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1.
Public Health ; 204: 14-20, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35121569

RESUMEN

OBJECTIVES: This study aimed to examine the changes in depression and anxiety symptoms among Brazilian adults over 10 months of the COVID-19 pandemic. STUDY DESIGN/METHODS: The present study used data from wave 1 (June/July 2020) and wave 2 (December 2020/January 2021) of the Prospective Study About Mental and Physical Health (PAMPA) Cohort, a state-level, ambispective longitudinal study with adults from southern Brazil. The frequency of anxiety and depressive symptoms was assessed using the Hospital Anxiety and Depression Scale. Anxiety and depressive symptoms before social distancing were retrospectively assessed during wave 1. RESULTS: Most of the 674 participants were classified as non-symptomatic for depressive (85.0%) and anxiety symptoms (73.2%) before the COVID-19 pandemic. At wave 1, there were increases in symptoms of depression (7.6% [95% confidence interval [CI]: 7.2%, 8.1%]) and anxiety (9.1% [95% CI: 8.6%, 9.5%]). These decreased at wave 2 (depression: 6.9% [95% CI: 6.5%, 7.2%]; anxiety: 7.4% [95% CI: 7.1%, 7.8%]) although they were still elevated compared with pre-COVID (depression: 4.5% [95% CI: 4.2%, 4.8%]; anxiety: 5.8% [95% CI: 5.5%, 6.1%]). Adults living alone (b = 0.44 [95% CI: 0.07, 0.82]) had a faster trajectory in anxiety symptoms than their counterparts. Cohort members who were living alone (b = 0.24 [95% CI: 0.06, 0.42]) and with diagnosed chronic disease (0.32 [95% CI: 0.18, 0.46]) had a faster increase in depressive symptoms than their respective counterparts. Participants aged ≥60 years showed a slower trajectory of depressive (b = -0.46 [95% CI: -0.73, -0.18]) and anxiety (b = -0.61 [95% CI: -1.20, -0.02) symptoms. CONCLUSIONS: During 10 months of COVID-19, anxiety and depression symptoms improved but were still higher than before COVID-19.


Asunto(s)
COVID-19 , Adulto , Ansiedad/epidemiología , Brasil/epidemiología , COVID-19/epidemiología , Depresión/epidemiología , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Pandemias , Estudios Prospectivos , Estudios Retrospectivos , SARS-CoV-2
2.
Public Health ; 190: 101-107, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33387848

RESUMEN

OBJECTIVES: We aimed to compare the prevalence of depression and anxiety symptoms before and during the pandemic and identify factors associated with aggravated mental health symptoms. STUDY DESIGN: Retrospective cohort study. METHODS: We identified the proportion of normal, mild, moderate, and severe symptoms of depression and anxiety before and during the social distancing restrictions in adults from southern Brazil. An online, self-administered questionnaire was delivered for residents within the state of Rio Grande do Sul. Depressive and anxiety symptoms were examined by the Hospital Anxiety and Depression Scale. RESULTS: Most of the participants (n = 2314) aged between 31 and 59 years (54.2%), were women (76.6%), White (90.6%) with a university degree (66.6%). Moderate-to-severe symptoms of depression and anxiety were reported in 3.9% and 4.5% of participants, respectively, before COVID-19. During the pandemic (June-July, 2020), these proportions increased to 29.1% (6.6-fold increase) and 37.8% (7.4-fold increase), respectively. Higher rates of depressive and anxiety symptoms were observed among women, those aged 18-30 years, diagnosed with chronic disease and participants who had their income negatively affected by social restrictions. Remaining active or becoming physically active during social distancing restrictions reduced the probability of aggravated mental health disorders. CONCLUSIONS: Depressive and anxiety symptoms had a 6.6- and 7.4-fold increase since the COVID-19 pandemic. Public policies such as physical activity promotion and strategies to reduce the economic strain caused by this pandemic are urgently needed to mitigate the impact of the pandemic on mental health.


Asunto(s)
Ansiedad/epidemiología , COVID-19/psicología , Depresión/epidemiología , Salud Mental/estadística & datos numéricos , SARS-CoV-2 , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/etiología , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Brasil/epidemiología , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/prevención & control , Estudios de Cohortes , Depresión/etiología , Femenino , Humanos , Renta , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pandemias , Prevalencia , Estudios Retrospectivos , Encuestas y Cuestionarios , Adulto Joven
3.
Scand J Med Sci Sports ; 25 Suppl 1: 112-25, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25943662

RESUMEN

Athletes use intravenous (IV) saline in an attempt to maximize rehydration. The diuresis from IV rehydration may be circumvented through the concomitant use of oral glycerol. We examined the effects of rehydrating with differing regimes of oral and IV fluid, with or without oral glycerol, on hydration, urine, and endocrine indices. Nine endurance-trained men were dehydrated by 4% bodyweight, then rehydrated with 150% of the fluid lost via four protocols: (a) oral = oral fluid only; (b) oral glycerol = oral fluid with added glycerol (1.5 g/kg); (c) IV = 50% IV fluid, 50% oral fluid; and (d) IV with oral glycerol = 50% IV fluid, 50% oral fluid with added glycerol (1.5 g/kg), using a randomized, crossover design. They then completed a cycling performance test. Plasma volume restoration was highest in IV with oral glycerol > IV > oral glycerol > oral. Urine volume was reduced in both IV trials compared with oral. IV and IV with oral glycerol resulted in lower aldosterone levels during rehydration and performance, and lower cortisol levels during rehydration. IV with oral glycerol resulted in the greatest fluid retention. In summary, the IV conditions resulted in greater fluid retention compared with oral and lower levels of fluid regulatory and stress hormones compared with both oral conditions.


Asunto(s)
Aldosterona/metabolismo , Deshidratación/terapia , Fluidoterapia/métodos , Glicerol/uso terapéutico , Hidrocortisona/metabolismo , Soluciones para Rehidratación/uso terapéutico , Equilibrio Hidroelectrolítico , Adolescente , Adulto , Biomarcadores/metabolismo , Estudios Cruzados , Deshidratación/metabolismo , Deshidratación/fisiopatología , Ingestión de Líquidos , Humanos , Infusiones Intravenosas , Masculino , Volumen Plasmático , Estrés Fisiológico/fisiología , Resultado del Tratamiento , Adulto Joven
4.
Int J Sports Med ; 35(1): 8-13, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23839729

RESUMEN

This study examined the influence of training volume on resting and exercise-induced plasma markers of oxidative stress (MDA concentration) and antioxidant status (GPX, CAT & SOD erythrocyte activities). Moderately trained participants (TG) (n=6; 4 males and 2 females; 25±1.8 years) and sedentary control subjects (CG) participated in the 8-week investigation. The TG increased their training volume from ~4.9 to ~18 h.wk-1 by the end of the investigation. Before the increase in training volume and at 2-week intervals the TG completed a 30 km cycling time trial (TT30) where resting-and post-exercise blood was -sampled and analysed for oxidative stress and antioxidant status. The CG had their resting blood sampled and analysed fortnightly. The data showed that TT30 performance improved in the first 4 weeks but remained unchanged in the last 4. Resting plasma MDA and CAT increased in response to training, with no change in the resting activities of erythrocyte GPX and SOD. Post-TT30 MDA and CAT increased over the training period and training hours positively related to both resting-and post-TT30 MDA. The increase in resting MDA and the up-regulation in CAT in response to an increased training volume may have a role in the identification of a training and performance plateau.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Estrés Oxidativo/fisiología , Adulto , Antioxidantes/metabolismo , Biomarcadores/sangre , Eritrocitos/metabolismo , Prueba de Esfuerzo , Femenino , Glutatión Peroxidasa/sangre , Humanos , Masculino , Malondialdehído/sangre , Superóxido Dismutasa/sangre
5.
J Sports Med Phys Fitness ; 53(5): 490-501, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23903529

RESUMEN

AIM: The aim of this pilot investigation was to examine the influence of bovine colostrum protein concentrate (CPC) supplementation on salivary hormones, salivary IgA and heart rate variability over consecutive days of competitive cycling. METHODS: Ten highly-trained male road cyclists (mean±SEM; age=22.2±4.7 yr; mass=70.5±4.5 kg; VO2max=72.9±3.8 mL.kg-1.min-1) were randomly assigned to a control (N.=6, 10g whey protein concentrate/day) or bovine CPC group (N.=4, 10 g bovine CPC/day). Cyclists provided a baseline saliva sample before commencing eight weeks of supplementation, and competing in a five day cycle race. Cyclists provided saliva samples and measured heart rate variability (HRV) each day of the race. Saliva samples were analysed for cortisol, testosterone and IgA concentrations. RESULTS: Bovine CPC supplementation was associated with increased morning cortisol concentration on the first day of racing when compared to the control group (P=0.004) and significantly prevented a decrease in testosterone concentration over the race period (P≤0.05). Across the race period parasympathetic indices of HRV were elevated in the bovine CPC group and reduced in the control group (P≤0.05), while there were no significant differences in salivary IgA between groups. CONCLUSION: Bovine CPC supplementation maintained salivary testosterone concentration and modulated autonomic activity over consecutive days of competitive cycling. This pilot study provides justification to explore the effects of bovine CPC on recovery in endurance athletes further.


Asunto(s)
Sistema Nervioso Autónomo/efectos de los fármacos , Ciclismo/fisiología , Calostro , Suplementos Dietéticos , Hidrocortisona/sangre , Resistencia Física/fisiología , Testosterona/sangre , Animales , Sistema Nervioso Autónomo/fisiología , Bovinos , Estudios de Seguimiento , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Inmunoglobulina A/sangre , Masculino , Proyectos Piloto , Saliva/química , Adulto Joven
6.
Eur J Sport Sci ; 23(4): 530-541, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35107058

RESUMEN

Exercise is positively associated with higher microbial diversity, but there is limited information on exercise intensity's effect on gut microbiome composition and function in clinical populations. This study examines whether different intensities of exercise exert differential effects on gut microbiome composition and function in low active people with type 2 diabetes. This is a sub-study of the Exercise for Type 2 Diabetes Study, a single centre, prospective, randomised controlled trial. Participants (n = 12) completed 8-weeks of combined aerobic and resistance moderate intensity continuous training (C-MICT) or combined aerobic and resistance high-intensity interval training (C-HIIT). Faecal samples were collected before and after intervention to measure gut microbiome composition and metabolic pathways (metagenome shotgun sequencing) and short-chain fatty acids. Post-exercise α-diversity was different between groups as was the relative abundance of specific taxa was (p < .05). Post-exercise relative abundance of Bifidobacterium, A. municiphila, and butyrate-producers Lachnospira eligens, Enterococcus spp., and Clostridium Cluster IV were higher at lower exercise intensity. Other butyrate-producers (from Eryspelothrichales and Oscillospirales), and methane producer Methanobrevibacter smithii were higher at higher exercise intensity. Pyruvate metabolism (ko00620),COG "Cell wall membrane envelope biogenesis" and "Unknown function" pathways were significantly different between groups and higher in C-MICT post-exercise. Differential abundance analysis on KO showed higher expression of Two-component system in C-HIIT. Transcription factors and "unknown metabolism" related pathways decreased in both groups. There were no significant between group changes in faecal short chain fatty acids. Exercise intensity had a distinct effect on gut microbiome abundance and metabolic function, without impacting short-chain fatty acid output.HighlightsEvidence of exercise effect on gut microbiome outcomes is limited to healthy and athletic populationsIn low active people with type 2 diabetes, different exercise intensities increased specific health promoting and butyrate producers species, and showed differentially abundant gut microbiome metabolic pathways.Further investigation is warranted, and if this supports the present findings, then specific exercise intensities may be promoted to target specific species and optimise gut health.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Estudios Prospectivos , Ejercicio Físico , Butiratos
7.
Int J Obes (Lond) ; 36(1): 93-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21487397

RESUMEN

BACKGROUND: Body size is associated with increased brachial systolic blood pressure (SBP) and aortic stiffness. The aims of this study were to determine the relationships between central SBP and body size (determined by body mass index (BMI), waist circumference and waist/hip ratio) in health and disease. We also sought to determine if aortic stiffness was correlated with body size, independent of BP. METHODS: BMI, brachial BP and estimated central SBP (by SphygmoCor and radial P2) were recorded in controls (n=228), patients with diabetes (n=211), coronary artery disease (n=184) and end-stage kidney disease (n=68). Additional measures of waist circumference and arterial stiffness (aortic and brachial pulse wave velocity (PWV)) were recorded in a subgroup of 75 controls (aged 51 ± 12 years) who were carefully screened for factors affecting vascular function. RESULTS: BMI was associated with brachial (r=0.30; P<0.001) and central SBP (r=0.29; P<0.001) in the 228 controls, but not the patient populations (r<0.13; P>0.15 for all comparisons). In the control subgroup, waist circumference was also significantly correlated with brachial SBP (r=0.29; P=0.01), but not central SBP (r=0.22; P=0.07). Independent predictors of aortic PWV in the control subgroup were brachial SBP (ß=0.43; P<0.001), age (ß=0.37; P<0.001), waist circumference (ß=0.39; P=0.02) and female sex (ß=-0.24; P=0.03), but not BMI. CONCLUSION: In health, there are parallel increases in central and brachial SBP as BMI increases, but these relationships are not observed in the presence of chronic disease. Moreover, BP is a stronger correlate of arterial stiffness than body size.


Asunto(s)
Presión Sanguínea , Índice de Masa Corporal , Enfermedades Cardiovasculares/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Fallo Renal Crónico/fisiopatología , Rigidez Vascular , Velocidad del Flujo Sanguíneo , Arteria Braquial/fisiopatología , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/epidemiología , Enfermedad Crónica , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Ecocardiografía , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/epidemiología , Masculino , Manometría , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Flujo Pulsátil , Factores de Riesgo , Esfigmomanometros , Circunferencia de la Cintura , Relación Cintura-Cadera
8.
Diabet Med ; 29(7): e33-40, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22172021

RESUMEN

AIMS: Heart rate variability may be used to assess diabetic cardiac autonomic neuropathy. The aim of the present study was to determine the reliability of standard short-term clinical measurements of heart rate variability in patients with Type 2 diabetes. METHODS: In 24 patients with Type 2 diabetes (11 male, age 61 ± 9 years), parameters of heart rate variability in the time domain (standard deviation of RR intervals, coefficient of variation of RR intervals and root mean square of successive RR interval differences) and frequency domain (very low frequency, low frequency, high frequency and total spectral power) were derived from a 5-min electrocardiograph recorded during two laboratory visits separated by 16 ± 8 days. Absolute and relative reliability were assessed by 95% limits of random variation and the intraclass correlation coefficient, respectively. Categorical agreement of classifications of heart rate variability and sample size estimates for clinical trials were calculated. RESULTS: Despite no significant difference in mean heart rate variability between tests, 95% limits of random variation indicated that repeated measurements were between 58% higher/37% lower (most reliable parameter; coefficient of variation of RR intervals) and 443% higher/82% lower (least reliable parameter; very low frequency power) than the first measure. The intraclass correlation coefficient ranged from 0.58 to 0.90 and sample size requirements from 20 to 93 patients per group. Agreement of categories of heart rate variability ranged from 79 to 96%. CONCLUSIONS: Short-term clinical measurements of heart rate variability in patients with Type 2 diabetes are characterized by poor absolute reliability, but substantial to good relative reliability, suggesting greater clinical utility in diagnosis than in sequential follow-up.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Neuropatías Diabéticas/fisiopatología , Electrocardiografía/métodos , Frecuencia Cardíaca , Anciano , Análisis de Varianza , Interpretación Estadística de Datos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/sangre , Neuropatías Diabéticas/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Tiempo
9.
Diabet Med ; 29(9): e312-20, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22671998

RESUMEN

AIMS: Poor prognosis associated with blunted post-exercise heart-rate recovery may reflect autonomic dysfunction. This study sought the accuracy of post-exercise heart-rate recovery in the diagnosis of cardiac autonomic neuropathy, which represents a serious, but often unrecognized complication of Type 2 diabetes. METHODS: Clinical assessment of cardiac autonomic neuropathy and maximal treadmill exercise testing for heart-rate recovery were performed in 135 patients with Type 2 diabetes and negative exercise echocardiograms. Cardiac autonomic neuropathy was defined by abnormalities in ≥ 2 of 7 autonomic function markers, including four cardiac reflex tests and three indices of short-term (5-min) heart-rate variability. Heart-rate recovery was defined at 1-, 2- and 3-min post-exercise. RESULTS: Patients with cardiac autonomic neuropathy (n = 27; 20%) had lower heart-rate recovery at 1-, 2- and 3-min post-exercise (P < 0.01). Heart-rate recovery demonstrated univariate associations with autonomic function markers (r-values 0.20-0.46, P < 0.05). Area under the receiver-operating characteristic curve revealed good diagnostic performance of all heart-rate recovery parameters (range 0.80-0.83, P < 0.001). Optimal cut-offs for heart-rate recovery at 1-, 2- and 3-min post-exercise were ≤ 28 beats/min (sensitivity 93%, specificity 69%), ≤ 50 beats/min (sensitivity 96%, specificity 63%) and ≤ 52 beats/min (sensitivity 70%, specificity 84%), respectively. These criteria predicted cardiac autonomic neuropathy independently of relevant clinical and exercise test information (adjusted odds ratios 7-28, P < 0.05). CONCLUSIONS: Post-exercise heart-rate recovery provides an accurate diagnostic test for cardiac autonomic neuropathy in Type 2 diabetes. The high sensitivity and modest specificity suggests heart-rate recovery may be useful to screen for patients requiring clinical autonomic evaluation.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Cardiomiopatías Diabéticas/diagnóstico , Neuropatías Diabéticas/diagnóstico , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Tamizaje Masivo/métodos , Anciano , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Cardiomiopatías Diabéticas/epidemiología , Neuropatías Diabéticas/epidemiología , Electrocardiografía , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Curva ROC , Factores de Riesgo , Sensibilidad y Especificidad , Factores de Tiempo
10.
Panminerva Med ; 51(3): 151-61, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19859050

RESUMEN

Patients on peritoneal dialysis have a high level of morbidity and mortality associated with atherosclerotic cardiovascular disease and they also have an increased risk of sudden death. The atherosclerosis seen in peritoneal dialysis patients is associated with both traditional cardiovascular risk factors such as low levels of physical activity, hyperlipidemia, hypertension, diabetes and smoking as well as non-traditional risk factors such as elevated oxidative stress and inflammation. The atherosclerosis may be preceded by endothelial dysfunction and increased arterial stiffness. Measures of arterial stiffness such as aortic pulse wave velocity predict morbidity and mortality. Numerous studies have reported that the elevated levels of oxidative stress and inflammation in this population are associated with arterial stiffness and in turn with the development of cardiovascular disease. A number of studies have reported that peritoneal dialysis is associated with lower levels of oxidative stress and inflammation compared to haemodialysis. A small number of trials have extended this work to determine associations between oxidative stress and inflammation with vascular or myocardial structure and function with equivocal results. The decision to undergo either peritoneal or haemodialysis is based on many factors which include the differential damage the renal replacement therapy may have on the cardiovascular system. Current evidence suggests this may vary over time. Previous randomised controlled trials and many other observational studies have produced conflicting results as to which therapy may have a cardiovascular advantage. Some registry data suggests peritoneal dialysis is associated with a lower mortality than haemodialysis in the first one-two years but thereafter may be higher on peritoneal dialysis than haemodialysis. Other registry data do not support this. Further long-term studies assessing surrogate and hard endpoint cardiovascular outcomes in peritoneal dialysis are required.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Renales/terapia , Diálisis Peritoneal/efectos adversos , Enfermedades Cardiovasculares/mortalidad , Medicina Basada en la Evidencia , Humanos , Enfermedades Renales/mortalidad , Diálisis Peritoneal/mortalidad , Diálisis Renal/efectos adversos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
13.
Mutat Res ; 629(2): 122-32, 2007 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-17350329

RESUMEN

The aim of this study was to explore the potential pro- and anti-mutagenic effects of endogenous bile pigments unconjugated bilirubin (BR), biliverdin (BV) and a synthetic, water soluble conjugate, bilirubin ditaurate (BRT) in the Ames Salmonella test. The bile pigments were tested over a wide concentration range (0.01-2 micromol/plate) in the presence of three bacterial strains (TA98, TA100, TA102). A variety of mutagens including benzo[alpha]pyrene (B[alpha]P), 2,4,7 trinitrofluorenone (TNFone), 2-aminofluorene (2-AF), sodium azide (NaN(3)) and tertiary-butyl hydroperoxide (t-BuOOH), were used to promote the formation of mutant revertants. Tests were conducted with (B[alpha]P, 2-AF, t-BuOOH) and without (TNFone, NaN(3), t-BuOOH) metabolic activation incorporating the addition of the microsomal liver preparation, S9. The bile pigments alone did not induce mutagenicity in any of the strains tested (p>0.05). Anti-mutagenic effects of the bile pigments were observed in the presence of all mutagens except for NaN(3) and the anti-mutagenic effects appeared independent of the strain tested. For TNFone induced genotoxicity, the order of effectiveness was BR> or =BRT>BV. However, the order was BV> or =BRT> or =BR for 2-AF. Antioxidant testing in the TA102 strain revealed bile pigments could effectively inhibit the genotoxic effect of t-BuOOH induced oxidative stress. The apparent antioxidant and anti-mutagenic behaviour of bile pigments further suggests their presence in biological systems is of possible physiological importance.


Asunto(s)
Antimutagênicos/farmacología , Antioxidantes/farmacología , Pigmentos Biliares/farmacología , Animales , Antimutagênicos/química , Antioxidantes/química , Pigmentos Biliares/química , Técnicas In Vitro , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Ratas , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
14.
J Sports Med Phys Fitness ; 47(3): 300-3, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17641596

RESUMEN

AIM: Maximal oxygen uptake (VO(2max)) cycling protocols usually require expensive laboratory ergometers where the athlete is unaccustomed to the cycling position. Recently, we developed a VO(2max) speed-ramped protocol with an indoor cycling simulator (Cateye Windtrainer WT) allowing cyclists to use their own bicycles during the VO(2max) test. The aim of this study was to test the validity of the WT protocol by comparing it with a traditional (TD) resistance-ramped protocol using an electronically braked ergometer. In addition, the retest reliability of the WT protocol was also determined. METHODS: Twenty experienced cyclists randomly completed 6 VO(2max) protocols consisting of one familiarization trial and two tests on the WT and TD protocols. RESULTS: There were minimal differences in maximal oxygen uptake values between protocols (WT 64.1+/-7.1, TD 63.3+/-7.4 mL/kg/min). The variability in the difference of the means between the two protocols was 0.8 mL/kg/min (95% confidence interval CI: -0.26-2.02), the coefficient of variation (CV) was 2.8% (95%CI: 2.2-4.2%) and the interclass correlation was r=0.94 (P<0.01; 95%CI: 0.86-0.98). The intratest difference within the WT protocol was 1.5% (95%CI: -1.9-5%), CV=5.3% (95%CI: 4.1-8%) and the retest correlation was r=0.81 (P<0.01; 95%CI: 0.57-0.92). CONCLUSION: The WT speed-ramped protocol is a valid and reliable method to assess VO(2max).


Asunto(s)
Ciclismo/fisiología , Consumo de Oxígeno , Adulto , Ergometría , Prueba de Esfuerzo , Frecuencia Cardíaca , Humanos , Masculino , Aptitud Física , Reproducibilidad de los Resultados
15.
Obes Rev ; 18(8): 943-964, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28513103

RESUMEN

Interval training (including high-intensity interval training [HIIT] and sprint interval training [SIT]) is promoted in both scientific and lay media as being a superior and time-efficient method for fat loss compared with traditional moderate-intensity continuous training (MICT). We evaluated the efficacy of HIIT/SIT when directly compared with MICT for the modulation of body adiposity. Databases were searched to 31 August 2016 for studies with exercise training interventions with minimum 4-week duration. Meta-analyses were conducted for within-group and between-group comparisons for total body fat percentage (%) and fat mass (kg). To investigate heterogeneity, we conducted sensitivity and meta-regression analyses. Of the 6,074 studies netted, 31 were included. Within-group analyses demonstrated reductions in total body fat (%) (HIIT/SIT: -1.26 [95% CI: -1.80; -0.72] and MICT: -1.48 [95% CI: -1.89; -1.06]) and fat mass (kg) (HIIT/SIT: -1.38 [95% CI: -1.99; -0.77] and MICT: -0.91 [95% CI: -1.45; -0.37]). There were no differences between HIIT/SIT and MICT for any body fat outcome. Analyses comparing MICT with HIIT/SIT protocols of lower time commitment and/or energy expenditure tended to favour MICT for total body fat reduction (p = 0.09). HIIT/SIT appears to provide similar benefits to MICT for body fat reduction, although not necessarily in a more time-efficient manner. However, neither short-term HIIT/SIT nor MICT produced clinically meaningful reductions in body fat.


Asunto(s)
Adiposidad/fisiología , Terapia por Ejercicio/métodos , Entrenamiento de Intervalos de Alta Intensidad/métodos , Obesidad/terapia , Sobrepeso/terapia , Pérdida de Peso/fisiología , Índice de Masa Corporal , Metabolismo Energético/fisiología , Humanos , Consumo de Oxígeno/fisiología , Resultado del Tratamiento
16.
Aliment Pharmacol Ther ; 46(8): 741-747, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28805258

RESUMEN

BACKGROUND: Patients with advanced liver disease may develop portal hypertension that can result in variceal haemorrhage. Beta-blockers reduce portal pressure and minimise haemorrhage risk. These medications may attenuate measures of cardiopulmonary performance, such as the ventilatory threshold and peak oxygen uptake measured via cardiopulmonary exercise testing. AIM: To determine the effect of beta-blockers on cardiopulmonary exercise testing variables in patients with advanced liver disease. METHODS: This was a cross-sectional analysis of 72 participants who completed a cardiopulmonary exercise test before liver transplantation. All participants remained on their usual beta-blocker dose and timing prior to the test. Variables measured during cardiopulmonary exercise testing included the ventilatory threshold, peak oxygen uptake, heart rate, oxygen pulse, the oxygen uptake efficiency slope and the ventilatory equivalents for carbon dioxide slope. RESULTS: Participants taking beta-blockers (n = 28) had a lower ventilatory threshold (P <.01) and peak oxygen uptake (P = .02), compared to participants not taking beta-blockers. After adjusting for age, the model of end-stage liver-disease score, liver-disease aetiology, presence of refractory ascites and ventilatory threshold remained significantly lower in the beta-blocker group (P = .04). The oxygen uptake efficiency slope was not impacted by beta-blocker use. CONCLUSIONS: Ventilatory threshold is reduced in patients with advanced liver disease taking beta-blockers compared to those not taking the medication. This may incorrectly risk stratify patients on beta-blockers and has implications for patient management before and after liver transplantation. The oxygen uptake efficiency slope was not influenced by beta-blockers and may therefore be a better measure of cardiopulmonary performance in this patient population.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Prueba de Esfuerzo/métodos , Hepatopatías/tratamiento farmacológico , Consumo de Oxígeno , Dióxido de Carbono , Estudios Transversales , Várices Esofágicas y Gástricas/tratamiento farmacológico , Femenino , Hemorragia Gastrointestinal/tratamiento farmacológico , Frecuencia Cardíaca , Humanos , Hepatopatías/complicaciones , Masculino , Persona de Mediana Edad
17.
Clin Nephrol ; 66(5): 373-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17140167

RESUMEN

BACKGROUND: Cyclosporin A (CsA)-treated renal transplant recipients (RTR) exhibit relative hyperhomocystinemia and vascular dysfunction. Folate supplementation lowers homocysteine and has been shown to improve vascular function in healthy subjects and patients with coronary artery disease. The aim of this study was to assess the effects of 3 months of folate supplementation (5 mg/day) on vascular function and structure in RTR. METHODS: A double-blind, placebo-controlled crossover study was conducted in 10 CsA-treated RTR. Vascular structure was measured as carotid artery intima media thickness (IMT) and function was assessed as changes in brachial artery diameter during reactive hyperemia (RH) and in response to glyceryl trinitrate (GTN). Function data were analyzed as absolute and percent change from baseline and area under the diameter/time curve. Blood samples were collected before and after supplementation and analyzed for total plasma homocysteine, folate, vitamin B12 and asymmetric dimethyl arginine (ADMA) in addition to regular measures of hemoglobin, hematocrit, mean corpuscular volume (MCV) and serum creatinine. RESULTS: Folate supplementation significantly increased plasma folate by 687% (p < 0.005) and decreased homocysteine by 37% (p < 0.05) with no changes (p > 0.05) in vitamin B12 or ADMA. There were no significant (p > 0.05) changes in vascular structure or function during the placebo or the folate supplementation phases; IMT; placebo pre mean +/- SD, 0.52 +/- 0.12, post 0.50 +/- 0.11; folate pre 0.55 +/- 0.17, post 0.49 +/- 0.20 mm, 5% change in brachial artery diameter (RH, placebo pre 10 +/- 8, post 6 +/- 5; folate pre 9 +/- 7, post 7 +/- 5; GTN, placebo pre 18 +/- 10, post 17 +/- 9, folate pre 16 +/- 9, post-supplementation 18 +/- 8). CONCLUSION: Three months of folate supplementation decreases plasma homocysteine but has no effect on endothelial function or carotid artery IMT in RTR.


Asunto(s)
Arteria Braquial/efectos de los fármacos , Arterias Carótidas/efectos de los fármacos , Ciclosporina/uso terapéutico , Ácido Fólico/uso terapéutico , Inmunosupresores/uso terapéutico , Trasplante de Riñón , Túnica Íntima/efectos de los fármacos , Túnica Media/efectos de los fármacos , Arteria Braquial/patología , Arterias Carótidas/patología , Estudios Cruzados , Ciclosporina/sangre , Método Doble Ciego , Femenino , Ácido Fólico/sangre , Homocisteína/sangre , Homocisteína/efectos de los fármacos , Humanos , Inmunosupresores/sangre , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Túnica Íntima/patología , Túnica Media/patología
18.
Int J Clin Pharmacol Ther ; 44(11): 580-8, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17176625

RESUMEN

OBJECTIVE: Previous studies investigating associations between serum lipids and renal disease have generally not taken into account dietary intake or physical activity both known to influence circulating lipids. Furthermore, inclusion of patients on HMG-CoA reductase inhibitors may also have influenced findings due to the pleiotropic effect of this medication. Therefore, the aim of this study is to determine the relationships between serum lipids and renal function in a group of patients not taking lipid-lowering medication and taking into account dietary intake and physical activity. METHODS: Data from 100 patients enrolled in the Lipid Lowering and Onset of Renal Disease (LORD) trial were used in this study. Patients were included with serum creatinine > 120 micromol/l, and excluded if they were taking lipid-lowering medication. Unadjusted and adjusted relationships were determined between fasting serum lipid concentrations (total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol/HDL ratio) and measures of renal function (estimated glomerular filtration rate (eGFR), creatinine clearance and serum creatinine) and urinary protein excretion. RESULTS: Significant (p < 0.05) negative unadjusted relationships were found between lipids (total cholesterol, LDL and HDL cholesterol) and serum creatinine. In support of these findings, logarithmically-transformed lipids (total cholesterol, LDL and HDL cholesterol) were significantly associated with eGFR and creatinine clearance although the effects were of a smaller magnitude. Adjustment for dietary saturated fat intake and physical activity did not substantially change these effects. CONCLUSION: These data do not support the premise that lipids are associated with renal dysfunction in patients with normocholesterolemia.


Asunto(s)
Enfermedades Renales/fisiopatología , Lípidos/sangre , Presión Sanguínea , Creatinina/sangre , Dieta , Método Doble Ciego , Femenino , Tasa de Filtración Glomerular , Humanos , Enfermedades Renales/sangre , Enfermedades Renales/orina , Masculino , Persona de Mediana Edad , Actividad Motora , Proteinuria
19.
Br J Sports Med ; 40(9): 797-801, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16825268

RESUMEN

PURPOSE: The aim of this experiment was to investigate the influence of low dose bovine colostrum supplementation on exercise performance in cyclists over a 10 week period that included 5 days of high intensity training (HIT). METHODS: Over 7 days of preliminary testing, 29 highly trained male road cyclists completed a VO(2max) test (in which their ventilatory threshold was estimated), a time to fatigue test at 110% of ventilatory threshold, and a 40 km time trial (TT40). Cyclists were then assigned to either a supplement (n = 14, 10 g/day bovine colostrum protein concentrate (CPC)) or a placebo group (n = 15, 10 g/day whey protein) and resumed their normal training. Following 5 weeks of supplementation, the cyclists returned to the laboratory to complete a second series of performance testing (week 7). They then underwent five consecutive days of HIT (week 8) followed by a further series of performance tests (week 9). RESULTS: The influence of bovine CPC on TT40 performance during normal training was unclear (week 7: 1+/-3.1%, week 9: 0.1+/-2.1%; mean+/-90% confidence limits). However, at the end of the HIT period, bovine CPC supplementation, compared to the placebo, elicited a 1.9+/-2.2% improvement from baseline in TT40 performance and a 2.3+/-6.0% increase in time trial intensity (% VO(2max)), and maintained TT40 heart rate (2.5+/-3.7%). In addition, bovine CPC supplementation prevented a decrease in ventilatory threshold following the HIT period (4.6+/-4.6%). CONCLUSION: Low dose bovine CPC supplementation elicited improvements in TT40 performance during an HIT period and maintained ventilatory threshold following five consecutive days of HIT.


Asunto(s)
Ciclismo/fisiología , Calostro , Suplementos Dietéticos , Adulto , Animales , Bovinos , Método Doble Ciego , Prueba de Esfuerzo/métodos , Humanos , Masculino , Consumo de Oxígeno/fisiología , Educación y Entrenamiento Físico , Resistencia Física/fisiología
20.
Transplant Proc ; 37(10): 4543-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16387165

RESUMEN

There is interest in the postulate that cyclosporine a (CsA) contributes to the elevated homocysteine levels seen in organ transplant recipients, as hyperhomocysteinemia is now considered an independent risk factor for cardiovascular disease (CVD) and may partially explain the increased prevalence of CVD in this population. The main purpose of this investigation was to determine the effect of CsA administration on plasma homocysteine. Eighteen female Sprague Dawley rats (4 months old) were randomly assigned to either a treatment or a control group. For 18 days the treatment group received of CsA (25 mg/kg/d) while the control group received the same volume of the vehicle. Blood samples obtained following sacrifice to measure CsA, total homocysteine, and plasma creatinine. There were no significant differences in plasma homocysteine (mean values +/- SD: treatment = 4.79 +/- 0.63 micromol/L, control = 4.46 +/- 0.75 micromol/L; P = .37). Homocysteine was not significantly correlated with final CsA concentrations (r = .17; P = .69). There was a significant difference in plasma creatinine values between the two groups (treatment = 60.44 +/- 7.68 micromol/L, control = 46.33 +/- 1.66 micromol/L; P < .001). Furthermore, plasma homocysteine and creatinine were positively correlated with the treatment group (r = .73; P < .05) but not the controls (r = -.10; P = .81). In conclusion, CsA does not influence plasma homocysteine concentrations in rats.


Asunto(s)
Ciclosporina/farmacología , Homocisteína/sangre , Animales , Creatinina/sangre , Ciclosporina/sangre , Femenino , Ratas , Ratas Sprague-Dawley
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