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Introduction: Pulmonary arterial stenosis (PAS) is a congenital defect that causes outflow tract obstruction of the right ventricle (RV). Currently, negative issues are reported in the PAS management: not all patients may be eligible to surgeries; there is often the need for another surgery during passage to adulthood; patients with mild stenosis may have later cardiac adverse repercussions. Thus, the search for approaches to counteract the long-term PAS effects showed to be a current target. At the study herein, we evaluated the cardioprotective role of exercise training in rats submitted to PAS for 9 weeks. Methods and Results: Exercise resulted in improved physical fitness and systolic RV function. Exercise also blunted concentric cavity changes, diastolic dysfunction, and fibrosis induced by PAS. Exercise additional benefits were also reported in a pro-survival signal, in which there were increased Akt1 activity and normalized myocardial apoptosis. These findings were accompanied by microRNA-1 downregulation and microRNA-21 upregulation. Moreover, exercise was associated with a higher myocardial abundance of the sarcomeric protein α-MHC and proteins that modulate calcium handling-ryanodine receptor and Serca 2, supporting the potential role of exercise in improving myocardial performance. Conclusion: Our results represent the first demonstration that exercise can attenuate the RV remodeling in an experimental PAS. The cardioprotective effects were associated with positive modulation of RV function, survival signaling pathway, apoptosis, and proteins involved in the regulation of myocardial contractility.

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BACKGROUND: Studies on the relationship between physical activity (PA) and being overweight/obese are inconclusive. OBJECTIVE: The purpose of this study was to examine the prevalence of excess body weight (EBW) and its association with daily PA level in a sample of 1506 Brazilian teachers. METHODS: The PA level was analyzed with the International Physical Activity Questionnaire and EBW was categorized as a body mass index (BMI) ≥25 kg/m2 and called 'overweight'. Chi-squared test and odds ratios (OR) were applied in the analysis. RESULTS: The prevalence of persons who were overweight was lower as a function of higher PA levels and higher PA levels resulted in a lower prevalence of overweight for men and women, respectively. The authors found that for men, moderate (OR: 1.69; P = 0.03) and high (OR: 2.57; P = 0.002) PA levels were predictive for being in the normal body mass index (BMI) range. In women, a greater association of being in the normal BMI range was reported only for a moderate PA level (OR: 1.43; P = 0.004). CONCLUSIONS: Higher daily PA levels are associated with being in the normal BMI range. To date, these findings will have important public health implications for an effective plan for the prevention of weight gain in Brazilian teachers.

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This study examined whether passive static stretching reduces the maximum muscle strength achieved by different body segments in untrained and resistance-trained subjects. Twenty adult men were assigned to 1 of the following groups: untrained (UT, N = 9) and resistance-trained (RT, N = 11) groups. The subjects performed six 1 repetition maximum (1RM) load tests of the following exercises: horizontal bench press, lat pull-downs, bicep curls, and 45° leg press. The results achieved in the last two 1RM tests were used for statistical analyses. A passive static stretching program was incorporated before the sixth 1RM test. The body fat content was significantly higher in the UT group compared with the RT group (p < 0.0001). Moreover, the RT group showed significantly higher proportion of lean body mass compared with the UT group (p < 0.0001). Maximum muscle strength on all 4 exercises was significantly reduced in both groups after stretching (p < 0.01). Furthermore, the magnitude of muscle strength reduction was similar for the UT and the RT groups. The exception was for barbell curls, in which the muscle strength depression was significantly higher in the UT group compared with the RT group (p < 0.0001). In conclusion, the passive static stretching program was detrimental to upper- and lower-body maximal muscle strength performance in several body segments. The negative effects of stretching were similar for subjects participating in resistance training regimens.

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