Biomarkers and genetic polymorphisms associated with maximal fat oxidation during physical exercise: implications for metabolic health and sports performance.

The maximal fat oxidation rate (MFO) assessed during a graded exercise test is a remarkable physiological indicator associated with metabolic flexibility, body weight loss and endurance performance. The present review considers existing biomarkers related to MFO, highlighting the validity of maximal oxygen uptake and free fatty acid availability for predicting MFO in athletes and healthy individuals. Moreover, we emphasize the role of different key enzymes and structural proteins that regulate adipose tissue lipolysis (i.e., triacylglycerol lipase, hormone sensitive lipase, perilipin 1), fatty acid trafficking (i.e., fatty acid translocase cluster of differentiation 36) and skeletal muscle oxidative capacity (i.e., citrate synthase and mitochondrial respiratory chain complexes II-V) on MFO variation. Likewise, we discuss the association of MFO with different polymorphism on the ACE, ADRB3, AR and CD36 genes, identifying prospective studies that will help to elucidate the mechanisms behind such associations. In addition, we highlight existing evidence that contradict the paradigm of a higher MFO in women due to ovarian hormones activity and highlight current gaps regarding endocrine function and MFO relationship.

Prevalence of bullying by gender and education in a city with high violence and migration in Mexico.

OBJECTIVE: To understand the prevalence of bullying, by gender and educational level, in Ciudad Juárez, Mexico, a city with high rates of violence and migration. METHODS: This was a cross-sectional, observational study conducted in 2012 - 2014 using a questionnaire known as the Bullying-Mexican. A probabilistic multistage cluster-sampling method obtained a study sample of 2 347 students (10 - 27 years of age) from the 400 000 enrolled in grade 5 - university level at the 611 public schools in Ciudad Juárez. Bullying prevalence and frequency (never, rarely, sometimes, often, every day) were analyzed with descriptive statistics. The statistical differences between males and females was assessed using a chi-square test; associations between frequency and academic level were determined by correspondence analysis and the Spearman Rho correlation. A multinomial logistic regression was performed to analyze whether gender and academic level acted independently in the frequency of bullying. RESULTS: Bullying prevalence was reported by 38% of females and 47% of males: 'only victim' represented 8.7%; 'only aggressor,' 13.2%; and 'victim and aggressor,' 21%. At higher levels of education, bullying prevalence declined; however, at the university, prevalence increased in the last semesters. Mockery and social exclusion were the two most dominant types of bullying, followed by beating, threats, and punishment. CONCLUSIONS: The prevalence of bullying in Ciudad Juárez public schools is among the highest compared to other random studies and surveys. Bullying diminishes with age and educational level.

Cardiometabolic risk in young adults from northern Mexico: Revisiting body mass index and waist-circumference as predictors.

BACKGROUND: A body mass index (BMI) ≥30 kg/m(2) and a waist circumference (WC) ≥80 cm in women (WCF) or ≥90 cm in men (WCM) are reference cardiometabolic risk markers (CMM) for Mexicans adults. However, their reliability to predict other CMM (index tests) in young Mexicans has not been studied in depth. METHODS: A cross-sectional descriptive study evaluating several anthropometric, physiological and biochemical CMM from 295 young Mexicans was performed. Sensitivity (Se), specificity (Sp) and Youden's index (J) of reference BMI/WC cutoffs toward other CMM (n = 14) were obtained and their most reliable cutoffs were further calculated at Jmax. RESULTS: Prevalence, incidence and magnitude of most CMM increased along the BMI range (p < 0.01). BMI explained 81 % of WC's variance [Se (97 %), Sp (71 %), J (68 %), Jmax (86 %), BMI = 30 kg/m(2)] and 4-50 % of other CMM. The five most prevalent (≥71 %) CMM in obese subjects were high WC, low HDL-C, and three insulin-related CMM [Fasting insulin, HOMA-IR, and QUICKI]. For a BMI = 30 kg/m(2), J ranged from 16 % (HDL-C/LDL-C) to 68 % (WC), being moderately reliable (Jmax = 61-67) to predict high uric acid (UA), metabolic syndrome (MetS) and the hypertriglyceridemic-waist phenotype (HTGW). Corrected WCM/WCF were moderate-highly reliable (Jmax = 66-90) to predict HTGW, MetS, fasting glucose and UA. Most CMM were moderate-highly predicted at 27 ± 3 kg/m(2) (CI 95 %, 25-28), 85 ± 5 cm (CI 95 %, 82-88) and 81 ± 6cm (CI 95 %, 75-87), for BMI, WCM and WCF, respectively. CONCLUSION: BMI and WC are good predictors of several CMM in the studied population, although at different cutoffs than current reference values.

Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study.

BACKGROUND: Bullying (Bull) is a public health problem worldwide, and Mexico is not exempt. However, its epidemiology and early detection in our country is limited, in part, by the lack of validated tests to ensure the respondents' anonymity. The aim of this study was to validate a self-administered test (Bull-M) for assessing Bull among high-school Mexicans. METHODS: Experts and school teachers from highly violent areas of Ciudad Juarez (Chihuahua, México), reported common Bull behaviors. Then, a 10-item test was developed based on twelve of these behaviors; the students' and peers' participation in Bull acts and in some somatic consequences in Bull victims with a 5-point Likert frequency scale. Validation criteria were: content (CV, judges); reliability [Cronbach's alpha (CA), test-retest (spearman correlation, rs)]; construct [principal component (PCA), confirmatory factor (CFA), goodness-of-fit (GF) analysis]; and convergent (Bull-M vs. Bull-S test) validity. RESULTS: Bull-M showed good reliability (CA = 0.75, rs = 0.91; p < 0.001). Two factors were identified (PCA) and confirmed (CFA): "bullying me (victim)" and "bullying others (aggressor)". GF indices were: Root mean square error of approximation (0.031), GF index (0.97), and normalized fit index (0.92). Bull-M was as good as Bull-S for measuring Bull prevalence. CONCLUSIONS: Bull-M has a good reliability and convergent validity and a bi-modal factor structure for detecting Bull victims and aggressors; however, its external validity and sensitivity should be analyzed on a wider and different population.

Association Among Different Aerobic Threshold Markers and FATmax in Men With Obesity.

Purpose: This work studies the interrelation of the first ventilatory threshold (VT1), the heart rate inflection point (HRIP), and the exercise intensity at which blood lactate started to accumulate (LIAB) or increased 1 mmol∙L-1 above baseline (LT+1.0); and examinee their association with the exercise intensity eliciting maximal fat oxidation (FATmax). Methods: Eighteen young men with obesity performed an incremental-load exercise test on a treadmill after overnight fasting. Gas exchange, heart rate, and blood lactate concentration were recorded. Linear regression analysis was used to determine the association among FATmax and AeT markers. A standard error of estimate (SEE) ≤9 beats∙min-1 and the concordance correlation coefficient (CCC) were used to examine the accuracy of different AeT for predicting FATmax heart rate. Results: The FATmax occurred at 36±7%VO2peak before the HRIP (41±6%VO2peak), LIAB (42±10%VO2peak), LT+1.0 (61±9%VO2peak) and VT1 (40±7%VO2peak). Furthermore, the HRIP (R2= 0.71; SEE= 6 beats∙min-1; CCC=0.77), VT1 (R2= 0.76; SEE= 5 beats∙min-1; CCC=0.84) and LIAB (R2= 0.77; SEE= 5 beats∙min-1; CCC=0.85) were strongly associated to FATmax and showed an acceptable estimation error for predicting FATmax heart rate. Otherwise, LT+1.0 showed a moderate correlation with FATmax, a low accuracy for predicting FATmax HR (R2= 0.57; SEE= 7 beats∙min-1; CCC=0.66) and a poor agreement with the rest of AeT markers (Bias: +20%VO2peak). Conclusion: The HRIP, LIAB and VT1 did not perfectly captured the FATmax, however, these could be exchanged for predicting the FATmax heart rate in men with obesity. Moreover, the LT+1.0 should not be used for AeT or FATmax assessment in men with obesity.

Anthropometric Equations to Determine Maximum Height in Adults ≥ 60 Years: A Systematic Review.

Although it is common to measure bone lengths for study, methodological errors in data measurement and processing often invalidate their clinical and scientific usefulness. This manuscript reviews the validity of several published equations used to determine the maximum height in older adults, since height is an anthropometric parameter widely employed in health sciences. A systematic review of original articles published in the English, Spanish, or Portuguese languages was performed in PubMed, ScienceDirect, EBSCO, Springer Link, and two institutional publisher integrators (UACJ and CONRICYT). The search terms were included in the metasearch engines in a combined way and text form using the Boolean connectors AND and OR {(Determination OR Estimation OR Equation) AND Height AND (Elderly OR "Older adults")}. Eleven manuscripts were selected from 1935 records identified through database searching after applying the following criteria: (1) original articles that designed and validated equations for the determination of height by anthropometric methods in adults 60 years of age and older and (2) manuscripts that presented robust evidence of validation of the proposed regression models. The validity of the reported linear regression models was assessed throughout a manuscript review process called multi-objective optimization that considered the collection of the models, the prediction errors, and the adjustment values (i.e., R2, standard error of estimation, and pure error). A total of 64 equations were designed and validated in 45,449 participants (57.1% women) from four continents: America (85.3%, with 46 equations), Asia (8.1%, with 10), Europe (4.6%, with 7), and Africa (2.0%, with 1); the Hispanic American ethnic group was the most numerous in participants and equations (69.0%, with 28). Due to various omissions and methodological errors, this study did not find any valid and reliable equations to assess the maximum height in older adults by anthropometric methods. It is proposed to adjust allometric mathematical models that can be interpreted in the light of ontogenetic processes.

Exercise Fat Oxidation Is Positively Associated with Body Fatness in Men with Obesity: Defying the Metabolic Flexibility Paradigm.

Obesity is thought to be associated with a reduced capacity to increase fat oxidation in response to physical exercise; however, scientific evidence supporting this paradigm remains scarce. This study aimed to determine the interrelationship of different submaximal exercise metabolic flexibility (Metflex) markers and define its association with body fatness on subjects with obesity. Twenty-one male subjects with obesity performed a graded-intensity exercise protocol (Test 1) during which cardiorespiratory fitness (CRF), maximal fat oxidation (MFO) and its corresponding exercise intensity (FATmax) were recorded. A week afterward, each subject performed a 60-min walk (treadmill) at FATmax (Test 2), and the resulting fat oxidation area under the curve (TFO) and maximum respiratory exchange ratio (RERpeak) were recorded. Blood lactate (LAb) levels was measured during both exercise protocols. Linear regression analysis was used to study the interrelationship of exercise Metflex markers. Pearson's correlation was used to evaluate all possible linear relationships between Metflex and anthropometric measurement, controlling for CRF). The MFO explained 38% and 46% of RERpeak and TFO's associated variance (p < 0.01) while TFO and RERpeak were inversely related (R2 = 0.54, p < 0.01). Body fatness positively correlated with MFO (r = 0.64, p < 0.01) and TFO (r = 0.63, p < 0.01) but inversely related with RERpeak (r = -0.67, p < 0.01). This study shows that MFO and RERpeak are valid indicators of TFO during steady-state exercise at FATmax. The fat oxidation capacity is directly associated with body fatness in males with obesity.

Body Image Satisfaction as a Physical Activity Indicator in University Students.

OBJECTIVE: We examined the association of body image satisfaction (BIS) with physical activity (PA) in university athletes and non-athletes from northern Mexico. METHODS: In a non-probability cross-sectional study, 294 participants (51% male, 41% athletes; 18-35 years old) completed 2 self-administered questionnaires to evaluate BIS and PA. We categorized somatotypes (endomorphy-mesomorphy-ectomorphy) by international standardized anthropometry. Data analysis included the Mann-Whitney U test, χ2test, Kendall's Tau-b correlation, binary logistic regression analysis, and receiver operating characteristic (ROC) curves. RESULTS: Self-perceived sports abilities and desirable body shape predicted 30% of sports participation in students, whereas an endomorphic shape (<5.4 units) and being male predicted 15.4% of sports participation. CONCLUSIONS: BIS was a reliable indicator of sports participation among these university students.

Transient cardiac dysfunction but elevated cardiac and kidney biomarkers 24 h following an ultra-distance running event in Mexican Tarahumara.

BACKGROUND: The Mexican Tarahumara are accustomed to running ultra-distance races. No data exist on the acute physiological changes following ultra-distance running and physiological-biomarker associations in this population. Thus, we aimed to investigate the acute impact (≤ 24 h) on functional and biochemical changes of the cardiac muscle and biochemical changes associated with kidney function following a 63-km ultra-distance race with an altitude difference of 1800 m in Mexican Tarahumara athletes. METHODS: Ten Tarahumara male athletes (mean ± SD age = 29.9 ± 6.6 years) volunteered to participate in the study. VO2max was assessed by a sub-maximal step test individually calibrated combining heart rate and accelerometry. Standard transthoracic echocardiography methodology and venipuncture blood tests were carried out at four time points: pre-race, immediately post-race, 6 h, and 24 h post-race. RESULTS: Estimated mean VO2max was 54.5 (± 8.8) mL O2 min-1 kg-1 and average physiological activity intensity was 746 (± 143) J min-1 kg -1 (~ 11.5 METs). When compared to pre-race values, significant changes in left ventricular ejection fraction (LVEF) and LV end-diastolic volume (- 15%, p < 0.001 for both parameters), cardiac output (39%, p < 0.001), and maximal longitudinal velocity (- 13%, p < 0.009) were seen post-race with LVEF also being decreased at < 6 h post-race (- 8%, p < 0.014). Plasma biomarkers mid-regional pro-atrial natriuretic peptide, copeptin-ultra sensitive, and high-sensitivity cardiac troponin T remained significantly elevated at 24 h post-race, and the two latter were inversely associated with LVEF (p < 0.04). Kidney dysfunction was indicated by increased post-race copeptin-ultra sensitive. CONCLUSIONS: The athletes participating in this study had acute transient cardiac dysfunction as assessed by echocardiography but elevated cardiac and kidney biomarkers at 24 h following a 63-km race with extreme altitude variation.

Body shape as body image determinant in university students.

INTRODUCTION AND OBJECTIVES: Body shape (BSP) and body image (BI) are part of the external physical structure, then modifications in body shape necessarily affect body image; however, both combined have not been studied. The purpose of the study was to evaluate the statistical relationship between BSP and BI in university students. METHOD: Two hundred and ninety-six participants (17-35 years) were included in this study. Different anthropometric measurements were used to define their somatotype (BSP), body mass index (BMI), waist to hip ratio (WHR) and waist circumference (WC). In addition, a questionnaire on body image perception was applied (McElhone et al.), regarding "how do I look?", "how do I think others see me?", "how do others see me?", and "how do I want to look like?". RESULTS: On average, men perceived themselves in normal weight; in contrast, women perceived themselves as overweight. Men were meso-endomorphic, while women were endo-mesomorphic as an average. CONCLUSION: Body shape measured as somatotype as well as WC and WHR were excellent determinants of body image. Participants who presented a higher endomorphy, WC and WHR and a lower ectomorphy had a higher appreciation of being overweight or obese and wish to become thinner.

Yoga, bioenergetics and eating behaviors: A conceptual review.

Yoga is an ancient oriental discipline that emerged from mystical and philosophical concepts. Today it is practiced in the west, partly due to the promotion of its benefits to improve the lifestyle and overall health. As compared to non-Hatha Yoga (HY) practitioners, healthier and better-eating patterns have been observed in those who practice it. Agreement with the brought benefits, HY can be used as a therapeutic method to correct abnormal eating behaviors (AEB), obesity, and some metabolic diseases. However, the energy expenditure during traditional protocols of HY is not high; hence, it is not very effective for reducing or maintaining body weight or to improve cardiovascular conditioning. Even so, several observational studies suggest significant changes in eating behaviors, like a reduction in dietary fat intake and increments in that of fresh vegetables, whole grains and soy-based products, which in turn may reduce the risk for cardiovascular diseases. Given the inconsistency of the results derived from cross-sectional studies, more case-control studies are needed to demonstrate the efficacy of HY as an alternative method in the clinical treatment of disordered eating and metabolic diseases.

[SPIRULINA AND ITS HYPOLIPIDEMIC AND ANTIOXIDANT EFFECTS IN HUMANS: A SYSTEMATIC REVIEW]. / SPIRULINA Y SU EFECTO HIPOLIPEMIANTE Y ANTIOXIDANTE EN HUMANOS: UNA REVISIÓN SISTEMÁTICA.

Several chronic transmissible (e.g. AIDS) and non transmissible diseases like cadiovascular disease, are associated with oxidative stress (EOX) and dyslipidemia. Has been reported that Spirulina can reduce them, this has been demonstrated in vitro and in animal models but scarcely in humans. Through a systematic review on last 5 years (keywords: Spirulina AND cholesterol, Spirulina AND oxidative stress) 8 intervention studies with humans were reported, finding that oral (1-10 g/d) subchronic (0.5-6 month) administration of Spirulina appears to have and hypolipidemic and antioxidant effect. However, no study was properly randomized and/or controlled and no biological mechanism was proposed to support these findings. The level of evidence and the absence of appropriate experimental designs do not allow validating Spirulina as a functional food for preventing dyslipidemic diseases and EOX, and hereby decrease the CVD. We do not found papers relating harmful effect.

Varias enfermedades crónicas transmisibles (p. ej. SIDA) y no transmisibles, entre ellas las enfermedades cardiovasculares (ECV), cursan con estrés oxidativo (EOX) y dislipidemia. Según estudios in vitro en animales y algunos en humanos, la Spirulina puede reducir esta patología. Mediante una revisión sistemática de los últimos cinco años (palabras clave: Spirulina AND cholesterol, Spirulina AND oxidative stress) se localizaron ocho estudios de intervención en humanos, encontrándose que la administración (1-10 g/d) subcrónica (0,5-6 meses) parece tener efecto hipolipemiante y antioxidante. Sin embargo, ningún estudio fue correctamente aleatorizado y/o controlado, y tampoco se proponen los mecanismos biológicos que respalden estos efectos. El nivel de evidencia encontrado y la ausencia de diseños experimentales apropiados no permiten comprobar el valor de la Spirulina como alimento funcional para prevenir la dislipidemia y el EOX y, por este medio, disminuir las ECV; sin embargo, no encontramos manuscritos que refieran efectos nocivos de su ingesta.

Ecuaciones antropométricas para el cálculo de grasa corporal en adultos jóvenes / Anthropometric equations for calculating body fat in young adults

Dado que para la población Latinoamericana se cuenta con escasas ecuaciones antropométricas validadas para determinar porcentaje de masa grasa (% MG), se diseñaron ecuaciones antropométricas prácticas para calcular el % MG en adultos jóvenes. Se realizaron mediciones antropométricas por técnicas validadas, y se calculó el % MG por densitometría (BodPod) y biompedancia. Se reclutaron 284 voluntarios (18-35 años), de uno y otro sexo. Las ecuaciones se diseñaron por regresión lineal múltiple por el método de todas las regresiones posibles y se validaron por su grado de bondad de ajuste (R2), error estándar de estimación (EEE) y por validación cruzada. En hombres: % MG por densitométría R2 = 0.78, EEE = 3.64 %, p < 0.001; % MG por bioimpedancia R2 = 0.76, EEE = 2.48 %, p < 0.001. En mujeres: % MG por densitométría R2 = 0.98, EEE = 4.02%, p < 0.001; % MG por bioimpedancia R2= 0.99, EEE = 2.37 %, p < 0.001. Las ecuaciones aquí diseñadas presentan sencillez, alta validez y confiabilidad, siendo útiles en la clínica y campo deportivo(AU)

Given that in Latin America we have few validated anthropometric equations to determine percentage of fat mass (% MG), practical anthropometric equations were designed to calculate the % MG in young adults. Anthropometric measurements were made by validated techniques, and % MG was calculated by densitometry (BodPod) and bioimpedance. We recruited 284 volunteers (18-35 years), men and women. The equations were designed by multiple linear regression by the method of all possible regressions, and validated by their degree of goodness of fit (R2), standard error of estimation (SES), and cross-validation. In men: % MG by densitometry R2 = 0.78, SES = 3.64%, p <0.001; % MG by bioimpedance R2 = 0.76, SES = 2.48%, p <0.001. In women: % MG by densitometry R2 = 0.98, SES = 4.02 %, p <0.001; % MG by bioimpedance R2 = 0.99, SES = 2.37 %, p <0.001. The equations here designed have simplicity, high validity, and reliability, being useful in the clinic and sports field(AU)

Prevalence of bullying by gender and education in a city with high violence and migration in Mexico / Prevalencia de intimidación desglosada en función del sexo y la escolaridad en una ciudad mexicana con índices altos de violencia y migración / Prevalência de bullying por gênero e escolaridade em uma cidade com altos índices de violência e migração no México

ABSTRACT Objective To understand the prevalence of bullying, by gender and educational level, in Ciudad Juárez, Mexico, a city with high rates of violence and migration. Methods This was a cross-sectional, observational study conducted in 2012 – 2014 using a questionnaire known as the Bullying-Mexican. A probabilistic multistage cluster-sampling method obtained a study sample of 2 347 students (10 – 27 years of age) from the 400 000 enrolled in grade 5 – university level at the 611 public schools in Ciudad Juárez. Bullying prevalence and frequency (never, rarely, sometimes, often, every day) were analyzed with descriptive statistics. The statistical differences between males and females was assessed using a chi-square test; associations between frequency and academic level were determined by correspondence analysis and the Spearman Rho correlation. A multinomial logistic regression was performed to analyze whether gender and academic level acted independently in the frequency of bullying. Results Bullying prevalence was reported by 38% of females and 47% of males: ‘only victim’ represented 8.7%; ‘only aggressor,’ 13.2%; and ‘victim and aggressor,’ 21%. At higher levels of education, bullying prevalence declined; however, at the university, prevalence increased in the last semesters. Mockery and social exclusion were the two most dominant types of bullying, followed by beating, threats, and punishment. Conclusions The prevalence of bullying in Ciudad Juárez public schools is among the highest compared to other random studies and surveys. Bullying diminishes with age and educational level.

RESUMEN Objetivo Comprender la prevalencia de intimidación o bullying, desglosada en función del sexo y el nivel de escolaridad, en Ciudad Juárez (México), ciudad con índices altos de violencia y migración. Métodos Este estudio transversal de observación se realizó entre el 2012 y el 2014 con el cuestionario mexicano sobre la intimidación (Bull-M). Tras aplicar el método probabilístico polietápico de muestreo por conglomerados, se obtuvo una muestra de 2 347 estudiantes (de 10 a 27 años) de los 400 000 matriculados entre el quinto grado y el nivel universitario en las 611 instituciones de educación pública de Ciudad Juárez. Se analizaron la prevalencia y la frecuencia de la intimidación (nunca, rara vez, a veces, a menudo, todos los días) mediante estadísticas descriptivas. Se evaluó la diferencia estadística entre los hombres y las mujeres con la prueba de la ji al cuadrado y se determinó la asociación entre la frecuencia y el nivel académico mediante el análisis de correspondencias y la correlación ro de Spearman (R). Se aplicó una regresión logística polinómica para analizar si el sexo y el nivel académico eran variables independientes respecto de la frecuencia de la intimidación. Resultados La intimidación tuvo una prevalencia del 38% en las mujeres y del 47% en los hombres: refirieron ser “solo víctimas” el 8,7%; “solo agresores” el 13,2%; y “víctimas y agresores” el 21%. La prevalencia de la intimidación disminuye a medida que aumenta el nivel de escolaridad, aunque se registró un incremento en los últimos semestres de la universidad. Los dos tipos más predominantes de intimidación son la burla y la exclusión social, a los que siguen la agresión física, la amenaza y el castigo. Conclusiones La prevalencia de intimidación en las instituciones de educación pública de Ciudad Juárez se encuentra entre las más altas cuando se la compara con otros estudios y encuestas de diseño aleatorizado. La intimidación disminuye a medida que avanza la edad y aumenta el nivel de escolaridad.

RESUMO Objetivo Compreender a prevalência de bullying, estratificada por gênero e escolaridade, em Ciudad Juárez, México, um município com altos índices de violência e migração. Métodos Estudo transversal observacional realizado em 2012-2014 usando o instrumento Bullying-Mexican. Utilizando um método probabilístico de amostragem multietápica por conglomerados, obteve-se uma amostra de 2 347 estudantes (10-27 anos de idade) do universo de 400 000 estudantes matriculados da 5ª série ao ensino superior nas 611 escolas públicas de Ciudad Juárez. A prevalência e frequência (nunca, raramente, às vezes, frequentemente, todos os dias) de bullying foram analisadas mediante estatísticas descritivas. A diferença estatística entre homens e mulheres foi avaliada através do teste qui-quadrado; associações entre frequência de bullying e escolaridade foram determinadas mediante análise de correspondência e coeficiente de correlação de Spearman (R). Foi realizada análise de regressão logística multinomial para determinar se gênero e escolaridade influenciaram independentemente a frequência de bullying. Resultados O bullying foi relatado por 38% das mulheres e 47% dos homens: 8,7% identificaram-se como “somente vítimas”, 13,2% como “somente agressor”, e 21% como “vítima e agressor”. Nos níveis mais altos de escolaridade, a prevalência de bullying foi menor; porém, no ensino superior, aumentou novamente nos últimos semestres. Assédio verbal e exclusão social foram os dois tipos mais comuns de bullying, seguidos de agressão física, ameaças e castigos. Conclusões A prevalência de bullying nas escolas públicas de Ciudad Juárez está entre as mais elevadas já relatadas em estudos randomizados e levantamentos. O bullying diminui conforme a idade e escolaridade aumentam.

Cardiovascular and metabolic effects of intensive Hatha Yoga training in middle-aged and older women from northern Mexico.

BACKGROUND: Hatha Yoga (HY) can be an alternative to improve physical activity in middle-aged and older women. However, conventional HY (CHY) exercising may not result in enough training stimulus to improve cardiovascular fitness. The purpose of this study was to evaluate the effect of an intensive HY intervention (IHY) on cardiovascular risk factors in middle-aged and older women from Northern Mexico. MATERIALS AND METHODS: In this prospective quasiexperimental design, four middle-aged and nine older CHY practicing females (yoginis) were enrolled into an 11-week IHY program consisting of 5 sessions/week for 90 min (55 sessions). The program adherence, asana performance, and work intensity were assessed along the intervention. Anthropometric [body mass index (BMI), % body fat and Σ skin folds], cardiovascular fitness [maximal expired air volume (VE(max)), maximal O(2) consumption (VO(2max)), maximal heart rate (HR(max)), systolic (BPs) and diastolic blood pressure (BPd)], biochemical [glucose, triacylglycerols (TAG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)], and dietary parameters were evaluated before and after IHY. RESULTS: Daily caloric intake (~1,916 kcal/day), program adherence (~85%), and exercising skills (asana performance) were similar in both middle-aged and older women. The IHY program did not modify any anthropometric measurements. However, it increased VO(2max) and VE(max) and HDL-C while TAG and LDL-C remained stable in both middle-aged and older groups (P < 0.01). CONCLUSIONS: The proposed IHY program improves different cardiovascular risk factors (namely VO(2max) and HDL-C) in middle-aged and older women.

The Respiratory Exchange Ratio is Associated with Fitness Indicators Both in Trained and Untrained Men: A Possible Application for People with Reduced Exercise Tolerance.

BACKGROUND: The respiratory exchange ratio (RER) indirectly shows the muscle's oxidative capacity to get energy. Sedentarism, exercise and physically active lifestyles modify it. For that reason, this study evaluates the associations between RER during sub-maximum exercise and other well established fitness indicators (body fat, maximum heart rate, maximum O(2) uptake, workload, and lactate threshold), in physically active trained and untrained men. METHODS: The RER, O(2) uptake and blood lactate were measured in eight endurance trained and eight untrained men (age, 22.9 ± 4.5 vs. 21.9 ± 2.8 years; body mass, 67.1 ± 5.4 vs. 72.2 ± 7.7 kg; body fat, 10.6 ± 2.4% vs. 16.6 ± 3.8% and maximum O(2) uptake, 68.9 ± 6.3 vs. 51.6 ± 5.8 ml•kg(-1)•min(-1)), during maximum exercise test and during three different sub-maximum exercises at fixed workload: below, within or above the lactate threshold. RESULTS: Endurance trained men presented higher O(2) uptake, lower blood lactate concentrations and lower RER values than those in untrained men at the three similar relative workloads. Even though with these differences in RER, a strong association (p < 0.05) of RER during sub-maximum exercise with the other well established fitness indicators was observed, and both maximum O(2) uptake and lactate threshold determined more than 57% of its variance (p < 0.05). CONCLUSIONS: These data demonstrate that RER measurement under sub-maximum exercise conditions was well correlated with other established physical fitness indicators, despite training condition. Furthermore, the results suggest that RER could help obtain an easy approach of fitness status under low exercise intensity and could be utilized in subjects with reduced exercise tolerance.