Alejandra D. Benítez-Arciniega

The effect of exercise on cardiovascular risk markers in Mexican school-aged children: comparison between two structured group routines

OBJECTIVE To assess the effects of two groups of exercise routines on cardiovascular disease risk markers. MATERIAL AND METHODS An intervention study was conducted with 319 Mexican school-aged children in which routines were implemented Monday through Friday for 12 weeks. Routine A was the reference group, with 20 min of less intense activity and routine B was the new group with 40 min of aerobic exercises. Body mass index (BMI), waist circumference, fat mass percentage (FM%), systolic and diastolic blood pressure, lipids, lipoproteins, glucose and insulin were measured before and after the intervention. RESULTS Routine A had an effect on diastolic pressure, while routine B had an effect on BMI, FM%, blood pressure and triglycerides. Routine B had a greater effect on blood pressure than routine A. The prevalence of obesity, high blood pressure and hypertriglyceridemia decreased in both groups. CONCLUSION Aerobic exercise is an effective health promotion strategy to reduce some cardiovascular disease risk markers.

Are immunoglobulin concentrations associated with the body composition of adolescents

The aim of this study was to analyze the association between serum concentrations of immunoglobulins (Ig) A, G, and M and body composition of adolescents from Mexico. Informed consent was obtained from parents and assent was obtained from the adolescents for the evaluation of 125 adolescents from the Capital city of Toluca and the adjacent semiurban county of Lerma de Villada. Height, weight, waist, and hip circumference were measured by trained personnel. Body mass index and waist:hip ratio were calculated from these measurements, whereas body fat (BF) was calculated from tricipital and subscapular skinfolds and measured by bioelectrical impedance. Serum concentrations of Ig were determined by nephelometry. Data were analyzed by independent samples t test and Pearson correlations. Subjects were mainly females (71.2%), with a mean age of 16.8 years (+/-0.8). No differences were reported in all indicators by weight or BF between gender. Female participants had higher Ig concentrations than males (IgG t = 2.24, p = 0.027; IgA t = 2.05, p = 0.043; IgM t = 4.49, p < 0.001). Positive correlations were reported for IgA and IgM with tricipital skinfold (r = 0.192, p = 0.041; and r = 0.221, p = 0.018, respectively) and for total BF by bioimpedance (r = 0.243, p = 0.009). Ig concentrations do not seem to be affected by overweight, obesity, or excessive or central BF in adolescents.

Association Between Cardiovascular Risk Factors and Stress Hormones With Cognitive Performance in Mexican Adolescents

Objective The objective of this study was to determine whether cardiovascular disease (CVD) risk factors and stress hormones are associated with cognitive performance in Mexican adolescents. Methods This was a cross-sectional study including 139 Mexican adolescents 10-14 years old. Participants were divided into three categories: 0, 1-2, and ≥3 CVD risk factors. These factors included: high-density lipoprotein-cholesterol (HDL-C) <40 mg/dl; waist circumference (WC) ≥90th percentile for age and sex, systolic or diastolic blood pressure ≥90th percentile for age, sex, and height; and triacylglycerols (TGs) ≥110 mg/dl. Low-density lipoprotein-cholesterol (LDL-C), very low-density lipoprotein-cholesterol (VLDL-C), total cholesterol, cortisol, and plasma catecholamines were measured as well. Furthermore, attention, memory, and executive functions were evaluated using a validated test for Spanish-speaking individuals (Neuropsi). Results Adolescents in the three risk categories did not show significant differences in Neuropsi test performance tasks; however, they presented different lipid and plasma norepinephrine concentrations. TG and VLDL-C were inversely associated with memory (r = -0.19, **p < .01). Multivariate regression analysis showed consistently that TG/HDL-C ratio was inversely related to attention-memory general score (standardized β = -0.99, t = -2.30, p = .023), memory (standardized β = -0.83, t = -2.08, p = .039), and attention-executive functions (standardized β = -1.02, t = -2.42, p = .017). Plasma epinephrine levels presented an inverse and weak relation to the attention-executive functions score (standardized β = -0.18, t = -2.19, p = .030). Conclusions Cognitive performance is not completely dependent on the accumulation of risk factors, but instead on the combination of strong predictors of CVD like waist to height ratio, TG/HDL-C, and VLDL-C. Plasma norepinephrine and epinephrine have a stronger association with cognition and CVD risk than dopamine and cortisol.