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PURPOSE: To examine the association of the single nucleotide polymorphism A1470T in the SLC16A1 gene with blood lactate accumulation during a graded exercise test and its associated metaboreflex. METHODS: Forty-six Latin-American men (Age: 27 ± 6 years; Body fat: 17.5 ± 4.7%) performed a graded exercise test on a treadmill for the assessment of maximal oxygen uptake (VO2max), lactate threshold (LT), ventilatory threshold (VT) and the exercise intensity corresponding to maximal fat oxidation rate (FATmax), via capillary blood samples and indirect calorimetry. Genomic DNA was extracted from a peripheral blood sample. Genotyping assay was carried out by real-time polymerase chain reaction to identify the A1470T polymorphism (rs1049434). RESULTS: Genotypes distribution were in Hardy-Weinberg equilibrium (X2 = 5.6, p > 0.05), observing allele frequencies of 0.47 and 0.53 for the A and T alleles, respectively. No difference in VO2max, body composition nor FATmax were observed across genotypes, whereas carriers of the TT genotype showed a higher LT (24.5 ± 2.2 vs. 15.6 ± 1.7 mL kg-1 min-1, p < 0.01) and VT in comparison to carriers of the AA + AT genotypes (32.5 ± 3.3 vs. 21.7 ± 1.5 mL kg-1 min-1, p < 0.01). Both, VO2max and the A1470T polymorphism were positively associated to the LT (R2 = 0.50, p < 0.01) and VT (R2 = 0.55, p < 0.01). Only VO2max was associated to FATmax (R2 = 0.39, p < 0.01). CONCLUSION: Independently of cardiorespiratory fitness, the A1470T polymorphism is associated to blood lactate accumulation and its associated ventilatory response during submaximal intensity exercise. However, the A1470 polymorphism does not influence fat oxidation capacity during exercise in young men.
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Ácido Láctico , Transportadores de Ácidos Monocarboxílicos , Polimorfismo de Nucleotídeo Único , Simportadores , Humanos , Masculino , Adulto , Ácido Láctico/sangue , Simportadores/genética , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Consumo de Oxigênio/genética , Consumo de Oxigênio/fisiologia , Oxirredução , Teste de Esforço , Genótipo , Limiar Anaeróbio/genética , Limiar Anaeróbio/fisiologia , Exercício Físico/fisiologia , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologiaRESUMO
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.
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Desempenho Atlético , Consumo de Oxigênio , Tecido Adiposo/metabolismo , Biomarcadores/metabolismo , Exercício Físico/fisiologia , Ácidos Graxos não Esterificados , Feminino , Humanos , Oxirredução , Consumo de Oxigênio/fisiologia , Polimorfismo Genético , Estudos Prospectivos , Receptores Adrenérgicos beta 3/metabolismoRESUMO
Low-fat diets, lipid-modifying nutraceuticals and a higher level of physical activity are often recommended to reduce dyslipidemia. A double-blind, randomized, crossover, controlled trial was designed to evaluate the independent and synergistic effects of Arthrospira (Spirulina) maxima supplementation (4.5 g·day-1) with or without performing a physical exercise program (PEP: aerobic exercise (3 days·week-1) + high-intensity interval training (2 days·week-1)) on blood lipids and BMI of 52 sedentary men with excess body weight. During six weeks, all participants were assigned to four intervention treatments (Spirulina maxima with PEP (SE), placebo with PEP (Ex), Spirulina maxima without PEP (Sm), placebo without PEP (C; control)) and plasma lipids were evaluated spectrophotometrically pre- vs. post intervention in stratified subgroups (overweight, obese and dyslipidemic subjects). Pre/post comparisons showed significant reductions in all plasma lipids in the SE group, particularly in those with dyslipidemia (p ≤ 0.043). Comparing the final vs. the initial values, BMI, total cholesterol, triglycerides and low-density lipoprotein cholesterol were decreased. High-density lipoprotein cholesterol increased in all treatment groups compared to C. Changes were observed mostly in SE interventions, particularly in dyslipidemic subjects (p < 0.05). Spirulina maxima supplementation enhances the hypolipidemic effect of a systematic PEP in men with excess body weight and dyslipidemia.
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Dislipidemias/tratamento farmacológico , Exercício Físico , Obesidade/tratamento farmacológico , Sobrepeso/tratamento farmacológico , Spirulina , Adulto , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Colesterol/metabolismo , HDL-Colesterol/sangue , HDL-Colesterol/metabolismo , LDL-Colesterol/sangue , LDL-Colesterol/metabolismo , Estudos Cross-Over , Dieta , Suplementos Nutricionais , Método Duplo-Cego , Dislipidemias/sangue , Humanos , Lipídeos/sangue , Masculino , Obesidade/sangue , Sobrepeso/sangue , Triglicerídeos/sangue , Triglicerídeos/metabolismoRESUMO
Excess weight and obesity are major risk factors for many chronic diseases, and weight-loss interventions often include systematic exercise and nutritional supplements. The purpose of this study was to determine the independent/synergistic effects of Arthrospira (Spirulina) maxima supplementation (six weeks, 4.5 g·day-1) and a systematic physical exercise program (six weeks, twice weekly) on the body composition and cardiorespiratory fitness of overweight and obese subjects. To achieve this, 27 overweight and 25 obese sedentary male subjects were assigned to four interventions through a randomized double-blind, crossover controlled trial: A physical exercise program, with (SE) or without (Ex) Spirulina maxima; or no-exercise program, with (Sm) and without (C) Spirulina maxima. The body composition and cardiorespiratory fitness parameters were taken during a maximum intensity test. As compared to the C group, the body fat percentage of the SE, Sm and Ex groups was reduced (p < 0.05), while their maximal oxygen uptake improved (r = -0.40), and obese subjects benefited more significantly. Weight loss, the time to reach fatigue and the onset of blood lactate accumulation were improved in both of the Spirulina maxima supplemented groups, regardless of the subjects' body weight. Spirulina maxima supplementation synergistically improves the effects of systematic exercise on body composition and cardiorespiratory fitness parameters in overweight, but mostly in individuals with obesity. TRIAL REGISTRATION: Clinical Trials, NCT02837666. Registered 19 July 2016.
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Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Sobrepeso/tratamento farmacológico , Sobrepeso/fisiopatologia , Spirulina/química , Adulto , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Suplementos Nutricionais , Método Duplo-Cego , Terapia por Exercício/métodos , Humanos , Masculino , Obesidade/tratamento farmacológico , Obesidade/fisiopatologia , Redução de Peso/efeitos dos fármacos , Redução de Peso/fisiologiaRESUMO
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.
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Bullying/estatística & dados numéricos , Emigrantes e Imigrantes/estatística & dados numéricos , Violência/estatística & dados numéricos , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Masculino , México , População Urbana , Adulto JovemRESUMO
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.
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Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Síndrome Metabólica/epidemiologia , Circunferência da Cintura , Adolescente , Adulto , Biomarcadores , Estudos Transversais , Feminino , Humanos , Masculino , México/epidemiologia , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Adulto JovemRESUMO
Anthocyanins (ACNs) are plant secondary metabolites from the flavonoid family. Red to blue fruits are major dietary sources of ACNs (up to 1 g/100 g FW), being cyanidin-3-O-glucoside (Cy3G) one of the most widely distributed. Cy3G confers a red hue to fruits, but its content in raspberries and strawberries is low. It has a good radical scavenging capacity (RSC) against superoxide but not hydroxyl radicals, and its oxidative potential is pH-dependent (58 mV/pH unit). After intake, Cy3G can be metabolized (phases I, II) by oral epithelial cells, absorbed by the gastric epithelium (1%-10%) and it is gut-transformed (phase II & microbial metabolism), reaching the bloodstream (<1%) and urine (about 0.02%) in low amounts. In humans and Caco-2 cells, Cy3G's major metabolites are protocatechuic acid and phloroglucinaldehyde which are also subjected to entero-hepatic recycling, although caffeic acid and peonidin-3-glucoside seem to be strictly produced in the large bowel and renal tissues. Solid evidence supports Cy3G's bioactivity as DNA-RSC, gastro protective, anti-inflammatory, anti-thrombotic chemo-preventive and as an epigenetic factor, exerting protection against Helicobacter pylori infection, age-related diseases, type 2 diabetes, cardiovascular disease, metabolic syndrome and oral cancer. Most relevant mechanisms include RSC, epigenetic action, competitive protein-binding and enzyme inhibition. These and other novel aspects on Cy3G's physical-chemistry, foodomics, and health effects are discussed.
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The fruit of Guamúchil is an excellent source of bioactive compounds for human health although their natural occurrence could be affected by the ripening process. The aim was to evaluate some physicochemical, chemical and antioxidant changes in guamúchil fruit during six ripening stages (I to VI). A defined trend (p ≤ 0.003) was observed for color [°Hue, 109 (light green) to 20 (dark red)], anthocyanins (+571 %), soluble solids (+0.33 oBrix), ash (+16 %), sucrose (-91 %), proanthocyanidins (63 %), ascorbic acid (-52 %) and hydrolysable PC (-21 %). Carotenoids were not detected and chlorogenic acid was the most abundant phenolic compound. Maximal availability of these bioactives per ripening stage (p ≤ 0.03) was as follows: I (protein/ lipids/ sucrose/ proanthocyanidins/ hydrolysable phenolics), II (total sugars/ascorbic acid), III (total phenolics), IV (flavonoids/ chlorogenic acid) and VI (fructose/ glucose/ anthocyanins). Color change was explained by sucrose (ß = 0.47) and anthocyanin (ß = 0.20) contents (p < 0.001). Radical scavenging capacity (ORAC, DPPH and TEAC) strongly correlated with total PC (r = 0.49-0.65, p ≤ 0.001) but 89 % of ORAC's associated variance was explained by anthocyanin + sucrose + ascorbic acid (p ≤ 0.0001). Guamúchil fruit could be a more convenient source of specific bioactive compounds if harvested at different ripening stages.
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Antioxidantes/análise , Fabaceae/química , Frutas/química , Compostos Fitoquímicos/análise , Antocianinas/análise , Ácido Ascórbico/análise , Carotenoides/análise , Ácido Clorogênico/análise , Modelos Lineares , Fenóis/análiseRESUMO
Purpose: In this study we evaluated the reliability of blood lactate levels (BLa), energy expenditure and substrate utilization during prolonged exercise at the intensity that elicits maximal fat oxidation (FATmax). Furthermore, we investigated the accuracy of a single graded exercise test (GXT) for predicting energy metabolism at FATmax. Methods: Seventeen young men with obesity (26 ± 6 years; 36.4 ± 7.2 %body fat) performed a GXT on a treadmill in a fasted state (10-12 h) for the assessment of FATmax and cardiorespiratory fitness. Afterward, each subject performed two additional prolonged FATmax trials (102 ± 11 beats·min-1; 60-min) separated by 7 days. Indirect calorimetry was used for the assessment of energy expenditure and substrate utilization kinetics whereas capillary blood samples were taken for the measurement of BLa. Results: The BLa (limits of agreement (LoA): -1.2 to 0.8 mmolâL-1; p = 1.0), fat utilization (LoA: -8.0 to 13.4 gâh-1; p = 0.06), and carbohydrate utilization (LoA: -27.6 to 22.4 gâh-1; p = 0.41) showed a good agreement whereas a modest systematic bias was found for energy expenditure (LoA: -16811 to 33355 kJâh-1; p < 0.05). All the aforementioned parameters showed a moderate to good reliability (Intraclass correlation coefficient: 0.67-0.92). The GXT overestimated fat (~46%) and carbohydrate (~26%) utilization as well as energy expenditure (36%) during steady-state exercise at FATmax. Conversely the GXT underestimated BLa (~28%). Conclusion: a single GXT cannot be used for an accurate prediction of energy metabolism during prolonged exercise in men with obesity. Thus, an additional steady-state FATmax trial (40-60 min) should be performed for a tailored and precise exercise prescription.
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This study investigates the immediate effects of acute postural exercises on the stature of seniors, focusing on changes in both upright and supine stature measurements. A within-subject design with repeated measures was applied, involving seniors participating in continuous exercises aimed at enhancing core musculature strength and promoting muscle relaxation. Stature measurements were recorded pre- and post-exercise in both upright and supine positions, alongside assessments of body mass index (BMI) category classifications. The results revealed a post-exercise increase in stature ranging from 0.9 to 6.0 cm and from 0.2 to 7.2 cm in upright and supine positions, respectively, with an average increase of approximately 3.5 cm in both upright and supine positions. Statistically significant and clinically relevant changes were observed (p < 0.05), including a modification of BMI by approximately two units, reclassifying 55% of participants from overweight or obese to normal weight or overweight. Furthermore, the similarity between post-exercise upright stature and pre-exercise supine stature suggested that the supine position might provide a more accurate measure of stature in seniors. Conclusively, acute postural exercises have an immediate positive impact on the stature of seniors, suggesting their potential utility in clinical settings for accurate stature measurement. However, BMI results should be interpreted with caution because they are only related to the acute change in stature and therefore may lead to the misinterpretation of the study findings, so future studies focused on evaluating the chronic effect of postural exercises integration on the health outcomes of older adults are needed to demonstrate their potential utility in clinical settings to improve postural health and general well-being.
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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.
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Bullying , Instituições Acadêmicas/estatística & dados numéricos , Autorrelato/normas , Estudantes/estatística & dados numéricos , Adolescente , Bullying/psicologia , Feminino , Humanos , Masculino , México/epidemiologia , Projetos Piloto , Psicometria/normas , Reprodutibilidade dos Testes , Estudantes/psicologia , Inquéritos e Questionários , Adulto JovemAssuntos
Bullying , Estudantes/psicologia , Inquéritos e Questionários , Adolescente , Bullying/estatística & dados numéricos , Criança , Feminino , Humanos , Masculino , México , Prevalência , Adulto JovemRESUMO
AIM: The aim of this paper was to study the feasibility of bench stepping at a low cadence as a safe exercise that can provide enough cardiovascular fitness that be performed by any person. METHODS: Thirty-three men and twenty-one young women (age =23±3 yrs; weight =70±13 kg; height 170±9 cm) participated in this study. Each one held a continuous 20 minute (4 stages /5 min each) bench stepping workout session with two different step heights (31 and 41 cm) and two different intensities (60 and 90 stepsâmin-1). Body weight (bw), total & trochanteric height, heart rate (HR, beatsâmin-1), rated perceived exertion (RPE) and O2 consumption (VO2) were recorded. RESULTS: From the 1st through the 4th stage, the vertical distance (VD, m), RPE, HR and VO2 values were 4.6-9.23 m, 2.5-6.7, 118-168 beatsâmin-1 and 20.8-34.0 mlâkg-1âmin-1, respectively. The best regression model to calculate the O2 consumption (VO2) was: VO2 (Lâmin-1) =-1.264+0.026âbw (kg)+0.195âVD (m). VD, bw, and gender determined, independently, the changes of caloric expenditure (R2=0.92). CONCLUSION: The energy expenditure of a low cadence stepping exercise (15-22 cyclesâmin-1) at 31-41 cm bench height, is enough to improve aerobic fitness which in turn may benefit cardiovascular health.
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Fenômenos Fisiológicos Cardiovasculares , Metabolismo Energético , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Aptidão Física/fisiologia , Adolescente , Adulto , Antropometria , Feminino , Humanos , Modelos Lineares , MasculinoRESUMO
BACKGROUND: Exercise training performed at maximal fat oxidation (FATmax) is an efficient non-pharmacological approach for the management of obesity and its related cardio-metabolic disorders. OBJECTIVES: Therefore, this work aimed to provide exercise intensity guidelines and training volume recommendations for maximizing fat oxidation in patients with obesity. METHODS: A systematic review of original articles published in English, Spanish or French languages was carried out in EBSCOhost, PubMed and Scopus by strictly following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. Those studies that analyzed maximal fat oxidation (MFO) and FATmax in patients with obesity (body fat > 25% for men; > 35% for women) by calculating substrate oxidation rates through indirect calorimetry during a graded exercise test with short-duration stages (< 10 min) were selected for quantitative analysis. The accuracy of relative oxygen uptake (% peak oxygen uptake [%[Formula: see text]O2peak]) and relative heart rate (% peak heart rate [%HRpeak]) for establishing FATmax reference values was investigated by analyzing their intra-individual and inter-study variation. Moreover, cluster analysis and meta-regression were used for determining the influence of biological factors and methodological procedures on MFO and FATmax. RESULTS: Sixty-four manuscripts were selected from 146 records; 23 studies only recruited men (n = 465), 14 studies only evaluated women (n = 575), and 27 studies included individuals from both sexes (n = 6434). The majority of the evaluated subjects were middle-aged adults (aged 40-60 y; 84%) with a poor cardiorespiratory fitness (≤ 43 mL·kg-1·min-1; 81%), and the reported MFO ranged from 0.27 to 0.33 g·min-1. The relative heart rate at FATmax (coefficient of variation [CV]: 8.8%) showed a lower intra-individual variation compared with relative oxygen uptake (CV: 17.2%). Furthermore, blood lactate levels at FATmax ranged from 1.3 to 2.7 mmol·L-1 while the speed and power output at FATmax fluctuated from 4 to 5.1 km·h-1 and 42.8-60.2 watts, respectively. Age, body mass index, cardiorespiratory fitness, FATmax, the type of ergometer and the stoichiometric equation used to calculate the MFO independently explained MFO values (R2 = 0.85; p < 0.01). The MFO in adolescents was superior in comparison with MFO observed in young and middle-aged adults. On the other hand, the MFO was higher during treadmill walking in comparison with stationary cycling. Body fat and MFO alone determined 29% of the variation in FATmax (p < 0.01), noting that individuals with body fat > 35% showed a heart rate of 61-66% HRpeak while individuals with < 35% body fat showed a heart rate between 57 and 64% HRpeak. Neither biological sex nor the analytical procedure for computing the fat oxidation kinetics were associated with MFO and FATmax. CONCLUSION: Relative heart rate rather than relative oxygen uptake should be used for establishing FATmax reference values in patients with obesity. A heart rate of 61-66% HRpeak should be recommended to patients with > 35% body fat while a heart rate of 57-64% HRpeak should be recommended to patients with body fat < 35%. Moreover, training volume must be higher in adults to achieve a similar fat oxidation compared with adolescents whereas exercising on a treadmill requires a lower training volume to achieve significant fat oxidation in comparison with stationary cycling.
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Tecido Adiposo , Exercício Físico , Adulto , Masculino , Pessoa de Meia-Idade , Adolescente , Humanos , Feminino , Exercício Físico/fisiologia , Tecido Adiposo/metabolismo , Oxirredução , Obesidade/terapia , Teste de Esforço , Oxigênio/metabolismo , Consumo de OxigênioRESUMO
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 mmolâL-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 beatsâmin-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 beatsâmin-1; CCC=0.77), VT1 (R2= 0.76; SEE= 5 beatsâmin-1; CCC=0.84) and LIAB (R2= 0.77; SEE= 5 beatsâmin-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 beatsâmin-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.
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Metabolismo dos Lipídeos , Consumo de Oxigênio , Masculino , Humanos , Consumo de Oxigênio/fisiologia , Metabolismo dos Lipídeos/fisiologia , Calorimetria Indireta , Teste de Esforço , Obesidade , Ácido LácticoRESUMO
Food selectivity (FS) in children with autism spectrum disorders (ASD) is common, and its impact on a nutritional level is known. However, the etiology of gastrointestinal disorders (GID) related to alterations in the intestinal microbiota in children with ASD remains unclear. This article provides a narrative review of the literature on FS from the last 15 years, and its relationship with GID in children with ASD. Sensory aversion in ASD leads to food elimination, based on consistencies, preferences, and other sensory issues. The restriction of food groups that modulate the gut microbiota, such as fruits and vegetables, as well as the fibers of some cereals, triggers an intestinal dysbiosis with increased abundance in Enterobacteriaceae, Salmonella Escherichia/Shigella, and Clostridium XIVa, which, together with an aberrant immune response and a leaky gut, may trigger GID. It is observed that FS can be the product of previous GID. GID could provide information to generate a hypothesis of the bidirectional relationship between FS and GID. Emphasis is placed on the need for more studies with methodological rigor in selecting children with ASD, the need for homogeneous criteria in the evaluation of GID, and the adequate classification of FS in children with ASD.
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Transtorno do Espectro Autista , Gastroenteropatias , Microbioma Gastrointestinal , Transtorno do Espectro Autista/complicações , Criança , Disbiose/complicações , Preferências Alimentares , Gastroenteropatias/complicações , HumanosRESUMO
Fatty acid translocase/cluster of differentiation 36 (FAT/CD36) is a multifunctional membrane protein activated by a high-fat diet, physical exercise, fatty acids (FAs), leptin, and insulin. The principal function of FAT/CD36 is to facilitate the transport of long-chain fatty acids through cell membranes such as myocytes, adipocytes, heart, and liver. Under high-energy expenditure, the different isoforms of FAT/CD36 in the plasma membrane and mitochondria bind to the mobilization and oxidation of FAs. Furthermore, FAT/CD36 is released in its soluble form and becomes a marker of metabolic dysfunction. Studies with healthy animals and humans show that physical exercise and a high-lipid diet increase FAT/CD36 expression and caloric expenditure. However, several aspects such as obesity, diabetes, Single Nucleotide polymorphisms (SNPs), and oxidative stress affect the normal FAs metabolism and function of FAT/CD36, inducing metabolic disease. Through a comprehensive systematic review of primary studies, this work aimed to document molecular mechanisms related to FAT/CD36 in FAs oxidation and trafficking in skeletal muscle under basal conditions, physical exercise, and diet in healthy individuals.
RESUMO
Introduction: Background: gastrointestinal disorders (GIDs) are common comorbidities in patients with autism spectrum disorders (ASD); treatments with gluten- and casein-free (LGLC) diets or prebiotic/probiotic supplements may reduce the severity of GIDs. Objective: to integrate and discuss the evidence on the effectiveness of LGLC diet therapies and prebiotic/probiotic supplements on GIDs in patients with ASD. Methodology: the guidelines for the publication of systematic reviews and meta-analyses (PRISMA) were used. Participant characteristics, dietary interventions, prebiotic/prebiotic supplementation, effects of interventions on GIDs, risk of bias, and safety of treatments were analyzed. Results: fifteen investigations were analyzed; the prevalence of GIDs among patients with ASD was high (58 %; range, 27-83 %). In more than 20 % of the patients managed with LGLC diets or supplements GID severity decreased (mainly constipation, diarrhea, and abdominal pain). Increases in the counts of beneficial bacteria and a decrease in the proportion of pathogenic bacteria were reported after supplement use. However, all these investigations had significant methodological biases. Conclusions: although reductions in the frequency and severity of some GIDs have been found, the effectiveness of these treatments has not been proven yet. Given the methodological differences in the investigations, the design of rigorous studies to evaluate the therapeutic effects of these treatments on gastrointestinal health in patients with ASD is warranted.
Introducción: Antecedentes: los trastornos gastrointestinales (TGI) son comorbilidades comunes en los pacientes con trastornos del espectro autista (TEA); los tratamientos con dietas libres de gluten y caseína (LGLC) o suplementos de prebióticos/probióticos podrían reducir la severidad de los TGI. Objetivo: integrar y discutir la evidencia sobre la efectividad de las terapias con dietas LGLC y suplementos de prebióticos/probióticos sobre los TGI en pacientes con TEA. Metodología: se utilizaron las guías para la publicación de revisiones sistemáticas y metaanálisis (PRISMA). Se analizaron las características de los participantes, las intervenciones dietéticas, la administración de suplementos de prebióticos/prebióticos, los efectos de las intervenciones sobre los TGI, el riesgo de sesgo de los estudios y la seguridad de los tratamientos. Resultados: se analizaron quince investigaciones; la prevalencia de los TGI entre los pacientes con TEA fue alta (58 %; rango, 27-83 %). En más del 20 % de los pacientes intervenidos con dietas LGLC o suplementos disminuyó la severidad de los TGI (principalmente estreñimiento, diarrea y dolor abdominal). Se reportaron aumentos en los conteos de bacterias benéficas y una disminución de la proporción de bacterias patógenas tras el uso de los suplementos. Sin embargo, todas estas investigaciones presentaron sesgos metodológicos importantes. Conclusiones: aunque se han encontrado reducciones en la frecuencia y severidad de algunos TGI, la efectividad de estos tratamientos aún no se ha comprobado. Dadas las diferencias metodológicas de las investigaciones, se justifica el diseño de estudios rigurosos para evaluar los efectos terapéuticos de estos tratamientos sobre la salud gastrointestinal en pacientes con TEA.
Assuntos
Transtorno do Espectro Autista , Gastroenteropatias , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/terapia , Dieta , Suplementos Nutricionais , Gastroenteropatias/complicações , Gastroenteropatias/terapia , Humanos , PrebióticosRESUMO
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.
Assuntos
Estatura , Idoso , Feminino , Humanos , Masculino , Antropometria/métodos , Etnicidade , Modelos Lineares , Pessoa de Meia-IdadeRESUMO
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.