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1.
Metab Syndr Relat Disord ; 21(9): 517-525, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37672611

RESUMEN

Blood pressure (BP) responses to recommended aerobic training can vary widely between individuals. Although studies demonstrate the role of exercise training in regulating BP responsiveness, predictive models are still unknown. This study aimed to identify hemodynamic predictive markers for the diagnosis of BP responsiveness based on baseline characteristics and postexercise ambulatory blood pressure (ABP) before an aerobic training program in postmenopausal women. Sixty-five postmenopausal women with essential hypertension were randomly allocated into the continuous aerobic training (CAT, n = 51) and nonexercising control (CON, n = 14) groups. CAT group cycled at moderate intensity three times a week for 12 weeks. Individuals who failed to decrease systolic blood pressure (SBP) were classified as nonresponders (NRs; n = 34) based on typical error of measurement. Baseline anthropometric, metabolic, cardiovascular, hemodynamic variables, and postexercise ABP was measured to predict BP responsiveness. A logistic regression model based on Baseline SBP [odds ratio (OR) = 1.202; 95% confidence interval (CI) = 1.080-1.338], SBP Nighttime (OR = 0.889; 95% CI = 0.811-0.975), and heart rate (HR) Nighttime (OR = 1.127; 95% CI = 1.014-1.254) were able to diagnose responders and NR individuals to BP reduction in response to CAT with 92.6% accuracy (P < 0.001; Sensitivity = 94.1%; Specificity = 79.4%). The findings highlight the potential value of baseline clinical characteristics as Baseline SBP, SBP, and HR Nighttime as markers for diagnosing BP responsiveness to recommended CAT in hypertension postmenopausal women. Clinical Trial Registration number: RBR-3xnqxs8.


Asunto(s)
Sistema Cardiovascular , Hipertensión , Femenino , Humanos , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial , Posmenopausia , Hipertensión/diagnóstico , Hipertensión/terapia
2.
J Telemed Telecare ; : 1357633X221137626, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36469017

RESUMEN

INTRODUCTION: The aim was to identify whether cardiovascular telerehabilitation programs (CV-T-REHAB) can improve functional capacity, cardiorespiratory fitness and quality of life (QoL) to the same extent of presential rehabilitation (CV-P-REHAB) in older adults, by meta-analysis of previous studies. METHODS: Literature search was conducted in October 2020 in four databases to select controlled trials of CV-T-REHAB effects on functional capacity (six-minute walk test [6MWT]), cardiorespiratory fitness (maximal oxygen consumption [V˙O2max]), and QoL in older adults (> 50 years) and included new articles in April 2022. RESULTS: CV-T-REHAB improved 6MWT (11.14 m [CI95% = 8.03; 14.26], p < 0.001), V˙O2max (1.18 ml/kg/min [CI95% = 0.70; 1.66], p < 0.001), and QoL (standardized mean difference [SMD] = 0.36 [CI95% = 0.05; 0.67], p = 0.02). CV-T-REHAB increased V˙O2max to a greater extent than CV-P-REHAB (1.08 ml/kg/min [0.39; 1.76], p = 0.002). Although the 6MWT and V˙O2max analyses proved consistent and homogeneous, the QoL analysis showed considerable inconsistency (I2 = 92.90%), suggesting the need for studies exploring the effect of CV-T-REHAB on QoL in this population. Part of the heterogeneity was explained by age differences, as CV-T-REHAB improved QoL in adults >65 years, but not in adults <64 years. CONCLUSION: CV-T-REHAB improved cardiorespiratory fitness to a level equal to or higher than CV-P-REHAB and improved functional capacity and QoL; being mainly effective for QoL in older adults >65 years. Thus, CV-T-REHAB can be a good alternative, when not the best option and might be considered especially for individuals with limited access to participate in face-to-face programs.

3.
Metabolites ; 12(11)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36355124

RESUMEN

Increases in longevity and obesity have led to a higher prevalence of Metabolic Syndrome (MetS) and several chronic conditions, such as hypertension. The prevalence of MetS and hypertension increases with advancing age and their detrimental effects on health can be attenuated by physical activity. Combined aerobic and resistance exercise training (CT) is recommended to maintain good health in older adults and is known to generate important metabolic adaptations. In this study we performed a metabolomics analysis, based on Hydrogen Nuclear Magnetic Resonance (1H NMR), to investigate the kinetics of changes in metabolism in non-physically active older women with MetS in response to 16 weeks of CT. A subset of women with MetS were selected from a larger randomized trial (that included men and women without MetS), with 12 participants on CT and 13 from the Control Group (CG). CT comprised walking/running at 63% of VO2max, three times/week, and resistance training (RT), consisting of 15 repetitions of seven exercises at moderate intensity, twice/week. Serum metabolomic profile was analysed at baseline (0W), 4 (4W), 8 (8W), 12 (12W) and 16 weeks (16W) for CT or CG. Cardiorespiratory fitness, RT load, blood pressure, body composition, lipid and glycaemic profile were also assessed. After 16 weeks CT increased cardiorespiratory fitness (13.1%, p < 0.05) and RT load (from 48% in the lat pulldown to 160% in the leg press, p < 0.05), but there were no changes in MetS parameters, such as body composition (Body Mass, Body Mass Index (BMI), body fat percentage and waist circumference), blood pressure, lipid and glycaemic profile. However, we identified potential higher substrate to the tricarboxylic acid cycle (increase in 2-Oxobutyrate from 0W (0.0029 ± 0.0009) to 4W (0.0038 ± 0.0011) and 8W (0.0041 ± 0.0015), p < 0.05), followed by alterations (different from 0W, p < 0.05) in the production of ketone bodies (3-Hydroxybutyrate, 0W (0.0717 ± 0.0377) to 16W (0.0397 ± 0.0331), and Acetoacetate, 0W (0.0441 ± 0.0240) to 16W (0.0239 ± 0.0141)), which together might explain the known improvement in fatty acid oxidation with exercise. There was also a late increase in ornithine at 16W of CT. Further studies are needed to investigate the association between these metabolic pathways and clinical outcomes in this population.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36078774

RESUMEN

The aim was to identify whether 16 weeks of combined training (Training) reduces blood pressure of hypertensive older adults and what the key fitness, hemodynamic, autonomic, inflammatory, oxidative, glucose and/or lipid mediators of this intervention would be. Fifty-two individuals were randomized to either 16 weeks of Training or control group who remained physically inactive (Control). Training included walking/running at 63% of V˙O2max, three times per week, and strength training, consisting of one set of fifteen repetitions (seven exercises) at moderate intensity, twice per week. Both groups underwent a comprehensive health assessment at baseline (W0) and every four weeks, for 16 weeks total. p-value ≤ 0.05 was set as significant. Training did not reduce blood pressure. It increased V˙O2max after eight weeks and again after 16 weeks (~18%), differently from the Control group. At 16 weeks, Training increased strength (~8%), slightly reduced body mass (~1%), and reduced the number of individuals with metabolic syndrome (~7%). No other changes were observed (heart rate, carotid compliance, body composition, glycemic and lipid profile, inflammatory markers and oxidative profile, vasoactive substances, heart rate variability indices). Although Training increased cardiorespiratory fitness and strength, Training was able to reduce neither blood pressure nor a wide range of mediators in hypertensive older adults, suggesting other exercise interventions might be necessary to improve overall health in this population. The novelty of this study was the time-course characterization of Training effects, surprisingly demonstrating stability among a comprehensive number of health outcomes in hypertensive older adults, including blood pressure.


Asunto(s)
Capacidad Cardiovascular , Hipertensión , Entrenamiento de Fuerza , Anciano , Capacidad Cardiovascular/fisiología , Ejercicio Físico/fisiología , Humanos , Hipertensión/terapia , Lípidos
5.
Scand J Med Sci Sports ; 32(2): 402-413, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34706104

RESUMEN

The study aimed to identify and quantify the metabolites profile and metabolic pathways in human muscle tissue engaged during exhaustive high-intensity cycling exercise. Seven healthy physically active men performed a graded exercise test and an exhaustive supramaximal effort at 115% of maximal aerobic power with muscles biopsies performed in rest and immediately after exhaustion for quantifying of muscle metabolites changes by 1 H-NMR spectroscopy. The time until exhaustion (tlim) recorded was 224.7 ± 35.5 s whereas the muscle pH at exhaustion was 6.48 ± 0.05. A total of 54 metabolites were identified and quantified. The most enriched and impacted pathways included: beta oxidation of very long chain fatty acids, mitochondrial electron transport chain, alanine aspartate, and glutamate metabolism, citric acid cycle, arginine biosynthesis, propanoate metabolism, threonine and 2-oxobutanoate degradation and pyruvate metabolism. In addition, the muscle concentrations in Post exercise, compared to Pre increased significantly (p < 0.0398) for fumarate (42.0%), succinate (101.2%), glucose (249.7%), lactate (122.8%), O-acetylcarnitine (164.7%), glycerol (79.3%), AMP (288.2%), 2-oxobutyrate (121.0%), and methanol (58.5%), whereas decreased significantly (p < 0.010) for creatine phosphate (-70.2%), ADP (-56.5%), carnitine (-33.5%), and glutamate (-42.3%). Only the succinate was significantly correlated with tlim (r = -0.76; p = 0.0497). Besides the classical expected contribution of glycolytic and phosphagen energetic pathways, it was demonstrated that the high-intensity exercise is also associated with pathways indicatives of amino acid and fatty acid oxidation metabolisms, highlighting the inverse relation between changes in the intramuscular succinate levels and tlim.


Asunto(s)
Ejercicio Físico , Músculo Esquelético , Ciclismo , Prueba de Esfuerzo , Humanos , Masculino , Metabolómica
6.
Biomed Res Int ; 2021: 9415253, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34621899

RESUMEN

The present study was designed to compare the body composition and indicators of chronic inflammatory grade, such as leptin, adiponectin, and resistin concentrations in irregularly active and active SCI subjects. Thirty-two male subjects participated in this study. They were divided into three groups: able-bodied control irregularly active (control, n = 11), irregularly active with SCI (SCI-IA, n = 8), and physically active with SCI (SCI-PA, n = 13). The enzyme-linked immunosorbent assay (ELISA) assessed serum concentrations of leptin, adiponectin, and resistin. All volunteers performed the maximum oxygen uptake (VO2max) test, 24 h total energy expenditure (TEE), and body composition by skinfold thicknesses. Leptin concentrations were higher in the SCI-IA group when compared to the other groups, while no significant differences were found between the SCI-PA and control cohorts. In addition, no significant differences were found among groups for serum adiponectin and resistin concentrations either. The SCI-PA group showed significantly higher values for TEE and VO2max when compared to the other groups. Percentages of body fat and circumference were decreased in the control and SCI-PA groups when compared to the SCI-IA cohort. Associations between leptin and cardiorespiratory capacity and anthropometric markers were also observed. Our findings highlight that the lack of physical activity in the SCI subjects leads to poor general physical fitness and higher levels of body adiposity, which may induce hyperleptinemia, an essential marker for cardiometabolic disorders.


Asunto(s)
Ejercicio Físico , Leptina/sangre , Traumatismos de la Médula Espinal/sangre , Adulto , Humanos , Modelos Lineales
7.
Am J Physiol Cell Physiol ; 319(3): C541-C551, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32697599

RESUMEN

Lin28a/miRNA let-7b-5p pathway has emerged as a key regulators of energy homeostasis in the skeletal muscle. However, the mechanism through which this pathway is regulated in the skeletal muscle has remained unclear. We have found that 8 wk of aerobic training (Tr) markedly decreased let-7b-5p expression in murine skeletal muscle, whereas high-fat diet (Hfd) increased its expression. Conversely, Lin28a expression, a well-known inhibitor of let-7b-5p, was induced by Tr and decreased by Hfd. Similarly, in human muscle biopsies, Tr increased LIN28 expression and decreased let-7b-5p expression. Bioinformatics analysis of LIN28a DNA sequence revealed that its enrichment in peroxisome proliferator-activated receptor delta (PPARδ) binding sites, which is a well-known metabolic regulator of exercise. Treatment of primary mouse skeletal muscle cells or C2C12 cells with PPARδ activators GW501516 and AICAR increased Lin28a expression. Lin28a and let-7b-5p expression was also regulated by PPARδ coregulators. While PPARγ coactivator-1α (PGC1α) increased Lin28a expression, corepressor NCoR1 decreased its expression. Furthermore, PGC1α markedly reduced the let-7b-5p expression. PGC1α-mediated induction of Lin28a expression was blocked by the PPARδ inhibitor GSK0660. In agreement, Lin28a expression was downregulated in PPARδ knocked-down cells leading to increased let-7b-5p expression. Finally, we show that modulation of the Lin28a-let-7b-5p pathway in muscle cells leads to changes in mitochondrial metabolism in PGC1α dependent fashion. In summary, we demonstrate that Lin28a-let-7b-5p is a direct target of PPARδ in the skeletal muscle, where it impacts mitochondrial respiration.


Asunto(s)
Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , PPAR delta/metabolismo , Proteínas de Unión al ARN/genética , Animales , Línea Celular , Regulación hacia Abajo , Ratones , Fibras Musculares Esqueléticas/metabolismo , PPAR delta/genética
8.
Appl Physiol Nutr Metab ; 44(2): 216-220, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30001503

RESUMEN

We aimed to investigate the mechanisms underlying muscle growth after 12 weeks of resistance training performed with blood flow restriction (RT-BFR) and high-intensity resistance training (HRT) in older individuals. Participants were allocated into the following groups: HRT, RT-BFR, or a control group. High-throughput transcriptome sequencing was performed by the Illumina HiSeq 2500 platform. HRT and RT-BFR presented similar increases in the quadriceps femoris cross-sectional area, and few genes were differently expressed between interventions. The small differences in gene expression between interventions suggest that similar mechanisms may underpin training-induced muscle growth.


Asunto(s)
Envejecimiento/fisiología , Músculo Esquelético/metabolismo , Educación y Entrenamiento Físico , Flujo Sanguíneo Regional/fisiología , Entrenamiento de Fuerza , Transcriptoma/fisiología , Anciano , ADN/biosíntesis , ADN/genética , Dieta , Femenino , Regulación de la Expresión Génica/fisiología , Humanos , Pierna/anatomía & histología , Pierna/fisiología , Masculino , Persona de Mediana Edad , Músculo Esquelético/irrigación sanguínea , Músculo Cuádriceps/fisiología , ARN/biosíntesis , ARN/genética
9.
PLoS One ; 13(3): e0194776, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29596452

RESUMEN

PURPOSE: We investigated the energy system contributions and total energy expenditure during low intensity endurance exercise associated with blood flow restriction (LIE-BFR) and without blood flow restriction (LIE). METHODS: Twelve males participated in a contra-balanced, cross-over design in which subjects completed a bout of low-intensity endurance exercise (30min cycling at 40% of [Formula: see text]) with or without BFR, separated by at least 72 hours of recovery. Blood lactate accumulation and oxygen uptake during and after exercise were used to estimate the anaerobic lactic metabolism, aerobic metabolism, and anaerobic alactic metabolism contributions, respectively. RESULTS: There were significant increases in the anaerobic lactic metabolism (P = 0.008), aerobic metabolism (P = 0.020), and total energy expenditure (P = 0.008) in the LIE-BFR. No significant differences between conditions for the anaerobic alactic metabolism were found (P = 0.582). Plasma lactate concentration was significantly higher in the LIE-BFR at 15min and peak post-exercise (all P≤0.008). Heart rate was significantly higher in the LIE-BFR at 10, 15, 20, 25, and 30min during exercise, and 5, 10, and 15min after exercise (all P≤0.03). Ventilation was significantly higher in the LIE-BFR at 10, 15, and 20min during exercise (all P≤0.003). CONCLUSION: Low-intensity endurance exercise performed with blood flow restriction increases the anaerobic lactic and aerobic metabolisms, total energy expenditure, and cardiorespiratory responses.


Asunto(s)
Circulación Sanguínea , Ejercicio Físico , Ácido Láctico/metabolismo , Consumo de Oxígeno , Adolescente , Adulto , Anaerobiosis , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Adulto Joven
10.
Nutrients ; 10(4)2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29596307

RESUMEN

It remains unclear as to what extent resistance training (RT) can attenuate muscle loss during caloric restriction (CR) interventions in humans. The objective here is to address if RT could attenuate muscle loss induced by CR in obese elderly individuals, through summarized effects of previous studies. Databases MEDLINE, Embase and Web of Science were used to perform a systematic search between July and August 2017. Were included in the review randomized clinical trials (RCT) comparing the effects of CR with (CRRT) or without RT on lean body mass (LBM), fat body mass (FBM), and total body mass (BM), measured by dual-energy X-ray absorptiometry, on obese elderly individuals. The six RCTs included in the review applied RT three times per week, for 12 to 24 weeks, and most CR interventions followed diets of 55% carbohydrate, 15% protein, and 30% fat. RT reduced 93.5% of CR-induced LBM loss (0.819 kg [0.364 to 1.273]), with similar reduction in FBM and BM, compared with CR. Furthermore, to address muscle quality, the change in strength/LBM ratio tended to be different (p = 0.07) following CRRT (20.9 ± 23.1%) and CR interventions (−7.5 ± 9.9%). Our conclusion is that CRRT is able to prevent almost 100% of CR-induced muscle loss, while resulting in FBM and BM reductions that do not significantly differ from CR.


Asunto(s)
Restricción Calórica , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Anciano , Humanos
11.
Appl Physiol Nutr Metab ; 43(3): 240-246, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29049889

RESUMEN

The present study aimed to compare the early metabolic response between high-load resistance exercise (HL-RE) and low-load resistance exercise with blood flow restriction (LL-BFR). Nine young, well-trained men participated in a randomized crossover design in which each subject completed LL-BFR, HL-RE, or condition control (no exercise) with a 1-week interval between them. Blood samples were taken immediately before and 5 min after the exercise sessions. Nuclear magnetic resonance spectroscopy identified and quantified 48 metabolites, 6 of which presented significant changes among the exercise protocols. The HL-RE promoted a higher increase in pyruvate, lactate, and alanine compared with the LL-BFR and the control. HL-RE and LL-BFR promoted a higher increase in succinate compared with the control; however, there was no difference between HL-RE and LL-BFR. Also, while there was no difference in acetoacetate between HL-RE and LL-BFR, a greater decrease was observed in both compared with the control. Finally, LL-BFR promoted a greater decrease in choline compared with the control. In conclusion, this study provides by metabolomics a new insight in metabolic response between LL-BFR and HL-RE by demonstrating a distinct response to some metabolites that are not commonly analyzed.


Asunto(s)
Metabolismo Energético/fisiología , Metabolómica , Entrenamiento de Fuerza , Adulto , Hemodinámica , Humanos , Masculino , Flujo Sanguíneo Regional/fisiología , Adulto Joven
12.
Motriz (Online) ; 24(4): e101866, 2018. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-976262

RESUMEN

This article is a methodological description of a randomized clinical trial (ClinicalTrials.gov U1111-1181-4455) aiming to evaluate the time-course (monthly) and associations between blood pressure changes and other health-related adaptations in response to exercise training in hypertensive elderly. Methods: The patients will be randomized to a control or combined training group interventions (aerobic and resistance exercise), with monthly assessments in four months. Although, the changes in baseline blood pressure is the primary clinical outcome, the secondary outcomes include: body composition, cardiorespiratory fitness, muscle strength, arterial stiffness, baroreceptor sensitivity, cardiovascular autonomic modulation, inflammatory markers, oxidative stress, growth factors, tissue remodeling markers, metabolic profile, renal function, cognitive function and quality of life. Results: To support the understanding of the blood pressure changes in hypertensive elderly, a time-course of exercise-induced adaptations including cardiovascular and immunological adaptations are fundamental for research in this field. Conclusion: To investigate the time-course of combined training-induced adaptations including all the diverse aspects of health in hypertensive elderly a well-controlled protocol design is necessary, mainly to clarify the relationship between cardiovascular and immunological exercise-induced adaptations.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Anciano , Ejercicio Físico/fisiología , Hipertensión/fisiopatología , Calidad de Vida , Envejecimiento/inmunología , Entrenamiento de Fuerza/efectos adversos
13.
J Sports Sci ; 35(12): 1211-1218, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27686013

RESUMEN

This study analysed the time course of the global metabolic acute response after resistance exercise (RE), with the use of proton nuclear magnetic resonance (1H NMR) spectroscopy. Ten young healthy males performed 4 sets of 10 repetitions at 70% of one-repetition maximum in the leg press and knee extension exercises and had the serum metabolome assessed at 5, 15, 30 and 60 min post-RE. Measurements were also performed 1 h earlier and immediately before the exercises, as an attempt to characterise each participant's serum metabolome at rest. One-way ANOVA was applied and the significance level was set at P ≤ 0.05. RE promoted an increase in 2-hydroxybutyrate, 2-oxoisocaproate, 3-hydroxyisobutyrate, alanine, hypoxanthine, lactate, pyruvate and succinate concentrations. However, isoleucine, leucine, lysine, ornithine and valine had their concentrations decreased post-RE compared with at rest. This is the first study to show significant changes in serum concentration of metabolites such as 2-oxoisocaproate, 2-hydroxybutyrate, 3-hydroxyisobutyrate, lysine, hypoxanthine and pyruvate post-RE, attesting metabolomics as an interesting approach to advance in the understanding of global RE-induced metabolic changes. Moreover, the present data could influence the time point of blood collection in the future studies that aims to investigate metabolism and exercise.


Asunto(s)
Metaboloma/fisiología , Entrenamiento de Fuerza , Metabolismo Energético/fisiología , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Fuerza Muscular/fisiología , Factores de Tiempo , Adulto Joven
14.
Med Sci Sports Exerc ; 47(10): 2207-15, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26378946

RESUMEN

PURPOSE: We investigated the effects of 24 wk of combined training on proinflammatory and anti-inflammatory markers associated with obesity in obese middle-age men. METHODS: Thirty obese men (48.73 ± 1.04 yr; body mass index, 31.00 ± 0.29 kg·m) underwent 24 wk of combined training [CT (N = 17), aerobic (50%-85% of V˙O2peak) and resistance (6-10 maximum repetition [RM]) training)] three times per week, 60 min per session, or a control group (N = 13). Anthropometric measures, maximal strength for leg press and bench press, peak oxygen uptake (V˙O2peak) and serum concentrations of C-reactive protein (CRP), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), IL-10, IL-15, resistin, leptin, and adiponectin were determined before (M1) and after 8 (M2), 16 (M3), and 24 (M4) wk of the experimental design. RESULTS: Significant increases were observed in the maximal strength for bench press and leg press, V˙O2peak, and serum concentrations of adiponectin and IL-15 for CT. Concomitantly, significant decreases were observed in percentage body fat and serum concentrations of CRP, resistin, and leptin for CT after the experimental period. CONCLUSION: Twenty-four weeks of moderate- to high-intensity CT reduced markers of subclinical inflammation associated with obesity and improved insulin resistance and functional capabilities of obese middle-age men, regardless of dietary intervention and weight loss.


Asunto(s)
Terapia por Ejercicio/métodos , Inflamación/prevención & control , Obesidad/patología , Obesidad/terapia , Adiponectina/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Distribución de la Grasa Corporal , Proteína C-Reactiva/metabolismo , Humanos , Resistencia a la Insulina , Interleucina-15/sangre , Pierna/fisiología , Leptina/sangre , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Obesidad/fisiopatología , Consumo de Oxígeno , Aptitud Física , Entrenamiento de Fuerza , Resistina/sangre , Factor de Necrosis Tumoral alfa/sangre
15.
J Strength Cond Res ; 29(4): 1071-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25264670

RESUMEN

High-intensity resistance training (HRT) has been recommended to offset age-related loss in muscle strength and mass. However, part of the elderly population is often unable to exercise at high intensities. Alternatively, low-intensity resistance training with blood flow restriction (LRT-BFR) has emerged. The purpose of this study was to compare the effects of LRT-BFR and HRT on quadriceps muscle strength and mass in elderly. Twenty-three elderly individuals, 14 men and 9 women (age, 64.04 ± 3.81 years; weight, 72.55 ± 16.52 kg; height, 163 ± 11 cm), undertook 12 weeks of training. Subjects were ranked according to their pretraining quadriceps cross-sectional area (CSA) values and then randomly allocated into one of the following groups: (a) control group, (b) HRT: 4 × 10 repetitions, 70-80% one repetition maximum (1RM), and (c) LRT-BFR: 4 sets (1 × 30 and 3 × 15 repetitions), 20-30% 1RM. The occlusion pressure was set at 50% of maximum tibial arterial pressure and sustained during the whole training session. Leg press 1RM and quadriceps CSA were evaluated at before and after training. A mixed-model analysis was performed, and the significance level was set at p ≤ 0.05. Both training regimes were effective in increasing pre- to post-training leg press 1RM (HRT: ∼54%, p < 0.001; LRT-BFR: ∼17%, p = 0.067) and quadriceps CSA (HRT: 7.9%, p < 0.001; LRT-BFR: 6.6%, p < 0.001); however, HRT seems to induce greater strength gains. In summary, LRT-BFR constitutes an important surrogate approach to HRT as an effective training method to induce gains in muscle strength and mass in elderly.


Asunto(s)
Fuerza Muscular , Acondicionamiento Físico Humano/métodos , Acondicionamiento Físico Humano/fisiología , Músculo Cuádriceps/irrigación sanguínea , Músculo Cuádriceps/fisiología , Entrenamiento de Fuerza/métodos , Anciano , Presión Arterial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Cuádriceps/anatomía & histología , Flujo Sanguíneo Regional/fisiología , Arterias Tibiales/fisiología
16.
Clin Physiol Funct Imaging ; 35(4): 245-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24797398

RESUMEN

The aim of this study was to investigate the effects of the ageing process in the electromechanical delay (EMD), rate of torque development (RTD) and peak torque (PT) of the knee extensor muscles. The volunteers were assigned to three groups: young group (YG - 23·44 ± 4·74 years, 78·14 ± 15·11 kg, 1·72 ± 0·05 m), middle-aged group (MAG - 49·56 ± 6·06 years, 72·01 ± 14·07 kg, 1·67 ± 0·06 m) and elderly group (EG - 68·67 ± 9·06 years, 67·96 ± 7·60 kg, 1·64 ± 0·07 m). The PT and RTD were assessed during maximal voluntary ballistic isometric contractions (MVBIC) in the isokinetic dynamometer. Muscle electrical activity was recorded (EMG) during MVBIC in the vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) muscles. The EMD was calculated during the MVBIC, through the time interval between the EMG onset and torque onset. The PT and RTD were higher in the YG than in the MAG (P = 0·02; P = 0·01, respectively) and in the EG (P = 0·002; P = 0·0004, respectively). There were no significant differences in EMD among the three age groups for the VL, VM and RF (P>0·05) muscles. We conclude that age affects the PT and RTD, but not EMD of the VL, VM and RF muscles.


Asunto(s)
Envejecimiento/fisiología , Acoplamiento Excitación-Contracción/fisiología , Contracción Isométrica/fisiología , Articulación de la Rodilla/fisiología , Músculo Esquelético/fisiología , Resistencia Física/fisiología , Adulto , Anciano , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Torque , Adulto Joven
17.
Clin Physiol Funct Imaging ; 33(6): 450-4, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23701469

RESUMEN

The aim of this study was to compare the acute hormonal responses following two different eccentric exercise velocities. Seventeen healthy, untrained, young women were randomly placed into two groups to perform five sets of six maximal isokinetic eccentric actions at slow (30° s(-1) ) and fast (210° s(-1) ) velocities with 60-s rest between sets. Growth hormone, cortisol, free and total testosterone were assessed by blood samples collected at baseline, immediately postexercise, 5, 15 and 30 min following eccentric exercise. Changes in hormonal responses over time were compared between groups, using a mixed model followed by a Tukey's post hoc test. The main findings of the present study were that the slow group showed higher growth hormone values immediately (5·08 ± 2·85 ng ml(-1) , P = 0·011), 5 (5·54 ± 3·01 ng ml(-1) , P = 0·004) and 15 min (4·30 ± 2·87 ng ml(-1) , P = 0·021) posteccentric exercise compared with the fast group (1·39 ± 2·41 ng ml(-1) , 1·34 ± 1·97 ng ml(-1) and 1·24 ± 1·87 ng ml(-1) , respectively), and other hormonal responses were not different between groups (P>0·05). In conclusion, slow eccentric exercise velocity enhances more the growth hormone(GH) response than fast eccentric exercise velocity without cortisol and testosterone increases.


Asunto(s)
Ejercicio Físico , Hormona de Crecimiento Humana/sangre , Hidrocortisona/sangre , Contracción Muscular , Músculo Esquelético/fisiología , Testosterona/sangre , Adulto , Biomarcadores/sangre , Brasil , Femenino , Humanos , Factores de Tiempo , Adulto Joven
18.
Artículo en Portugués | LILACS | ID: lil-609279

RESUMEN

O presente estudo teve como objetivo investigar o efeito de 12 semanas de treinamento com pesos (TP) na flexibilidade de homens de meia-idade. Possivelmente, indivíduos na meia-idade sedentários apresentem melhoras na flexibilidade somente com a realização de TP. Foram selecionados 16 indivíduos de meia-idade (48,8 ± 5,0 anos) divididos aleatoriamente em dois grupos: grupo controle (GC, n=8) e grupo treinamento (GT, n=8). O GT realizou TP duas vezes por semana, em dias não consecutivos (3 séries de 15 repetições, 1 minuto de pausa). A flexibilidade de ombro, tronco, quadril e joelhos foram aferidas bilateralmente (com exceção do tronco) antes e após o período experimental. Não foi verificado efeito do tempo para nenhuma das variáveis analisadas (p>0,05). O TP de baixa intensidade não reduz a flexibilidade de homens de meia-idade.


The aim of the present study was to investigate the effect of 12 weeks of resistance training on flexibility levels of middle-aged men. Possibly, middle-aged sedentary subjects might show flexibility improvements only performing resistance training. Sixteen middle-aged men (48.8 ± 5.0 years) were selected for the present study. They were randomly divided in two groups: control group (GC, n=8) and training group (GT, n=8). The GT performed resistance training twice a week, in alternate days (3 sets of 15 repetitions, with 1 minute rest between sets). Shoulder, trunk, hips and knees flexibility were assessed bilaterally (with the exception of trunk) pre- and post- study period. No significant time interaction was found for any variable (p>0.05). Low-intensity resistance training does not reduce middle-aged men flexibility.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Envejecimiento/fisiología , Ejercicios de Estiramiento Muscular
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