review) compares the effect of higher cardiorespiratory fitness (CRF) (e.g., endurance athletes) with lower CRF (e.g., sedentary adults) on cerebrovascular outcomes, including middle cerebral artery velocity (MCAv), cerebrovascular reactivity and resistance, and global cerebral blood flow, as assessed by transcranial Doppler (TCD) or magnetic resonance imaging (MRI). Aim 2 (Exercise Training Review) determines the effect of exercise training on cerebrovascular outcomes. Systematic review of studies with meta-analyses where appropriate. Certainty of evidence was assessed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Twenty studies (18 using TCD) met the eligibility criteria for Aim 1, and 14 studies (8 by TCD) were included for Aim 2. There was a significant effect of higher CRF compared with lower CRF on cerebrovascular resistance (effect size = -0.54, 95% confidence interval = -0.91 to -0.16) and cerebrovascular reactivity (0.98, 0.41-1.55). Studies including males only demonstrated a greater effect of higher CRF on cerebrovascular resistance than mixed or female studies (male only: -0.69, -1.06 to -0.32; mixed and female studies: 0.10, -0.28 to 0.49). Exercise training did not increase MCAv (0.05, -0.21 to 0.31) but showed a small nonsignificant improvement in cerebrovascular reactivity (0.60, -0.08 to 1.28; P = 0.09). Exercise training showed heterogeneous effects on regional but little effect on global cerebral blood flow as measured by MRI. High CRF positively effects cerebrovascular function, including decreased cerebrovascular resistance and increased cerebrovascular reactivity; however, global cerebral blood flow and MCAv are primarily unchanged following an exercise intervention in healthy and clinical populations.NEW & NOTEWORTHY Higher cardiorespiratory fitness is associated with lower cerebrovascular resistance and elevated cerebrovascular reactivity at rest. Only adults with a true-high fitness based on normative data exhibited elevated middle cerebral artery velocity. The positive effect of higher compared with lower cardiorespiratory fitness on resting cerebrovascular resistance was more evident in male-only studies when compared with mixed or female-only studies. A period of exercise training resulted in negligible changes in middle cerebral artery velocity and global cerebral blood flow, with potential for improvements in cerebrovascular reactivity.