Erico Chagas Caperuto

MORPHOLOGICAL ADJUSTMENTS OF THE RADIAL NERVE ARE INTENSITY-DEPENDENT

Introduccion: La adaptacion de los nervios perifericos es fundamental para el aumento de fuerza. Sin embargo, la informacion sobre el efecto de la intensidad sobre la morfologia del nervio es escasa. Objetivo: Comparar el efecto de diferentes intensidades de entrenamiento de resistencia en las estructuras del nervio radial. Metodos: Las ratas se dividieron en tres grupos: control (GC) y entrenamiento con 50% (GF1) y con 75% (GF2) del peso corporal del animal. El analisis morfologico del nervio se hizo con microscopia optica y electronica de transmision. Se aplicaron la prueba ANOVA de una via y la prueba post hoc de Tukey y el nivel de significacion se fijo en p ≤ 0,05. Resultados: Los grupos de entrenamiento tuvieron aumento de la fuerza con respecto al grupo control (p ≤ 0,05). Todos los componentes medidos del nervio (area media y diametro de las fibras de mielina y axones, area media y espesor de la vaina de mielina, neurofilamentos y microtubulos) fueron mayores en GF2 en comparacion con los otros grupos (p ≤ 0,05). Conclusion: Los resultados mostraron mayores cambios morfologicos en el nervio radial despues de las cargas mas pesadas. Esto puede ser importante para terapias de rehabilitacion, entrenamiento y progresion.

Caffeine supplementation affects the immunometabolic response to concurrent training

The aim of the present study was to investigate the effects of caffeine (CAF) and carbohydrate (CHO) intake on strength performance and its metabolic and inflammatory responses during concurrent training. Seven active males ingested a double-placebo (P), CAF (capsule 5 mg/kg) or CHO (20% maltodextrin solution) supplementation before strength exercise. Participants performed three randomized sessions of 5,000-m high-intensity intermittent aerobic exercise at maximal intensity followed by strength exercise, performing after the P, CHO, and CAF intake. The blood samples were collected before (pre) and immediately after concurrent strength exercise (post). We found a similar number of repetitions and total volume in all supplementation groups. There was a main effect of time on glucose, lactate, and interleukin (IL)-6 (P<0.05). When compared the changes between groups (postvalues minus prevalues), there was lower glucose in CAF group when compared to CHO group (CAF= 5.0±10.4 vs. CHO=27.8±20 vs. P=15.1±14, P=0.031) and higher IL-6 levels (CAF=11.9±9.2 vs. CHO=−2.4±1.7 vs. P=4.3± 11.7, P=0.017). There was significant interaction for glucose and lactate (P<0.001). In conclusion, CAF and CHO intake did not improve strength performance during concurrent strength training in active males. However, CAF affected immunometabolic responses.

Reverse Cholesterol Transport: Molecular Mechanisms and the Non-medical Approach to Enhance HDL Cholesterol

Dyslipidemia (high concentrations of LDL-c and low concentrations of HDL-c) is a major cause of cardiovascular events, which are the leading cause of death in the world. On the other hand, nutrition and regular exercise can be an interesting strategy to modulate lipid profile, acting as prevention or treatment, inhibiting the risk of diseases due to its anti-inflammatory and anti-atherogenic characteristics. Additionally, the possibility of controlling different training variables, such as type, intensity and recovery interval, can be used to maximize the benefits of exercise in promoting cardiovascular health. However, the mechanisms by which exercise and nutrients act in the regulation of cholesterol and its fractions, such as reverse cholesterol transport, receptors and transcription factors involved, such as PPARs and their role related to exercise, deserve further discussion. Therefore, the objective of this review is to debate about non-medical approaches to increase HDL-c, such as nutritional and training strategies, and to discuss the central mechanisms involved in the modulation of lipid profile during exercise, as well as that can be controlled by physical trainers or sports specialists in attempt to maximize the benefits promoted by exercise. The search for papers was performed in the databases: Medline (Pubmed), Science Direct, Scopus, Sport Discus, Web of Science, Scielo and Lilacs until February 2016.

Effects of inspiratory muscle exercise in the pulmonary function, autonomic modulation, and hemodynamic variables in older women with metabolic syndrome

The aim of the present study was to investigate the effects of inspiratory muscle exercise (IME) on metabolic and hemodynamic parameters, cardiac autonomic modulation and respiratory function of older women with metabolic syndrome (MS). For this, sixteen older women with MS and 12 aged-matched controls participated of the present study. Two days before and 2 days after the main experiment, fasting blood samples (i.e., total cholesterol, triglycerides and blood glucose), cardiac autonomic modulation (i.e., heart rate variability), and respiratory muscle function were obtained and evaluated. The sessions of physical exercise was based on a IME, which was performed during 7 days. Each session of IME was performed during 20 min, at 30% of maximal static inspiratory pressure. In the results, MS group presented higher levels of triglycerides, blood glucose, and systolic blood pressure when compared to control group. IME was not able to change these variables. However, although MS group showed impaired respiratory muscle strength and function, as well as cardiac autonomic modulation, IME was able to improve these parameters. Thus, the data showed that seven days of IME are capable to improve respiratory function and cardiac autonomic modulation of older women with MS. These results indicate that IME can be a profitable therapy to counteracting the clinical markers of MS, once repeated sessions of acute IME can cause chronical alterations on respiratory function and cardiac autonomic modulation.

Impaired baroreflex sensitivity and increased systolic blood pressure variability in chronic post-ischemic stroke

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.

Multicomponent Exercise Improves Physical Functioning but Not Cognition and Hemodynamic Parameters in Elderly Osteoarthritis Patients Regardless of Hypertension

The present study aimed to investigate the impact of a 6-month multicomponent exercise program (MCEP) on physical function, cognition, and hemodynamic parameters of elderly normotensive (NTS) and hypertensive (HTS) osteoarthritis patients. A total of 99 elderly osteoarthritis patients (44 NTS and 55 HTS) were recruited and submitted to functional, cognitive, and hemodynamic evaluations before and after six months of a MCEP. The program of exercise was performed twice a week at moderate intensity. The physical exercises aggregated functional and walking exercises. Results indicate that 6 months of MCEP were able to improve one-leg stand and mobility (walking speeds) of osteoarthritis patients regardless of hypertension. On the other hand, cognitive and hemodynamic parameters were not altered after the MCEP. The findings of the present study demonstrate that 6 months of MCEP were able to improve the physical functioning (i.e., usual and maximal walking speed and balance) of osteoarthritis patients regardless of hypertensive condition.

Resistance training improves aortic structure in Wistar rats

Highlights • There is aortic adaptation to resistance training in an experimental animal model.• Resistance training promoted left ventricle concentric hypertrophy and improved aortic wall structure by increasing the density of elastic fibers and collagen fibers and increasing the thickness of collagen fibrils.• Resistance training rats displayed aortic remodeling.

Resistance training attenuates the effects of aging in the aorta of Wistar rats

The objective of the present study was to follow the structural modifications of the aortic wall in middle-aged rats submitted to a resistance training protocol for a period of four months. Three groups of 8 animals per group were considered: middle-aged group (MA), old control group (OC) and old trained group (OT). Training consisted in to climb a 1.1-m vertical (80° incline) ladder with weights tied to their tail. Aortic wall structural modifications were studied through light and electron microscopy and morphometry. The mean arterial blood pressure at rest was similar in the three experimental groups (p = .07). At the beginning of the experiment, the OC and OT groups had similar repetition maximums, ranging from 1.6-fold to 1.9-fold the body weight. At the end of the experiment, the repetition maximum of the OT group was 5-fold greater than the body weight (p = .03). The LV weight was 15% larger in the OT group than in the MA group and 12% larger than in the OC group (p = .02). The LV wall thickness of the OT group was significantly larger than that of both, the MA group and the OC group (p = .03). The LV internal diameter in the OT group was significantly smaller than that observed in the MA and OC groups (p = .02). Resistance training diminished the alterations associated with aging improving aortic wall structure by reducing the thickness, normalising the elastic material, the collagen and the smooth muscle cells. Resistance training seems to be a potential treatment for reducing the deleterious effects of aging on the aortic wall.