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Purpose: Criterion-referenced cut-points for health-related fitness measures are lacking. This study aimed to determine the associations between aerobic fitness and high blood pressure levels (HBP) to determine the cut-points that best predict HBP among adolescents., Method: This cross-sectional school-based study with sample of 875 adolescents aged 14-19 years was conducted in southern Brazil. Aerobic fitness was assessed using the modified Canadian Aerobic Fitness Test (mCAFT). Systolic and diastolic blood pressure were measured by the oscillometric method with a digital sphygmomanometer. Analyses controlled for sociodemographic variables, physical activity, body mass and biological maturation., Results: Receiver Operating Characteristic (ROC) curves demonstrated that mCAFT measures could discriminate HBP in both sexes (female: AUC = 0.70; male: AUC = 0.63). The cut-points with the best discriminatory power for HBP were 32 mL·kg-1·min-1 for females and 40 mL·kg-1·min-1 for males. Females (OR = 8.4; 95% CI: 2.1, 33.7) and males (OR: 2.5; CI 95%: 1.2, 5.2) with low aerobic fitness levels were more likely to have HBP., Conclusion: mCAFT measures are inversely associated with BP and cut-points from ROC analyses have good discriminatory power for HBP.

The aim of this study was to identify prevalence and factors associated with violent behavior among adolescents in Aracaju and Metropolitan region. The study included 2207 adolescents (16.03±1.08 years old) enrolled in high schools of the State Public Network. Violent behavior was identified from question 14 of the YRBS-2007 questionnaire with responses categorized as "never" and "one or more times." Higher prevalence in males in relation to risk factors for adoption of violent behavior was found: cigarette consumption (7.3%), alcohol consumption (39.1%), and marijuana use (3.4%). Data analysis used descriptive statistics and logistic regression with hierarchical model at two levels: (a) sociodemographic variables and (b) behavioral variables. For both sexes, association between violent behavior and cigarette smoking (OR=3.77, CI 95%=2.06-6.92 and OR=1.99, CI 95%=1.04 to 3.81, male and female, resp.) and alcohol consumption (OR=3.38, CI 95%=2.22 to 5.16 and OR=1.83, CI 95%=1.28 to 2.63, male and female, resp.) was verified. It was concluded that violent behavior is associated with the consumption of alcoholic beverages and cigarettes among adolescents.

Background: One of the difficulties in maintaining long-term adherence to exercise is the distance from home to the place of exercise., Objective: To determine, for a private supervised exercise program (PSEP), the influence of the home-PSEP distance on adherence., Methods: We identified 976 individuals and selected 796 who met the inclusion criteria. The home-PSEP distance was obtained by the Google Maps. Adherence was determined by quartiles (months): 1-4, 5-12, 13-36 and more than 36. The clinical conditions were stratified as healthy, obese and/or hypertensive and/or dyslipidemic and/or diabetic patients without coronary disease; coronary artery disease patients and other health problems like cancer, respiratory disease and panic. The home-PSEP distance was divided into (km): up to 1, 1 to 3, 3 to 10 and more than 10. For the statistical analysis, we used the Kruskal-Wallis ANOVA and the chi-square test., Results: Of respondents, 46% lived up to 3 km, 39% lived between 3 and 10 km and about 15% lived more than 10 kilometers from the place of the PSEP. No differences were found between the medians of the months of participation in the PSEP as a function of home-PSEP distance (p = 0.11)., Conclusion: For a given PSEP in the city of Rio de Janeiro, open from Monday through Saturday with free choice of time, the home-PSEP distance did not influence the adherence of participants. This was probably due to the quality of the service and/or lack of places closer to the participants' home.

Panax ginseng C.A. Meyer, the root of an Araliaceae plant has been shown to possess various biological effects. Ginseng treatment (100 mg kg(-1)) protected muscles from eccentric exercise injuries. It was effective in preserving mitochondrial membrane integrity and reduced nitrate concentration in vastus and rectus (46% and 26%, respectively). It also reduced carbonyl contents by approximately 27% in all the muscles studied.

Enzymatic activity was analyzed in the soleus, gastrocnemius (red and white) and plantaris muscles of acutely exercised rats after long-term administration of Panax ginseng extract in order to evaluate the protective role of ginseng against skeletal muscle oxidation. Ginseng extract (3, 10, 100, or 500 mg/kg) was administered orally for three months to male Wistar rats weighing 200 +/- 50 g before exercise and to non-exercised rats (N = 8/group). The results showed a membrane stabilizing capacity of the extract since mitochondrial function measured on the basis of citrate synthase and 3-hydroxyacyl-CoA dehydrogenase activities was reduced, on average, by 20% (P < 0.05) after exercise but the activities remained unchanged in animals treated with a ginseng dose of 100 mg/kg. Glutathione status did not show significant changes after exercise or treatment. Lipid peroxidation, measured on the basis of malondialdehyde levels, was significantly higher in all muscles after exercise, and again was reduced by about 74% (P < 0.05) by the use of ginseng extract. The administration of ginseng extract was able to protect muscle from exercise-induced oxidative stress irrespective of fiber type.

Several different exercise regimens varied in the severity of tissue damage induced. Therefore, this study investigated the effects of a single bout of exercise versus endurance training in heart and skeletal muscles with different predominant fiber types on indices of mitochondrial, endoplasmic reticulum (ER) integrity and protein degradation. Male Wistar rats performed different treadmill exercise protocols: exhaustive, maximal exhaustive, eccentric, training and exhaustive exercise after training. The maximal and eccentric exercises resulted in a significant loss of integrity of the sarcoplasmic and ER muscle, while no changes were observed in cardiac muscle. Mitochondrial membrane fluidity measured by the fluorescence polarization method was significantly increased post-acute exercises in heart and oxidative muscles. Regular exercise can stabilize and preserve the viscoelastic nature of mitochondrial membranes in both tissues. The highest increase in carbonyl content was obtained in heart after exhaustive exercise protocol, from 1+/-0.1 to 3.6+/-0.14 nmol mg protein(-1), such increase were not found after regular exercise with values significantly decreased. Nitrate heart levels showed attenuated generation of nitric oxide after training. Muscle protein oxidation was produced in all exhaustive exercises including eccentric exercise.

Eccentric muscle contraction causes fibre injury associated with disruption of the myofibrillar cytoskeleton. The medicinal plant Panax ginseng C.A. Meyer, known for its therapeutic properties, was studied to explore its protective effects after eccentric contraction. A crude extract and a standardised extract (G115) of different saponin compositions were tested as to their efficacy in reducing lipid peroxidation, inflammation and release of myocellular proteins after the realisation of an eccentric contraction protocol on a rat treadmill. Plasma creatine kinase (CK) levels were significantly reduced by approximately 25% after ingestion of both extracts of ginseng. Both extracts reduced lipid peroxidation by approximately 15% as measured by malondialdehyde levels. beta-Glucuronidase concentrations and glucose-6-phosphate dehydrogenase (G6PDH) levels, which can be considered markers of inflammation, were also significantly reduced. The values of beta-glucuronidase were increased from 35.9+/-1.5 to 128.4+/-8.1 in vastus and to 131.1+/-12.1 U x g(-1) in rectus, the protection due to ginseng administration being approximately 40% in both muscles. Both extracts appeared to be equally effective in reducing injuries and inflammation caused by eccentric muscle contractions.