Search

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Ciência e Movimento: RBCM is the property of Revista Brasileira de Ciencia e Movimento and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article reports on the effects of physical exercise and statins on the muscular function of 80 Winstar rats with dyslipidemia. Subjects were fed with control diets (hyperchlolesterolemic and commercial) and statins (simvastatin, fluvastatin) and either with or without physical exercise. After a post-mortem histological analysis, the authors conclude that physical exercise and statins variably alter the morphology of the soleus muscle of mice.

Physical exercise and statins, which are recommended for the treatment of dyslipidemia, are independently associated to the occurrence of muscle injury. The objective is analyze the effect of aerobic exercise associated to the use of simvastatin on the morphology of the gastrocnemius muscle. Thirty Wistar rats were divided into six groups, two of which received a standard diet (1 sedentary and 1 exercised) and four (1 sedentary with medication, 1 sedentary without medication, 1 exercised with medication, 1 exercised without medication) received a hypercholesterolemic diet (standard diet with the addition of cholesterol and coconut oil). Simvastatin (20 mg/Kg) was administered five days a week for eight weeks, together with aerobic training on a treadmill (9.75 m/min) for 60 minutes a day. The gastrocnemius muscle was removed, sliced, stained with Hematoxylin-Eosin and submitted to a histochemical reaction to determine mitochondrial activity. The data were analyzed using a paired t-test, analysis of variance and Scheffé's post hoc test (p<0.05). Greater histological alterations were found in the medicated and exercised animals, with a greater frequency of occurrence as well. The histochemical analysis revealed that the medicated groups had fibers with more intensive mitochondrial activity alongside fibers with an absence of reaction. The morphometric analysis revealed no significant differences between groups. It is suggested that simvastatin is a medication that leads to the occurrence of muscle injury and its administration in association with physical activity may exacerbate these injuries. This finding may be related to cellular respiration. [ABSTRACT FROM AUTHOR]

Intermittent fasting and concurrent training have been performed frequently to decrease body mass. The aim was to analyze the effects of concurrent training (CT) and intermittent fasting (IF) on cardiac remodeling. In total, 39 adult male Wistar rats were used, divided into four groups: control (C [n = 12]), fasting control (FC [n = 11]), training (T [n = 8]) and fasting training (FT [n = 8]). The CT protocol was composed of 12 sessions, with 30 minutes of aerobic training (AT) in the liquid medium at an intensity of 80 % of the anaerobic threshold, followed by resistance training (RT) with 4 series of 10 aquatic jumps at an corresponding to 50 % of body weight. The IF period was established at 12/12 hours, starting at 9 p.m. and ending at 9 a.m. Echocardiographic analyzes were performed before and after the intervention and, at the end of the experiment, samples of the cardiac tissue were collected to perform the histological analyses. Data analysis was performed using the Shapiro-Wilk tests, Analysis of Variance - ANOVA with Tukey's post-test, and Kruskal-Wallis with Dunn's post-test. All procedures assumed an error of 5 % (p<0.05). Neither group showed alterations in the functional (min. p= 0.12 - max. p= 0.83) and structural parameters of the heart (min. p=0.31 - max. p=0.83). A decrease was observed in the area of cardiomyocytes in the T (p=0.001) and FT groups (p=0.001). The CT and IF did not alter the functional and structural parameters of the heart, but did cause a decrease in the area of the cardiomyocytes. [ABSTRACT FROM AUTHOR]

Severe muscle injuries are common in accidents and have a delayed recovery of muscle integrity. In these cases, muscle suture surgery is the standard treatment. However, Platelet Rich Plasma (PRP), has been widely used in orthopedic injuries due to its growth factors. Thus, the objective of the study will be to analyze the association of suture and PRP techniques in the collagen and tenacity of the injured muscle. Were used seventy rats, divided into five groups: control (C), injury control (CI), injury and suture (IS), injury and PRP (IP), injury, suture, and PRP (ISP). Were sectioned approximately 50 % of the width and 100 % of the thickness of the gastrocnemius muscle. The homologous PRP was applied 24h after the injury. On the 7th day after the injury, the animals were euthanized and their muscles subjected to mechanical testing to measure tenacity or collagen analysis to calculate the ratio between type I and III collagen. The results show a significant decrease (p <0.05) in the values of the relationship between collagens in all injured groups (CI, IS, IP, ISP) compared to group C. In injured groups, the tenacity was significantly (p <0.05) reduced compared to the control group, with no observed difference between treatments and injured groups. The amount of collagen in the injured area has increased, but it did not affect the tenacity of the muscles, which was reduced. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a disease triggered by environmental and genetic factors. Research suggests that physical exercise has benefits such as delaying functional disability. In vivo studies using experimental models of arthritis can provide useful information about these benefits. to analyze the effects that different intensities of aquatic physical exercise have on the proprieties of the bones in induced arthritis in knees of Wistar rats. Male Wistar adults rats (n=20) were divided into 5 groups: Group Control Arthritis (GCA) n=4, Group control Placebo (GCP) n=4, Group Low Physical Activity (GB) n=4, Group Moderate Physical Activity (GM) n=4 and Group Intense Physical Activity (GI) n=4. The physical activity groups got an intra-articular injection of Zymosam on the right knee; the GCA received saline solution in the right knee; the GCP was submitted to the stress of the needle. The animals were submitted to aquatic activity for 30 minutes, 4 times a week for 5 weeks, and the intensity of the exercise was determined by a weight placed on their back: GB=1 %, GM=5 %, GI=15 % of their body weight. It was observed that the group GB, and the groups that did not exercise GCA and GCP, gained more weight compared to the group GM. In relation to the bone mineral content of the tibia, there was a decrease in the GM group when compared to the GCP group, whereas in the tibial bone mineral density there was a decrease in the GM group compared to the GCP, GCA, GB. As for the area of the femur, the GI group presented an increase of it compared to the GB and GM groups. It is concluded that the high intensity exercises promote better results in bone properties. [ABSTRACT FROM AUTHOR]

Objective: Muscle injuries are common, and their treatment requires costs and time off. Platelet rich plasma and low level laser therapy have been shown to be affordable and easy to use. The aim of this study was to evaluate the associated effects of low level laser therapy and platelet rich plasma on the treatment of the soleus muscle injured by strain in rats. Methods: Thirty-five rats were randomly allocated into five groups: Control (C), Injury Control (IC), injury PRP (IP), injury LLLT (ILT) and injury LLLT and PRP (ILTP). The strain injury was induced in thesoleus muscle and the IP group received application of platelet rich plasma immediately after the lesion, while the ILT group received low level laser therapy. After seven days, all animals were euthanized and the soleus muscle removed for further histological analysis. Results: The association of both treatments (ILTP) resulted in better histological aspects than the low level laser therapy and platelet rich plasma alone, when compared with the injury group (IC). The collagen analysis exhibited a significant increase in the ILT group (2.99 SD = 1.13) compared to the C (1.88 SD = 0.41, p = 0.012) and IP (2.04 SD = 0.44, p = 0.018). Conclusion: The association of low level laser therapy with platelet rich plasma produced better results on muscle injury compared to the isolated use of these therapies. Furthermore, none of the treatments could modulate the collagen deposition in relation to injury group. [ABSTRACT FROM AUTHOR]

Physical effort stimulates an increase in oxygen consumption in tissues, generating toxic chemical species derived from oxygen (ROS), which are considered the initiators of the lipid peroxidation process (LPO), the major mechanism of cellular injury. As the essential mechanism for maintaining the electrolyte balance depends on an effective kidney function, oxidative stress in this organ can be a key factor in the development and persistence of hypertension. This study aimed to determine the kidney changes induced by a combination of fluid restriction and exercise in rats. The study consisted of 24 male Wistar rats of 90 days of age, divided into four groups, two of which were submitted to water restriction and exercise on a treadmill. Twenty-four hours after the last training session, the animals were euthanized and the left kidney was removed. The upper part of the kidney was used for the histological procedures and the lower part for the quantification of membrane lipoperoxides. Analysis of variance was applied after testing the normality of data, and the comparison between groups was performed using the Bonferroni test, adopting a significance of p<0.05. The restriction had an influence on body weight; kidney weight; proximal tubule maximum diameter; and area, perimeter and diameter of glomeruli, whereas the exercise affected the weight and the minimum diameter of the proximal tubule. According to the TBARS (thiobarbituric acid reactive substances) method, there was a difference between the G1 (control) and G3 (sedentary with water restriction) and between the G2 (exercised with water) and G4 (exercised with water restriction) compared to G1. The treadmill exercise combined with the water restriction promoted structural changes in the glomeruli and promoted oxidative stress, although neither variable corroborated for the potentiating of lipid peroxidation. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the effects of passive smoking, in soleus and gastrocnemius muscles associated with physical exercise by swimming during pregnancy and lactation of rats. Twenty-four rats were divided: GF (exposed to cigarette smoke), GC (control), GFN (underwent to the swimming program and exposed to cigarette smoke) and GN (underwent to the swimming program). On the first day of pregnancy procedure of exposure to cigarette smoke began, consisting in 30 minutes twice a day for six weeks. During the same period the swimming program began, which lasted 60 min every day untilthe 21st day of lactation. Soleus and gastrocnemius muscles, were obtained for histological, histochemical, morphometric analysis and fiber profiling. In histology, the groups GF and GFN showed infiltrations, necrotic and phagocytized fibers, centralized nuclei, splittings and coiling; in GN changes were observed due to exercise adaptations, infiltrations, sarcolemal lesion, polymorphic, atrophic and angular fibers. In the histochemical analysis of the groups GF and GFN there was enzymatic activity and amorphous formazan aggregates in subsarcolemmal positions, however in GN the same changes were found in lower frequency and intensity. In regard to the measure of the cross-section of muscle fibers there weren't significant differences among the groups, as well as, in the frequency of types of fibers of the gastrocnemius. It is concluded that aerobic exercise is not enough to impede morphological and histochemical changes caused in an animal model of pregnant and lactating associated with smoking, and the stress not influence the types and size of muscle fibers. [ABSTRACT FROM AUTHOR]

The objective of the present study was to analyze the effects of 14 weeks of resistance training on muscle tissue in Wistar rats. 20 male Wistar rats were used in the study; 10 allocated to the untrained group (Group 1) and 10 to the trained (Group 2). The physical training (PT) program consisted of four sets of ten water jumps, three times a week for 14 weeks. A progressive increase in load was applied from the14nd to the 42nd day. Following this, the animals were euthanized with an overdose of potassium chlorate (100 mg/ kg) applied intraperitoneally. The ventral portion of the gastrocnemius muscle was removed for histological processing. The muscles were frozen in liquid nitrogen and cut into thicknesses of 5 mm using a rotative microtome. The sections were stained with hematoxylineosin for general analysis of the structure of muscles and analysis of the area of muscle fibers. The reaction with NADH-TR was utilized for differentiation between fast twitch (FT) and slow twitch (ST) fibers. The sections subjected to staining and histochemical reactions were observed in normal and polarized light and photomicrographed using a microscope (Zeiss®). The measurement of muscle fibers was performed using AxioVision software (Zeiss®). Statistical analysis was performed using the Student t test for analysis of the samples average. An average area of 5061.29 μm2 for Group 1 versus 5768.93 μm2 for Group 2 was observed. It can be concluded that 14 weeks of training with water jumps was effective in increasing muscle area. An increase in transverse area section (TAS) of ST and FT was also verified in the trained group. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the effect of statins associated with physical exercise (PE) in liver cells in dyslipidemic rats through cariometry. The animals were divided into six groups: animals subjected to a hypercholesterolemic diet (HD), simvastatin, with (G1) and without (G2) physical exercise (PE); HD submitted (G3) or not (G4) to PE, and commercial food diet (F) with (G5) and without (G6) PE. Histological analysis of the liver was performed by staining the slides with hematoxylin and eosin. The cariometric study included measuring the major and minor diameters of the hepatocytes nuclei. The Shapiro-Wilk test was also performed. To determine the differences among the groups, the Kruskal-Wallis Test with Dunn's post-test were conducted. The significance level was set at 5%. No difference was found in the hepatocytes nuclei between G5 and G6. When these groups were related with G3 and G4, reduced nuclei were observed. There was no difference between G1 and G6. The comparison between G6 and G2 showed that the nuclei in G2 were smaller. No difference was detected between G5 and G1. Changes were observed in the nuclei shape in G2 in comparison to G1. Considering G2 and G3, a decrease in the size of nuclei was observed in G3. On the other hand, G2 showed changes in shape in the comparative analysis with G4. The size and shape of G1 nuclei were larger than G3 as well as changes in shape were observed when compared to G4. G4 showed smaller nuclei than G3. Therefore, F, associated or not with the practice of PE, does not alter the size and shape of the hepatocytes nuclei; HD combined with sedentarism influences changes in the morphometric parameters of hepatocytes; and the association of simvastatin and PE seems to protect the hepatocytes nuclei with regard to HD. [ABSTRACT FROM AUTHOR]