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1.
Microvasc Res ; 155: 104706, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871050

RESUMO

Prior work has yet to determine whether the reduction of dietary nitrate (NO3-) to NO, via the enterosalivary pathway, may modify cutaneous vascular conductance (CVC) responses to local heating in older women. Changes occurring with the transition to menopause related to hormonal flux, increased adiposity, and/or decreased physical activity may further compound the negative influence of aging on nitric oxide (NO)-dependent CVC. Herein, we characterized changes in NO-dependent CVC following acute ingestion of 140 mL of NO3--rich beetroot juice in 24 older women (age: 65 ± 5 y, BMI: 31.2 ± 3.7 kg/m2). Red blood cell (RBC) flux was measured continuously via laser-Doppler flowmetry on the dorsal aspect of the forearm during local skin heating to 39 °C/44 °C before and 3 h after NO3- ingestion. NO-dependent changes in CVC were calculated as RBC flux/mean arterial blood pressure at 39 °C and normalized as a proportion of maximal CVC at 44 °C (%CVCmax). Changes (Δ) in fractional exhaled NO (FeNO) following NO3- ingestion were used an index of NO bioavailability. Despite increased FeNO (+81 ± 70 %, P < 0.001), %CVCmax at 39 °C was reduced (-16 ± 10 %, P < 0.001) following NO3- ingestion. A greater reduction in %CVCmax was weakly to moderately associated with higher body fat% (r = 0.45 [0.05-0.72], P = 0.029), central adiposity% (r = 0.50 [0.13-0.75], P = 0.012), neutrophil% (r = 0.42 [0.02-0.70], P = 0.041), and higher neutrophil to lymphocyte ratio (r = 0.49 [0.11-0.75], P = 0.016). These findings demonstrate a single dose of dietary NO3- does not promote CVC responses to local heating in sedentary older women with overweight and obesity. Correlation with multiple biomarkers suggest systemic inflammation may be involved.

2.
BMJ Open ; 14(5): e081660, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702085

RESUMO

INTRODUCTION: Breast cancer survivors have an increased risk for chronic fatigue and altered gut microbiota composition, both with negative health and quality of life affects. Exercise modestly improves fatigue and is linked to gut microbial diversity and production of beneficial metabolites. Studies suggest that gut microbiota composition is a potential mechanism underlying fatigue response to exercise. Randomised controlled trials testing the effects of exercise on the gut microbiome are limited and there is a scarcity of findings specific to breast cancer survivors. The objective of this study is to determine if fitness-related modifications to gut microbiota occur and, if so, mediate the effects of aerobic exercise on fatigue response. METHODS AND ANALYSIS: The research is a randomised controlled trial among breast cancer survivors aged 18-74 with fatigue. The primary aim is to determine the effects of aerobic exercise training compared with an attention control on gut microbiota composition. The secondary study aims are to test if exercise training (1) affects the gut microbiota composition directly and/or indirectly through inflammation (serum cytokines), autonomic nervous system (heart rate variability) or hypothalamic-pituitary-adrenal axis mediators (hair cortisol assays), and (2) effects on fatigue are direct and/or indirect through changes in the gut microbiota composition. All participants receive a standardised controlled diet. Assessments occur at baseline, 5 weeks, 10 weeks and 15 weeks (5 weeks post intervention completion). Faecal samples collect the gut microbiome and 16S gene sequencing will identify the microbiome. Fatigue is measured by a 13-item multidimensional fatigue scale. ETHICS AND DISSEMINATION: The University of Alabama at Birmingham Institutional Review Board (IRB) approved this study on 15 May 2019, UAB IRB#30000320. A Data and Safety Monitoring Board convenes annually or more often if indicated. Findings will be disseminated in peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT04088708.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Fadiga , Microbioma Gastrointestinal , Humanos , Feminino , Sobreviventes de Câncer/psicologia , Pessoa de Meia-Idade , Adulto , Idoso , Ensaios Clínicos Controlados Aleatórios como Assunto , Exercício Físico/fisiologia , Qualidade de Vida , Terapia por Exercício/métodos , Adulto Jovem , Adolescente
3.
Geriatr Gerontol Int ; 23(10): 715-721, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37650477

RESUMO

AIM: Objective measurements of physcial function, including gait speed, handgrip strength, and the chair stand test, have been shown to have predictive capacity for negative health-related outcomes. The aim of this study was to examine campariatively which of these common assessments may be optimal in terms of their predictive capacity for mortality. METHODS: A total of 9834 community-dwelling older women aged 65-89 years from the Study of Osteoporotic Fractures (SOF) were followed for 20 years. Gait speed, handgrip strength, and the chair stand test were measured every 2-4 years on up to 9 visits. All deaths were adjudicated. RESULTS: All three measurements of physical function were significantly associated with overall, cardiovascular disease and other mortality. Gait speed had the greatest magnitude of hazard ratios (HRs) for all outcomes of interest. A one-unit standard deviation increase in gait speed was associated with a 33% (HR = 0.67, 95% confidence interval [95% CI]: 0.64-0.70) lower risk for overall mortality, a 31% (HR = 0.69, 95% CI: 0.64-0.73) lower risk for cardiovascular disease mortality, a 15% (HR = 0.85, 95% CI: 0.78-0.92) lower risk for cancer mortality and a 42% (HR = 0.58, 95% CI: 0.55-0.62) lower risk for other mortality. Further examination of gait speed identified two cut-points (0.9 and 0.7 m/s) that were strongly indicative of increased mortality risk. CONCLUSION: Our large prospective study indicates that gait speed possesses a better prediction of mortality among older women compared with handgrip strength or the chair stand test. Using cut-points of 0.9 and 0.7 m/s can help identify older women at higher mortality risk, who may benefit from physical function improvement interventions. Geriatr Gerontol Int 2023; 23: 715-721.

4.
Int J Public Health ; 67: 1604589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755951

RESUMO

Objectives: While organ-specific pathophysiology has been well-described in SARS-CoV-2 infection, less is known about the attendant effects on functional status, mood state and leisure-time physical activity (PA) in post-acute COVID-19 syndrome (PASC). Methods: A case-control design was employed to recruit 32 women (n = 17 SARS-CoV-2; n = 15 controls) matched on age (54 ± 12 years) and body mass index (27 ± 6 kg/m2) that did not differ by smoking status or history of cardiopulmonary disease. Participants completed a series of assessments including Profile of Mood States (POMS), Modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-M), and Godin-Shephard Leisure-Time PA. Results: Significant between-group differences were detected for the POMS total mood disturbance with sub-scale analyses revealing elevated tension, confusion, and lower vigor among SARS-CoV-2 participants (all p-values < 0.05). The number of SARS-CoV-2 symptoms (e.g., loss of taste/smell, muscle aches etc.) were associated (r = 0.620, p = 0.008) with confusion. SARS-CoV-2 participants exhibited poorer functional status (p = 0.008) and reduced leisure-time PA (p = 0.004) compared to controls. Conclusion: The sequela of persistent SARS-CoV-2 symptoms elicit clear disturbances in functional status, mood state, and leisure-time PA among women with PASC. Ongoing symptom presentation affects recovery time-course and PA participation.


Assuntos
COVID-19 , Adulto , Idoso , COVID-19/complicações , COVID-19/epidemiologia , Exercício Físico , Feminino , Estado Funcional , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
5.
Obesity (Silver Spring) ; 30(6): 1136-1138, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35352508

RESUMO

Numerous elements of the COVID-19 pandemic have proven challenging to overcome. We now recognize a perplexing characteristic of SARS-CoV-2 features mixed, unresolving symptoms that can last 4 weeks or longer after initial diagnosis, termed post-acute sequelae of SARS-CoV-2 (PASC). Full recovery can thus become a protracted ordeal as conservative estimates indicate 20% of SARS-CoV-2 cases will develop PASC, with women at increased risk. Emerging evidence suggests latent virus reactivation including cytomegalovirus, Epstein-Barr virus, and/or varicella zoster virus may perpetuate the burden of PASC. This is problematic because immune dysfunction is linked to obesity and psychological stress, both of which disproportionately affect socioeconomically disadvantaged people and racial/ethnic minorities. Applying a patient-centered approach in which the principal factors guiding decision-making are based on the needs and abilities of the individual is essential. Still, the independent and combined influence of obesity and psychological stress on immune function necessitates due consideration in the context of PASC recovery.


Assuntos
COVID-19 , Infecções por Vírus Epstein-Barr , Feminino , Herpesvirus Humano 4 , Humanos , Obesidade/complicações , Pandemias , SARS-CoV-2 , Estresse Psicológico
6.
Breast Cancer Res Treat ; 193(2): 467-476, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35347550

RESUMO

PURPOSE: Aging associated with progressive declines in physical function is well-known; however, it is unclear how breast cancer diagnosis affects the trajectories of physical function over a long period of time. The current study examined the trajectories in objective measures of physical function over 20 years for women with breast cancer and matched controls. METHODS: 2712 community-dwelling women (452 breast cancer cases and 1:5 matched cancer-free controls) aged 65 years or older at baseline (1986-1988) within the Study of Osteoporotic Fractures were followed for 20 years. Objective physical function was assessed up to 9 times, including hand grip strength, timed chair stand, gait speed and quadriceps strength. Linear mixed models were used to model physical function changes in terms of secular time trend, group (cases or controls), period (pre-and post-diagnosis status), and their interaction terms. RESULTS: We observed all measures of physical function declined over time. While no differences in trends between cases and controls during the pre-diagnosis period were observed, after cancer diagnosis, grip strength and gait speed declined significantly faster in cases than controls. Quadriceps strength significantly decreased ~ 7 pounds shortly after breast cancer diagnosis, and then improved over time. CONCLUSION: Our study revealed that older breast cancer survivors relative to older women without cancer had significantly worse declines in grip strength and gait speed. Breast cancer survivors also had a sharp, short-term drop followed by gradual improvement over time in quadriceps strength. These findings suggest exercise training targeting muscle strength and mobility would be beneficial among older breast cancer survivors.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Idoso , Feminino , Força da Mão/fisiologia , Humanos , Força Muscular/fisiologia , Velocidade de Caminhada/fisiologia
7.
medRxiv ; 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35043119

RESUMO

OBJECTIVES: While organ-specific pathophysiology has been well-described in SARS-CoV-2 infection, less is known about the attendant effects on functional status, mood state and leisure-time physical activity (PA) in post-acute COVID-19 syndrome. METHODS: A case-control design was employed to recruit 32 women ( n = 17 SARS-CoV-2; n = 15 controls) matched on age (54 ± 12 years), body mass index (27 ± 6 kg/m 2 ), smoking status, and history of cardiopulmonary disease. Participants completed a series of assessments including the Modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-M), Profile of Mood States (POMS), and Godin-Shephard Leisure-Time PA. RESULTS: SARS-CoV-2 participants exhibited poorer functional status ( p = 0.008) and reduced leisure-time PA ( p = 0.004) compared to controls. Significant between-group differences were also detected for the POMS total mood disturbance with sub-scale analyses revealing elevated tension, confusion, and lower vigor among SARS-CoV-2 participants (all p -values < 0.05). The number of SARS-CoV-2 symptoms (e.g., loss of taste / smell, muscle aches etc.) were associated ( r = 0.620, p = 0.008) with confusion. CONCLUSION: The sequela of persistent SARS-CoV-2 symptoms elicit clear disturbances in functional status, mood state, and leisure-time PA among women with post-acute COVID-19 syndrome.

8.
Nitric Oxide ; 118: 39-48, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34774755

RESUMO

Recent reports have acknowledged the underrepresentation of women in the field of dietary nitrate (NO3-) research. Undoubtedly, greater participation from women is warranted to clarify potential sex differences in the responses to dietary NO3- interventions. However, careful consideration for the effects of sex hormones - principally 17ß-estradiol - on endogenous nitric oxide (NO) synthesis and dietary NO3- reductase capacity is necessary for improved interpretation and reproducibility of such investigations. From available literature, we present a narrative review describing how hormonal variations across the menstrual cycle, as well as with menopause, may impact NO biosynthesis catalyzed by NO synthase enzymes and NO3- reduction via the enterosalivary pathway. In doing so, we address methodological considerations related to the menstrual cycle and hormonal contraceptive use relevant for the inclusion of premenopausal women along with factors to consider when testing postmenopausal women. Adherence to such methodological practices may explicate the utility of dietary NO3- supplementation as a means to improve vascular function among women across the lifespan.


Assuntos
Pesquisa Biomédica/métodos , Menopausa/efeitos dos fármacos , Ciclo Menstrual/efeitos dos fármacos , Nitratos/farmacologia , Suplementos Nutricionais , Estradiol/metabolismo , Feminino , Humanos , Menopausa/metabolismo , Ciclo Menstrual/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Fatores Sexuais
9.
Physiol Rep ; 9(20): e15074, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34676680

RESUMO

This study tested the hypotheses that compared to drinking water, consumption of a caffeinated soft drink sweetened with high-fructose corn syrup (HFCS) attenuates the cutaneous vasodilatory response to local skin heating without (Protocol 1) and following ischemia-reperfusion injury (Protocol 2). In a randomized, counterbalanced crossover design, 14 healthy adults (25 ± 3 year, 6 women) consumed 500 ml of water (water) or a caffeinated soft drink sweetened with HFCS (Mtn. Dew, DEW). Thirty minutes following beverage consumption local skin heating commenced on the right forearm (Protocol 1), while on the left forearm ischemia-reperfusion commenced with 20 min of ischemia followed by 20 min of reperfusion and then local skin heating (Protocol 2). Local skin heating involved 40 min of heating to 39℃ followed by 20 min of heating to 44℃. Skin blood flow (SkBf, laser Doppler) data were normalized to mean arterial pressure and are presented as a cutaneous vascular conductance (CVC) and as percentage of the CVC response during heating to 44℃ (%CVCmax ). Protocol 1: During local heating at 39℃, no differences were observed in CVC (water: 2.0 ± 0.6 PU/mmHg; DEW: 2.0 ± 0.8 PU/mmHg, p = 0.83) or %CVCmax (water: 59 ± 14%; DEW 60 ± 15%, p = 0.84) between trials. Protocol 2: During local skin heating at 39℃, no differences were observed in CVC (water: 1.7 ± 0.5 PU/mmHg; DEW: 1.5 ± 0.5 PU/mmHg, p = 0.33) or %CVCmax (water: 64 ± 15%; DEW 61 ± 15% p = 0.62) between trials. The cutaneous microvascular vasodilator response to local heating with or without prior ischemia-reperfusion injury is not affected by acute consumption of a caffeinated soft drink sweetened with HFCS.


Assuntos
Bebidas Gaseificadas/efeitos adversos , Xarope de Milho Rico em Frutose/efeitos adversos , Traumatismo por Reperfusão/patologia , Fenômenos Fisiológicos da Pele , Pele/irrigação sanguínea , Vasodilatação/efeitos dos fármacos , Vasodilatadores/efeitos adversos , Adulto , Feminino , Humanos , Masculino , Microcirculação , Óxido Nítrico/metabolismo , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/etiologia , Pele/efeitos dos fármacos , Pele/patologia , Edulcorantes/efeitos adversos
10.
BMJ Open Sport Exerc Med ; 7(3): e001134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540269

RESUMO

Whether slowing disease progression or combatting the ills of advancing age, the extensive utility of exercise training has contributed to the outright declaration by the American College of Sports Medicine that 'exercise is medicine'. Consistent with general framework of adaptation, the advantages of exercise training are indiscriminate-benefitting even the most susceptible clinical populations. Still, the benefit of exercise training presupposes healthy adaptation wherein progressive overload matches sufficient recovery. Indeed, a difference exists between healthy adaptation and non-functional over-reaching (ie, when internal/external load exceeds recovery capacity)-a difference that may be blurred by cancer treatment and/or comorbidity. Recent advances in smartwatches make them ideally suited to non-invasively monitor the physiological stresses to exercise training. Resolving whether individuals are successfully adapting to exercise training via load monitoring bears clinical and practical relevance. While behaviour-change research aims to identify positive constructs of exercise adherence, further attention is needed to uncover how to optimise exercise prescription among cancer populations. Herein, we briefly discuss the constituents of exercise load monitoring, present examples of internal and external load and consider how such practices can be applied to cancer populations.

11.
Physiol Rep ; 9(7): e14777, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33904664

RESUMO

We tested the hypothesis that ingestion of a caffeinated soft drink sweetened with high-fructose corn syrup acutely increases arterial stiffness. In a randomized counterbalanced, crossover design, fourteen healthy adults (25 ± 3 years, 6 women) reported to the laboratory for two experimental visits where 500 ml of tap water (H2 O) or 500 ml of Mountain Dew® (a caffeinated soft drink sweetened with high-fructose corn syrup (HFCS)) were consumed. Arterial stiffness (carotid-to-femoral pulse wave velocity (cfPWV)), peripheral and central blood pressures were measured pre-consumption, 30 min post-consumption, and 120 min post-consumption. Prior to each measurement period, beat-to-beat hemodynamic measures were collected. Changes in heart rate, blood pressure, and cardiac output from pre-consumption did not differ between trials at any timepoint (p ≥ 0.06). Moreover, changes in peripheral or central blood pressures from pre-consumption did not differ between trials (p ≥ 0.84). Likewise, changes in cfPWV from pre-consumption to 30 min post-consumption (HFCS: 0.2 ± 0.3 m/s, H2 O: 0.0 ± 0.3 m/s, p = 0.34) and 120 min post-consumption (HFCS: 0.3 ± 0.4 m/s, H2 O: 0.2 ± 0.3 m/s, p = 0.77) did not differ. Changes in aortic augmentation pressure, augmentation index, augmentation index corrected to a heart rate of 75 bpm, and reflection magnitude did not differ between conditions at 30 min post- (p ≥ 0.55) or 120 min post- (p ≥ 0.18) consumption. In healthy young adults, ingesting 500 ml of a commercially available caffeinated soft drink sweetened with high-fructose corn syrup does not acutely change indices of arterial stiffness and wave reflection.


Assuntos
Cafeína/farmacologia , Xarope de Milho Rico em Frutose/farmacologia , Rigidez Vascular/efeitos dos fármacos , Adulto , Cafeína/administração & dosagem , Bebidas Gaseificadas , Feminino , Hemodinâmica/efeitos dos fármacos , Xarope de Milho Rico em Frutose/administração & dosagem , Humanos , Masculino
12.
Obesity (Silver Spring) ; 28(7): 1176-1177, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32299148

RESUMO

As the biomedical community races to disentangle the unknowns associated with severe acute respiratory syndrome coronavirus 2, the virus responsible for causing coronavirus disease, the link between diminished immune function and individuals with obesity raises important questions about the possibility for greater viral pathogenicity in this population. Increased adiposity may undermine the pulmonary microenvironment wherein viral pathogenesis and immune cell trafficking could contribute to a maladaptive cycle of local inflammation and secondary injury. A further challenge to those with obesity during the current pandemic may involve vitamin D deficiency or insufficiency. In the interest of personal and public health, we caution decision- and policy makers alike not to pin all hope on a proverbial "silver bullet." Until further breakthroughs emerge, we should remember that modifiable lifestyle factors such as diet and physical activity should not be marginalized. Decades of empirical evidence support both as key factors promoting health and wellness.


Assuntos
Betacoronavirus , Infecções por Coronavirus/virologia , Exercício Físico , Obesidade/virologia , Pneumonia Viral/virologia , Deficiência de Vitamina D/virologia , COVID-19 , Dieta/efeitos adversos , Humanos , Inflamação , Estilo de Vida , Estado Nutricional , Obesidade/sangue , Obesidade/fisiopatologia , Pandemias , SARS-CoV-2 , Vitamina D/sangue
13.
Prev Med ; 132: 105989, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31954141

RESUMO

It is unclear how resting myocardial workload, as indexed by baseline measures of rate-pressure product (RPP) and physical activity (PA), is associated with the overall risk of cancer mortality. We performed prospective analyses among 28,810 men and women from the REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort. We used a novel physical health (PH) composite index and categorized participants into one of four groups based on combinations from self-reported PA and RPP: 1) No PA and High RPP; 2) No PA and Low RPP; 3) Yes PA and High RPP; and 4) Yes PA and Low RPP. We examined the association between baseline PH composite and cancer mortality adjusted for potential confounders using Cox regression. A total of 1191 cancer deaths were observed over the 10-year observation period, with the majority being lung (26.87%) and gastrointestinal (21.49%) cancers. Even after controlling for sociodemographics, health behaviors, baseline comorbidity score, and medications, participants with No PA and High RPP had 71% greater risk of cancer mortality when compared to participants with PA and Low RPP (adjusted HR: 1.71, 95% CI: 1.42-2.06). These associations persisted after examining BMI, smoking, income, and gender as effect modifiers and all-cause mortality as a competing risk. Poorer physical health composite, including the novel RPP metric, was associated with a nearly 2-fold long-term risk of cancer mortality. The physical health composite has important public health implications as it provides a measure of risk beyond traditional measure of obesity and physical activity.


Assuntos
Exercício Físico , Comportamentos Relacionados com a Saúde/fisiologia , Nível de Saúde , Neoplasias/mortalidade , Idoso , Comorbidade , Feminino , Frequência Cardíaca/fisiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neoplasias/etnologia , Estudos Prospectivos , Autorrelato
14.
Eur J Appl Physiol ; 119(11-12): 2457-2464, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520215

RESUMO

PURPOSE: With accelerometry, the utility to detect changes in physical activity are predicated on the assumption that walking energetics and gait mechanics do not change. The present work examined associations between changes (∆) in walking energetics, exercise self-efficacy, and several accelerometer-derived metrics. METHODS: Secondary analyses were performed among a sub-sample (n = 29) of breast cancer survivors participating in a larger randomized trial. During 4 min of treadmill walking (0.89 m s-1, 0% grade), indirect calorimetry quantified steady-state energy expenditure (EE), wherein, participants were fitted with a heart rate monitor and hip-worn triaxial accelerometer. Exercise self-efficacy was measured using a 9-item questionnaire, while vector magnitude (VM) and individual planes (e.g., mediolateral, vertical, and anteroposterior) of the movement were extracted for data analyses. Evaluations were made at baseline and after 3 months. RESULTS: From baseline to 3 months, the energetic cost of walking (kcals min-1) significantly decreased by an average of - 5.1% (p = 0.001; d = 0.46). Conversely, VM significantly increased (p = 0.007; d = 0.53), exclusively due to greater vertical accelerations (acc) (+ 5.7 ± 7.8 acc; p = 0.001; d = 0.69). Changes in vertical accelerations were inversely and positively associated with ∆walking EE (r = - 0.37; p = 0.047) and ∆exercise self-efficacy (r = 0.39; p = 0.034), respectively. CONCLUSION: Hip-worn accelerometers do not appear well-suited to correctly detect changes in ease of walking as evidenced by reduced energetic cost. Further research should determine if a divergence between measured EE and vertical accelerations could contribute to erroneous inferences in free-living physical activity.


Assuntos
Neoplasias da Mama/fisiopatologia , Metabolismo Energético/fisiologia , Caminhada/fisiologia , Aceleração , Acelerometria/métodos , Sobreviventes de Câncer , Exercício Físico/fisiologia , Teste de Esforço/métodos , Feminino , Marcha/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Pessoa de Meia-Idade , Atividade Motora/fisiologia
15.
Exp Physiol ; 104(4): 529-539, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30763983

RESUMO

NEW FINDINGS: What is the central question of this study? Does the link between cardiorespiratory fitness and gut microbiota diversity persist after adjusting for the potential effects of percentage body fat and activity-related energy expenditure (AEE)? What is the main finding and its importance? This is the first study to examine the link between cardiorespiratory fitness and gut microbiota diversity while accounting for the underlying effects of percentage body fat and free-living AEE. Results from the present work suggest that cardiorespiratory fitness, not physical activity, is a superior correlate of gut microbiota diversity among post-primary treatment, non-metastatic breast cancer survivors. ABSTRACT: Cancer treatment uniquely triggers multiple physiological shifts detrimental to overall health. Although previous research indicates a link between the gut microbiota and cardiorespiratory fitness, it is unclear whether these findings are attributable to potential underlying effects of percentage body fat or free-living activity energy expenditure (AEE). The microbe composition of faecal specimens from 37 breast cancer survivors was determined using 16S microbiome analyses. Individual-sample microbiota diversity (α-diversity) and between-sample community differences (ß-diversity) were examined. Peak oxygen uptake ( V̇O2peak ) was estimated from a graded exercise test consistent with the modified Naughton protocol, in which exercise terminates at 85% of age-predicted maximal heart rate. The AEE was measured over 10 days using doubly labelled water, wherein the percentage body fat was calculated from total body water. Pearson correlations revealed α-diversity indices (Chao1, observed species, PD whole tree and Shannon) to be positively associated with V̇O2peak (r = 0.34-0.51; P < 0.05), whereas the percentage of maximal heart rate during stages 1-4 of the graded exercise test (r = -0.34 to -0.50; P < 0.05) and percentage body fat (r = -0.32 to -0.41; P < 0.05) were negatively associated with the same α-diversity indices. Multiple linear regression models showed that V̇O2peak accounted for 22 and 26% of the variance in taxonomic richness (observed species) and phylogenic diversity after adjustment for percentage body fat and menopausal status. Unweighted UniFrac (ß-diversity) was significant for several outcomes involving cardiorespiratory fitness, and significant taxa comparisons were found. Associations between gut microbiota and free-living AEE were not found. Results from the present work suggest that cardiorespiratory fitness, not physical activity, is a superior correlate of gut microbiota diversity.


Assuntos
Neoplasias da Mama/microbiologia , Neoplasias da Mama/fisiopatologia , Aptidão Cardiorrespiratória/fisiologia , Microbioma Gastrointestinal/fisiologia , Aptidão Física/fisiologia , Composição Corporal/fisiologia , Metabolismo Energético/fisiologia , Teste de Esforço/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Sobreviventes
16.
Int J Exerc Sci ; 11(2): 42-54, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29795723

RESUMO

The functional implications of serum tumor necrosis factor-alpha (TNF-α), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-α on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-α on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO2max). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index of myocardial oxygen demand, was measured at rest and during two submaximal workloads (i.e., ≈55% and ≈75% VO2max). RPP was calculated by dividing the product of heart rate and systolic blood pressure (via auscultation) by 100. Exercise tolerance corresponded with the cessation of the graded exercise test. During higher-intensity exertion, ≈75% VO2max, multiple linear regression revealed a positive association (r = 0.43; p = 0.015) between TNF-α and RPP while adjusting for maximal heart rate, VO2max, large artery compliance, and percent body fat. Path analyses revealed a significant indirect effect of large artery compliance on exercise tolerance through TNF-α, ß = 0.13, CI [0.03, 0.35], indicating greater levels of TNF-α associated with poorer exercise tolerance. These data suggest TNF-α independently associates with myocardial oxygen demand during physical exertion, thus highlighting the utility of higher-intensity efforts to expose important phenomena not apparent at rest. TNF-α also appears to be indirectly associated with the link between large artery compliance and exercise tolerance.

17.
Clin Nutr ; 37(1): 56-60, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28214041

RESUMO

Age-related declines in health and function make locomotion increasingly difficult leading to reductions in non-exercise activity thermogenesis (NEAT), skeletal muscle size and strength, and increased adiposity. Exercise is an important strategy to attenuate loss of function through the life cycle. Despite claims to the contrary, high-intensity exercise is important for the prevention of obesity and sarcopenia with advancing age. Therefore, the purpose of this mini-review is to present literature supporting the contention that low volume, high-intensity aerobic and/or resistance training can slow sarcopenia, sustain ease of movement, stimulate NEAT, and attenuate the accretion of fat mass.


Assuntos
Exercício Físico , Comportamentos Relacionados com a Saúde , Nível de Saúde , Treinamento Resistido , Adulto , Idoso , Idoso de 80 Anos ou mais , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/prevenção & controle , Sarcopenia/prevenção & controle
18.
Support Care Cancer ; 26(5): 1675-1683, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29243165

RESUMO

PURPOSE: We hypothesized exercise training-induced improvements in ease of walking would associate with favorable changes in objectively measured physical activity (PA) and self-reported depressive symptoms following a PA behavior-change intervention in non-metastatic breast cancer survivors (BCS). METHODS: Twenty-seven BCS received random assignment to an intervention (INT) or control group (CON). INT included counseling/group discussions coupled with supervised exercise tapered to unsupervised exercise. PA, depressive symptoms, and ease of walking were evaluated pre-/post-intervention using 10-day accelerometry, HADS depression subscale, and indirect calorimetry during a standardized treadmill test, respectively. PA composite score was calculated by converting weekly minutes of moderate-to-vigorous PA and average steps/day to z-scores then dividing the sum by 2. Cardiac efficiency was determined by dividing steady-state oxygen uptake by heart rate to evaluate the volume of oxygen consumed per heartbeat. RESULTS: ANCOVA revealed a significant time by group interaction showing the INT group exhibited greater positive changes in the PA composite compared to the CON (INT, + 0.14 ± 0.66 au vs. CON, - 0.48 ± 0.49 au; p = 0.019; η p2 = 0.21). Changes occurring from baseline to follow-up, among all participants, revealed improved ease of walking (less oxygen uptake) associated with increased PA composite (r = - 0.52; p = 0.010) and lower depressive symptomology (r = 0.50; p = 0.012) adjusted for age, race, and months since cancer diagnosis. Increased cardiac efficiency during the standardized treadmill test also associated with less daily sedentary time (r = - 0.52; p = 0.021). CONCLUSIONS: These data support the assertion that reducing the physiological difficulty of walking may contribute to greater engagement in free-living PA, less sedentary time, and decreased psychosocial distress among BCS.


Assuntos
Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Depressão/psicologia , Exercício Físico/psicologia , Qualidade de Vida/psicologia , Caminhada/psicologia , Adolescente , Adulto , Idoso , Exercício Físico/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Caminhada/fisiologia , Adulto Jovem
19.
Support Care Cancer ; 25(5): 1563-1570, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28064384

RESUMO

PURPOSE: In this proof-of-concept pilot study, our purpose was to determine correlations between gut microbiota composition and alterations in cardiorespiratory fitness and psychosocial outcomes among post-primary treatment breast cancer survivors (BCS). METHODS: Composition of the gut microbiota in BCS (n = 12) was assessed at baseline (M0) and at the end of 3 months (M3) using Illumina MiSeq DNA Sequencing of the 16S rRNA gene. Gut microbiota composition was analyzed using the QIIME bioinformatics software and represented through diversity metrics and taxa analyses. Cardiorespiratory fitness, fatigue, anxiety, depression, and sleep dysfunction were assessed at M0 and M3 via the submaximal treadmill test, Fatigue Symptom Inventory, Hospital Anxiety and Depression Scale, and Pittsburgh Sleep Quality Index, respectively. RESULTS: Increased fatigue interference in BCS was associated with increased mean within-sample Shannon diversity (organism richness and evenness) (p = 0.009). Weighted UniFrac analysis (shifts in taxa relative abundance) revealed significant differences in between-sample (beta) diversity for changes in fatigue interference (p = 0.01) and anxiety (p = 0.022), with a trend observed for fatigue intensity and sleep dysfunction (p < 0.1). Unweighted UniFrac analysis (shifts in taxa types) found significant beta diversity differences for cardiorespiratory fitness (p = 0.026). Prior to false discovery correction (FDR), changes in fitness, fatigue, anxiety, and sleep dysfunction were associated with the frequency of certain gut bacteria genera (e.g., Faecalibacterium, Prevotella, Bacteroides) (p < 0.05). CONCLUSIONS: Correlations may exist between alterations in gut microbiota composition and longitudinal changes in cardiorespiratory fitness, fatigue, and anxiety in BCS. Further research examining the role of the microbiota-gut-brain axis in exercise-induced effects on psychosocial outcomes in BCS is warranted.


Assuntos
Neoplasias da Mama/psicologia , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Microbioma Gastrointestinal/imunologia , Adolescente , Adulto , Idoso , Neoplasias da Mama/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Taxa de Sobrevida , Sobreviventes/psicologia , Adulto Jovem
20.
Breast Cancer Res Treat ; 159(2): 283-91, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27539586

RESUMO

Little is known about the effects of physical activity behavior change interventions on health outcomes such as lower extremity dysfunction and SF-36 physical health (predictor of mortality) in breast cancer survivors. Furthermore, effect moderators are rarely reported. Therefore, we report the effects of the 3-month BEAT Cancer physical activity behavior change intervention on global health status and health indicators along with moderators of intervention outcomes. Postprimary treatment breast cancer survivors (n = 222) were randomized to BEAT Cancer or usual care (UC). SF-36, muscle strength, body mass index, lower extremity dysfunction (WOMAC), and life satisfaction were measured at 3 months (M3) and 6 months (M6). At M3, adjusted linear mixed-model analyses demonstrated statistically significant effects of BEAT Cancer versus UC on SF-36 physical health [mean between-group difference (M) = 2.1; 95 % confidence interval (CI) 0.3-3.9; p = 0.023], SF-36 mental health (M = 5.2; CI 2.8-7.6; p < 0.001), and all SF-36 subscores. Intervention benefits occurred for lower extremity physical dysfunction (M = -2.7; CI -5.0 to -0.5; p = 0.018), WOMAC total (M = -3.7; CI -6.7 to -0.6; p = 0.018), and life satisfaction (M = 2.4; CI 0.9-3.9; p = 0.001). Statistically significant effects persisted at M6 for mental health and vitality. Baseline value, income, marital status, cancer treatment, cancer stage, and months since diagnosis moderated one or more outcomes. BEAT Cancer improves SF-36, WOMAC, and life satisfaction outcomes with improvements in vitality and mental well-being continuing 3 months postintervention. Several moderators with potential to guide targeting individuals for optimal intervention benefit warrant further study.


Assuntos
Neoplasias da Mama/terapia , Sobreviventes de Câncer/psicologia , Exercício Físico/fisiologia , Adulto , Idoso , Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/psicologia , Feminino , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Força Muscular , Músculo Esquelético/fisiologia , Cooperação do Paciente , Qualidade de Vida/psicologia , Adulto Jovem
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