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1.
J. physiol. biochem ; 80(1): 161-173, Feb. 2024. graf
Artigo em Inglês | IBECS | ID: ibc-EMG-574

RESUMO

Resistance training (RT) can increase the heat shock response (HSR) in the elderly. As middle-aged subjects already suffer physiological declines related to aging, it is hypothesized that RT may increase the HSR in these people. To assess the effects of resistance training on heat shock response, intra and extracellular HSP70, oxidative stress, inflammation, body composition, and metabolism in middle-aged subjects. Sixteen volunteers (40 – 59 years) were allocated to two groups: the trained group (n = 7), which performed 12 weeks of RT; and the physically inactive—control group (n = 9), which did not perform any type of exercise. The RT program consisted of 9 whole-body exercises (using standard gym equipment) and functional exercises, carried out 3 times/week. Before and after the intervention, body composition, muscle mass, strength, functional capacity, and blood sample measurements (lipid profile, glucose, insulin, oxidative damage, TNF-α, the HSR, HSP70 expression in leukocytes, and HSP72 in plasma) were performed. The HSR analysis demonstrated that this response is maintained at normal levels in middle-aged people and that RT did not cause any improvement. Also, RT increases muscle mass, strength, and functional capacity. Despite no additional changes of RT on the antioxidant defenses (catalase, glutathione peroxidase, and reductase) or inflammation, lipid peroxidation was diminished by RT (group x time interaction, p = 0.009), indicating that other antioxidant defenses may be improved after RT. HSR is preserved in middle-aged subjects without metabolic complications. In addition, RT reduces lipid peroxidation and can retard muscle mass and strength loss related to the aging process. (AU)


Assuntos
Humanos , Pessoa de Meia-Idade , Resposta ao Choque Térmico , Treinamento de Força , Proteínas de Choque Térmico HSP70 , Estresse Oxidativo , Inflamação , Metabolismo
2.
J. physiol. biochem ; 80(1): 161-173, Feb. 2024. graf
Artigo em Inglês | IBECS | ID: ibc-229948

RESUMO

Resistance training (RT) can increase the heat shock response (HSR) in the elderly. As middle-aged subjects already suffer physiological declines related to aging, it is hypothesized that RT may increase the HSR in these people. To assess the effects of resistance training on heat shock response, intra and extracellular HSP70, oxidative stress, inflammation, body composition, and metabolism in middle-aged subjects. Sixteen volunteers (40 – 59 years) were allocated to two groups: the trained group (n = 7), which performed 12 weeks of RT; and the physically inactive—control group (n = 9), which did not perform any type of exercise. The RT program consisted of 9 whole-body exercises (using standard gym equipment) and functional exercises, carried out 3 times/week. Before and after the intervention, body composition, muscle mass, strength, functional capacity, and blood sample measurements (lipid profile, glucose, insulin, oxidative damage, TNF-α, the HSR, HSP70 expression in leukocytes, and HSP72 in plasma) were performed. The HSR analysis demonstrated that this response is maintained at normal levels in middle-aged people and that RT did not cause any improvement. Also, RT increases muscle mass, strength, and functional capacity. Despite no additional changes of RT on the antioxidant defenses (catalase, glutathione peroxidase, and reductase) or inflammation, lipid peroxidation was diminished by RT (group x time interaction, p = 0.009), indicating that other antioxidant defenses may be improved after RT. HSR is preserved in middle-aged subjects without metabolic complications. In addition, RT reduces lipid peroxidation and can retard muscle mass and strength loss related to the aging process. (AU)


Assuntos
Humanos , Pessoa de Meia-Idade , Resposta ao Choque Térmico , Treinamento de Força , Proteínas de Choque Térmico HSP70 , Estresse Oxidativo , Inflamação , Metabolismo
3.
J Physiol Biochem ; 80(1): 161-173, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930617

RESUMO

Resistance training (RT) can increase the heat shock response (HSR) in the elderly. As middle-aged subjects already suffer physiological declines related to aging, it is hypothesized that RT may increase the HSR in these people. To assess the effects of resistance training on heat shock response, intra and extracellular HSP70, oxidative stress, inflammation, body composition, and metabolism in middle-aged subjects. Sixteen volunteers (40 - 59 years) were allocated to two groups: the trained group (n = 7), which performed 12 weeks of RT; and the physically inactive-control group (n = 9), which did not perform any type of exercise. The RT program consisted of 9 whole-body exercises (using standard gym equipment) and functional exercises, carried out 3 times/week. Before and after the intervention, body composition, muscle mass, strength, functional capacity, and blood sample measurements (lipid profile, glucose, insulin, oxidative damage, TNF-α, the HSR, HSP70 expression in leukocytes, and HSP72 in plasma) were performed. The HSR analysis demonstrated that this response is maintained at normal levels in middle-aged people and that RT did not cause any improvement. Also, RT increases muscle mass, strength, and functional capacity. Despite no additional changes of RT on the antioxidant defenses (catalase, glutathione peroxidase, and reductase) or inflammation, lipid peroxidation was diminished by RT (group x time interaction, p = 0.009), indicating that other antioxidant defenses may be improved after RT. HSR is preserved in middle-aged subjects without metabolic complications. In addition, RT reduces lipid peroxidation and can retard muscle mass and strength loss related to the aging process.


Assuntos
Resposta ao Choque Térmico , Treinamento de Força , Idoso , Humanos , Pessoa de Meia-Idade , Antioxidantes , Resposta ao Choque Térmico/fisiologia , Inflamação/metabolismo , Estresse Oxidativo/fisiologia , Proteínas de Choque Térmico HSP70/metabolismo
4.
Cell Stress Chaperones ; 28(6): 721-729, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37462825

RESUMO

Being overweight is already considered a metabolic risk factor, which can be overcome by increasing cardiorespiratory fitness (CRF). Acute exercise is known to induce changes in plasma hormones and heat shock proteins release. However, there is a lack of studies investigating the impact of body composition and CRF on these variables following acute aerobic exercise. To assess the influence of body composition and cardiorespiratory fitness on plasma heat shock protein 72 kDa (HSP72), norepinephrine (NE), insulin, and glucose responses to an acute aerobic exercise bout in the fed state. Twenty-four healthy male adults were recruited and allocated into three groups: overweight sedentary (n = 8), normal weight sedentary (n = 8), and normal weight active (n = 8). The volunteers performed an acute moderate exercise session on a treadmill at 70% of VO2 peak. Blood samples were drawn at baseline, immediately post-exercise, and at 1-h post-exercise. The exercise session did not induce changes in HSP72 nor NE but changes in glucose and insulin were affected by body mass index. Also, subjects with elevated CRF maintain reduced NE through exercise. At baseline, the overweight sedentary group showed elevated NE, insulin, and glucose; these last two impacting the HOMA-IR index. Thirty minutes of aerobic exercise at 70% VO2 peak, in the fed state, did not change the levels of plasma NE and HSP72. Elevated body composition seems to impact metabolic profile and increase sympathetic activity. Conversely, subjects with increased cardiorespiratory fitness seem to have attenuated sympathetic activity.


Assuntos
Aptidão Cardiorrespiratória , Insulina , Adulto , Humanos , Masculino , Sobrepeso , Glucose , Proteínas de Choque Térmico HSP72 , Aptidão Cardiorrespiratória/fisiologia , Norepinefrina , Exercício Físico/fisiologia , Composição Corporal
5.
J Bodyw Mov Ther ; 35: 164-168, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37330764

RESUMO

Body composition (i.e., fat and lean mass profile) has been related to aerobic performance, an essential capacity for futsal athletes. The present study aimed to verify the relationship between total and regional body composition (percentage of fat and lean mass) with aerobic performance in elite futsal players. Male professional futsal athletes (n = 44) from two Brazilian National Futsal League teams and athletes representing the National team participated in this study. Body composition was evaluated using DXA (Dual-Energy X-ray Absorptiometry) and aerobic fitness by ergospirometry. There was a negative (p < 0.05) correlation between maximum oxygen uptake and maximal velocity reached with total body (r = -0.53; r = -0.58), trunk (r = -0.52; r = -0.56) and lower-limb (r = -0.46; r = -0.55) fat mass percentage. Lower-limb lean mass percentage had a positive (p < 0.05) correlation with maximum oxygen uptake (r = 0.46) and maximal velocity (r = 0.55). In conclusion, total and regional body composition present a relationship with aerobic performance in professional futsal players.


Assuntos
Futebol Americano , Esportes , Humanos , Masculino , Consumo de Oxigênio , Oxigênio , Exercício Físico , Atletas , Composição Corporal
6.
Appl Physiol Nutr Metab ; 48(5): 386-392, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36800893

RESUMO

Different types of muscle contraction can cause different damage to the musculature and differences in inflammatory responses. Acute increases in circulatory inflammation markers can influence the crosstalk between coagulation and fibrinolysis processes, increasing the risk of thrombus formation and detrimental cardiovascular events. The aim of this study was to analyze the effects of concentric and eccentric exercise on hemostasis markers, C-reactive protein (CRP), and the relationship between these variables. Eleven healthy subjects with a mean age of 25.4 ± 2.8, non-smokers, with no history of cardiovascular disease and blood type O, randomly performed an isokinetic exercise protocol consisting of 75 concentric (CP) or eccentric (EP) contractions of knee extension, divided into five sets of 15 repetitions combined with 30-s rest. Blood samples for analysis of FVIII, von Willebrand factor, tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), and CRP were collected pre, post, 24 h, and 48 h after each protocol. Increased levels of CRP at 48 h in EP versus CP (p = 0.002), increased PAI-1 activity 48 h in EP versus CP (p = 0.044), and a reduction in t-PA at 48 h when compared with post-protocol in both protocols (p = 0.001). A correlation was found between CRP and PAI-1 at 48 h of PE (r2 = 0.69; p = 0.02). This study showed that both EP and CP increase the clotting process, albeit only the exercise performed eccentrically induces inhibition of fibrinolysis. This is possibly due to the increase in PAI-1 48 h after the protocol, which correlates with the increase in inflammation as demonstrated by the CRP levels.


Assuntos
Fibrinólise , Inibidor 1 de Ativador de Plasminogênio , Masculino , Humanos , Adulto Jovem , Adulto , Ativador de Plasminogênio Tecidual , Inflamação , Proteína C-Reativa
7.
Rev. bras. med. esporte ; 29: e2021_0398, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1387943

RESUMO

ABSTRACT Introduction: Childhood obesity is increasing and, as a consequence, it generates health complications resulting from sedentary behavior and low levels of physical fitness. There are few studies involving children, metabolic and cardiorespiratory profiles, and soccer. Objective: The purpose was to measure the effects of a 12-week recreational small-sided soccer program on cardiometabolic risk and individual responses to cardiometabolic risk factors in overweight or obese boys. Methods: Thirteen boys aged 8-12 years (34.9±11.6% body fat) participated in a 12-week recreational small-sided soccer training program with two 80-minute sessions per week at intensities over 80% of the maximal heart rate. Anthropometric characteristics, cardiorespiratory fitness, metabolic profile, individual responses to peak oxygen uptake (VO2peak), maximal workload (Wmax), fasting blood glucose, insulin, HOMA-IR, LDL-C, HDL-C, TC, and TG were measured both pre- and post-training. Results: Considering the individual responses of the participants, recreational soccer training was effective in improving variations in maximum power and exhaustion time, as well as promoting at least one beneficial change in cardiometabolic risk factors in 84% of the overweight or obese children. There were no differences between pre- and post-program anthropometric characteristics, metabolic profiles, or VO2peak values. Conclusion: Twelve-week recreational small-sided soccer programs were able to improve maximal power and anaerobic capacity and maintain cardiometabolic risk factor levels in overweight and obese boys. Level of evidence I; High-quality prospective study (all patients were enrolled at the same stage of disease, with >80% of patients enrolled) .


RESUMEN Introdução: La obesidad infantil está aumentando y, como consecuencia, genera complicaciones de salud derivadas del comportamiento sedentario y de los bajos niveles de aptitud física. Existen pocos estudios sobre niños, perfiles metabólicos, cardiorrespiratorios y fútbol. Objetivo: El objetivo fue medir los efectos de un programa de fútbol recreativo reducido de 12 semanas sobre el riesgo cardiometabólico y respuestas individuales en niños con sobrepeso u obesos. Métodos: Trece niños de 8 a 12 años (34,9 ± 11,6% de grasa corporal) participaron en un programa de entrenamiento de fútbol recreativo reducido de 12 semanas con dos sesiones de 80 minutos por semana a intensidades superiores al 80% de la frecuencia cardíaca máxima. Se midieron las características antropométricas, la aptitud cardiorrespiratoria, el perfil metabólico y las respuestas individuales del consumo máximo de oxígeno (VO2pico), la carga de trabajo máxima (Wmax), la glucemia y la insulina en ayunas, HOMA-IR, LDL-C, HDL-C, CT y TG antes y después del entrenamiento. Resultados: Teniendo en cuenta las respuestas individuales, el entrenamiento de fútbol recreativo fue eficaz para mejorar las variaciones de potencia máxima y el tiempo hasta el agotamiento, así como para promover al menos un cambio beneficioso en los factores de riesgo cardiometabólico en el 84% de los niños con sobrepeso u obesidad. No hubo diferencias entre las características antropométricas, los perfiles metabólicos o el pico de VO2 antes y después del programa. Conclusões: Doce semanas de programas de fútbol recreativo reducido fueron capaces de mejorar la potencia máxima y la capacidad anaeróbica, así como de mantener los niveles de factores de riesgo cardiometabólicos en niños con sobrepeso y obesidad. Nível de evidência I; Estudo prospectivo de alta qualidade (todos os pacientes foram inscritos no mesmo estágio da doença, com > 80% dos pacientes inscritos) .


RESUMO Introdução: A obesidade infantil está aumentando e, como consequência, gera complicações de saúde decorrentes do comportamento sedentário e baixos níveis de aptidão física. Existem poucos estudos que envolvem crianças, perfis metabólicos e cardiorrespiratórios e futebol. Objetivo: O objetivo foi medir os efeitos de um programa de futebol recreativo reduzido de 12 semanas sobre o risco cardiometabólico e respostas individuais em meninos com sobrepeso ou obesos. Métodos: Treze meninos de 8 a 12 anos (34,9 ± 11,6% de gordura corporal) participaram de um programa de treinamento de futebol recreativo reduzido de 12 semanas com duas sessões de 80 minutos por semana em intensidades acima de 80% da frequência cardíaca máxima. As características antropométricas, a aptidão cardiorrespiratória, o perfil metabólico e as respostas individuais do pico de consumo de oxigênio (VO2pico), carga máxima de trabalho (Wmáx), glicemia e insulina em jejum, HOMA-IR, LDL-C, HDL-C, CT e TG foram medidos pré e pós-treinamento. Resultados: considerando as respostas individuais dos participantes, o treinamento recreativo de futebol foi eficaz para melhorar as variações da potência máxima e do tempo até a exaustão, bem como promover pelo menos uma alteração benéfica nos fatores de risco cardiometabólico em 84% das crianças com sobrepeso ou obesidade. Não houve diferenças entre as características antropométricas pré e pós-programa, perfis metabólicos ou VO2pico. Conclusões: Doze semanas de programas de futebol recreativo reduzido foram capazes de melhorar a potência máxima e a capacidade anaeróbica, bem como manter os níveis de fatores de risco cardiometabólicos em meninos com sobrepeso e obesos. Nível de evidência I; Estudo prospectivo de alta qualidade (todos os pacientes foram inscritos no mesmo estágio da doença, com > 80% dos pacientes inscritos) .

8.
Front Physiol ; 13: 993258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311227

RESUMO

This study aimed to evaluate the acute effects of aerobic and resistance exercises on blood pressure and endothelial blood markers. We also correlated post-exercise blood pressure response with baseline cardiovascular parameters in middle-aged patients with hypertension. This cross-sectional study randomized 54 volunteers into the aerobic exercise group (AG, n = 27; 45.6 ± 7.7 years) or dynamic resistance exercise group (RG, n = 27; 45.8 ± 8.4 years). Blood marker evaluation, cardiopulmonary exercise tests, resting blood pressure monitoring, ambulatory blood pressure monitoring (ABPM), flow-mediated dilatation monitoring, and body composition evaluation were carried out. Exercise sessions were performed to evaluate post-exercise hypotension (PEH) and endothelial marker responses, in addition to post-exercise ABPM (ABPMex). This study is an arm of the study which was approved by the local ethics committee (No. 69373217.3.0000.5347) in accordance with the Helsinki Declaration and was registered at ClinicalTrials.gov (NCT03282942). The AG performed walking/running at 60% of the reserve heart rate, while the RG performed 10 exercises with two sets of 15-20 repetitions. The mean 24 h ABPM and ABPMex values showed no significant statistical differences. Systolic and diastolic blood pressure hypotension after aerobic and dynamic resistance were -10.59 ± 5.24/-6.15 ± 6.41 mmHg and -5.56 ± 7.61/-6.20 ± 8.25 mmHg, respectively. For an up-to-7 h assessment of resting pressure, there was a positive effect in the aerobic group. The concentrations of nitrites/nitrates (NOx) and endothelin-1 (ET-1) did not change during hypotension. Moreover, PEH and ABPMex were significantly correlated with baseline health variables. Thus, when middle-aged patients with hypertension perform aerobic or resistance exercise, the NOx/ET-1 pathway does not provide the best explanation for PEH. Finally, we found associations between baseline cardiovascular variables and endothelial vasoconstrictors with PEH.

9.
Physiol Rep ; 10(18): e15464, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36117383

RESUMO

Nucleotidases contribute to the regulation of inflammation, coagulation, and cardiovascular activity. Exercise promotes biological adaptations, but its effects on nucleotidase activities and expression are unclear. The objective of this study was to review systematically the effects of exercise on nucleotidase functionality in healthy and unhealthy subjects. The MEDLINE, EMBASE, Cochrane Library, and Web of Science databases were searched to identify, randomized clinical trials, non-randomized clinical trials, uncontrolled clinical trials, quasi-experimental, pre-, and post-interventional studies that evaluated the effects of exercise on nucleotidases in humans, and was not limited by language and date. Two independent reviewers performed the study selection, data extraction, and assessment of risk of bias. Of the 203 articles identified, 12 were included in this review. Eight studies reported that acute exercise, in healthy and unhealthy subjects, elevated the activities or expression of nucleotidases. Four studies evaluated the effects of chronic training on nucleotidase activities in the platelets and lymphocytes of patients with metabolic syndrome, chronic kidney disease, and hypertension and found a decrease in nucleotidase activities in these conditions. Acute and chronic exercise was able to modify the blood plasma and serum levels of nucleotides and nucleosides. Our results suggest that short- and long-term exercise modulate nucleotidase functionality. As such, purinergic signaling may represent a novel molecular adaptation in inflammatory, thrombotic, and vascular responses to exercise.


Assuntos
Exercício Físico , Hipertensão , Terapia por Exercício , Humanos , Nucleotidases , Nucleotídeos
10.
BMC Womens Health ; 22(1): 15, 2022 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-35034662

RESUMO

BACKGROUND: In the literature, professions that impose body standards for daily performance are designated as non-conventional professions (i.e. models, athletes, ballet dancers), with great emphasis on the female population. More than a job, it becomes a lifestyle to those inserted in this environment, thus, thousands of children and adolescents seek inclusion and success in these professions due to financial and media gains. Such professions are associated with several health-related risk factors. The purpose of this study was to identify and compare among physical fitness levels, cardiometabolic health markers, mental health and dietary habits in non-conventional professions. METHODS: The sample consisted of 41 female individuals aged between 14 and 24 years, allocated into four groups, control group composed by university students (UG = 11), models (MG = 11), ballet dancers (BG = 11), and athletes' group (AG = 8). Physical fitness outcomes (cardiorespiratory fitness, flexibility, maximal dynamic strength, muscular endurance and body composition); biochemical outcomes (high-density lipoprotein [HDL], low-density lipoprotein [LDL], total cholesterol [TC], fasting glucose [FG], fasting insulin [FI], C-reactive protein [CRP]), diet quality and mental health were evaluated. RESULTS: No impairments were observed in the health markers evaluated among groups, both for health-related physical fitness and biochemical outcomes. However, low levels of bone mineral density (BMD) were observed. Even with statistically significant differences between the groups for chronological age (p = 0.002), menarche (p = 0.004), career length (p = 0.001), height (p = 0.001), body mass index (p = 0.018), waist-to-height ratio (p < 0.001), %Fat (p = 0.020), VO2peak (p = 0.020), maximal dynamic strength of knee extensors (p = 0.031) and elbow flexors (p = 0,001) and flexibility (p < 0.001), all these values are within the normal range for health. CONCLUSION: The professions analyzed do not seem to interfere in the physical fitness and cardiometabolic health of the girls assessed. However, we identified that exposure to these profession can impair mental health (depressive symptoms in 100% of participants) and body composition (BMD 63% of participants).


Assuntos
Aptidão Cardiorrespiratória , Doenças Cardiovasculares , Adolescente , Adulto , Composição Corporal , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Criança , Feminino , Humanos , Aptidão Física , Fatores de Risco , Adulto Jovem
11.
Br J Nutr ; 128(10): 1975-1989, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-34915947

RESUMO

The purpose of the study was to verify the effect of 4 weeks of a high-fructose diet (HFD) associated with aerobic training on the risk factors for cardiometabolic diseases. Twenty-one young adults were randomised into three groups: HFD (HFD: 1 g/kg body weight of fructose/day), high-glucose diet (HGD: 1 g/kg body weight of glucose/day) and high-fructose diet and exercise (HFDE: 1 g/kg body weight of fructose/day + 3 weekly 60-minute sessions of aerobic exercise). Before and after the 4 weeks of the intervention, blood samples were taken and flow-mediated dilatation, insulin resistance index, pancreatic beta cell functional capacity index, insulin sensitivity index and 24-h blood pressure were evaluated. HFD showed an increase in uric acid concentrations (P = 0·040), and HGD and HFDE groups showed no changes in this outcome between pre- and post-intervention; however, the HFDE group showed increased uric acid concentrations from the middle to the end of the intervention (P = 0·013). In addition, the HFD group showed increases in nocturnal systolic blood pressure (SBP) (P = 0·022) and nocturnal diastolic blood pressure (DBP) (P = 0·009). The HGD group exhibited decreases in nocturnal SBP (P = 0·028) and nocturnal DBP (P = 0·031), and the HFDE group showed a decrease in 24-h SBP (P = 0·018). The consumption of 1 g/kg of fructose per day may increase uric acid concentrations and blood pressure in adults. Additionally, aerobic exercises along with fructose consumption attenuate changes in uric acid concentrations and prevent impairment in nocturnal blood pressure.


Assuntos
Glicemia , Ácido Úrico , Humanos , Adulto Jovem , Pressão Sanguínea , Frutose/efeitos adversos , Dieta , Glucose/farmacologia , Exercício Físico , Peso Corporal
12.
Life (Basel) ; 11(11)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34833020

RESUMO

BACKGROUND: Reduced glutathione (GSH) is one of the main thiols involved in antioxidant defense. Changes in circulatory levels of GSH during exercise are associated with hyperthermia and dehydration. The mechanisms by which these alterations occur are not entirely known. We hypothesize that erythrocytes could be an important source of circulatory GSH during heat stress conditions. We performed two separate experiments to address this hypothesis. METHODS: In the first experiment, we sought to investigate the impact of exercise in the heat and dehydration on erythrocyte levels of GSH. A total of 10 men performed 60 min of cycling at 60% VO2peak in the heat (38.0 ± 0.9 °C) or in a control temperate environment (23.0 ± 1.0 °C), both with and without dehydration. Relative humidity ranged from 50 to 70%. Blood samples were taken before and after exercise to measure GSH and oxidized (GSSG) glutathione. In the second experiment, erythrocytes were isolated from blood samples taken at rest and heated in vitro to determine the impact of heat on erythrocyte glutathione content. Tubes with erythrocytes were exposed to water baths at different temperatures; one tube was exposed to a water bath at 35 °C and the other tube to a water bath at 41 °C for a period of 30 min. After exposure to heat, plasma and erythrocytes were extracted for GSH and GSSG analyses. RESULTS: Dehydration decreased circulatory GSH, regardless of ambient temperature (temperate and heat decreased 15.35% and 30.31%, respectively), resulting in an altered redox balance. Heat increased GSH levels in vitro. CONCLUSION: Our data suggest that dehydration decreases circulatory GSH levels regardless of environmental temperature. In addition, in vitro data suggests that erythrocytes may contribute to the release of GSH during exposure to heat stress.

13.
J Therm Biol ; 99: 102943, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34420607

RESUMO

BACKGROUND: Hyperthermia, induced by exercise in the heat, alters the redox status. The physiological significance of these observations remains uncertain but may justify why the consequences of exercising in the heat span from positive health adaptations to negative and even lethal outcomes. Here, we conducted a systematic review to investigate the redox responses during acute exercise in the heat in healthy adults. METHODS: We searched MEDLINE, Cochrane Wiley, ClinicalTrials.gov, PEDRO and LILACS for clinical trials investigating pro- and antioxidant responses to exercise associated with hyperthermia and/or sweat-induced dehydration in healthy young individuals. Two independent reviewers extracted data and assessed the quality of the included studies. RESULTS: A total of 1,014 records were selected, nine full papers were evaluated for eligibility, and eight studies met the inclusion criteria. Overall, results show that hyperthermia promotes oxidative stress both at the tissue level and in the circulation. Exercising in the heat heightens endogenous antioxidant defense systems, attenuating the negative effects of hyperthermia on oxidative damage. Studies also indicate that sweat-induced dehydration promotes oxidative stress, which is attenuated by rehydration. CONCLUSION: These findings suggest that changes in redox status play a role in determining whether an acute bout of exercise in the heat lead to adaptive or maladaptive outcomes.


Assuntos
Exercício Físico/fisiologia , Hipertermia/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Desidratação/metabolismo , Humanos , Oxirredução
14.
Exp Physiol ; 106(4): 1024-1037, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33624912

RESUMO

NEW FINDING: What is the central question of this study? How does moderate-intensity aerobic exercise affect the behaviour of purinergic enzymes in sedentary, overweight and physically active subjects? What is the relationship between purinergic and inflammatory responses triggered by exercise? What is the main finding and its importance? Moderate-intensity aerobic exercise modifies the activity of purinergic enzymes and the levels of nucleotides and nucleosides. These results are similar in subjects with different biological characteristics. 5'-Nucleotidase activity and adenosine levels are associated with inflammatory responses. This study suggests that a purinergic pathway is related to the inflammatory responses triggered by exercise. ABSTRACT: Purinergic signalling is a mechanism of extracellular communication that modulates events related to exercise, such as inflammation and coagulation. Herein, we evaluated the effects of acute moderate-intensity exercise on the activities of purinergic enzymes and plasma levels of adenine nucleotides in individuals with distinct metabolic characteristics. We analysed the relationship between purinergic parameters, inflammatory responses and cardiometabolic markers. Twenty-four healthy males were assigned to three groups: normal weight sedentary (n = 8), overweight sedentary (n = 8) and normal weight physically active (n = 8). The volunteers performed an acute session of moderate-intensity aerobic exercise on a treadmill at 70% of V̇O2peak ; blood samples were drawn at baseline, immediately post-exercise and at 1 h post-exercise. Immediately post-exercise, all subjects showed increases in ATP, ADP, AMP and p-nitrophenyl thymidine 5'-monophosphate hydrolysis, while AMP hydrolysis remained increased at 1 h after exercise. High-performance liquid chromatography analysis demonstrated lower levels of ATP and ADP at post- and 1 h post-exercise in all groups. Conversely, adenosine and inosine levels increased at post-exercise, but only adenosine remained augmented at 1 h after exercise in all groups. With regard to inflammatory responses, the exercise protocol increased tumour necrosis factor α (TNF-α) and interleukin 8 (IL-8) concentrations in all subjects, but only TNF-α remained elevated at 1 h after exercise. Significant correlations were found between the activity of 5'-nucleotidase, adenosine levels, V̇O2peak , triglyceride, TNF-α and IL-8 levels. Our findings suggest a purinergic signalling pathway that participates, at least partially, in the inflammatory responses triggered by acute moderate-intensity exercise. The response of soluble nucleotidases to acute moderate exercise appears to be similar between subjects of different biological profiles.


Assuntos
Exercício Físico , Sobrepeso , Adenosina , Exercício Físico/fisiologia , Teste de Esforço , Humanos , Inflamação , Masculino
15.
Clin Nutr ESPEN ; 41: 160-167, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33487260

RESUMO

INTRODUCTION: Persistent episodes of postprandial hyperlipemia (PPL) and hyperglycemia (PPG) are considered risk factors for coronary heart disease (CHD) and premature death; whereas physical exercise improves lipid profile and glucose tolerance thus decreasing cardiovascular risks. OBJECTIVE: To investigate the effects of low-intensity fasted aerobic exercise on the magnitude of the PPL and PPG responses to meals with different energy content, in normal and obese subjects. METHODS: The study used a randomized crossover design. Twenty-one male (Lean: n = 9, BMI: 24.3 ± 2.2; and obese: n = 12, BMI 32.31 ± 2.1) volunteers aged 20-30 years, performed three interventions, separated by 7 days each: (i) 45 min at rest and isocaloric high-fat meal (60% lipids, 30% carbohydrates and 10% protein); (ii) fasted low-intensity aerobic exercise (50% VO2max) for 45 min followed by an isocaloric or (iii) calorie deficit high-fat meal. Subjects were serially assessed for blood triglycerides, and glucose levels. RESULTS AND CONCLUSIONS: Low-intensity fasted aerobic exercise had no acute effect on PPL in lean and obese subjects. Glucose concentrations were reduced only in lean subjects. There is a significant difference in PPL values when comparing lean to obese subjects, implying that the nutritional status influences lipid and carbohydrate after fasted low-intensity aerobic exercise. Registered under ClinicalTrials.gov Identifier no. NCT00929890.


Assuntos
Glicemia , Hiperlipidemias , Estudos Cross-Over , Exercício Físico , Humanos , Masculino , Refeições , Obesidade
16.
J Sports Sci ; 39(12): 1348-1355, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33459175

RESUMO

The objective of this study was to evaluate effects of photobiomodulation therapy (PBMT) on the 3000 m running performance (primary outcome), running economy (RE), metabolic cost and ratings of perceived exertion during running (secondary outcomes). Twenty male endurance athletes performed 4-min treadmill rectangular test at 12 km.h-1 monitored by a gas analyser. After that, PBMT or placebo in each lower limb was applied, followed performed a maximum test of 3000 m. Immediately after 3000 m test, the athletes repeated the treadmill test. Another application of PBMT/placebo was done after the treadmill test, and athletes went back to the laboratory 24 h later to repeat the treadmill test. After a 72 h interval, athletes repeated all procedures with another treatment intervention (PBMT/placebo). Athletes performed the 3000 m running test ~7s faster when treated with PBMT with similar effort score compared placebo condition. The RE remains unchanged immediately post 3000 m running test, nonetheless RE measured post-24 h improved by 5% with PBMT application without changes in metabolic cost. The PBMT pre- and post-conditioning enhanced the 3000 m running performance and improved RE 24 h following the 3000 m test. However, no changes on ratings of perceived exertion and metabolic cost with the application of PBMT.


Assuntos
Terapia com Luz de Baixa Intensidade , Resistência Física/efeitos da radiação , Corrida/fisiologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Metabolismo Energético/efeitos da radiação , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio , Percepção/efeitos da radiação , Esforço Físico/efeitos da radiação
17.
Diabetes Care ; 44(1): 240-247, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33184152

RESUMO

OBJECTIVE: To investigate physiological responses to cardiopulmonary exercise (CPX) testing in adults with type 1 diabetes compared with age-, sex-, and BMI-matched control participants without type 1 diabetes. RESEARCH DESIGN AND METHODS: We compared results from CPX tests on a cycle ergometer in individuals with type 1 diabetes and control participants without type 1 diabetes. Parameters were peak and threshold variables of VO2, heart rate, and power output. Differences between groups were investigated through restricted maximum likelihood modeling and post hoc tests. Differences between groups were explained by stepwise linear regressions (P < 0.05). RESULTS: Among 303 individuals with type 1 diabetes (age 33 [interquartile range 22; 43] years, 93 females, BMI 23.6 [22; 26] kg/m2, HbA1c 6.9% [6.2; 7.7%] [52 (44; 61) mmol/mol]), VO2peak (32.55 [26.49; 38.72] vs. 42.67 ± 10.44 mL/kg/min), peak heart rate (179 [170; 187] vs. 184 [175; 191] beats/min), and peak power (216 [171; 253] vs. 245 [200; 300] W) were lower compared with 308 control participants without type 1 diabetes (all P < 0.001). Individuals with type 1 diabetes displayed an impaired degree and direction of the heart rate-to-performance curve compared with control participants without type 1 diabetes (0.07 [-0.75; 1.09] vs. 0.66 [-0.28; 1.45]; P < 0.001). None of the exercise physiological responses were associated with HbA1c in individuals with type 1 diabetes. CONCLUSIONS: Individuals with type 1 diabetes show altered responses to CPX testing, which cannot be explained by HbA1c. Intriguingly, the participants in our cohort were people with recent-onset type 1 diabetes; heart rate dynamics were altered during CPX testing.


Assuntos
Diabetes Mellitus Tipo 1 , Teste de Esforço , Adulto , Exercício Físico , Tolerância ao Exercício , Feminino , Humanos , Consumo de Oxigênio , Adulto Jovem
19.
Crit Rev Food Sci Nutr ; 61(17): 2863-2875, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32662279

RESUMO

Meal timing may be a critical modulator of health outcomes due to complex interactions between circadian biology, nutrition and human metabolism. As such, approaches that aim to align food consumption with endogenous circadian rhythms are emerging in recent years. Time-restricted eating (TRE) consists of limiting daily nutrient consumption to a period of 4 to 12 hours in order to extend the time spent in the fasted state. TRE can induce positive effects on the health of individuals with overweight and obesity, including sustained weight loss, improvement in sleep patterns, reduction in blood pressure and oxidative stress markers and increased insulin sensitivity. However, it is not fully clear whether positive effects of TRE are due to reduced energy intake, body weight or the truncation of the daily eating window. In addition, null effects of TRE in some populations and on some parameters of cardiometabolic health have been documented. Some evidence indicates that greater promotion of health via TRE may be achieved if the nutrient intake period occurs earlier in the day. Despite some promise of this dietary strategy, the effects of performing TRE at different times of the day on human cardiometabolic health, as well as the safety and efficacy of this dietary approach in individuals with cardiometabolic impairments, need to be evaluated in additional controlled and long-term studies.


Assuntos
Ritmo Circadiano , Jejum , Relógios Biológicos , Peso Corporal , Ingestão de Alimentos , Ingestão de Energia , Comportamento Alimentar , Humanos
20.
Res Q Exerc Sport ; 92(3): 453-459, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32493165

RESUMO

Several authors report health improvements with training based on the Pilates Method; however, no explicit analysis has been performed on cardiorespiratory effects after Method exclusive training. Purpose: The purpose of this study was to evaluate the effects of 15 weeks of Pilates training on cardiorespiratory fitness in young, sedentary women. Method: A total of 13 sedentary women 21-35 years volunteered and signed an informed consent for the observational study of a single group, performing control-test, pre- and post-exercise measurements. The Pilates program was conducted for 15 weeks, with two 50-min sessions per week. Cardiorespiratory responses were assessed using an open circuit ergospirometry system by gas analyzer (MGC, model CPX/D). Results: During the 15-week program, statistically significant advances were observed in maximum oxygen consumption F (1.25; 13.78) = 18.95; p =.001; ω2 =.858 with large effect size (r =.81; p <.001), first ventilatory threshold F (1.19; 13.15) = 20.43; p =.001; ω2 =.034 with large effect size (r =.77; p <.05) and second ventilatory threshold F (1.18; 13.00) = 24.56; p =.001 also presenting a large effect size (r =.85; p <.05). Conclusion: These results indicate that practicing Pilates for 30 × 50 min sessions had a positive influence on cardiorespiratory parameters in healthy sedentary women with low respiratory capacities.


Assuntos
Adaptação Fisiológica/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Técnicas de Exercício e de Movimento/métodos , Adulto , Composição Corporal/fisiologia , Feminino , Humanos , Consumo de Oxigênio/fisiologia , Adulto Jovem
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