Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Annu Rev Med ; 73: 377-391, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34794323

RESUMO

The global population is rapidly aging, with predictions of many more people living beyond 85 years. Age-related physiological adaptations predispose to decrements in physical function and functional capacity, the rate of which can be accelerated by chronic disease and prolonged physical inactivity. Decrements in physical function exacerbate the risk of chronic disease, disability, dependency, and frailty with advancing age. Regular exercise positively influences health status, physical function, and disease risk in adults of all ages. Herein, we review the role of structured exercise training in the oldest old on cardiorespiratory fitness and muscular strength and power, attributes critical for physical function, mobility, and independent living.


Assuntos
Exercício Físico , Octogenários , Adulto , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Terapia por Exercício , Humanos , Força Muscular/fisiologia
2.
J Strength Cond Res ; 37(11): e601-e608, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37883408

RESUMO

ABSTRACT: Redshaw, AS, Carrick-Ranson, G, Bennett, H, Norton, KI, and Walker, A. Effect of aging on movement quality in Australian urban firefighters. J Strength Cond Res 37(11): e601-e608, 2023-Adequate levels of movement quality (MQ) are required to safely perform occupational tasks in physically demanding and hazardous professions such as firefighting. Although it is well established that MQ deteriorates with age in population studies, there is conflicting evidence in older tactical populations. This study sought to examine the relationship between age and MQ in Australian urban firefighters. The impact of physical activity, injury history, and body mass index on MQ were also explored. The MQ of 324 professional Australian urban firefighters was assessed using MovementSCREEN MQ assessment tool. Scores of whole-body MQ ranged from 35.3 to 82.6 (0-100 scale), with a mean score of 59.2 ± 10.0. There was a moderate, negative association between MQ and age (r = -0.500; p ≤ 0.001), with those older than 50 years of age having significantly lower scores of MQ than their younger counterparts (p ≤ 0.001). Secondary analysis found that higher body mass index (r = -0.285; p ≤ 0.001), lower habitual physical activity levels (r = 0.165; p ≤ 0.003), and the presence of any musculoskeletal injury in the previous 12 months (p = 0.016) had significant negative effects on composite MQ. Firefighters older than 50, obese, and engaging in low levels of physical activity should be considered a high priority for functional strength training interventions to maintain adequate MQ throughout their careers.


Assuntos
Bombeiros , Treinamento Resistido , Humanos , Idoso , Austrália , Envelhecimento , Índice de Massa Corporal , Movimento
3.
J Physiol ; 598(13): 2589-2605, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32347540

RESUMO

KEY POINTS: The beneficial effects of sustained or lifelong (>25 years) endurance exercise on cardiovascular structure and exercise function have been largely established in men. The current findings indicate that committed (≥4 weekly exercise sessions) lifelong exercise results in substantial benefits in exercise capacity ( V̇O2max ), cardiovascular function at submaximal and maximal exercise, left ventricular mass and compliance, and blood volume compared to similarly aged or even younger (middle-age) untrained women. Endurance exercise training should be considered a key strategy to prevent cardiovascular disease with ageing in women as well as men. ABSTRACT: This study was a retrospective, cross-sectional analysis of exercise performance and left ventricular (LV) morphology in 70 women to examine whether women who have performed regular, lifelong endurance exercise acquire the same beneficial adaptations in cardiovascular structure and function and exercise performance that have been reported previously in men. Three groups of women were examined: (1) 35 older (>60 years) untrained women (older untrained, OU), (2) 13 older women who had consistently performed four or more endurance exercise sessions weekly for at least 25 years (older trained, OT), and (3) 22 middle-aged (range 35-59 years) untrained women (middle-aged untrained, MU) as a reference control for the appropriate age-related changes. Oxygen uptake ( V̇O2 ) and cardiovascular function (cardiac output ( Q̇ ); stroke volume (SV) acetylene rebreathing) were examined at rest, steady-state submaximal exercise and maximal exercise (maximal oxygen uptake, V̇O2max ). Blood volume (CO rebreathing) and LV mass (cardiac magnetic resonance imaging), plus invasive measures of static and dynamic chamber compliance were also examined. V̇O2max (p < 0.001) and maximal exercise Q̇ and SV were larger in older trained women compared to the two untrained groups (∼17% and ∼27% for Q̇ and SV, respectively, versus MU; ∼40% and ∼38% versus OU, all p < 0.001). Blood volume (mL kg-1 ) and LV mass index (g m-2 ) were larger in OT versus OU (∼11% and ∼16%, respectively, both P ≤ 0.015) Static LV chamber compliance was greater in OT compared to both untrained groups (median (25-75%): MU: 0.065 (0.049-0.080); OU: 0.085 (0.061-0.138); OT: 0.047 (0.031-0.054), P ≤ 0.053). Collectively, these findings indicate that lifetime endurance exercise appears to be extremely effective at preserving or even enhancing cardiovascular structure and function with advanced age in women.


Assuntos
Resistência Física , Função Ventricular Esquerda , Adulto , Idoso , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Estudos Retrospectivos , Volume Sistólico
4.
J Physiol ; 596(14): 2783-2795, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781119

RESUMO

KEY POINTS: This study examined the effect of different 'doses' of lifelong (>25 years) exercise on arterial stiffening (a hallmark of vascular ageing) in older adults. There are clear dose-dependent effects of lifelong exercise training on human arterial stiffness that vary according to the site and size of the arteries. Similar to what we have observed previously with ventricular stiffening, 4-5 days week-1 of committed exercise over a lifetime are necessary to preserve 'youthful' vascular compliance, especially of the large central arteries. Casual exercise training of two to three times per week may be sufficient for middle-sized arteries like the carotid to minimize arterial stiffening with ageing. However, there is little effect of exercise training on the small-sized peripheral arteries at any dose. ABSTRACT: Central arterial stiffness increases with sedentary ageing. While near-daily, vigorous lifelong (>25 years) endurance exercise training prevents arterial stiffening with ageing, this rigorous routine of exercise training over a lifetime is impractical for most individuals. The aim was to examine whether a less frequent 'dose' of lifelong exercise training (four to five sessions per week for > 30 min) that is consistent with current physical activity recommendations elicits similar benefits on central arterial stiffening with ageing. A cross-sectional examination of 102 seniors (>60 years old) who had a consistent lifelong exercise history was performed. Subjects were stratified into four groups based on exercise frequency as an index of exercise 'dose': sedentary: fewer than two sessions per week; casual exercisers: two to three sessions per week; committed exercisers: four to five sessions per week; and Masters athletes: six to seven sessions per week plus regular competitions. Detailed measurements of arterial stiffness and left ventricular afterload were collected. Biological aortic age and central pulse wave velocity were younger in committed exercisers and Masters athletes compared to sedentary seniors. Total arterial compliance index (TACi) was lower, while carotid ß-stiffness index and effective arterial elastance were higher in sedentary seniors compared to the other groups. There appeared to be a dose-response threshold for carotid ß-stiffness index and TACi. Peripheral arterial stiffness was not significantly different among the groups. These data suggest that four to five weekly exercise sessions over a lifetime is associated with reduced central arterial stiffness in the elderly. A less frequent dose of lifelong exercise (two to three sessions per week) is associated with decreased ventricular afterload and peripheral resistance, while peripheral arterial stiffness is unaffected by any dose of exercise.


Assuntos
Artérias/fisiopatologia , Exercício Físico , Resistência Vascular , Rigidez Vascular , Função Ventricular Esquerda , Idoso , Envelhecimento , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Física , Análise de Onda de Pulso
5.
Qual Life Res ; 27(4): 993-998, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29350344

RESUMO

PURPOSE: To quantify the relationship between the change in exercise dose and health-related quality of life (HRQoL) in a cohort of patients participating in a community-based phase-3 cardiac rehabilitation (CR) program. METHODS: A retrospective, pre-experimental (no control group) design of 58 participants that completed a phase-3, 12-week exercise-based CR program was used to test the current hypothesis. Self-reported HRQoL (36-Item Short Form Health Survey Version 2, SF-36v2) was assessed prior and after completing the CR program. The change in exercise dose was estimated from the assigned training load in weeks 1 and 12 of the CR program. A series of regression models were fitted to ascertain the relationship between the change in exercise dose and changes in the SF-36v2. RESULTS: There was a strong quadratic trend between the change in exercise dose and the mean change in SF-36 Mental and Physical Health Summary Scores. Analysis of covariance showed that the mean changes in the SF-36 Summary Scores statistically fluctuate across quartiles of exercise dose. The data show that there is a threshold amount of increase in exercise (Q2; 350-510 kcal week- 1) needed to HRQoL and that greater amounts of exercise dose (Q3; 511-687 and Q4 ≥ 688 kcal week- 1) did not improve HRQoL further. CONCLUSIONS: The current findings suggest that physical and mental health-related quality of life are improved with a phase-3 CR program. The dose-response relationship observed indicates that a threshold exercise dose is required to improve HRQoL, and that larger doses of exercise do not confer further improvements in HRQoL.


Assuntos
Reabilitação Cardíaca/métodos , Metabolismo Energético/fisiologia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Qualidade de Vida/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Circulation ; 127(1): 55-62, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23172838

RESUMO

BACKGROUND: Hemodynamic assessment after volume challenge has been proposed as a way to identify heart failure with preserved ejection fraction. However, the normal hemodynamic response to a volume challenge and how age and sex affect this relationship remain unknown. METHODS AND RESULTS: Sixty healthy subjects underwent right heart catheterization to measure age- and sex-related normative responses of pulmonary capillary wedge pressure and mean pulmonary arterial pressure to volume loading with rapid saline infusion (100-200 mL/min). Hemodynamic responses to saline infusion in heart failure with preserved ejection fraction (n=11) were then compared with those of healthy young (<50 years of age) and older (≥50 years of age) subjects. In healthy subjects, pulmonary capillary wedge pressure increased from 10±2 to 16±3 mm Hg after ~1 L and to 20±3 mm Hg after ~2 L of saline infusion. Older women displayed a steeper increase in pulmonary capillary wedge pressure relative to volume infused (16±4 mm Hg·L(-1)·m(2)) than the other 3 groups (P≤0.019). Saline infusion resulted in a greater increase in mean pulmonary arterial pressure relative to cardiac output in women compared with men regardless of age. Subjects with heart failure with preserved ejection fraction exhibited a steeper increase in pulmonary capillary wedge pressure relative to infused volume (25±12 mm Hg·L(-1)·m(2)) than healthy young and older subjects (P≤0.005). CONCLUSIONS: Filling pressures rise significantly with volume loading, even in healthy volunteers. Older women and patients with heart failure with preserved ejection fraction exhibit the largest increases in pulmonary capillary wedge pressure and mean pulmonary arterial pressure.


Assuntos
Técnicas de Diagnóstico Cardiovascular/normas , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Cloreto de Sódio/administração & dosagem , Adulto , Fatores Etários , Idoso , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pressão Propulsora Pulmonar/fisiologia , Valores de Referência , Caracteres Sexuais , Fatores Sexuais , Volume Sistólico/fisiologia , Pressão Ventricular/fisiologia , Adulto Jovem
7.
Work ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552128

RESUMO

BACKGROUND: Firefighting is recognised as a physically demanding occupation involving exposure to hazardous environments and activities. An aging workforce combined with the age-related decline in physical fitness may result in increased future workers' compensation expenditure for fire service organisations. OBJECTIVE: The objective of this research was to investigate the costs associated with musculoskeletal sprain and strain injury and the impacts of age and injury location on Workers' Compensation claims submitted by professional urban firefighters. METHODS: Claim rates, direct costs, and days lost were extracted from a professional Fire Service organisation's workers' compensation claim database for financial years between 2011 to 2018. RESULTS: The mean cost per claim increased with age, with a mean claim cost of the 60-70-year-old group over 10 times more than the 20-29-year-old group. The mean days lost per claim were also higher for claims submitted by firefighters aged over 50. CONCLUSIONS: Older firefighters miss more workdays when injured and are associated with increased claims costs, particularly those in the 60-70-year group. With an aging workforce, Fire Service organisations must implement appropriate management and prevention strategies to reduce the potential risks associated with an aging workforce.

8.
Exp Physiol ; 98(2): 501-13, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23002243

RESUMO

A marked reduction in upright stroke volume (SV) contributes substantially to orthostatic intolerance after exposure to spaceflight or bed rest. It is unclear whether slowed left ventricular (LV) relaxation and diastolic suction contribute to the reduction in SV or whether these changes are influenced by exercise training while in bed. Twenty-seven healthy adults completed 5 weeks of -6 deg head-down bed rest (HDBR). During HDBR, nine subjects were sedentary (NOEX), while 18 performed near-daily rowing ergometry (EX). Left ventricular mass, SV, LV end-diastolic volume (LVEDV), pulmonary capillary wedge pressure and Doppler ultrasound indices of LV function were collected pre- and post-HDBR during supine rest (twice) and during reduced LV loading (lower body negative pressure; LBNP) and increased LV loading (saline infusion). Post-HDBR, LV mass increased in the EX group, but decreased in the NOEX group. The reduction in SV and LVEDV during supine rest and LBNP were greater with NOEX in comparison to EX after HDBR. Peak early mitral annular velocity, isovolumic relaxation time, early propagation velocity, a non-invasive index of early diastolic filling and ventricular diastolic suction, and peak global longitudinal early strain rate were slowed during supine rest after HDBR with NOEX; however, these variables were either unaltered or the reduction was less prominent with EX. Doppler ultrasound measures of early diastolic filling, ventricular relaxation and diastolic suction were not significantly affected during LV unloading by LBNP after HDBR in either group. All Doppler indices were restored to pre-HDBR levels in both groups during saline infusion to normalize LV filling pressure after HDBR. It is concluded that Doppler indices of dynamic LV filling were reduced in both groups after HDBR; however, these effects were more pronounced in the NOEX group. Irrespective of group, post-HDBR Doppler parameters were restored when LV filling pressure was increased to pre-HDBR levels during saline infusion. Therefore, the reduction in upright SV after HDBR is more influenced by changes in LV loading conditions, namely left atrial pressure in the setting of LV remodelling, rather than ventricular relaxation and diastolic suction.


Assuntos
Repouso em Cama/efeitos adversos , Diástole , Intolerância Ortostática/prevenção & controle , Treinamento Resistido , Descanso , Função Ventricular Esquerda , Adulto , Análise de Variância , Ecocardiografia Doppler , Feminino , Decúbito Inclinado com Rebaixamento da Cabeça , Humanos , Infusões Intravenosas , Pressão Negativa da Região Corporal Inferior , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Intolerância Ortostática/diagnóstico por imagem , Intolerância Ortostática/etiologia , Intolerância Ortostática/fisiopatologia , Pressão Propulsora Pulmonar , Cloreto de Sódio/administração & dosagem , Volume Sistólico , Decúbito Dorsal , Texas , Fatores de Tempo , Adulto Jovem
9.
J Appl Physiol (1985) ; 135(6): 1215-1235, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855034

RESUMO

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality in women in developed societies. Unfavorable structural and functional adaptations within the heart and central blood vessels with sedentary aging in women can act as the substrate for the development of debilitating CVD conditions such as heart failure with preserved ejection fraction (HFpEF). The large decline in cardiorespiratory fitness, as indicated by maximal or peak oxygen uptake (V̇o2max and V̇o2peak, respectively), that occurs in women as they age significantly affects their health and chronic disease status, as well as the risk of cardiovascular and all-cause mortality. Midlife and older women who have performed structured endurance exercise training for several years or decades of their adult lives exhibit a V̇o2max and cardiac and vascular structure and function that are on par or even superior to much younger sedentary women. Therefore, regular endurance exercise training appears to be an effective preventative strategy for mitigating the adverse physiological cardiovascular adaptations associated with sedentary aging in women. Herein, we narratively describe the aging and short- and long-term endurance exercise training adaptations in V̇o2max, cardiac structure, and left ventricular systolic and diastolic function at rest and exercise in midlife and older women. The role of circulating estrogens on cardiac structure and function is described for consideration in the timing of exercise interventions to maximize beneficial adaptations. Current research gaps and potential areas for future investigation to advance our understanding in this critical knowledge area are highlighted.


Assuntos
Aptidão Cardiorrespiratória , Insuficiência Cardíaca , Adulto , Humanos , Feminino , Idoso , Volume Sistólico/fisiologia , Envelhecimento/fisiologia , Exercício Físico/fisiologia , Resistência Física , Consumo de Oxigênio/fisiologia , Função Ventricular Esquerda/fisiologia
10.
J Physiol ; 590(8): 1871-80, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22331419

RESUMO

Healthy, but sedentary ageing leads to marked atrophy and stiffening of the heart, with substantially reduced cardiac compliance; but the time course of when this process occurs during normal ageing is unknown. Seventy healthy sedentary subjects (39 female; 21­77 years) were recruited from the Dallas Heart Study, a population-based, random community sample and enriched by a second random sample from employees of Texas Health Resources. Subjects were highly screened for co-morbidities and stratified into four groups according to age: G(21−34): 21­34 years, G(35−49): 35­49 years, G5(0−64): 50­64 years, G(≥65): ≥65 years. All subjects underwent invasive haemodynamic measurements with right heart catheterization to define Starling and left ventricular (LV) pressure­volume curves. LV end-diastolic volumes (EDV) were measured by echocardiography at baseline, −15 and −30 mmHg lower-body negative pressure, and 15 and 30 ml kg(−1) saline infusion with simultaneous measurements of pulmonary capillary wedge pressure. There were no differences in heart rate or blood pressures among the four groups at baseline. Baseline EDV index was smaller in G(≥65) than other groups. LV diastolic pressure­volume curves confirmed a substantially greater LV compliance in G(21−34) compared with G(50−64) and G(≥65), resulting in greater LV volume changes with preload manipulations. Although LV chamber compliance in G(50−64) and G(≥65) appeared identical, pressure­volume curves were shifted leftward, toward a decreased distensibility, with increasing age. These results suggest that LV stiffening in healthy ageing occurs during the transition between youth and middle-age and becomes manifest between the ages of 50 to 64. Thereafter, this LV stiffening is followed by LV volume contraction and remodelling after the age of 65.


Assuntos
Envelhecimento/fisiologia , Coração/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Cateterismo Cardíaco/métodos , Estudos de Coortes , Complacência (Medida de Distensibilidade)/fisiologia , Diástole/fisiologia , Ecocardiografia/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Propulsora Pulmonar/fisiologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto Jovem
11.
Am J Physiol Heart Circ Physiol ; 303(3): H315-22, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22661507

RESUMO

Doppler ultrasound measures of left ventricular (LV) active relaxation and diastolic suction are slowed with healthy aging. It is unclear to what extent these changes are related to alterations in intrinsic LV properties and/or cardiovascular loading conditions. Seventy carefully screened individuals (38 female, 32 male) aged 21-77 were recruited into four age groups (young: <35; early middle age: 35-49; late middle age: 50-64 and seniors: ≥65 yr). Pulmonary capillary wedge pressure (PCWP), stroke volume, LV end-diastolic volume, and Doppler measures of LV diastolic filling were collected at multiple loading conditions, including supine baseline, lower body negative pressure to reduce LV filling, and saline infusion to increase LV filling. LV mass, supine PCWP, and heart rate were not affected significantly by aging. Measures of LV relaxation, including isovolumic relaxation time and the time constant of isovolumic pressure decay increased progressively, whereas peak early mitral annular longitudinal velocity decreased with advancing age (P < 0.001). The propagation velocity of early mitral inflow, a noninvasive measure of LV suction, decreased with aging with the greatest reduction in seniors (P < 0.001). Age-related differences in LV relaxation and diastolic suction were not attenuated significantly when PCWP was increased in older subjects or reduced in the younger subjects. There is an early slowing of LV relaxation and diastolic suction beginning in early middle age, with the greatest reduction observed in seniors. Because age-related differences in LV dynamic diastolic filling parameters were not diminished significantly with significant changes in LV loading conditions, a decline in ventricular relaxation is likely responsible for the alterations in LV diastolic filling with senescence.


Assuntos
Envelhecimento/fisiologia , Diástole , Função Ventricular Esquerda , Adulto , Fatores Etários , Idoso , Análise de Variância , Cateterismo Cardíaco , Ecocardiografia Doppler , Feminino , Frequência Cardíaca , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Propulsora Pulmonar , Volume Sistólico , Sístole , Texas , Adulto Jovem
12.
Am J Physiol Heart Circ Physiol ; 300(5): H1688-95, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21398598

RESUMO

Pericardial constraint and ventricular interaction influence left ventricular (LV) performance when preload is high. However, it is unclear if these constraining forces modulate LV filling when the heart is unloaded, such as during upright posture, in humans. Fifty healthy individuals underwent right heart catheterization to measure pulmonary capillary wedge (PCWP) and right atrial pressure (RAP). To evaluate the effects of pericardial constraint on hemodynamics, transmural filling pressure (LVTMP) was defined as PCWP-RAP. Beat-to-beat blood pressure (BP) waveforms were recorded, and stroke volume (SV) was derived from the Modelflow method. After measurements at -30 mmHg lower body negative pressure (LBNP), which approximates the upright position, LBNP was released, and beat-to-beat measurements were performed for 15 heartbeats. At -30 mmHg LBNP, RAP and PCWP were significantly decreased. During the first six beats of LBNP release, heart rate (HR) was unchanged, while BP increased from the fourth beat. RAP increased faster than PCWP resulting in an acute decrease in LVTMP from the fourth beat. A corresponding drop in SV by 3% was observed with no change in pulse pressure. From the 7th to 15th beats, LVTMP and SV increased steadily, followed by a decreased HR due to the baroreflex. A decreased TMP, but not PCWP, caused a transient drop in SV with no changes in HR or pulse pressure during LBNP release. These results suggest that the pericardium constrains LV filling during LBNP release, enough to cause a small but significant drop of SV, even at low cardiac filling pressure in healthy humans.


Assuntos
Coração/fisiologia , Hemodinâmica/fisiologia , Pressão Negativa da Região Corporal Inferior/métodos , Pericárdio/fisiologia , Postura/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Cateterismo Cardíaco , Eletrocardiografia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Propulsora Pulmonar/fisiologia , Volume Sistólico/fisiologia
13.
J Appl Physiol (1985) ; 128(5): 1123-1129, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32240019

RESUMO

Women are at higher risk for developing heart failure with preserved ejection fraction (HFpEF). We examined the utility of peak exercise blood pressure (BP) in identifying preclinical features of HFpEF, namely vascular and cardiac stiffness in middle-aged women. We studied 47 healthy, nonobese middle-aged women (53 ± 5 yr). Oxygen uptake (V̇o2) and BP were assessed at rest and maximal treadmill exercise. Resting cardiac function and stiffness were assessed by echocardiography and invasive measurement (right heart catheterization) of left ventricular (LV) filling pressure under varying preloads. LV stiffness was calculated by curve fit of the diastolic portion of the pressure-volume curve. Aortic pulse-wave velocity was measured by arterial tonometry. Body fat was measured using dual-energy X-ray absorptiometry. Subjects in the highest exercise BP tertile had peak systolic BP of 201 ± 11 compared with 142 ± 19 mmHg in the lowest tertile (P < 0.001). Higher exercise BP was associated with increased age, percentage body fat, smaller LV size, slower LV relaxation, and increased LV and vascular stiffness. After adjustment, LV and arterial stiffness remained significantly associated with peak exercise BP. There was a trend toward increased body fat and slowed LV relaxation (both P < 0.07). In otherwise healthy middle-aged women, elevated exercise BP was independently associated with increased vascular stiffness and a smaller, stiffer LV, functional and structural risk factors characteristic for stages A and B HFpEF.NEW & NOTEWORTHY Women are at increased risk for heart failure with preserved ejection fraction (HFpEF) largely due to higher prevalence of arterial and cardiac stiffening. We were able to identify several subclinical markers of early (stages A and B) HFpEF pathophysiology largely on the basis of exercise blood pressure (BP) response in otherwise healthy middle-aged women. Exercise BP response may be an inexpensive screening tool to identify women at highest risk for developing future HFpEF.


Assuntos
Insuficiência Cardíaca , Rigidez Vascular , Pressão Sanguínea , Feminino , Humanos , Pessoa de Meia-Idade , Volume Sistólico , Função Ventricular Esquerda
14.
Artigo em Inglês | MEDLINE | ID: mdl-31109127

RESUMO

We sought to determine if there was an intergenerational association between parental weight, cardiorespiratory fitness (CRF), and disease status, with the prevalence of metabolic syndrome (MetSyn) in their young adult offspring. Young adults (n = 270, 21 ± 1 years, 53.3% female) were assessed for MetSyn and self-reported parent's CRF, body mass status, and disease status. MetSyn was present in 11.9% of participants, 27.4% had one or two components, and 58.5% had no components. A significantly higher percentage (93.9%) of young adults with MetSyn identified at least one parent as being overweight or obese, 84.8% reported low parental CRF and 87.9% reported a parent with disease (all p < 0.017). MetSyn in offspring is more likely when parents are perceived to have low CRF, increased body mass, and a diagnosis of disease. Evaluating the offspring of people with low CRF, elevated body mass, or who have a history of cardiovascular disease (CVD) or diabetes should be considered to promote early identification and treatment of young adults to reduce future premature CVD in these at-risk individuals.


Assuntos
Índice de Massa Corporal , Aptidão Cardiorrespiratória , Síndrome Metabólica/fisiopatologia , Pais , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Diabetes Mellitus , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Sobrepeso , Prevalência , Adulto Jovem
15.
Exp Gerontol ; 123: 36-44, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31095969

RESUMO

The age-associated increase in cardiac and central arterial stiffness is attenuated with lifelong (>25 years) endurance exercise in a dose-dependent manner. Remodelling of the extracellular matrix of cardiovascular structures may underpin these lifelong exercise adaptations in structural stiffness. The primary aim was to examine whether matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) levels are associated with aging and lifelong exercise-related changes in cardiac and central arterial stiffness. Plasma MMPs and TIMPs, left ventricular (LV) (LV stiffness constant) and central arterial stiffness (pulse wave velocity) were examined in healthy adults stratified into five groups based on age and lifelong weekly exercise frequency: (1) young sedentary adults (28-50 years), and older adults (>60 years) who had performed either: (a) sedentary (0-1 sessions/week), (b) casual (2-3 sessions/week), (c) committed (4-5 sessions/week) or (d) athletic (≥6 sessions/week) frequency of exercise. MMP-1 was significantly lower in young compared to older sedentary (p = 0.049). Except for TIMP-2 (p = 0.018 versus committed) and the ratio of MMP-2/TIMP-4 (p = 0.047 versus committed), MMP and TIMP expression was not significantly different in lifelong exercise groups (≥casual) compared to the older sedentary group. MMP-1, -3 had a weak positive relationship with central PWV (r = 0.17-0.25, p ≤ 0.050) but there were no significant relationships between MMPs or TIMPs and LV stiffness constant (p ≥ 0.148). In conclusion, there was not a clear or consistent difference in plasma MMPs and TIMPs with lifelong exercise dose despite exhibiting lower cardiovascular stiffness at the highest exercise levels.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Inibidores de Metaloproteinases de Matriz/sangue , Metaloproteinases da Matriz/sangue , Rigidez Vascular/fisiologia , Adaptação Fisiológica , Idoso , Fenômenos Fisiológicos Cardiovasculares , Correlação de Dados , Matriz Extracelular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Med Sci Sports Exerc ; 50(3): 494-501, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29077636

RESUMO

PURPOSE: The current study examined whether age-related changes in left ventricular (LV) longitudinal systolic function is an adaptation to a more sedentary lifestyle and can be preserved by lifelong exercise training. METHODS: A cross-sectional examination of 18 sedentary young (37 ± 6 yr), 29 sedentary seniors (71 ± 5 yr, 0-3 exercise sessions per week), and 26 seniors (68 ± 5 yr) who had performed a committed level (four to seven exercise sessions per week) of lifelong (>25 yr) exercise. Invasive right heart catheterization (pulmonary capillary wedge pressure) and noninvasive measures of LV function were collected at the following conditions: 1) supine rest, 2) during LV unloading (lower body negative pressure), and 3) LV loading (saline infusion). Ejection fraction and preload-recruitable stroke work (PRSW) were used to describe global LV systolic function, while peak systolic tissue velocity and longitudinal strain (LS) indicate LV longitudinal systolic function. To adjust LS for aging and training-related differences in LV preload and afterload, LV end-diastolic volume and end-systolic pressure (ESP) were included as covariates in ANCOVA models. RESULTS: Ejection fraction and PRSW were unaffected by aging or lifelong exercise (P = 0.22, P = 0.08, respectively). Peak systolic tissue velocities decreased with aging (P < 0.001) and sedentary seniors had a smaller LS compared with young (P = 0.023) and lifelong exercisers (P = 0.046). Preload-recruitable stroke work, ESP as a covariate did not alter group differences; however, LV end-diastolic volume eliminated group differences between senior groups. Longitudinal strain was preload dependent (P < 0.001), which was independent of aging and lifelong exercise. CONCLUSIONS: Sedentary aging leads to a reduction in systolic LS, which is attenuated by committed lifelong exercise due to improved LV diastolic filling.


Assuntos
Envelhecimento/fisiologia , Exercício Físico , Comportamento Sedentário , Função Ventricular Esquerda , Adulto , Idoso , Estudos Transversais , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole
17.
Prev Med Rep ; 7: 211-215, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28794957

RESUMO

Metabolic syndrome (MetSyn) represents a clustering of different metabolic abnormalities. MetSyn prevalence is present in approximately 25% of all adults with increased prevalence in advanced ages. The presence of one component of MetSyn increases the risk of developing MetSyn later in life and likely represents a high lifetime burden of cardiovascular disease risk. Therefore we pooled data from multiple studies to establish the prevalence of MetSyn and MetSyn component prevalence across a broad range of ethnicities. PubMed, SCOPUS and Medline databases were searched to find papers presenting MetSyn and MetSyn component data for 18-30 year olds who were apparently healthy, free of disease, and MetSyn was assessed using either the harmonized, National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII), American Heart Association/National Heart, Blood and Lung Institute (AHA/NHBLI), or International Diabetes Federation (IDF) definitions of MetSyn. After reviewing returned articles, 26,609 participants' data from 34 studies were included in the analysis and the data were pooled. MetSyn was present in 4.8-7% of young adults. Atherogenic dyslipidaemia defined as low high density lipoprotein (HDL) cholesterol was the most prevalent MetSyn component (26.9-41.2%), followed by elevated blood pressure (16.6-26.6%), abdominal obesity (6.8-23.6%), atherogenic dyslipidaemia defined as raised triglycerides (8.6-15.6%), and raised fasting glucose (2.8-15.4%). These findings highlight that MetSyn is prevalent in young adults. Establishing the reason why low HDL is the most prevalent component may represent an important step in promoting primary prevention of MetSyn and reducing the incidence of subsequent clinical disease.

18.
Med Sci Sports Exerc ; 38(8): 1384-8, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16888449

RESUMO

PURPOSE: This study aimed to determine whether sedentary overweight subjects with type 2 diabetes have impaired diastolic function compared with equally sedentary and overweight nondiabetic subjects. METHODS: Mitral valve pulsed Doppler echocardiography and tissue Doppler imaging (TDI) were used to assess left ventricular structure and diastolic function in 40- to 60-yr-old sedentary overweight subjects with type 2 diabetes (N = 13) and age- and body mass-matched sedentary nondiabetic subjects (N = 15). Pseudonormal filling was identified using preload reduction and TDI. RESULTS: Traditional Doppler mitral inflow parameters were not different between groups; however, early diastolic relaxation, as measured by peak early mitral annular velocity (E') and the ratio of E' and peak late mitral annular velocity (E'/A'), was reduced in type 2 diabetic subjects (P < 0.05). The ratio of peak early mitral inflow (E) to E' (E/E'), an estimate of left ventricular filling pressure, was also higher in the type 2 diabetes group (P < 0.05). The proportions of diastolic impairment (69 vs 40%) and pseudonormal filling (39 vs 20%) were not different between groups (P = 0.18). CONCLUSION: These findings suggest that type 2 diabetes has an effect on diastolic function that is independent of age and body composition.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Diástole/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Distribuição de Qui-Quadrado , Ecocardiografia Doppler de Pulso , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso , Consumo de Oxigênio/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem
19.
J Appl Physiol (1985) ; 121(2): 528-36, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27402556

RESUMO

Sedentary aging leads to left ventricular (LV) and vascular stiffening due in part to advanced glycation end-products (AGEs) cross-linking of extracellular matrix proteins. Vigorous lifelong exercise ameliorates age-related cardiovascular (CV) stiffening and enhances exercise LV function, although this effect is limited when exercise is initiated later in life. We hypothesized that exercise training might be more effective at improving the impact of age-related CV stiffening during exercise when combined with an AGE cross-link breaker (Alagebrium). Sixty-two seniors (≥60 yr) were randomized into four groups: sedentary + placebo, sedentary + Alagebrium, exercise + placebo, and exercise + Alagebrium for 1 yr. Moderate-intensity aerobic exercise was performed 3-4 sessions/wk; controls underwent similar frequency of yoga/balance training. Twenty-four similarly-aged, lifelong exercisers (4-5 sessions/wk) served as a comparator for the effect of lifelong exercise on exercising LV function. Oxygen uptake (Douglas bags), stroke index (SI; acetylene rebreathing), and effective arterial elastance (Ea) were collected at rest and submaximal and maximal exercise. Maximum O2 uptake (23 ± 5 to 25 ± 6 ml·kg(-1)·min(-1)) increased, while SI (35 ± 11 to 39 ± 12 ml/m(2)) and Ea (4.0 ± 1.1 to 3.7 ± 1.2 mmHg·ml(-1)·m(-2)) were improved across all conditions with exercise, but remained unchanged in controls (exercise × time, P ≤ 0.018). SI or Ea were not affected by Alagebrium (medication × time, P ≥ 0.468) or its combination with exercise (interaction P ≥ 0.252). After 1 yr of exercise plus Alagebrium, exercise SI and Ea remained substantially below that of lifelong exercisers (15-24 and 9-22%, respectively, P ≤ 0.415). In conclusion, Alagebrium plus exercise had no synergistic effect on exercise LV function and failed to achieve levels associated with lifelong exercise, despite a similar exercise frequency.


Assuntos
Terapia por Exercício/métodos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Tiazóis/administração & dosagem , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Comportamento de Redução do Risco , Comportamento Sedentário , Resultado do Tratamento
20.
Circ Cardiovasc Imaging ; 9(11)2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27903541

RESUMO

BACKGROUND: Recent reports have suggested that long-term, intensive physical training may be associated with adverse cardiovascular effects, including the development of myocardial fibrosis. However, the dose-response association of different levels of lifelong physical activity on myocardial fibrosis has not been evaluated. METHODS AND RESULTS: Seniors free of major chronic illnesses were recruited from predefined populations based on the consistent documentation of stable physical activity over >25 years and were classified into 4 groups by the number of sessions/week of aerobic activities ≥30 minutes: sedentary (group 1), <2 sessions; casual (group 2), 2 to 3 sessions; committed (group 3), 4 to 5 sessions; and Masters athletes (group 4), 6 to 7 sessions plus regular competitions. All subjects underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging, including late gadolinium enhancement assessment of fibrosis. Ninety-two subjects (mean age 69 years, 27% women) were enrolled. No significant differences in age or sex were seen between groups. Median peak oxygen uptake was 25, 26, 32, and 40 mL/kg/min for groups 1, 2, 3, and 4, respectively. Cardiac magnetic resonance imaging demonstrated increasing left ventricular end-diastolic volumes, end-systolic volumes, stroke volumes, and masses with increasing doses of lifelong physical activity. One subject in group 2 had late gadolinium enhancement in a noncoronary distribution, and no subjects in groups 3 and 4 had evidence of late gadolinium enhancement. CONCLUSIONS: A lifelong history of consistent physical activity, regardless of dose ranging from sedentary to competitive marathon running, was not associated with the development of focal myocardial fibrosis.


Assuntos
Cardiomegalia Induzida por Exercícios , Cardiomiopatias/etiologia , Exercício Físico , Miocárdio/patologia , Remodelação Ventricular , Fatores Etários , Idoso , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Aptidão Cardiorrespiratória , Meios de Contraste/administração & dosagem , Estudos Transversais , Teste de Esforço , Feminino , Fibrose , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Consumo de Oxigênio , Valor Preditivo dos Testes , Fatores de Risco , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA