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1.
Arch Suicide Res ; 27(4): 1312-1338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36237124

RESUMO

OBJECTIVE: Some countries have implemented systems to monitor suicides in real-time. These systems differ because of the various ways in which suicides are identified and recorded. The main objective of this study was to conduct an international comparison of major real-time suicide mortality surveillance systems to identify joint strengths, challenges, and differences, and thereby inform best-practice criteria at local, national, and international levels. METHODS: Five major real-time suicide mortality surveillance systems of various coverage levels were identified and selected for review via an internet-based scoping exercise and prior knowledge of existing systems. Key information including the system components and practices was collated from those organizations that developed and operate each system using a structured template. The information was narratively and critically synthesized to determine similarities and differences between the systems. RESULTS: The comparative review of the five established real-time suicide surveillance systems revealed more commonalities than differences overall. Commonalities included rapid, routine surveillance based on minimal, provisional data to facilitate timely intervention and postvention efforts. Identified differences include the timeliness of case submission and system infrastructure. CONCLUSION: The recommended criteria could promote replicable components and practices in real-time suicide surveillance while offering flexibility in adapting to regional/local circumstances and resource availability.HIGHLIGHTSEvidence-informed recommendations for current best practice in real-time suicide surveillance.Proposed comprehensive framework can be adapted based on available resources and capacity.Real-time suicide mortality data facilitates rapid data-driven decision-making in suicide prevention.

2.
Am J Physiol Heart Circ Physiol ; 320(3): H923-H941, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356960

RESUMO

With each heartbeat, the right ventricle (RV) inputs blood into the pulmonary vascular (PV) compartment, which conducts blood through the lungs at low pressure and concurrently fills the left atrium (LA) for output to the systemic circulation. This overall hemodynamic function of the integrated RV-PV-LA unit is determined by complex interactions between the components that vary over the cardiac cycle but are often assessed in terms of mean pressure and flow. Exercise challenges these hemodynamic interactions as cardiac filling increases, stroke volume augments, and cycle length decreases, with PV pressures ultimately increasing in association with cardiac output. Recent cardiopulmonary exercise hemodynamic studies have enriched the available data from healthy adults, yielded insight into the underlying mechanisms that modify the PV pressure-flow relationship, and better delineated the normal limits of healthy responses to exercise. This review will examine hemodynamic function of the RV-PV-LA unit using the two-element Windkessel model for the pulmonary circulation. It will focus on acute PV and LA responses that accommodate increased RV output during exercise, including PV recruitment and distension and LA reservoir expansion, and the integrated mean pressure-flow response to exercise in healthy adults. Finally, it will consider how these responses may be impacted by age-related remodeling and modified by sex-related cardiopulmonary differences. Studying the determinants and recognizing the normal limits of PV pressure-flow relations during exercise will improve our understanding of cardiopulmonary mechanisms that facilitate or limit exercise.


Assuntos
Função do Átrio Esquerdo , Exercício Físico , Coração/fisiologia , Hemodinâmica , Pulmão/irrigação sanguínea , Circulação Pulmonar , Função Ventricular Direita , Adaptação Fisiológica , Fatores Etários , Feminino , Voluntários Saudáveis , Humanos , Masculino , Modelos Cardiovasculares , Fatores Sexuais , Fatores de Tempo
3.
Ultrasound Obstet Gynecol ; 54(3): 350-358, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30426576

RESUMO

OBJECTIVE: To evaluate left ventricular (LV) mechanics in the second trimester of healthy pregnancy and to determine the influence of underpinning hemodynamics (heart rate (HR), preload and afterload) on LV mechanics during gestation. METHODS: This was a cross-sectional study of 18 non-pregnant, 14 nulliparous pregnant (22-26 weeks' gestation) and 13 primiparous postpartum (12-16 weeks after delivery) women. All pregnant and postpartum women had uncomplicated, singleton gestations. Cardiac structure and function were assessed using echocardiography. LV mechanics, specifically longitudinal strain, circumferential strain and twist/untwist, were measured using speckle-tracking echocardiography. Differences between groups were identified using ANCOVA, with age, HR, end-diastolic volume (EDV) and systolic blood pressure (SBP) as covariates. Relationships between LV mechanics and hemodynamics were examined using Pearson's correlation. RESULTS: There were no significant differences in LV structure and traditional measurements of systolic and diastolic function between the three groups. Pregnant women, compared with non-pregnant ones, had significantly higher resting longitudinal strain (-22 ± 2% vs -17 ± 3%; P = 0.002) and basal circumferential strain (-23 ± 4% vs -16 ± 2%; P = 0.001). Apical circumferential strain and LV twist and untwist mechanics were similar between the three groups. No statistically significant relationships were observed between LV mechanics and HR, EDV or SBP within the groups. CONCLUSIONS: Compared to the non-pregnant state, pregnant women in the second trimester of a healthy pregnancy have significantly greater resting systolic function, as assessed by LV longitudinal and circumferential strain. Contrary to previous work, these data show that healthy pregnant women should not exhibit reductions in resting systolic function between 22 and 26 weeks' gestation. The enhanced myocardial contractile function during gestation does not appear to be related to hemodynamic load and could be the result of other physiological adaptations to pregnancy. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Adaptação Fisiológica/fisiologia , Segundo Trimestre da Gravidez/fisiologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Estudos Transversais , Ecocardiografia , Feminino , Hemodinâmica , Humanos , Gravidez , Reino Unido/epidemiologia
4.
Climacteric ; 20(5): 476-483, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28786704

RESUMO

OBJECTIVES: Cardiovascular function generally decreases with age, but whether this decrease differs between men and women is unclear. Our aims were twofold: (1) to investigate age-related sex differences in left ventricular (LV) structure, function and mechanics, and (2) to compare these measures between pre- and postmenopausal women in the middle-aged group. METHODS: Resting echocardiography was performed in a cross-sectional sample of 82 healthy adults (14 young men, 19 middle-aged men, 15 young women, 34 middle-aged women: 15 premenopausal and 19 postmenopausal). Two-way ANOVAs were used to examine sex × age interactions, and t-tests to compare pre- and postmenopausal women (α < 0.1). RESULTS: Normalized LV mass, stroke volume and end-diastolic volume were significantly lower in middle-aged than young men, but this difference was smaller between middle-aged and young women. Peak systolic apical mechanics were significantly greater in middle-aged men than in middle-aged women, but not between young men and women. Postmenopausal women had significantly lower LV relaxation and mechanics (torsion, twisting velocity and apical circumferential strain rates) compared with middle-aged premenopausal women. CONCLUSION: Our cross-sectional findings suggest that the hearts of men and women may age differently, with men displaying greater differences in LV volumes accompanied by differences in apical mechanics.


Assuntos
Envelhecimento/fisiologia , Ventrículos do Coração/anatomia & histologia , Pós-Menopausa/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Fatores Etários , Fenômenos Biomecânicos , Estudos Transversais , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Volume Sistólico
5.
Int J Cardiol ; 245: 263-270, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28735755

RESUMO

BACKGROUND: Preclinical studies have reported that a single treadmill session performed 24h prior to doxorubicin provides cardio-protection. We aimed to characterize the acute change in cardiac function following an initial doxorubicin treatment in humans and determine whether an exercise session performed 24h prior to treatment changes this response. METHODS: Breast cancer patients were randomized to either 30min of vigorous-intensity exercise 24h prior to the first doxorubicin treatment (n=13), or no vigorous exercise for 72h prior to treatment (control, n=11). Echocardiographically-derived left ventricular volumes, longitudinal strain, twist, E/A ratio, and circulating NT-proBNP, a marker of later cardiotoxicity, were measured before and 24-48h after the treatment. RESULTS: Following treatment in the control group, NT-proBNP, end-diastolic and stroke volumes, cardiac output, E/A ratio, strain, diastolic strain rate, twist, and untwist velocity significantly increased (all p≤0.01). Whereas systemic vascular resistance (p<0.01) decreased, and ejection fraction (p=0.02) and systolic strain rate (p<0.01) increased in the exercise group only. Relative to control, the exercise group had a significantly lower NT-proBNP (p<0.01) and a 46% risk reduction of exceeding the cut-point used to exclude acute heart failure. CONCLUSION: The first doxorubicin treatment is associated with acutely increased NT-proBNP, echocardiographic parameters of myocardial relaxation, left ventricular volume overload, and changes in longitudinal strain and twist opposite in direction to documented longer-term changes. An exercise session performed 24h prior to treatment attenuated NT-proBNP release and increased systolic function. Future investigations should verify these findings in a larger cohort and across multiple courses of doxorubicin.


Assuntos
Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/terapia , Cardiotoxinas/uso terapêutico , Teste de Esforço/tendências , Treinamento Intervalado de Alta Intensidade/tendências , Estudo de Prova de Conceito , Adulto , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Neoplasias da Mama/sangue , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Cardiotoxinas/efeitos adversos , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Exercício Físico/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia
6.
J Vet Cardiol ; 19(4): 339-350, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28615148

RESUMO

OBJECTIVES: To establish reference intervals for echocardiographic measures of longitudinal left ventricular function in adult English Springer spaniel (ESS) dogs. ANIMALS: This study involved 42 healthy adult ESS. METHODS: Animals were prospectively recruited from a general practice population in the United Kingdom. Dogs were examined twice, at least 12 months apart, to exclude dogs with progressive cardiac disease. Mitral annular plane systolic excursion, tissue Doppler imaging mitral annular velocities and two-dimensional speckle-tracking echocardiographic left ventricular longitudinal strain and strain rate were measured. Intraoperator and intraobserver variability were examined and reference intervals were calculated. The potential effects of body weight, age and heart rate on these variables were examined. RESULTS: Intraoperator and intraobserver variability was <10% for all parameters except tissue Doppler imaging E' (the peak velocity of early diastolic mitral annular motion as determined by pulsed wave Doppler) and two-dimensional speckle-tracking echocardiographic variables, which were all <20%. Thirty-nine dogs were used to create reference intervals. Significant (but mostly weak) effects of age, heart rate and body weight on were detected. Reference intervals were similar to previously published values in different breeds. CLINICAL SIGNIFICANCE: Breed specific reference intervals for measures of longitudinal left ventricular function in the ESS are presented.


Assuntos
Cães , Ecocardiografia/veterinária , Função Ventricular Esquerda/fisiologia , Animais , Ecocardiografia/métodos , Ecocardiografia Doppler , Feminino , Masculino , Valva Mitral , Reino Unido
7.
J Small Anim Pract ; 57(10): 520-528, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27492994

RESUMO

OBJECTIVES: To establish transthoracic echocardiographic reference intervals in adult English springer spaniel dogs. METHODS: Forty-two healthy adult English springer spaniels were prospectively recruited from a general practice population in the UK. Animals were examined twice, at least 12 months apart, to exclude dogs with progressive cardiac disease. Reference intervals were calculated using Box-Cox transformations and specific variables were depicted within an expert consensus range. Relationships of body mass, age and heart rate with cardiac structure and function were examined and functional assessments were compared with previous reports. Reference intervals were compared against published ratiometric indices and allometric scaling models. RESULTS: Thirty-nine dogs contributed to create the reference intervals. Significant relationships with bodyweight, age and heart rate were detected, although low coefficients of determination were found. Fractional shortening values were lower than has been reported in many breeds but Simpson-derived ejection fractions were similar to previously published breed-specific values. CLINICAL SIGNIFICANCE: Breed-specific reference intervals are reported allowing for more appropriate interpretation of echocardiographic assessments in the English springer spaniel.


Assuntos
Cães/anatomia & histologia , Ecocardiografia/veterinária , Fatores Etários , Animais , Peso Corporal , Feminino , Frequência Cardíaca , Estudos Longitudinais , Masculino , Estudos Prospectivos , Valores de Referência
8.
Spinal Cord ; 54(10): 822-829, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26754476

RESUMO

STUDY DESIGN: Two studies were conducted: Study-1 was cross-sectional; and Study-2 a longitudinal repeated measures design. OBJECTIVES: To examine the influence of functional electrical stimulation (FES) rowing training on cardiac structure and function in people with spinal cord injury (SCI). SETTING: A university sports science department and home-based FES-training. METHODS: Fourteen participants with C4-T10 SCI (American Spinal Injury Association Impairment Scale A or B) were recruited for the studies. Cardiac structure and function, and peak: oxygen uptake ([Vdot ]O2peak), power output (POpeak) and heart rate (HRpeak), were compared between two FES-untrained groups (male n=3, female n=3) and an FES-trained group (male n=3) in Study-1 and longitudinally assessed in an FES-naive group (male n=1, female n=4) in Study-2. Main outcome measures left ventricular-dimensions, volumes, mass, diastolic and systolic function, and [Vdot ]O2peak, POpeak and HRpeak. In Study-2, in addition to peak values, the [Vdot ]O2 sustainable over 30 min and the related PO and HR were also assessed. RESULTS: Sedentary participants with chronic SCI had cardiac structure and function at the lower limits of non-SCI normal ranges. Individuals with chronic SCI who habitually FES-row have cardiac structure and function that more closely resemble non-SCI populations. A programme of FES-rowing training improved cardiac structure and function in previously FES-naive people. CONCLUSION: FES-rowing training appears to be an effective stimulus for positive cardiac remodelling in people with SCI. Further work, with greater participant numbers, should investigate the impact of FES-rowing training on cardiac health in SCI. SPONSORSHIP: We thank the INSPIRE Foundation, UK, for funding these studies.


Assuntos
Estimulação Elétrica/métodos , Terapia por Exercício/métodos , Frequência Cardíaca/fisiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/reabilitação , Adulto , Pressão Sanguínea/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Feminino , Coração/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Projetos Piloto , Traumatismos da Medula Espinal/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana
9.
Spinal Cord ; 52(12): 880-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25266698

RESUMO

STUDY DESIGN: A training intervention study using functional electrical stimulation-rowing (FES-R) in a group of eight individuals with tetraplegia. OBJECTIVES: To assess the feasibility of a structured progressive FES-R training programme in people with tetraplegia, and to explore the number and type of FES-training sessions required to enable continuous FES-R for 30 min. SETTING: A fully integrated sports centre, elite rowing training centre and university sport science department. METHODS: Eight participants with chronic complete and incomplete tetraplegia (C4 to C7, American Spinal Injury Association Impairment Scale A, B and C) who had not previously used any form of FES-assisted exercise, participated in the study. Participants completed a progressive FES-assisted training programme building to three continuous 30-min FES-R sessions per week at 60-80% of their predetermined peak power output. Thereafter, rowing performance was monitored for 12 months. MAIN OUTCOME MEASURES: number and type of FES-training sessions required before achieving 30-min continuous FES-R, and FES-R average power output (POav) pre and post 12 months training. Participant feedback of perceived benefits was also documented. RESULTS: All participants were able to continuously FES-row for 30 min after completing 13±7 FES-R training sessions. Each individual POav during 30 min FES-R increased over 12 months FES-training. FES-R was found safe and well tolerated in this group of individuals with tetraplegia. CONCLUSION: Individuals with tetraplegia are able to engage in a progressive programme of FES-R training. Future research examining FES-R training as an adjunctive therapy in people with tetraplegia is warranted.


Assuntos
Estimulação Elétrica , Terapia por Exercício/métodos , Quadriplegia/reabilitação , Adulto , Terapia por Exercício/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Consumo de Oxigênio , Condicionamento Físico Humano , Resultado do Tratamento , Adulto Jovem
10.
Int J Sports Med ; 33(5): 333-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22377942

RESUMO

Marathon running can increase circulating cardiac troponin above the diagnostic criteria for myocardial infarction. We determined whether prior-exercise experience (training history) might be related to the magnitude of immediate post-race troponin release following completion of the London Marathon in a group of non-elite runners. Using a prospective study design, 52 runners were recruited into either HIGH T-E (trained-experience) (n=27) or LOW T-E (n=25) groups. Cardiac troponin I (cTnI) release following race completion was compared between these 2 groups. To examine relationships between cTnI release and participant demographic and indices of prior training experience an additional 52 runners who did not meet the criteria for either the HIGH T-E or LOW T-E groups were also recruited. The combined data from all 104 runners was analysed using multivariate linear regression analysis. The results revealed a significant difference in post marathon circulating cTnI between LOW T-E runners (median: 0.11 µg/L; interquartile range [IQR]: 0.03-0.18 µg/L) and HIGH T-E runners (median: 0.03 µg/L; IQR 0.02-0.057 µg/L) (p<0.05). Average miles run per week in the last 3 years, a marker of total training experience, encompassing training volume and duration, was negatively associated with post-marathon cTnI release (p<0.001).In conclusion, exercise-induced cTnI release is strongly related to previous training experience.


Assuntos
Aptidão Física/fisiologia , Descanso/fisiologia , Troponina I/sangue , Adulto , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Resistência Física , Estudos Prospectivos , Corrida/fisiologia
12.
Curr Med Chem ; 18(23): 3457-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21756239

RESUMO

Exercise training represents a successful and powerful strategy to prevent future cardiovascular disease. Paradoxically, performance of exercise is also associated with an increased risk of acute cardiac events. Accordingly, patients may present to hospital with cardiac symptoms following a bout of unaccustomed physical effort (e.g. exercise). Current guidelines for the identification of an acute myocardial infarction (AMI) importantly depend on the presence of cardiac troponin as a highly sensitive marker of cardiac damage. However, a number of studies have reported elevated cardiac troponin levels in asymptomatic, healthy subjects after endurance exercise (such as a marathon, prolonged cycling or prolonged walking). These observations indicate that elevated cardiac troponin levels can be the result of cardiac ischemia, and subsequent necrosis, but also may be related to strenuous exercise. In this paper, we present three different clinical cases of post-exercise elevations in cardiac troponins, each with a distinct clinical presentation. These case studies emphasize that a detailed assessment of all symptoms and a thorough patient-history are prerequisite for accurate interpretation of a positive cardiac troponin test following exercise.


Assuntos
Exercício Físico , Troponina/sangue , Doença Aguda , Adulto , Biomarcadores/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico
13.
Scand J Med Sci Sports ; 21(2): 244-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19919634

RESUMO

Numerous studies have observed cardiac biomarker release with prolonged exercise. Despite this, we are unsure as to the constituent aspects of any given exercise bout that may be important in promoting cardiac biomarker release. This study examined the influence of exercise duration and intensity on the appearance of cardiac biomarkers. Twenty-one subjects ran for 45, 90 and 180 min at 85% and 95% of their individual anaerobic threshold on six different days randomized. Cardiac troponin I (cTnI) and N-terminal pro-brain natiuretic peptide (NT-proBNP) were assayed from blood samples collected before, 30 min and 3 h post-exercise. NT-proBNP was elevated after all exercise trials (range before: 21-32; range post: 38-67 ng/L). Peak post-exercise concentrations of NT-proBNP were associated with exercise duration (P=0.049), but not exercise intensity (P=0.451). cTnI was elevated after all exercise trials (range before: 0.007-0.011; range post: 0.008-0.021 µg/L). Peak post-exercise concentrations of cTnI were associated with exercise duration (P=0.003) and intensity (P=0.037). Data suggest that while both cTnI and NT-proBNP increased after all exercise trials, the mediating effect of duration influenced both NT-proBNP and cTnI while intensity influenced only cTnI.


Assuntos
Miocárdio/metabolismo , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Esforço Físico/fisiologia , Corrida/fisiologia , Troponina I/sangue , Adulto , Análise de Variância , Biomarcadores/sangue , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade
14.
Acta Physiol (Oxf) ; 200(4): 291-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20608902

RESUMO

AIM: Alterations in the carotid baroreflex (CBR) control of arterial pressure may explain the reduction in arterial pressure and left ventricular (LV) function after prolonged exercise. We examined the CBR control of heart rate (HR) and mean arterial pressure (MAP), in addition to changes in LV function, pre- to post-exercise. METHODS: Seven males (age, mean ± SEM; 29 ± 4 years) completed 4 h of ergometer rowing at a workload of 10-15% below the lactate threshold. The CBR control of HR and MAP was assessed via the rapid neck-suction/pressure protocol. LV systolic function was measured by echocardiography, where ejection fraction (EF), the ratio of systolic blood pressure to end systolic volume (SBP/ESV) and stroke volume (SV) were estimated. RESULTS: Following exercise MAP was reduced (12 ± 3%) and HR was elevated (35 ± 5%; P < 0.05). Furthermore, CBR control of MAP was relocated to the left on the stimulus-response curve (P < 0.05) demonstrating that the CBR operated around a lower arterial pressure. Concomitantly, LV systolic function was reduced, indicated by a decrease in EF (22 ± 2%), SBP/ESV (32 ± 14%) and SV (25 ± 5%, P < 0.05). The reduced EF and SBP/ESV were associated with the decreased MAP operating point (r² = 0.71 and r² = 0.47, respectively, P < 0.05). CONCLUSION: The CBR is reset after prolonged exercise to a lower prevailing arterial pressure. This resetting of the CBR may contribute to the reduction arterial pressure and LV function after exercise.


Assuntos
Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Artérias Carótidas/fisiologia , Exercício Físico/fisiologia , Adulto , Ecocardiografia , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Masculino , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
15.
Scand J Med Sci Sports ; 20(6): 843-52, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19883392

RESUMO

This investigation determined the efficacy of a tart cherry juice in aiding recovery and reducing muscle damage, inflammation and oxidative stress. Twenty recreational Marathon runners assigned to either consumed cherry juice or placebo for 5 days before, the day of and for 48 h following a Marathon run. Markers of muscle damage (creatine kinase, lactate dehydrogenase, muscle soreness and isometric strength), inflammation [interleukin-6 (IL-6), C-reactive protein (CRP) and uric acid], total antioxidant status (TAS) and oxidative stress [thiobarbituric acid reactive species (TBARS) and protein carbonyls] were examined before and following the race. Isometric strength recovered significantly faster (P=0.024) in the cherry juice group. No other damage indices were significantly different. Inflammation was reduced in the cherry juice group (IL-6, P<0.001; CRP, P<0.01; uric acid, P<0.05). TAS was ~10% greater in the cherry juice than the placebo group for all post-supplementation measures (P<0.05). Protein carbonyls was not different; however, TBARS was lower in the cherry juice than the placebo at 48 h (P<0.05). The cherry juice appears to provide a viable means to aid recovery following strenuous exercise by increasing total antioxidative capacity, reducing inflammation, lipid peroxidation and so aiding in the recovery of muscle function.


Assuntos
Antioxidantes/uso terapêutico , Tolerância ao Exercício/efeitos dos fármacos , Inflamação/prevenção & controle , Preparações de Plantas/uso terapêutico , Prunus , Corrida/fisiologia , Adaptação Fisiológica , Adulto , Análise de Variância , Anti-Inflamatórios/uso terapêutico , Biomarcadores , Proteína C-Reativa , Feminino , Humanos , Inflamação/tratamento farmacológico , Interleucina-6 , Contração Isométrica/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Ácido Úrico
16.
Int J Sports Med ; 29(2): 129-33, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17960504

RESUMO

The present study aimed to examine maximum heart rate (HRmax) in elite athletes. 130 (68 male, 23.2 +/- 4.8 years, 62 female, 21.0 +/- 5.1 years) endurance trained athletes, 40 (24 male, 24.0 +/- 5.6 years, 16 female, 22.8 +/- 4.6 years) anaerobically trained athletes, and 95 (39 male, 24.8 +/- 4.8 years, 56 female, 23.0 +/- 4.8 years) sedentary participants entered the study. All participants undertook a standard ramp protocol to volitional exhaustion to establish HRmax. Significant differences in HRmax were identified due to mode of exercise (p < 0.001) and gender (p = 0.001). The mean HRmax for the three modes of exercise were; aerobic 190.3 (SEE = 0.66), anaerobic 190.1 (SEE = 1.12) and sedentary 194.8 (SEE = 0.73) beats . min (-1) estimated at the average age of 23.1 years. The slope parameter for age varied between genders, the beta slope for females being significantly more negative than male subjects (- 1.1 beats . min (-1) . year (-1) vs. - 0.55 beats . min (-1) . year (-1), respectively). The predictive HRmax equation for male athletes was HRmax = 202 - 0.55 x age, and for female athletes it was HRmax = 216 - 1.09 x age. HRmax is similar between aerobically and anaerobically trained athletes. HRmax is significantly lower in athletes compared with age matched sedentary counterparts. The mechanisms underlying the lower HRmax remain to be elucidated.


Assuntos
Frequência Cardíaca/fisiologia , Aptidão Física/fisiologia , Adaptação Fisiológica/fisiologia , Adolescente , Adulto , Teste de Esforço/métodos , Feminino , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Reino Unido
17.
Br J Sports Med ; 42(4): 304-5, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17720799

RESUMO

A growing body of evidence reporting altered cardiac function and myocardial damage after arduous exercise, together with the increased prevalence of arrhythmias observed in highly trained athletes, suggests that repetitive bouts of prolonged, arduous exercise may be deleterious to long-term cardiac health. We report the case of an experienced, highly trained marathon runner who died suddenly while running. On post-mortem examination, left ventricle hypertrophy and idiopathic interstitial myocardial fibrosis was found. We believe that life-long, repetitive bouts of arduous physical activity resulted in fibrous replacement of the myocardium, causing a pathological substrate for the propagation of fatal arrhythmias.


Assuntos
Morte Súbita Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/patologia , Miocárdio/patologia , Resistência Física/fisiologia , Corrida/fisiologia , Fibrose/patologia , Humanos , Masculino , Pessoa de Meia-Idade
18.
Br J Sports Med ; 41(9): 613-5; discussion 615, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17261549

RESUMO

Collapse after prolonged endurance exercise is common and usually benign. This case study reports a triathlete who suffered a vaso-vagal associated collapsed after exercise. Misdiagnosis of myocardial injury in the presence of elevated cardiac troponins and ECG anomalies led to inappropriate management and highlights the difficulty in treating the collapsed athlete following arduous exercise.


Assuntos
Resistência Física/fisiologia , Esportes/fisiologia , Síncope Vasovagal/diagnóstico , Troponina I/metabolismo , Adulto , Ciclismo/fisiologia , Diagnóstico Diferencial , Eletrocardiografia , Testes Hematológicos , Humanos , Masculino , Miocardite/diagnóstico , Pericardite/diagnóstico , Corrida/fisiologia , Natação/fisiologia , Síncope Vasovagal/etiologia
19.
Exp Physiol ; 92(2): 383-90, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17158180

RESUMO

This study examined whether left ventricular function was reduced during 3 h of semi-recumbent ergometer cycling at 70% of maximal oxygen uptake while preload to the heart was maintained via saline infusion. Indices of left ventricular systolic function (end-systolic blood pressure-volume relationship, SBP/ESV) and diastolic filling (ratio of early to late peak filling velocities into the left ventricle, E:A) were calculated during recovery and compared with baseline resting data. During exercise in seven healthy, trained male subjects, an arterial catheter allowed continuous assessment of arterial pressure, stroke volume (SV), cardiac output ( ) and an index of contractility (dP/dt(max)). A venous catheter assessed that central venous pressure (CVP) was maintained throughout rest, exercise and 10 min into recovery. Both systolic blood pressure and heart rate (HR) increased with the onset of exercise (from 132 +/- 5 to 185 +/- 19 mmHg and from 66 +/- 9 to 135 +/- 23 beats min(-1); increases from rest to the end of the first 5 min of exercise in SBP and HR, respectively) but systolic blood pressure did not change from 30 to 180 min of exercise ( approximately 150 mmHg), while heart rate only increased by 8 +/- 9 beats min(-1) (means +/- s.d.; P > 0.05). The attenuated increase in HR compared with other studies suggests that the maintained CVP ( approximately 5 mmHg) helped to prevent cardiovascular drift in this protocol. Stroke volume, and dP/dt(max) were all increased with the onset of exercise (from 85 +/- 8 to 120 +/- 18 ml, from 5.4 +/- 1.3 to 16.5 +/- 3.3 l min(-1) and from 14.4 +/- 4 to 28 +/- 8 mmHg s(-1); values from rest to the end of the first 5 min of exercise for SV, and dP/dt(max), respectively) and were maintained during exercise. There was no difference in the SBP/ESV ratio from pre- to postexercise. Conversely, E:A was reduced from 2.0 +/- 0.4 to 1.6 +/- 0.5 postexercise (P < 0.05), returning to normal values at 24 h postexercise. This change in diastolic filling could not be fully explained (r(2) = 0.39) by an increased heart rate and, with CVP unchanged, it is likely to represent some depression of intrinsic relaxation properties of left ventricular myocytes. Three hours of semi-supine cycling resulted in no evidence of a depression in left ventricular systolic function, while left ventricular diastolic function declined postexercise.


Assuntos
Adaptação Fisiológica , Exercício Físico/fisiologia , Contração Muscular , Músculo Esquelético/metabolismo , Resistência Física/fisiologia , Função Ventricular Esquerda , Adulto , Pressão Sanguínea , Pressão Venosa Central , Diástole , Frequência Cardíaca , Humanos , Masculino , Contração Miocárdica , Consumo de Oxigênio , Recuperação de Função Fisiológica , Volume Sistólico , Sístole , Fatores de Tempo
20.
Br J Sports Med ; 40(6): 536-40; discussion 540, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16547144

RESUMO

OBJECTIVE: To investigate indices of left ventricular (LV) function before and after a 224 km Ironman triathlon, specifically in the presence of unaltered haemodynamic loading. METHOD: LV loading and function were assessed before and after the race using M mode and Doppler echocardiography in 39 (mean (SD) age 33 (8) years, body mass 77.6 (8.6) kg; 36 male) triathletes in the Trendelenburg position. Specifically left ventricular end diastolic volume (LVEDV) was assessed to estimate preload, and systolic blood pressure to estimate afterload as well as heart rate (HR). Systolic functional indices included ejection fraction (EF) and the end systolic pressure/volume ratio (ESPV), and diastolic functional indices included peak mitral flow velocity in early (E) and atrial (A) filling as well as the ratio E/A. Data obtained before and after the race were compared by t tests, and delta LV functional indices were correlated with delta heart rate. RESULTS: Preload (LVEDV: 143 (34) ml before v 147 (34) ml after) and afterload (systolic blood pressure 121 (13) v 115 (20) mm Hg) were not significantly altered after the race (p>0.05), nor were EF (61 (8)% v 58 (10)%) and ESPV (2.4 (0.9) v 2.1 (0.8) mm Hg/cm(3)). The diastolic filling ratio E/A was significantly reduced after the race (1.73 (0.25) v 1.54 (0.23); p<0.05) due primarily to a reduction in E. HR was significantly higher after the race (57 (9) v 75 (8) beats/min; p<0.05), but delta HR was not related to delta E/A (p>0.05). CONCLUSION: When preload and afterload are unaltered after the race, because of the adoption of a unique assessment posture, LV systolic function is not depressed. A depression in LV diastolic function persists which is not explained by an increase in heart rate after the race.


Assuntos
Ciclismo/fisiologia , Pressão Sanguínea/fisiologia , Corrida/fisiologia , Natação/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Diástole/fisiologia , Ecocardiografia Doppler , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Fadiga Muscular/fisiologia , Resistência Física/fisiologia , Sístole/fisiologia
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