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The aim of this study was to compare the effects of continuous-moderate vs. high-intensity interval aerobic training on cardiovascular and metabolic parameters in ovariectomized high-fat-fed mice. C57BL/6 female ovariectomized were divided into four groups (n=8): low-fat-fed sedentary (SLF); high-fat-fed sedentary (SHF); high-fat-fed moderate-intensity continuous trained (MICT-HF); and high-fat-fed high-intensity interval aerobic trained (HIIT-HF). The high-fat diet lasted 10 weeks. Ovariectomy was performed in the fourth week. The exercise training was carried out in the last four weeks of protocol. Fasting glycemia, oral glucose tolerance, arterial pressure, baroreflex sensitivity, and cardiovascular autonomic modulation were evaluated. Moderate-intensity continuous training prevented the increase in arterial pressure and promoted a reduction in HR at rest, associated with an improvement in the sympathovagal balance in MICT-HF vs. SHF. The high-intensity interval training reduced blood glucose and glucose intolerance in HIIT-HF vs. SHF and MICT-HF. In addition, it improved sympathovagal balance in HIIT-HF vs. SHF. Moderate-intensity continuous training was more effective in promoting cardiovascular benefits, while high-intensity interval training was more effective in promoting metabolic benefits.
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Doenças Cardiovasculares , Treinamento Intervalado de Alta Intensidade , Camundongos , Animais , Feminino , Camundongos Obesos , Camundongos Endogâmicos C57BL , Glicemia/metabolismo , Coração , Treinamento Intervalado de Alta Intensidade/métodosRESUMO
The present study aimed to compare the morphological response induced by different ladder-based resistance training (LRT) protocols on the peripheral nerve ultrastructure of young adult Wistar rats. Twenty-nine rodents were distributed into groups: control (CON), submaximal (SUBMAX [6 climbs/session, moderate intensity, 3x/week]) and maximum (MAX [> 4 climbs/session, maximum intensity, 3x/week]) LRT. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, the myelinated fibers and axons, myelin sheath thickness, and unmyelinated axons were statistically greater in the SUBMAX and MAX. The MAX group had greater unmyelinated fibers than SUBMAX. The Schwann cell (SC) nuclei diameter was statistically larger in the SUBMAX than the CON. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. In the sciatic nerve, the myelinated fibers, myelinated and unmyelinated axons, and myelin sheath thickness were statistically greater in the SUBMAX and MAX. The SUBMAX and MAX had more SC at the nuclei level than CON. The SC nuclei were statistically larger in the SUBMAX and MAX. The number of microtubules and neurofilaments was statistically higher in the SUBMAX and MAX. Total training load and total load per climb were not different between groups. The SUBMAX and MAX statistically increased maximum carried load (ML). In conclusion, the different LRT protocols induced similar morphological responses in radial and sciatic nerves, probably due to load progression and equal total load volume.
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Treinamento Resistido , Animais , Humanos , Bainha de Mielina , Nervo Radial , Ratos , Ratos Wistar , Nervo IsquiáticoRESUMO
To analyze the morphological response induced by high-volume, high-intensity ladder-based resistance training (LRT) on the ultrastructure of the radial (forelimb) and sciatic (hindlimb) nerves of adults Wistar rats. Twenty rats were equally distributed into groups: sedentary (SED) and LRT. After the rodents were subjected to the maximum load (ML) carrying test, the LRT group performed 6-8 progressive climbs (2 × 50% ML, 2 × 75% ML, 2 × 100% ML, and 2 × 100% ML + 30 g) three times per week. After 8 weeks, the radial and sciatic nerves were removed and prepared for transmission electron microscopy. In the radial nerve, myelinated axons cross-sectional area (CSA), unmyelinated axons CSA, myelin sheath thickness, and Schwann cells nuclei area were statistically larger in the LRT group than SED (p < 0.05). Also, the number of microtubules and neurofilaments per field were statistically higher in the LRT group than in SED (p < 0.01). For sciatic nerve, myelinated fibers CSA, unmyelinated axons CSA, myelin sheath thickness, Schwann cells nuclei area, and the number of neurofilaments per field were statistically larger in the LRT group compared to the SED group (p < 0.05). LRT with high-volume and high-intensity effectively induce similar changes in adult Wistar rats' radial and sciatic nerves' ultrastructure.
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Treinamento Resistido , Animais , Membro Anterior , Membro Posterior , Humanos , Bainha de Mielina , Nervos Periféricos , Ratos , Ratos Wistar , Nervo IsquiáticoRESUMO
PURPOSE: The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance and physiological responses during high-intensity intermittent exercise (HIIE). METHOD: Thirteen physically active men (age = 24.4 ± 4.0 years; height = 176.4 ± 6.9 cm; body mass = 78.7 ± 13.8 kg; running training per week = 3.9 ± 0.9 h) performed an incremental running test to determine peak oxygen uptake ([Formula: see text]) and the speed associated with [Formula: see text] (s[Formula: see text]). Thereafter, subjects completed two randomized, double-blind HIIE (15s:15 s at 120% s[Formula: see text]) trials 45-min after consuming capsaicin (12 mg) or an isocaloric placebo. Time to exhaustion, blood lactate concentration, oxygen consumption during and 20 min post-exercise, energy expenditure, time spent above 90% of [Formula: see text], and the rate of perceived exertion were evaluated. RESULTS: There was no difference between capsaicin and placebo for any variable except time to exhaustion [capsaicin: 1530 ± 515 s (102 efforts) vs placebo: 1342 ± 446 s (89 efforts); p < 0.001]. CONCLUSION: In conclusion, capsaicin supplementation increased time to exhaustion in high-intensity intermittent exercise without modifying the metabolic response of exercise or the rate of perceived exertion in physically active men. Capsaicin could be used to increase the training load during specific exercise training sessions.
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Capsaicina/farmacologia , Exercício Físico/fisiologia , Treinamento Intervalado de Alta Intensidade , Consumo de Oxigênio/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Adulto , Desempenho Atlético/fisiologia , Tolerância ao Exercício/efeitos dos fármacos , Humanos , Masculino , Oxigênio/metabolismo , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Corrida/fisiologiaRESUMO
Inflammatory markers are increased systematically and locally (e.g., skeletal muscle) in stroke patients. Besides being associated with cardiovascular risk factors, proinflammatory cytokines seem to play a key role in muscle atrophy by regulating the pathways involved in this condition. As such, they may cause severe decrease in muscle strength and power, as well as impairment in cardiorespiratory fitness. On the other hand, physical exercise (PE) has been widely suggested as a powerful tool for treating stroke patients, since PE is able to regenerate, even if partially, physical and cognitive functions. However, the mechanisms underlying the beneficial effects of physical exercise in poststroke patients remain poorly understood. Thus, in this study we analyze the candidate mechanisms associated with muscle atrophy in stroke patients, as well as the modulatory effect of inflammation in this condition. Later, we suggest the two strongest anti-inflammatory candidate mechanisms, myokines and the cholinergic anti-inflammatory pathway, which may be activated by physical exercise and may contribute to a decrease in proinflammatory markers of poststroke patients.
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Exercício Físico , Inflamação/patologia , Músculo Esquelético/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Anti-Inflamatórios/uso terapêutico , Colinérgicos/química , Humanos , Camundongos , Atrofia Muscular/patologia , Atrofia Muscular/fisiopatologia , Ratos , Fatores de RiscoRESUMO
BACKGROUND: We evaluated cardiac autonomic modulation in women with chronic ischemic stroke (at least 4 years post-stroke) at rest and in response to submaximal exercise test. METHODS: Fourteen post-stroke women (S group) and 10 healthy women (C group) participated in this study. Autonomic modulation (using linear and nonlinear analysis), blood pressure and metabolic variables at rest were evaluated immediately after the exercise test and during the recovery period (20 min). All participants underwent submaximal exercise test on cycle ergometer with gas analysis. RESULTS: At rest, the S group displayed higher lactate concentration, systolic (SBP) and diastolic blood pressure (DBP) values when compared to C group. Furthermore, the S group had lower heart rate variability (HRV) in time domain (SDNN: S = 30 ± 5 vs. 40 ± 8 ms; rMSSD: S = 14 ± 2 vs. C = 34 ± 3 ms), decreased high frequency band of pulse interval (S = 8.4 ± 2 vs. 33.1 ± 9 %) and 2V pattern of symbolic analysis (S = 17.3 ± 1 vs. 30 ± 3 %) (both indicators of cardiac vagal modulation) when compared to C group. Immediately after exercise, S group presented higher values of lactate, SBP, DBP and double product when compared to C group, as well as decreased heart rate recovery (HRR) measured at the first, second and third minutes. At recovery time, all HRV parameters in time and frequency domains improved in the S group; however, HF band remained lower when compared to C group. CONCLUSIONS: After the exercise test, women with chronic stroke presented reduced heart rate variability, reduced cardiac vagal modulation, as well as reduced HRR, while displayed an improvement of heart rate variability and cardiac vagal modulation when compared to their baseline. These results reinforce the importance of a physically active lifestyle for cardiovascular autonomic disorders observed in chronic stroke women.
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Teste de Esforço/métodos , Coração/inervação , Acidente Vascular Cerebral/fisiopatologia , Nervo Vago/fisiopatologia , Idoso , Glicemia/metabolismo , Pressão Sanguínea/fisiologia , Doença Crônica , Feminino , Seguimentos , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Pessoa de Meia-IdadeRESUMO
UNLABELLED: Changes in the heart compartments that leads to pathological cardiac hypertrophy can be related to testosterone reduction in aging males since heart cells are susceptible to androgens. Resistance exercise delays the changes of aging. AIM: This study aimed to analyze alterations of the left ventricle of aged rats subjected to resistance exercise with administration of testosterone. METHODS: Wistar rats were divided into five groups: C Group (control), S Group (sedentary), ST Group (sedentary treated with testosterone), T Group (trained) and TT Group (trained and treated with testosterone), strength training protocol and testosterone treatment were 16 weeks long. All groups were sacrificed at 16 months except for C group, sacrificed at 13 months. RESULTS: There was no change in the weight of the heart or the left ventricle between the groups. ST group showed increase in Nv [cap] density of capillaries and collagen, with no differences in interstitial space. Both trained groups (T and TT) showed increase in the numerical density of capillaries (Nv [cap]) and in the interstitial space, with no changes in collagen. CONCLUSION: Resistance exercise combined with testosterone triggered a response of compensatory adjustment in the increase of Nv [cap], collagen and interstitial space, increasing perfusion and nutrition to the heart.
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Capilares/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Treinamento Resistido , Testosterona/farmacologia , Animais , Capilares/fisiologia , Masculino , Condicionamento Físico Animal/fisiologia , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologiaRESUMO
The aim of this study was to evaluate the effects of exercise training (ET, 50-70% of VO2 max, 5 days/week) and detraining (DT) on inflammatory and metabolic profile after myocardial infarction (MI) in rats. Male Wistar rats were divided into control (C, n = 8), sedentary infarcted (SI, n = 9), trained infarcted (TI, n = 10; 3 months of ET), and detrained infarcted (DI, n = 11; 2 months of ET + 1 month of DT). After ET and DT protocols, ventricular function and inflammation, cardiovascular autonomic modulation (spectral analysis), and adipose tissue inflammation and lipolytic pathway were evaluated. ET after MI improved cardiac and vascular autonomic modulation, and these benefits were correlated with reduced inflammatory cytokines on the heart and adipose tissue. These positive changes were sustained even after 1 month of detraining. No expressive changes were observed in oxidative stress and lipolytic pathway in experimental groups. In conclusion, our results strongly suggest that the autonomic improvement promoted by ET, and maintained even after the detraining period, was associated with reduced inflammatory profile in the left ventricle and adipose tissue of rats subjected to MI. These data encourage enhancing cardiovascular autonomic function as a therapeutic strategy for the treatment of inflammatory process triggered by MI.
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Sistema Nervoso Autônomo/imunologia , Sistema Nervoso Autônomo/metabolismo , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/metabolismo , Condicionamento Físico Animal , Animais , Frequência Cardíaca/fisiologia , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/terapia , Masculino , Infarto do Miocárdio/terapia , Ratos , Ratos WistarRESUMO
Scientific evidence regarding the effect of different ladder-based resistance training (LRT) protocols on the morphology of the neuromuscular system is scarce. Therefore, the present study aimed to compare the morphological response induced by different LRT protocols in the ultrastructure of the tibial nerve and morphology of the motor endplate and muscle fibers of the soleus and plantaris muscles of young adult Wistar rats. Rats were divided into groups: sedentary control (control, n = 9), a predetermined number of climbs and progressive submaximal intensity (fixed, n = 9), high-intensity and high-volume pyramidal system with a predetermined number of climbs (Pyramid, n = 9) and lrt with a high-intensity pyramidal system to exhaustion (failure, n = 9). myelinated fibers and myelin sheath thickness were statistically larger in pyramid, fixed, and failure. myelinated axons were statistically larger in pyramid than in control. schwann cell nuclei were statistically larger in pyramid, fixed, and failure. microtubules and neurofilaments were greater in pyramid than in control. morphological analysis of the postsynaptic component of the plantar and soleus muscles did not indicate any significant difference. for plantaris, the type i myofibers were statistically larger in the pyramid and fixed compared to control. the pyramid, fixed, and failure groups for type ii myofibers had larger csa than control. for soleus, the type i myofibers were statistically larger in the pyramid than in control. pyramid and fixed had larger csa for type ii myofibers than control and failure. the pyramid and fixed groups showed greater mass progression delta than the failure. We concluded that the LRT protocols with greater volume and progression of accumulated mass elicit more significant changes in the ultrastructure of the tibial nerve and muscle hypertrophy without endplate changes.
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Introduction: The purpose of this study was to investigate the ideal training load to be applied during periods of fixture congestion to ensure an adequate dose-response effect for performance maintenance. Methods: Match performance data and corresponding pre-match training load sessions (both N = 498 match performance cases and training-block session cases) were collected (with the catapult system, VECTOR7) from 36 male professional soccer players (23.5 ± 5.2 years; 178 ± 4 cm; 75.5 ± 6.0 kg) belonging to the Brazilian First Division team during the 2022 season. The following data were collected in match and training sessions: jump, acceleration, deceleration, and change of direction (COD); running distance producing metabolic power at different intensities (>20, >20-35, >35-45, >45-55, and >55 W kg-1), total distance (m), relative distance (m/min), running distance at different speeds (>20, >25, and >30 km/h), number of sprints (running >25 km/h), and maximum speed (km/h). Mixed linear model (MLM), decision tree regression (DTR), and cluster K means model (SPSS v.26) approach were performed to identify the most critical variables (and their respective load) in the training sessions that could explain the athlete's match performance. Results: MLM and DTR regression show that training load significantly affects game performance in a specific way. According to the present data, an interference phenomenon can occur when a high load of two different skills (running in a straight line vs COD, deceleration, and jumping) is applied in the same training block of the week. The cluster approach, followed by a chi-squared test, identified significant associations between training load and athlete match performance in a dose-dependent manner. Discussion: The high load values described here have a beneficial effect on match performance, despite the interference between stimuli discussed above. We present a positive training load from a congested season from the Brazilian First Division team. The study suggests that an interference effect occurs when high physical training loads are applied to different specific physical skills throughout the season.
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We evaluate the effects of detraining (DT, for 1 month) on the left ventricular (LV) remodeling and function, hemodynamic and baroreflex sensitivity (BRS), as well as on mortality rate of infarcted (MI) rats after 3 months of exercise training (ET, 50-70 % of VO2max). Male Wistar rats were divided into five groups: control (C, n = 10), untrained-infarcted (UI, n = 15), trained-infarcted (TI, n = 12), untrained-infarcted plus 1 month (UI-1, n = 15) and detrained-infarcted 1 month (DI-1, n = 15). LV function was evaluated by echocardiography at the initial and final of the protocols. After following, ET and/or DT protocols, hemodynamic and BRS [by tachycardic (TR) and bradycardic (BR) responses] were assessed. TI group displayed increased VO2max in comparison with UI and DI-1 groups; however, DI-1 values remained increased compared to UI-1 group. MI area was reduced by ET and maintained after DT. Ejection fraction (TI = 60 ± 2 and DI-1 = 61 ± 2 % vs. UI = 41 ± 1 and UI-1 = 37 ± 3 %), E/A ratio (TI = 1.6 ± 0.1 and DI-1 = 1.9 ± 0.1 vs. UI = 2.9 ± 0.2 and UI-1 = 2.9 ± 0.3), TR (TI = 3.3 ± 0.3 and DI-1 = 3.3 ± 0.4 vs. UI = 1.7 ± 0.1 and UI-1 = 1.6 ± 0.1 bpm/mmHg) and BR (TI = -2.2 ± 0.1 and DI-1 = -2.0 ± 0.1 vs. UI = -1.3 ± 0.09 and UI-1 = -1.2 ± 0.09 bpm/mmHg) were improved by ET and maintained after DT in comparison with untrained rats. These changes resulted in mortality reduction in the TI (8 %) and DI-1 groups (13 %) compared with the UI (46 %) and UI-1 (53 %) groups. These findings indicate that ET is not only an effective tool in the management of cardiovascular and autonomic MI derangements, but also that these positive changes were maintained even after 1 month of DT in rats.
Assuntos
Hemodinâmica , Infarto do Miocárdio/fisiopatologia , Esforço Físico , Função Ventricular , Animais , Barorreflexo , Masculino , Infarto do Miocárdio/terapia , Ratos , Ratos Wistar , Treinamento ResistidoRESUMO
STUDY OBJECTIVES: The purpose of the present study was to evaluate the relationship between sleep duration and dietary habits in elderly obese patients treated at an institute of cardiology. METHODS: The fifty-eight volunteers were elderly patients with obesity (classified as obese according to BMI) of both genders, between 60 and 80 years of age. All participants were subjected to assessments of food intake, anthropometry, level of physical activity, and duration of sleep. RESULTS: The men had significantly greater weight, height, and waist circumference than women. Sleep durations were correlated with dietary nutrient compositions only in men. We found a negative association between short sleep and protein intake (r = -0.43; p = 0.02), short sleep and monounsaturated fatty acids intake (r = -0.40; p = 0.03), and short sleep and cholesterol dietary intake (r = -0.50; p = 0.01). CONCLUSIONS: We conclude that mainly in men, volunteers that had short sleep duration showed a preference for high energy-density as fatty food, at least in part, may explain the relationship between short sleep duration and the development of metabolic abnormalities.
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Ingestão de Energia , Obesidade/complicações , Transtornos do Sono-Vigília/etiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Gorduras na Dieta/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We compared the effects of two ladder-based resistance training (LRT) protocols on the skeletal muscle morphology (biceps brachialis and plantaris) of Wistar rats. Also, we correlated the training parameters with the muscle fiber cross-sectional area (fCSA). After maximum load tests (ML), twenty-nine young adult Wistar rats were divided into: CONTROL (n = 9), LIMITED (n = 10, 6-8 climb [2 × 50 %ML, 2 × 75 %ML, 2 × 100 %ML, and 2 × 100 %ML+30 g]) and UNLIMITED (n = 10, ≥4 climbs [50 %ML, 75 %ML, 90 %ML, 100 %ML + 30 g until failure) LRT. After eight weeks, the main results were: 1) For biceps brachialis, the type I, IIa, and mean fCSA was statistically larger in the LIMITED than CONTROL. The nuclei/fiber ratio was statistically higher in the LIMITED and UNLIMITED. The correlations found between total load, absolute delta load, and relative load and fCSA were moderate. 2) For plantaris, the type I, IIa, IIx/b, and mean fCSA was statistically larger in the LIMITED than CONTROL. The type IIa, IIx/b, and mean fCSA was statistically larger in the UNLIMITED than CONTROL. The nuclei/fiber ratio was statistically higher in both trained groups than CONTROL. The correlation between the climbing number, total load, and the fCSA was moderate. The correlation between delta absolute load and fCSA was strong. We concluded that rodents submitted to high-intensity, high-volume LRT, but limited climbing volume per session, presented more significant type I, IIa, IIx/b, and mean fCSA, higher nuclei/fiber ratio, and greater maximum carrying capacity. Also, muscle hypertrophy correlated positively with the load progression, training volume, and total load.
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Treinamento Resistido , Animais , Humanos , Hipertrofia , Músculo Esquelético , Ratos , Ratos Wistar , Treinamento Resistido/métodos , RoedoresRESUMO
To investigate the effects of the previous administration of testosterone propionate (TP) on the morphology of the gastrocnemius muscle of Wistar rats submitted to ladder-based resistance training (LRT). Twenty-eight rats were divided equally into groups: initial control (CI), 4-week TP (CT4), 4-week TP + LRT (TRT), and placebo + LRT (RT). The rats from the CT4 and TRT groups were treated with TP for four weeks (10 mg/kg/week). TRT and RT trained for ten weeks. The rodents were euthanized at the end of the experiment, and gastrocnemius muscle, prostate, and left and right testicles were collected. There was no statistical difference between the RT and TRT for final volume load. The prostate mass of the TRT and RT groups was statistically heavier than the CT4 group (P < 0.01). The TRT group's prostate/body mass ratio was statistically different from the CT4 group (P < 0.05). The TRT group was shown to have larger type I, type II, and mean fCSA fibers than all other groups (P < 0.001). Regarding the nuclei/fiber ratio (N/f), the CT4, RT, and TRT groups had higher values than CI (P < 0.01). In addition, the RT group showed a higher N/f ratio than CT4 (P < 0.001) but lower than TRT (P < 0.001). In conclusion, short-term TP administration before resistance training can elicit a greater N/f ratio and size of the mean fCSA of the Gastrocnemius muscle of young adult Wistar rats than resistance training alone.
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Treinamento Resistido , Propionato de Testosterona , Animais , Humanos , Hipertrofia , Masculino , Músculo Esquelético , Ratos , Ratos Wistar , Testosterona , Propionato de Testosterona/farmacologiaRESUMO
BACKGROUND: Acute capsaicinoid and capsinoid supplementation has endurance and resistance exercise benefits; however, if these short-term performance benefits translate into chronic benefits when combined with resistance training is currently unknown. This study investigated changes of chronic Capsiate supplementation on muscular adaptations, inflammatory response and performance in untrained men. METHODS: Twenty untrained men were randomized to ingest 12 mg Capsiate (CAP) or placebo in a parallel, double-blind design. Body composition and performance were measured at pre-training and after 6 weeks of resistance training. An acute resistance exercise session test was performed pre and post-intervention. Blood samples were collected at rest and post-resistance exercise to analyze Tumor necrosis factor- (TNF-), Soluble TNF- receptor (sTNF-r), Interleukin-6 (IL-6) and Interleukin-10 (IL-10). RESULTS: Exercise and CAP supplementation increased fat-free mass in comparison to baseline by 1.5 kg (P < 0.001), however, the majority of the increase (1.0 kg) resulted from an increase in total body water. The CAP change scores for fat-free mass were significantly greater in comparison to the placebo (CAP ∆%= 2.1 ± 1.8 %, PLA ∆%= 0.7 ± 1.3 %, P = 0.043) and there was a significant difference between groups in the bench press exercise (P = 0.034) with greater upper body strength change score for CAP (∆%= 13.4 ± 9.1 %) compared to placebo (∆%= 5.8 ± 5.2 %), P = 0.041. CAP had no effect on lower body strength and no supplementation interactions were observed for all cytokines in response to acute resistance exercise (P > 0.05). CONCLUSION: Chronic Capsiate supplementation combined with resistance training during short period (6 weeks) increased fat-free mass and upper body strength but not inflammatory response and performance in young untrained men.
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Capsaicina/análogos & derivados , Mediadores da Inflamação/sangue , Força Muscular/efeitos dos fármacos , Treinamento Resistido/métodos , Adulto , Desempenho Atlético , Composição Corporal/efeitos dos fármacos , Água Corporal/efeitos dos fármacos , Água Corporal/metabolismo , Capsaicina/administração & dosagem , Capsaicina/farmacologia , Método Duplo-Cego , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Receptores do Fator de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto JovemRESUMO
BACKGROUND: This study examined the effects of acute supramaximal exercise (approximately 115% VO(2max)) on the blood lipid profile for three different carbohydrate (CHO) storage levels (control, low and high). METHODS: Six male subjects were randomly divided into three different groups: control, low CHO and high CHO. These groups differed in the diet to which the subjects were submitted before each exercise session. The lipid profile [triglycerides (TG), very low-density lipoprotein (VLDL), high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, TG/HDL-C ratio and total cholesterol) was determined at rest, immediately after exercise and 1 h after exercise bouts. RESULTS: The time to exhaustion was lower in the low CHO condition compared with the control and high CHO condition (3.59 +/- 0.72; 2.91 +/- 0.56; and 4.26 +/- 0.69 min; P < 0.05). The energy expenditure (control: 251.1 +/- 56.0 kJ; low CHO: 215.2 +/- 28.6 kJ; and high CHO: 310.4 +/- 64.9 kJ) was significantly different between the low and high CHO conditions (P < 0.05). There were no significant changes in the lipid profile for any of the experimental conditions (control, low and high; P < 0.05). Glucose and insulin levels did not show time-dependent changes in any of the conditions (P > 0.05). CONCLUSIONS: These results indicate that a supramaximal exercise session has no significant effects on lipid metabolism.
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Metabolismo dos Carboidratos/fisiologia , Exercício Físico/fisiologia , Metabolismo dos Lipídeos/fisiologia , Lipoproteínas/sangue , Esforço Físico/fisiologia , Adulto , Metabolismo Energético/fisiologia , Teste de Esforço , Humanos , MasculinoRESUMO
This study investigated the effect of exercise on glutamine metabolism in macrophages of trained rats. Rats were divided into three groups: sedentary (SED); moderately trained (MOD) rats that were swim trained 1 h/day, 5 days/week for 6 weeks; and exhaustively trained (EXT) rats that were similarly trained as MOD for 5 weeks and, in the 6th week, trained in three 1-h sessions/day with 150 min of rest between sessions. The animals swam with a load equivalent to 5.5% of their body weight and were killed 1 h after the last exercise session. Cells were collected, and glutamine metabolism in macrophage and function were assayed. Exercise increased phagocytosis in MOD when compared to SED (34.48 +/- 1.79 vs 15.21 +/- 2.91%, P < 0.05); however, H(2)O(2) production was higher in MOD (75.40 +/- 3.48 nmol h x 10(5) cell(-1)) and EXT (79.20 +/- 1.18 nmol h x 10(5) cell(-1)) in relation to SED (32.60 +/- 2.51 nmol h x 10(5) cell(-1), P < 0.05). Glutamine consumption increased in MOD and EXT (26.53 +/- 3.62 and 19.82 +/- 2.62 nmol h x 10(5) cell(-1), respectively) relative to SED (6.72 +/- 0.57 nmol h x 10(5) cell(-1), P < 0.05). Aspartate increased in EXT (9.72 +/- 1.14 nmol h x 10(5) cell(-1)) as compared to SED (1.10 +/- 0.19 nmol h x 10(5) cell(-1), P < 0.05). Glutamine decarboxylation was increased in MOD (12.10 +/- 0.27 nmol h x 10(5) cell(-1)) and EXT (16.40 +/- 2.17 nmol h x 10(5) cell(-1)) relative to SED (1.10 +/- 0.06 nmol h x 10(5) cell(-1), P < 0.05). This study suggests an increase in macrophage function post-exercise, which was supported by enhanced glutamine consumption and metabolism, and highlights the importance for glutamine after exercise.
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Fadiga/metabolismo , Glutamina/metabolismo , Macrófagos Peritoneais/metabolismo , Fagocitose/fisiologia , Condicionamento Físico Animal/fisiologia , Análise de Variância , Animais , Ácido Aspártico/metabolismo , Teste de Esforço , Ácido Glutâmico/metabolismo , Peróxido de Hidrogênio/metabolismo , Ratos , Ratos Wistar , Descanso/fisiologia , NataçãoRESUMO
ABSTRACT Introduction: The recovery interval (RI) between sets and exercises has received attention from strength training (ST) researchers, to understand the relationship of rest on performance maintenance, especially the total load in a training session. It is known that each individual responds in a specific way to the training stimulus. So, what would be the effect of the different recovery interval strategies on the strength performance? Objective: Compare the different recovery intervals in strength training volume, considering the number of repetitions in healthy adults. Methods: We conducted a systematic review and meta-analysis based on methodological criteria, comparing fixed and self-selected RI on training volume, identified by the number of repetitions performed in a weight training program. Three electronic databases (Pubmed, VHL Virtual Health Library, Ebsco Sportdiscus) were analyzed, combining the expressions "resistance training", "resistance exercise", "strength exercise", "recovery interval", "rest interval", "interval auto suggested", "auto range selected" with "AND" and "OR" combination. Results: Pooled data from five studies showed a large significant effect in favor of the experimental group (>2 minutes) (MD: 1.24; 95%-CI [0.78; 1.71]; z: 5.25, Q:1.08; p < 0.01), since in the studies, recovery interval allowed a greater training volume. Conclusion: Longer RI seems be better, for maintaining total training volume, although there is no consensus for different training objectives against the self-selected RI. Thus, we imagine that this strategy may be important in the organizing a bodybuilding exercise program. Level of Evidence I; Systematic Review and Meta Analysis.
RESUMEN Introducción: El intervalo de recuperación (IR) entre series y ejercicios ha recibido atención por parte de los investigadores del entrenamiento de fuerza (EF), contribuyendo a la comprensión de esta variable en relación con el mantenimiento del rendimiento, especialmente la carga durante el entrenamiento con pesas. Se sabe que cada individuo responde de manera específica al estímulo del entrenamiento, entonces, ¿cuál es el efecto de las diferentes estrategias de intervalos de recuperación sobre el rendimiento de fuerza? Objetivo: Comparar diferentes intervalos de recuperación en entrenamiento de fuerza en volumen de entrenamiento, identificados por el número de repeticiones en musculación en adultos sanos. Métodos: Realizamos una revisión sistemática y un metanálisis basado en criterios metodológicos, comparando IR fijo y autoseleccionado en función del volumen de entrenamiento, identificado por el número de repeticiones realizadas en un programa de entrenamiento con pesas. Se analizaron los registros de tres bases de datos electrónicas (Pubmed, Biblioteca Virtual en Salud de la BVS, Ebsco Sportdiscus), combinando las palabras "entrenamiento de resistencia", "ejercicio de resistencia", "ejercicio de fuerza", "intervalo de recuperación", "intervalo de descanso", "intervalo auto sugerido", "rango automático seleccionado" con la combinación "AND" y "OR". Resultados: Los datos agrupados de cinco estudios mostraron un gran efecto significativo a favor del grupo experimental (> 2 minutos) (DM: 1,24; IC del 95 % [0,78; 1,71]; z: 5,25, Q: 1,08; p < 0,01), ya que, en los estudios en cuestión, este intervalo de recuperación permitió un mayor volumen de entrenamiento. Conclusión: Los intervalos más largos parecen ser mejores, en el volumen total de entrenamiento, aunque no hay consenso para diferentes objetivos de entrenamiento frente al RI autoseleccionado. Por lo tanto, imaginamos que esta estrategia puede ser importante en la organización del programa de ejercicios de musculación. Nivel de Evidencia I; Revisión Sistemática y Meta Análisis.
RESUMO Introdução: O intervalo de recuperação (IR) entre séries e exercícios, tem recebido atenção dos pesquisadores de treinamento de força (TF), contribuindo no entendimento dessa variável em relação a manutenção do rendimento, em especial da carga durante o treinamento de musculação. Sabe-se que cada indivíduo responde de modo específico ao estimulo do treinamento, desta forma, qual o efeito das diferentes estratégias do intervalo recuperação no desempenho da força? Objetivo: Comparar diferentes intervalos de recuperação no treinamento de força no volume de treino, identificado pelo número de repetições na musculação em adultos saudáveis. Métodos: Realizamos, pelos critérios metodológicos, revisão sistemática e meta-análise, comparando o IR fixo e auto selecionado em função do volume de treino, identificado pelo número de repetições realizados em programa de musculação. Foram analisados os registros de três bases de dados eletrônicas (Pubmed, Biblioteca Virtual da Saúde BVS, Ebsco Sportdiscus), combinando as expressões "treinamento de resistência", "exercício resistido", "exercício de força", "intervalo de recuperação", "intervalo de descanso", "intervalo auto sugerido", "intervalo auto selecionado" com combinação "AND" e "OR". Resultados: Os dados reunidos de cinco estudos mostraram um grande efeito significante a favor do grupo experimental (>2 minutos) (MD: 1.24; 95%-IC [0.78; 1.71]; z: 5.25, Q:1.08; p < 0.01), uma vez que nos estudos em questão, esse intervalo de recuperação possibilitou maior volume de treino. Conclusão: Intervalos mais longos parecem ser melhores no volume total do treinamento, embora não haja consenso para diferentes objetivos do treinamento frente ao IR auto selecionado. Dessa forma, imaginamos que essa estratégia possa ser importante na organização do programa de exercício de musculação. Nível de Evidencia I; Revisão Sistemática e Meta Análise.
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The aim of this study was to verify the autonomic modulation and blood pressure after adenosine-5'-triphosphate (ATP) supplementation associated to acute aerobic exercise in hypertensive women. Eleven hypertensive women (age, 61.8±5.0 years) completed a randomized, double blind trial: ATP supplement condition (ATP=400 mg) or placebo. After 30 min of supplementation or placebo intake, the subjects performed 30 min of aerobic exercise (70%-75% of maximum heart rate). The autonomic modulation was assessed by heart rate variability during rest and recovery (postexercise until 30 min of recovery), the square root of the mean squared difference between adjacent RR intervals (RMSSD), standard deviation of successive values (SDNN), low frequency (LF) and high frequency (HF) were measured. The blood pressure (systolic blood pressure [SBP] and diastolic blood pressure, mmHg) were recorded at rest, immediately postexercise, post-10, post-20, and post-30 min after exercise. For RMSSD, there was statistically significant difference during recovery, with higher RMSSD for ATP compared to placebo (rest=16.4±8.5 vs. placebo=11.6±4.0; ATP=18.5±9.7 msec; P=0.020). When analyzing the delta (recovery minus rest), the RMSSD (ATP=2.1± 7.2 msec vs. placebo=-4.7±7.5 msec; P=0.009), LF (ATP=-19.8±122.7 vs. placebo=-94.1±200.2 msec2; P=0.02), and SDNN (ATP=-2.8±12.2 msec vs. placebo=-10.6±10.5 msec; P=0.010) were higher for ATP than placebo. Furthermore, there was a greater postexercise hypotension at 20 min for ATP (SBP: ATP=-13.2±8.4 mmHg vs. placebo=-6.1±9.9 mmHg; P=0.006). Acute ATP supplementation promoted greater postexercise hypotension for systolic blood pressure and induced faster recovery of heart rate variability in hypertensive women.
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OBJECTIVES: Acute post-stroke patients present cardiovascular autonomic dysfunction, which manifests as lower heart rate variability and impaired baroreflex sensitivity. However, few studies performed to date have evaluated cardiovascular autonomic function in chronic post-stroke patients. The aim of this study was to evaluate cardiovascular autonomic modulation in chronic post-ischemic stroke patients. METHODS: The seventeen enrolled subjects were divided into a stroke group (SG, n=10, 5±1 years after stroke) and a control group (CG, n=7). Non-invasive curves for blood pressure were continuously recorded (Finometer®) for 15 minutes while the subject was in a supine position. Heart rate variability and blood pressure variability were analyzed in the time and frequency domains. RESULTS: No differences were observed in systolic and diastolic pressure and heart rate between post-stroke patients and healthy individuals. The SG group had lower indexes for heart rate variability in the time domain (standard deviation of normal to normal R-R intervals, SDNN; variance of normal to normal R-R intervals, VarNN; and root mean square differences of successive R-R intervals, RMSSD) and a lower high-frequency band for heart rate variability than was observed in the CG. Systolic blood pressure variability and the low-frequency band for systolic pressure were higher in post-stroke patients, while the alpha index was lower in the SG than in the CG. CONCLUSION: After ischemic stroke, affected patients present chronically reduced heart rate variability, impaired cardiac vagal modulation, increased systolic blood pressure variability and higher sympathetic vascular modulation along with impaired baroreflex sensitivity, which can increase the risk of cardiovascular events, despite adequate blood pressure control.