This study provides a relatively accurate and convenient VO2max prediction equation based on the 6MWT and body mass index in healthy boys. This model can be used for evaluation of cardiorespiratory fitness of boys in different settings.

Background: Physical activity provides extensive health benefits during adolescence; however, many adolescents do not achieve the recommended level of regular physical activity (RPA). The age-related declin in regular physical activity throughout adolescence has been documented in some studies in western countries but by our search, there has been no study in eastern countries.

BackgroundMajor cardiovascular disorders are being recognized earlier in life. In this study we examined the effects of swimming and soccer training on male adolescent lipid-lipoprotein profiles relative to a maturity matched control group to determine the effects of these exercises on specific cardiovascular risk and anti-risk factors.MethodsForty five adolescent males (11.81 ± 1.38 yr) including swimmers (SW), soccer players (SO), and non-athlete, physically active individuals as controls (C), participated in this study. Training groups completed 12-wk exercise programs on three non-consecutive days per week. Plasma low-density lipoprotein (LDL), very low density lipoprotein (VLDL), high density lipoprotein (HDL), apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), total cholesterol (TC), and triglyceride (TG) levels were measured in control, pre-training, during-training, and post-training.ResultsIn response to the 12-wk training period, the SO group demonstrated a decrease in the mean LDL level compared to the SW and C (SW: 0.15%; SO: −9.51%; C: 19.59%; p < 0.001) groups. There was an increase in both the SW and SO groups vs. the control in mean HDL (SW: 5.66%; SO: 3.07%; C: −7.21%; p < 0.05) and apoA-I (SW: 3.86%; SO: 5.48%; C: −1.01%; p < 0.05). ApoB was considerably lower in the training groups vs. control (SW: −9.52%; SO: −13.87%; C: 21.09%; p < 0.05). ApoA-I/apoB ratio was significantly higher in training groups vs. control (SW: 16.74%; SO: 23.71%; C: −17.35%; p < 0.001). There were no significant differences between groups for other factors.ConclusionsThe favorable alterations in LDL, HDL, apoA-I, and apoB observed in the training groups suggest that both regular swimming or soccer exercise can potentially mitigate cardiovascular risk in adolescent males.

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These results demonstrated that kidney and liver function impaired 14 weeks after MI and aerobic training and L-arginine supplementation synergistically ameliorated kidneys and liver injury in myocardial infarction rats through oxidative stress reduction.

Introduction: Application and correct interpretation of the 6-minute walk test (6MWT) in medical, therapeutic, and exercise settings requires normal values of the 6MWT. The aim of this study was to develop and cross-validate the 6MWT prediction equation in Iranian healthy children and adolescent males. Methods: The 6MWT and anthropometric variables were measured in 391 males (8 to 17 years old) with standard methods. Pearson correlation was used to assess the relationship between distances walked in the 6MWT and independent variables. Multiple regression analysis was used to design 6MWT prediction equation from dependent variables. Furthermore, accuracy of the present 6MWT prediction equation was crossvalidated. Results: Significant correlation was found between distances walked in the 6MWT and anthropometric characteristics (P < 0.001). Multiple stepwise regression reviled that age and Body Mass Index (BMI) could explain 63% of the variability of 6MWT in children and adolescent males (r2= 0.627, SEE= 36 m, P < 0.001). Accuracy of native 6MWT prediction equation was approved by good correlation between measured and predicted distance walked in the 6MWT (r2 = 0.79, P < 0.001). Conclusions: This is the first study on the development of native 6MWD reference values. With application of this 6MWD prediction equation, physicians, physical therapists, and fitness coaches could receive correct feedback of pharmacological, rehabilitation, and exercise interventions. How to Cite this Article: Jalili M, Nazem F. Design and Cross-Validation of Six-Minute Walk Test (6MWT) Prediction Equation in Iranian healthy Males Aged 7 to 16 Years.

Objective. It has been shown that angiogenesis is a desirable treatment for patients with ischemic heart disease. We set out to investigate the impact of high-intensity interval training (HIIT) and berberine supplementation on the gene expression of angiogenesis-related factors and caspase-3 protein in rats suffering from myocardial ischemic-reperfusion injury. Methods. Fifty rats were divided into the following groups: (1) trained, (2) berberine supplemented, (3) combined, and (4) IR. Each cohort underwent five sessions of HIIT per week for a duration of 8 weeks followed by induction of ischemia. Seven days after completion of reperfusion, changes in the gene expression of angiogenesis-related factors and caspase-3 protein were evaluated in the heart tissue. Results. We observed a significant difference between four groups in the transcript levels of vascular endothelial cell growth factor (VEGF), fibroblast growth factor-2 (FGF2), and thrombospondin-1(TSP-1) (p≤0.05). However, the difference in endostatin (ENDO) levels was not significant among the groups despite a discernible reduction (p≥0.05). Moreover, caspase-3 protein and infarct size were significantly reduced in the intervention groups (p≤0.05), and cardiac function increased in response to these interventions. Conclusion. The treatments exert their effect, likely, by reducing caspase-3 protein and increasing the expression of angiogenesis-promoting factors, concomitant with a reduction in inhibitors of the process.

The aim of the present study was to evaluate the effect of exercise training (ET) and L-arginine on oxidative stress and ventricular function in rat with myocardial infarction (MI). Four weeks after the surgical procedures, 40 Wistar male rats were randomized to the following groups: MI-sedentary (Sed); MI-exercise (Ex); MI-sedentary + L-arginine (Sed + LA); and MI-exercise + L-arginine (Ex + LA); the rats were subjected to aerobic training in the form of treadmill running. Rats in the L-arginine-treated groups drank water containing 4 % L-arginine. Before and after the training program, all subjects underwent resting echocardiography. Catalase (CAT) glutathione peroxidase (GPx), malondialdehyde (MDA) and myeloperoxidase (MPO) were measured. Cardiac output, stroke volume and fractional shortening in Ex and Ex + LA groups significantly increased in comparison with the Sed group. Cardiac systolic function indices in Ex + LA group were significantly greater than Ex group. Also, GPx activity and MDA, respectively, increased and decreased in response to ET, but no change was observed in MPO and CAT. These results suggest that ET increased LV function by decreasing oxidative stress and increasing antioxidant defense system in rats with MI. In addition in response to training, L-arginine appears to have additive effect on cardiac function, but have no effect on oxidative stress indices.