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1.
Einstein (Sao Paulo) ; 18: eAO5256, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32267367

RESUMEN

OBJECTIVE: To describe and identify the importance of different indicators of the aerobic and anaerobic fitness of male ultra-trail runners according to their level of participation (regional or national). METHODS: Forty-four male ultra-trail runners were assessed (36.5±7.2 years). They were classified as regional (n=25) and national (n=19). Wingate test was used to assess the anaerobic pathway. A progressive incremental running test was performed and ventilatory thresholds registered, in parallel to heart rate and lactate concentration at the end of the protocol. Comparison between groups was performed using independent samples t-test. RESULTS: No significant differences were found between outputs derived from Wingate test. For aerobic fitness, while examining absolute values, differences were uniquely significant for the second ventilatory threshold (ultra-trail regional runners: 3.78±0.32L.min-1; ultra-trail national runners: 4.03±0.40L.min-1 p<0.05). Meantime, when aerobic fitness was expressed per unit of body mass, differences were significant for the second ventilatory threshold (ultra-trail regional runners: 50.75±6.23mL.kg-1.min-1; ultra-trail national runners: 57.88±4.64mL.kg-1.min-1 p<0.05) and also maximum volume of oxygen (ultra-trail regional runners: 57.33±7.66mL.kg-1.min-1; ultra-trail national runners: 63.39±4.26mL.kg-1.min-1 p<0.05). CONCLUSION: This study emphasized the importance of expressing physiological variables derived from running protocols per unit of body mass. Also, the second ventilatory threshold appears to be the best and the only aerobic fitness variable to distinguish between trail runners according to competitive level. Maximal oxygen uptake seems of relative interest to distinguish between long distance runners according to competitive level.


Asunto(s)
Atletas , Carrera/fisiología , Adulto , Umbral Anaerobio/fisiología , Índice de Masa Corporal , Estudios Transversales , Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Oxígeno/metabolismo , Valores de Referencia , Estadísticas no Paramétricas , Factores de Tiempo
2.
Medicine (Baltimore) ; 99(14): e19529, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32243369

RESUMEN

Resting heart rate, a simple and useful indicator of autonomic function, and its imbalance has emerged as an independent predictor of cardio metabolic diseases. Nonalcoholic fatty liver disease (NAFLD) is increasingly being diagnosed worldwide and is strongly associated with the features of cardiometabolic diseases. This study aimed to examine the association between resting heart rate and NAFLD in postmenopausal women.The cross-sectional study included 1017 postmenopausal women aged ≥46 years, who attended a health examination program. Resting heart rate and NAFLD were measured in all subjects who underwent a medical examination. Resting heart rate quartiles were categorized as follows: Q1: 56 to 65, Q2: 66 to 71, Q3: 72 to 78, and Q4: 79 to 99 beats/min. The odds ratios and 95% confidence intervals for NAFLD were calculated after adjusting for confounding variables across resting heart rate quartiles using multiple logistic regression analysis.The prevalence of NAFLD increased with increasing resting heart rate quartiles: 28.2% for Q1, 31.5% for Q2, 33.4% for Q3, and 38.1% for Q4 (P < .001). Compared to the 1st quartile, the odds ratio (95% confidence intervals) of NAFLD in the 4th quartile of resting heart rates was 2.11 (1.17-3.42) after adjusting for age, body mass index, cigarette smoking, regular exercise, blood pressure, total cholesterol, triglyceride, aspartate aminotransferase, and alanine aminotransferase levels.Resting heart rate was positively associated with NAFLD in postmenopausal women, suggesting that it could be a useful additional measure to assess the risk for NAFLD in postmenopausal women.


Asunto(s)
Frecuencia Cardíaca/fisiología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Posmenopausia/fisiología , Factores de Edad , Anciano , Glucemia , Presión Sanguínea , Índice de Masa Corporal , Fumar Cigarrillos/epidemiología , Estudios Transversales , Femenino , Humanos , Lípidos/sangre , Pruebas de Función Hepática , Persona de Mediana Edad
3.
An Acad Bras Cienc ; 92(1): e20181184, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32294694

RESUMEN

Studies have shown improvement of the cardiac autonomic balance in post-bariatric patients. Most of these studies included patients using drugs interfering in the autonomic nervous system. This study assessed the time course of changes in the sympathovagal balance after bariatric surgery (Roux-en-Y gastric bypass) in 26 women free from drugs. A 10-min electrocardiographic recording was obtained at baseline and at 3 and 6 months after surgery. Temporal and spectral domains of heart rate variability were analysed. The time domain components of cardiac vagal modulation increased progressively after surgery. In the frequency domain, high frequency power increased from 24.9 at baseline (18.0 to 46.3) to 44.5 at 3 months (23.4 to 65.6), and 54.1 at 6 months after surgery (37.6 to 64.0) (median and IQR in normalized units). Low frequency spectral power decreased from 56.2 at baseline (39.6 to 74.4) to 36.8 at 6 months after surgery (24.9 to 53.9) (P= 0.036). Low frequency/high frequency ratio decreased from 2.3 at baseline (1.0 to 4.2) to 0.8 at 6 months after surgery (0.4 to 1.3) (P= 0.038). Progressive shift towards predominance of vagal tonus was detected in the follow-up. Most of the patients recovered low frequency/high frequency at 6 months after surgery.


Asunto(s)
Cirugía Bariátrica , Frecuencia Cardíaca/fisiología , Obesidad/cirugía , Adulto , Anciano , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Humanos , Hipertensión/etiología , Estudios Longitudinales , Persona de Mediana Edad , Obesidad/complicaciones , Pérdida de Peso/fisiología , Adulto Joven
4.
J Sports Sci ; 38(9): 970-984, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32154760

RESUMEN

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI -32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI -2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10-15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.


Asunto(s)
Presión Sanguínea/fisiología , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Entrenamiento de Intervalos de Alta Intensidad , Rigidez Vascular/fisiología , Entrenamiento de Intervalos de Alta Intensidad/efectos adversos , Humanos , Infarto del Miocardio/etiología , Factores de Riesgo , Vasodilatación/fisiología , Fibrilación Ventricular/etiología
5.
J Sports Sci ; 38(9): 1018-1025, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32164498

RESUMEN

This study aimed to investigate between- and within-team changes in workload [PlayerLoad (PL), training impulse (TRIMP) and session rate of perceived exertion training load (sRPE-TL)], readiness [heart rate variability (HRV)], and physical performance [20-m sprint test (including 10-m split time), countermovement jump (CMJ) and yo-yo intermittent recovery test level 1 (YYIR1)] during 3-week intensified preparation periods in female, national Under18 (n = 12, age = 18.0 ± 0.5y, stature = 180.4 ± 7.5 cm, body mass = 72.7 ± 9.3 kg) and Under20 (n = 12, age = 19.6 ± 0.8y, stature = 178.6 ± 6.4 cm, body mass = 68.0 ± 5.9 kg) basketball teams. Under18 team revealed small-to-moderate statistically significantly higher values in workload [PL: p = 0.010; ES = Small; TRIMP: p = 0.004; ES = Moderate; sRPE-TL: p < 0.001; ES = Moderate] and moderately lower readiness values (p = 0.023; ES = Moderate) compared to Under20. Within-team analysis showed no differences in workload in Under20 and statistically significant reduction (p < 0.05) in Week3 (taper period) in Under18. Pre- and post-preparation changes showed Under18 increasing only YYIR1 performance (p < 0.001; ES = Very large). Differently, Under20 statistically improved in 10-m split time (p = 0.003; ES = Moderate), CMJ (p = 0.025; ES = Moderate) and YYIR1 (p < 0.001; ES = Large). A constant adequate workload positively benefits players' readiness and physical performances during short intensified preparation periods. Conversely, using high workload with periodization strategies encompassing short overload and taper phases induced positive changes on players' aerobic performance, lower readiness values and no changes in anaerobic performances.


Asunto(s)
Rendimiento Atlético/fisiología , Baloncesto/fisiología , Acondicionamiento Físico Humano/métodos , Adolescente , Conducta Competitiva/fisiología , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Percepción/fisiología , Esfuerzo Físico/fisiología , Carga de Trabajo , Adulto Joven
6.
J Sports Sci ; 38(9): 1046-1052, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32175817

RESUMEN

Moderate-intensity continuous exercise (MICE) improves fat oxidation. High-intensity intermittent exercise (HIIE) is thought to have a greater potential for fat oxidation but it might be too demanding in the long term for patients. We hypothesized that an initial bout of HIIE could maximize fat oxidation during MICE and the following passive recovery. Eighteen healthy participants performed two acute isocaloric exercise sessions at random. MICE consisted of 45-min cycling at 50% of maximal aerobic power (Pmax). COMB began with five 1-min bouts of HIIE at Pmax (interspaced with 1-min recovery periods) followed by 35-min MICE. Gas exchange allowed substrate oxidation rate assessment.Expressed as a % of energy expenditure, fat oxidation (%) increased during in the passive recovery following COMB (Recovery: 36.0 ± 19.4 vs 23.0 ± 20.3%; ES: 0.66; p < 0.0001). An initial bout of HIIE preceding a prolonged moderate-intensity exercise may potentiate fat oxidation during the following recovery. This might be relevant for health management of overweight/obese persons.


Asunto(s)
Ejercicio Físico/fisiología , Entrenamiento de Intervalos de Alta Intensidad/métodos , Metabolismo de los Lípidos , Adulto , Metabolismo Energético , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Obesidad/terapia , Sobrepeso/terapia , Oxidación-Reducción , Intercambio Gaseoso Pulmonar , Adulto Joven
7.
Pan Afr Med J ; 35: 4, 2020.
Artículo en Francés | MEDLINE | ID: mdl-32117520

RESUMEN

Intensive and prolonged practice of sport can lead to cardiovascular and electrocardiographic changes. The purpose of this study was to describe the electrocardiographic changes in some young black Senegalese players practicing competitive basketball. We conducted a prospective descriptive analysis of surface electrocardiogram (ECG) findings related to young Senegalese Black players practicing competitive basketball. The study involved 40 young basketball players, 20 girls and 20 boys, whose average age was 17 ± 0.86 years (ranging from 17 to 19 years) and 15 ± 1.56 years (ranging from 13 to 18 years) respectively. Heart rate was lower among boys, 59 beats ± 9 beats (ranging from 42 to 85) than among girls 73 beats/ min ± 11 beats (ranging from 50 to 95) (p = 0.0004). The following features have been observed: repolarization abnormalities such as T-wave inversion V1-V4 in 3 cases (7.5%), right ventricular hypertrophy in 1 case (2.5%), right axis deviation (QRS axis) in 1 case (2.5%). Intensive and prolonged practice of basketball leads to electrocardiographic changes in the young black Senegalese players.


Asunto(s)
Arritmias Cardíacas/epidemiología , Baloncesto , Electrocardiografía , Frecuencia Cardíaca/fisiología , Adolescente , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Femenino , Humanos , Masculino , Estudios Prospectivos , Senegal , Adulto Joven
8.
Medicine (Baltimore) ; 99(10): e19401, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32150086

RESUMEN

BACKGROUND: The association of resting heart rate (RHR) and hypertension in adults is unclear. We aimed to perform a meta-analysis of cohort studies to clarify the association. METHODS: We searched PubMed and Embase from their inception to November 3, 2017, for published articles. We used a random effects model to combine study-specific relative risks (RRs) and 95% confidence intervals (CIs). We used restricted cubic spline functions to assess the dose-response relationship. RESULTS: Nine cohort articles (12 independent studies) with 79,399 individuals and more than 26,380 incident cases of hypertension were included. The summary RR for hypertension was 1.09 (95% CI: 1.06-1.13) with each 10 bpm increment in RHR. The cubic spline model suggested that when compared with 55.5 beats per minute, the risk of hypertension significantly increased with increasing levels of RHR (Pnonlinearity = 0.059). CONCLUSION: We found a linear dose-response association between RHR and incident hypertension in adults.


Asunto(s)
Relación Dosis-Respuesta a Droga , Frecuencia Cardíaca/fisiología , Hipertensión/tratamiento farmacológico , Adulto , Estudios de Cohortes , Frecuencia Cardíaca/efectos de los fármacos , Determinación de la Frecuencia Cardíaca/métodos , Humanos , Hipertensión/fisiopatología , Factores de Riesgo
9.
Georgian Med News ; (298): 94-99, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32141858

RESUMEN

Aim - to investigate the effect of oxidative stress on the autonomic nervous system state in patients with liver cirrhosis. In a randomized way with the preliminary startification by the presence of LC 81 patients - 55 (67.9%) males, 26 (32.1%) females, aged 46.9±10.8 years were included to the study after the signing the informed cosent. All the patients underwent the comprehensive clinical laboratory and instrumental examination of all organs and systems in accordance with the requirements of the modern medicine.Among the indicators of redox homeostasis the content of malondialdehyde (MDA) and of catalase (CAT) were determined. The study of autonomic nervous system (ANS) status was carried out using the registration of heart rate variability (HRV) before and after the physical activity. The results were processed on a personal computer in Statistica 6.0, RStudio v. 1.1.442 and R Commander v.2.4-4 using descriptive statistics. The difference was considered statistically significant if p<0.05. The results of HRV time parameters analysis before the physical activity revealed that MDA content negatively correlated with mean duration of NN (RR) intervals (RRNN), standard deviation of NN intervals (SDNN), the square root of the mean squared differences of successive NN interval (RMSSD), percent of consecutive NN intervals with difference more then 50 mc between (pNN 50%), percent of variation coefficient (CV%) and positively - with heart rate. This is verified by the fact that the CAT content positively correlated with RRNN, SDNN, RMSSD, pNN 50% and negatively - with heart rate.The results of the study of HRV spectral analysis correlation relationships revealed that MDA content negatively and CAT - positively correlated with total power (TP), high frequency (HF), low frequency (LF), very low frequency (VLF), LF/HF index, percent of very low frequency (%VLF), percent of low frequency (%LF), percent of high frequency (%HF). The results of analysis of HRV time analysis parameters after the physical activity revealed that the MDA content negatively correlated with CV% and the content of CAT positively correlated with SDNN, CV%. The results of the study of the correlation relationships of the HRV spectral analysis parameters after the physical activity revealed that the content of CAT positively correlated with TP, LF, VLF. Oxidative stress and the antioxidant defense system activity lack, as important pathogenetic parts of vascular tone dysfunction, have a significant effect on the ANS in patients with LC, causing the predominance of the sympathetic branch activity over the parasympathetic one. Oxidative stress, triggering the relevant pathogenetic mechanisms has an effect on the autonomic nervous system in patients with liver cirrhosis. However, the realization of the dominant influence of the sympathetic branch of the autonomic nervous system is minimized due to the decrease in the sensitivity of receptors to vasoconstrictors, including to neurotransmitters.


Asunto(s)
Sistema Nervioso Autónomo , Frecuencia Cardíaca/fisiología , Cirrosis Hepática , Estrés Oxidativo , Adulto , Anciano , Sistema Nervioso Autónomo/fisiología , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Neumol. pediátr. (En línea) ; 15(1): 251-256, Mar. 2020. tab
Artículo en Español | LILACS | ID: biblio-1088092

RESUMEN

Home cardio-respiratory monitoring began over 40 years ago with the aim of preventing sudden infant death. Although it has been shown that monitoring does not meet this objective, its prescription has been maintained in various clinical situations and with very different criteria. Consensus on the subject has not been able to define precisely the type of monitoring or the time required for different diseases. Among the diseases that still consider the indication of cardio-respiratory monitoring at home are: persistent apnea of prematurity, high-risk BRUE (Brief Resolved Unexplained Events), neurological or metabolic diseases with compromise of the respiratory center, convulsive cough, pathologic gastroesophageal reflux and technology-dependent patients (high flow nasal cannula (CNAF), noninvasive ventilation (NIV), invasive mechanical ventilation (IMV) to tracheostomy, and others). A review is presented on the development of cardio-respiratory monitoring at home, highlighting the true usefulness of this technology with a general proposal, which must be evaluated on a case-by-case basis and always taking into account the conditions that must be met to perform adequate monitoring and useful.


La monitorización cardio-respiratoria en domicilio se inició hace más de 40 años con el objetivo de prevenir la muerte súbita del lactante. Aun cuando se ha demostrado que la monitorización no cumple este objetivo, se ha mantenido su prescripción en diversas situaciones clínicas y con criterios muy diversos. Consensos acerca del tema no han llegado a definir con precisión el tipo de monitorización ni el tiempo requerido para distintas enfermedades. Dentro de las enfermedades que todavía consideran la indicación de monitorización cardio-respiratoria en domicilio se encuentran: apnea persistente del prematuro, BRUE (episodio breve resuelto inexplicado) de alto riesgo, enfermedades neurológicas o metabólicas con compromiso del centro respiratorio, tos convulsiva, reflujo gastroesofágico patológico y pacientes dependientes de tecnología (cánula nasal de alto flujo (CNAF), ventilación no invasiva (VNI), ventilación mecánica invasiva (VMI) a traqueostomía, y otros). Se presenta una revisión sobre el desarrollo de la monitorización cardio-respiratoria en domicilio, resaltando la verdadera utilidad que tendría esta tecnología con una propuesta general, que debe evaluarse caso a caso y siempre teniendo en cuenta las condiciones que deben cumplirse para realizar una monitorización adecuada y útil.


Asunto(s)
Humanos , Lactante , Apnea/fisiopatología , Frecuencia Respiratoria/fisiología , Frecuencia Cardíaca/fisiología , Monitoreo Fisiológico/métodos , Medición de Riesgo , Selección de Paciente , Servicios de Atención de Salud a Domicilio
11.
Am Heart J ; 222: 83-92, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32028139

RESUMEN

BACKGROUND: Rhythm-control strategy, including catheter ablation (CA) application, constitutes an integral part of atrial fibrillation (AF) management. However, elderly patients are underrepresented in clinical trials, and reports on patient-reported outcome of various rhythm-control treatments remain limited. Therefore, we aimed to investigate the application of a rhythm-control strategy for elderly patients with AF. METHODS: Using a prospective, multicenter Japanese registry, we analyzed 733 patients with AF aged ≥70 years who completed the Atrial Fibrillation Effect on Quality-of-Life (AFEQT) questionnaire at baseline and 1-year visit. Improvement in patient-reported quality-of-life (QOL) was assessed according to their initial treatment strategy. RESULTS: A total of 321 patients (43.8%) were managed with rhythm-control strategy, of which 125 (17.1%) received treatment with antiarrhythmic drugs (AADs) alone and 196 (26.7%) underwent CA. Compared with the rate-control group, the rhythm-control group was younger and less likely to have comorbid conditions but had lower baseline AFEQT-overall summary (OS) scores (71.8 [standard deviation 20.3] vs. 80.0 [standard deviation 16.1]; P < .001). After the first year, AFEQT-OS scores improved regardless of treatment strategies (ie, rate- or rhythm-control). After adjusting for confounders, CA implementation and a lower baseline AFEQT score were associated with meaningful improvement in QOL (changes in AFEQT-OS score ≥5). QOL improvement among subgroups of rhythm-control patients with AADs alone was not clinically meaningful. CONCLUSIONS: In contemporary Japanese clinical practice, rhythm-control strategy is widely implemented in elderly patients with AF, and CA use is associated with improvement in QOL in carefully selected patients.


Asunto(s)
Antiarrítmicos/uso terapéutico , Fibrilación Atrial/terapia , Ablación por Catéter/métodos , Medición de Resultados Informados por el Paciente , Guías de Práctica Clínica como Asunto , Mejoramiento de la Calidad/normas , Calidad de Vida , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/fisiopatología , Femenino , Estudios de Seguimiento , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Estudios Prospectivos , Sistema de Registros , Encuestas y Cuestionarios
12.
Expert Rev Med Devices ; 17(3): 159-165, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32101067

RESUMEN

Introduction: Several handheld thumb ECG devices for on-demand recording of heart rhythm have become available lately. These can be used both by health-care providers and purchased by laypersons for private use.Area covered: This profile describes the Coala Heart Monitor. This device differs from other handheld ECG monitors in three aspects: 1) it records both thumb and chest ECGs, 2) it uses both RR-dispersion and P-wave morphology for detecting atrial fibrillation, and 3) in synchronization with the chest ECG, it also records heart sounds presented as a phonocardiogram making measurement of systolic time intervals possible. The sensitivity and specificity for detecting atrial fibrillation are high. The use of systolic time interval in patients with heart failure has so far not been evaluated.Expert opinion: The increasing use of long-term prescribed and privately owned handheld ECG devices for on-demand recording of heart rhythm will most probably cause a paradigm shift in arrhythmia diagnostics. Coala Heart Monitor´s use of both chest and thumb recordings as well as analyzing both RR-dispersion and P-wave morphology may offer an advantage in diagnosing atrial fibrillation.


Asunto(s)
Equipos y Suministros , Frecuencia Cardíaca/fisiología , Monitoreo Fisiológico/instrumentación , Algoritmos , Fibrilación Atrial/diagnóstico , Electrocardiografía/instrumentación , Humanos
13.
PLoS One ; 15(2): e0229519, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32097438

RESUMEN

BACKGROUND: Measures of cardiac ventricular electrophysiology have been associated with cognitive performance in cross-sectional studies. We sought to evaluate the association of worsening ventricular repolarization in midlife, as measured by incident prolonged QT interval, with cognitive decline in late life. METHODS: Midlife QT interval was assessed by electrocardiography during three study visits from 1965/68 to 1971/74 in a cohort of Japanese American men aged 46-68 at Exam 1 from the Honolulu Heart Study. We defined incident prolonged QT as the QT interval in the upper quartile at Exam 2 or 3 after QT interval in lower three quartiles at Exam 1. Cognitive performance was assessed at least once using the Cognitive Abilities Screening Instrument (CASI), scored using item response theory (CASI-IRT), during four subsequent visits from 1991/93 to 1999/2000 among 2,511 of the 4,737 men in the Honolulu-Asia Aging Study otherwise eligible for inclusion in analyses. We used marginal structural modeling to determine the association of incident prolonged QT with cognitive decline, using weighting to account for confounding and attrition. RESULTS: Incident prolonged QT interval in midlife was not associated with late-life CASI-IRT at cognitive baseline (estimated difference in CASI-IRT: 0.04; 95% CI: -0.28, 0.35; p = 0.81), or change in CASI-IRT over time (estimated difference in annual change in CASI-IRT: -0.002; 95%CI: -0.013, 0.010; p = 0.79). Findings were consistent across sensitivity analyses. CONCLUSIONS: Although many midlife cardiovascular risk factors and cardiac structure and function measures are associated with late-life cognitive decline, incident prolonged QT interval in midlife was not associated with late-life cognitive performance or cognitive decline.


Asunto(s)
Cognición/fisiología , Frecuencia Cardíaca/fisiología , Contracción Miocárdica/fisiología , Anciano , Envejecimiento , Americanos Asiáticos , Electrofisiología Cardíaca/métodos , Trastornos del Conocimiento/fisiopatología , Disfunción Cognitiva/complicaciones , Estudios de Cohortes , Estudios Transversales , Humanos , Hipertensión/complicaciones , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos
14.
Einstein (Sao Paulo) ; 18: eAO5227, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32022106

RESUMEN

OBJECTIVE: To investigate the efficacy of a behavior change program named Vida Ativa Melhorando a Saúde on cardiovascular parameters in hypertensive patients. METHODS: Ninety hypertensive patients aged over 40 years were randomly allocated to one of two groups: Vida Ativa Melhorando a Saúde or Control (n=45 respectively). Patients in the Vida Ativa Melhorando a Saúde group took part in a behavior change program aimed to encourage changes in physical activity levels and eating habits, according to the Social Cognitive Theory. The program consisted of 90-minute weekly group meetings conducted by a physical therapist and a dietitian. One chapter of the educational material (workbook) provided was discussed per meeting. Participants in the Control Group attended a single educative lecture on lifestyle changes. Brachial and central blood pressure, arterial stiffness and endothelial function parameters were measured pre- and post-intervention. RESULTS: Vida Ativa Melhorando a Saúde led to reduction of brachial (131.3±15.8mmHg to 125.1±17.3mmHg; p<0.01) and central (123.6±16.3mmHg to 119.0±20.6mmHg; p=0.02) systolic and brachial diastolic (123.6±16.3mmHg to 119.0±20.6mmHg; p<0.01) blood pressure values, and improvement of post-occlusive reactive hyperemia (from 5.7±2.5mL·100mL-1 to 6.5±2.1mL·100mL-1 tissue·min-1; p=0.04). No changes in body composition, heart rate and arterial stiffness parameters were detected in both groups (p>0.05). CONCLUSION: Vida Ativa Melhorando a Saúde program improved blood pressure and microvascular reactivity in hypertensive patients. Trial registration: ClinicalTrials.gov: NCT02257268.


Asunto(s)
Conductas Relacionadas con la Salud/fisiología , Hipertensión/fisiopatología , Anciano , Presión Sanguínea/fisiología , Composición Corporal , Ejercicio Físico/fisiología , Conducta Alimentaria/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Hiperemia/fisiopatología , Hipertensión/psicología , Estilo de Vida , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Resultado del Tratamiento , Rigidez Vascular/fisiología
15.
J Physiol Anthropol ; 39(1): 4, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32085811

RESUMEN

BACKGROUND: Recently, attempts have been made to use the pulse rate variability (PRV) as a surrogate for heart rate variability (HRV). PRV, however, may be caused by the fluctuations of left ventricular pre-ejection period and pulse transit time besides HRV. We examined whether PRV differs not only from HRV but also depending on the measurement site. RESULTS: In five healthy subjects, pulse waves were measured simultaneously on both wrists and both forearms together with single-lead electrocardiogram (ECG) in the supine and sitting positions. Although average pulse interval showed no significant difference from average R-R interval in either positions, PRV showed greater power for the low-frequency (LF) and high-frequency (HF) components and lower LF/HF than HRV. The deviations of PRV from HRV in the supine and sitting positions were 13.2% and 7.9% for LF power, 24.5% and 18.3% for HF power, and - 15.0% and - 30.2% for LF/HF, respectively. While the average pulse interval showed 0.8% and 0.5% inter-site variations among the four sites in the supine and sitting positions, respectively, the inter-site variations in PRV were 4.0% and 3.6% for LF power, 3.8% and 4.7% for HF power, and 18.0% and 17.5% for LF/HF, respectively. CONCLUSIONS: These suggest that PRV shows not only systemic differences from HRV but also considerable inter-site variations.


Asunto(s)
Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Análisis de la Onda del Pulso/métodos , Dispositivos Electrónicos Vestibles , Adulto , Femenino , Antebrazo/irrigación sanguínea , Humanos , Masculino , Postura/fisiología , Procesamiento de Señales Asistido por Computador , Muñeca/irrigación sanguínea , Adulto Joven
16.
PLoS One ; 15(2): e0227709, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32023264

RESUMEN

BACKGROUND: Heart rate is routinely measured as part of the clinical examination but is rarely acted upon unless it is well outside a population-based normal range. With wearable sensor technologies, heart rate can now be continuously measured, making it possible to accurately identify an individual's "normal" heart rate and potentially important variations in it over time. Our objective is to describe inter- and intra-individual variability in resting heart rate (RHR) collected over the course of two years using a wearable device, studying the variations of resting heart rate as a function of time of year, as well as individuals characteristics like age, sex, average sleep duration, and body mass index (BMI). METHODS AND FINDINGS: Our retrospective, longitudinal cohort study includes 92,457 de-identified individuals from the United States (all 50 states), who consistently-over at least 35 weeks in the period from March 2016 to February 2018, for at least 2 days per week, and at least 20 hours per day-wore a heart rate wrist-worn tracker. In this study, we report daily RHR and its association with age, BMI, sex, and sleep duration, and its variation over time. Individual daily RHR was available for a median of 320 days, providing nearly 33 million daily RHR values. We also explored the range in daily RHR variability between individuals, and the long- and short-term changes in the trajectory of an individual's daily RHR. Mean daily RHR was 65 beats per minute (bpm), with a range of 40 to 109 bpm among all individuals. The mean RHR differed significantly by age, sex, BMI, and average sleep duration. Time of year variations were also noted, with a minimum in July and maximum in January. For most subjects, RHR remained relatively stable over the short term, but 20% experienced at least 1 week in which their RHR fluctuated by 10 bpm or more. CONCLUSIONS: Individuals have a daily RHR that is normal for them but can differ from another individual's normal by as much as 70 bpm. Within individuals, RHR was much more consistent over time, with a small but significant seasonal trend, and detectable discrete and infrequent episodes outside their norms.


Asunto(s)
Índice de Masa Corporal , Frecuencia Cardíaca/fisiología , Descanso/fisiología , Estaciones del Año , Sueño/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores Sexuales , Adulto Joven
17.
Am J Physiol Heart Circ Physiol ; 318(3): H581-H589, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32004082

RESUMEN

Preeclampsia is associated with the development of cardiovascular diseases later in life. To investigate this phenomenon, we compared established markers of cardiovascular dysregulation between previously preeclamptic women (PPE; n = 12, 13 ± 6 mo postpartum, 34 ± 6 yr) and women who had previously had an uncomplicated pregnancy [control (CTRL); n = 12, 15 ± 4 mo postpartum; 29 ± 3 yr]. We hypothesized that PPE would present with elevated arterial stiffness (assessed as central and peripheral pulse wave velocity) and muscle sympathetic nerve activity (MSNA; microneurography) and blunted baroreflex sensitivity (BRS) relative to CTRL. Blood pressure (Finometer) was similar between PPE and CTRL (mean arterial pressure: 94 ± 11 vs. 89 ± 9, P = 0.16). Central (6.92 ± 0.21 vs. 6.24 ± 0.22 m/s, P = 0.04) but not peripheral arterial stiffness (7.52 ± 0.19 vs. 7.09 ± 0.19 m/s, P = 0.13) was elevated in PPE versus CTRL (values normalized to MAP). MSNA was also elevated in PPE versus CTRL (22 ± 7 vs. 13 ± 5 bursts/min, P = 0.01), although this was independent of arterial stiffness (central: r2 = 0.01, P = 0.74; peripheral: r2 = 0.01, P = 0.74). Cardiovagal BRS was blunted in PPE versus CTRL (15 ± 5 vs. 28 ± 1 ms/mmHg, P = 0.01), whereas sympathetic vascular BRS was similar (-3.2 ± 0.9 vs. -3.1 ± 1.4 bursts·100 hb-1·mmHg-1, P = 0.88). Cardiovagal and sympathetic BRS were inversely correlated in both CTRL (r2 = 0.43; P = 0.05) and PPE (r2 = 0.69; P = 0.04), supporting a compensatory mechanism resulting in normal blood pressures in both groups. Overall, these data indicate that PPE retain their ability to buffer elevated MSNA. We propose that the higher incidence of cardiovascular disease observed later in life in PPE results from this arterial stiffness, combined with the loss of protective vascular mechanisms and the "unmasking" of high MSNA.NEW & NOTEWORTHY We demonstrate that resting muscle sympathetic nerve activity is elevated in women with a recent history of preeclampsia relative to women who have recently had uncomplicated pregnancies and without a history of preeclampsia. Structural changes in the central arteries are associated with arterial stiffness following preeclampsia, independent of changes in the sympathetic nervous system. The structural changes are observed in these relatively young previously preeclamptic women, indicating elevated cardiovascular risk. Our data suggest that with aging (and the gradual loss of vascular protection for women, as established by others), this risk will become exaggerated compared with women who have had normal pregnancies.


Asunto(s)
Músculo Esquelético/inervación , Preeclampsia/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Rigidez Vascular/fisiología , Adulto , Barorreflejo/fisiología , Biomarcadores/sangre , Presión Sanguínea/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Hemodinámica/fisiología , Humanos , Músculo Esquelético/fisiopatología , Embarazo , Análisis de la Onda del Pulso
18.
Int J Sports Med ; 41(2): 82-88, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31902128

RESUMEN

Sex differences exist in vascular responses to blood pressure perturbations, such as resistance exercise. Increases in aortic stiffness following acute resistance exercise appear different between sexes, with attenuated increases in females vs. males. Whether sex differences exist in carotid stiffness, following resistance exercise is unknown. This study sought to examine sex differences in carotid stiffness, aortic stiffness, and hemodynamics following acute resistance exercise. Thirty-five participants (18 male) completed 3 sets of 10 repetitions of maximal isokinetic knee extension/flexion. Aortic stiffness and hemodynamics were estimated using an automated oscillometric blood pressure monitor at baseline, 5- and 30-min post-exercise. Carotid stiffness was assessed by ß-stiffness index, pressure-strain elastic modulus and arterial compliance using ultrasonography. Resistance exercise increased aortic stiffness, mean and systolic pressure at 5-min (p<0.01), and pressure-strain elastic modulus at 5-min in both sexes (p<0.05). Arterial compliance decreased at 5- and 30-min post exercise in both sexes (p<0.01). No interaction effects were detected in carotid stiffness, aortic stiffness, and hemodynamics, indicating similar vascular responses between sexes. Our findings indicate that the large arteries appear to stiffen similarly following resistance exercise in males and females when presented with similar blood pressure responses.


Asunto(s)
Arterias Carótidas/fisiología , Entrenamiento de Resistencia , Rigidez Vascular/fisiología , Adulto , Presión Sanguínea/fisiología , Composición Corporal , Módulo de Elasticidad/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Rodilla/fisiología , Masculino , Fuerza Muscular/fisiología , Factores Sexuales , Adulto Joven
19.
Anim Cogn ; 23(2): 389-403, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31907679

RESUMEN

Rescue behavior is considered a type of pro-social response, defined as a voluntary action directed to benefit another individual who is in a stressful or dangerous situation. In two experiments, we investigated whether dogs would rescue their owners when the person was trapped inside a wooden box and emitted clear signs of stress. The performance of these dogs was compared against that of a control group in which the owners remained calm while trapped. In addition, to assess if training modulated this behavior, we tested a group of dogs from the military trained in search and rescue tasks (Experiment 1). Results showed that dogs opened the box more frequently when the owner pretended to be stressed than when calm. Training shortened latencies to open the door but not the frequency of the behavior. In Experiment 2, we investigated if emotional contagion could be a possible mechanism underlying dogs' rescue responses by measuring dogs' behavior, heart rate, and saliva cortisol level in the stressed and calm conditions, and also controlled for obedience by having the calm owners call their pets while trapped. We replicated the findings of Experiment 1 as more dogs opened the door in the stressed owner condition than in the calm condition. In addition, we observed an increase in heart rate across trials in the stressed condition and a decrease across trials in the calm condition, but no differences in cortisol levels or stress-related behaviors between conditions. In brief, we found evidence that approximately half of the dogs without previous training showed spontaneous rescue behaviors directed to their owners. Neither was this behavior motivated by obedience nor by the motivation to re-establish social contact with the owner. We conclude that emotional contagion is a plausible mechanism underlying dogs' rescue behavior in the present protocol.


Asunto(s)
Conducta Animal , Vínculo Ser Humano-Animal , Estrés Psicológico , Animales , Conducta Animal/fisiología , Perros , Emociones , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Motivación , Saliva
20.
J Sports Sci ; 38(5): 576-581, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31992141

RESUMEN

The purpose of this study was to explore the respiratory response of acute interval and continuous exercise (CE) of low and high intensity. Fourteen recreational athletes (7 men and 7 women; VO2max = 35.7 ± 6.1 mlkg-1min-1) performed a bout of continuous and a bout of interval exercise (IE) both consisted of 5-min cycling at low intensity [80% of the power output (W) of the predetermined gas exchange threshold (GET) (80%WGET)] and 5-min cycling at high intensity {WGET plus the work rate corresponding to 50% of the difference between peak power output (PPO) at oxygen uptake (VO2max) test and the WGET [WGET + 0.50 Δ(PPO - WGET)]}. CE compared to IE induced significant higher heart rate and ventilation as well as significant higher levels of mouth occlusion pressure for 0.1 s (P0.1) (P < 0.05) during low and high intensities. Our results indicate that CE stimulates respiration more than IE when the exercise is performed at the same relative intensity.


Asunto(s)
Atletas , Ejercicio Físico/fisiología , Respiración , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Consumo de Oxígeno , Intercambio Gaseoso Pulmonar/fisiología , Adulto Joven
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