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PURPOSE: Compare tracking groups with cognitive control functions and plasma brain-derived neurotrophic factors concentrations from childhood to adolescence. METHODS: This is a prospective study with 3 years of follow-up. At baseline, data from 394 individuals were collected (11.7 y), and data were obtained from 134 adolescents (14.9 y) at the 3-year follow-up. At both time points, anthropometric and maximal oxygen uptake data were collected. Cardiorespiratory fitness (CRF) groups were classified into high or low CRF. At follow-up, cognitive outcomes were collected via the Stroop and Corsi block test; plasma brain-derived neurotrophic factors concentrations were also analyzed. RESULTS: Comparisons demonstrated that maintaining high CRF over 3 years results in shorter reaction time, better inhibitory control, and higher working memory values. Likewise, the group that moved from low to high CRF over 3 years presented better reaction time. Plasma brain-derived neurotrophic factors concentrations were higher for the group that increased its CRF over the 3 years in relation to the low-low group (90.58 pg·mL-1; P = .004). However, after scaling by an allometric approach, differences were only found for reaction time and working memory between high-high and high-low groups. CONCLUSION: Maintaining high CRF over 3 years was positively related to reaction time and working memory in relation to adolescents that decreased their levels of CRF.

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BACKGROUND: Metabolic syndrome (MetS) is a group of diseases characterized by insulin resistance. MetS has high prevalence among women, which is impacted by food intake. MetS is related to high level of inflammation; however, the impacts of whole diets on biochemical and anthropometrical markers and the effects on MetS need to be further elucidated. In this case, the objective of this study was to assess the relationship between food intake, biochemical and anthropometrical markers in women with MetS. METHODS: This is a cross-sectional study, in which 1 hundred and 22 women participated in the assessment of biochemical (glycated hemoglobin, glycaemia, insulin, uric acid, total cholesterol, HDL-c, LDL-c, triglycerides, C-reactive protein) and anthropometrical (body mass, height, waist circumference - WC) variables. Participants also performed blood pressure and 24-hour dietary recall assessments. Out of the 122 participants, 44 (36%, age: 59 ± 11 years) had MetS and were included in the analysis. RESULTS: The consumption of monounsaturated fats had direct relationship with glycaemia (b = 7.48), whereas the consumption of fibers had inverse relationship with body mass (b = - 0.71) and WC (b = - 0.56). CONCLUSION: The intake of monounsaturated fats and fiber was related to higher blood sugar levels and lower body mass and WC, respectively. These relationships elucidate and highlight the significance and importance of adequate diet in women with MetS.

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We aimed to characterize the age of onset of training, age at menarche, menstrual periodicity, and performance perception during the menstrual cycle and examined the impact of these reproductive variables on body composition, morphology, and body weight satisfaction in Brazilian elite futsal players. The study consisted of 115 female Brazilian elite futsal players from the top national teams. Data were collected during the twentieth Women's Brazil Futsal Cup. Players were interviewed and self-reported their age of onset of training, age at menarche, menstrual periodicity, and the menstrual period, where they performed best. We also asked for what they considered to be their ideal body weight as well as information related to their training (i.e., volume and frequency). Subsequently, anthropometric measurements (i.e., body mass, height, circumferences, diameters, and skinfold thickness) were performed to estimate the body composition and determine morphological characteristics (e.g., somatotype). Fifty-nine (53.2%) players were postmenarche-trained and 52 (46.8%) were premenarche-trained. Eighteen (16.2%), 65 (58.6%), and 28 (25.2%) were classified as early, normal, and late menarche, respectively. Only 11 (9.6%) and 1 (0.9%) had irregular menstrual cycles and were amenorrheic, respectively. Seventy-three (69.5%), 23 (21.9%), and 9 (8.6%) reported that their game performance was the best at the follicular phase, menses, and luteal phase of the menstrual cycle, respectively. No associations between the four reproductive-related variables were found. Postmenarche-trained players had significant lower age at menarche and higher percentage body fat. The somatotype profile registered lower ectomorphy rate for the postmenarche-trained participants after controlling for covariates. Early menarche group presented higher sum of six skinfold thickness and endomorphy rate compared to normal and late menarche groups. No differences were found when menstrual periodicity groups and best performance groups were compared, except for higher femur width in the regular menstrual cycle group compared to the irregular one. The association between body weight satisfaction and the four reproductive-related variables were not observed. Premenarche-trained Brazilian elite futsal players had the menarche later than the postmenarche-trained athletes. Most of the participants had menarche age classified as "normal," presented "regular" menstrual cycles and perceived to perform better during the follicular phase of the menstrual cycle.

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BACKGROUND: Working memory performance is associated with better academic achievements in children and adolescents, and it is positively related to CRF. However, what level of cardiorespiratory fitness (CRF) discriminates higher working memory performance is not known. The purpose of this study was to identify CRF thresholds linked to working memory in adolescents. METHODS: Data of 141 adolescents (53.2 % girls) were collected (14.9 years) from a cross-sectional study during the year 2019. CRF was assessed by the 20-m shuttle run test, and maximal oxygen uptake was calculated using the Mahar´s equation. Working memory was evaluated by the Corsi blocks test and performance was classified by percentiles. Receiver operating characteristic (ROC) curve analysis was used to identify CRF thresholds. RESULTS: The ROC analysis indicated that CRF could be used to discriminate working memory in adolescents. CRF thresholds of ≥45.03 ml.kg- 1.min- 1for boys and ≥36.63 ml.kg- 1.min- 1for girls were found to be indicative of "normal" working memory performance. CONCLUSIONS: CRF could discriminate low and normal working memory performance in 14-16- year-old adolescents. These thresholds could allow for earlier identification and intervention of low working memory performance using CRF.

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OBJECTIVE: Evaluate the effects of Myofascial release (MR) on lower limb ROM, sit and reach and horizontal jump distance in male university students. STUDY DESIGN: Quasi-experimental study. BACKGROUND: MR is a technique that aims to stretch fascia to increase range of motion (ROM), relieve pressure points and improve performance. However, there is limited evidence of its actual effects on flexibility and physical performance. METHODS: Twenty-one uninjured, male university students received MR (11 on the first session and the other 10 on the second session 24 h later), completed lower limb ROM assessments, the sit and reach and the horizontal jump tests in a randomized order. MR was performed before the tests with a myofascial stick in the anterior and posterior aspects of the right and left thigh and calf muscles. Each muscle group was massaged for 90 s, totaling 9 min of MR. The testing conditions with MR and without MR were compared using Student t-tests and the effect sizes (ES) were calculated. RESULTS: There were no significant differences between the testing conditions on horizontal jump distance. However, the sit and reach distance (28 ± 9 vs. 32 ± 9 cm, p = 0.001; ES = 0.44), left hip extension (10 ± 2 vs. 8 ± 2°, p = 0.006; ES = 1.00) and left plantar flexion (36 ± 7 vs. 39 ± 7°, p = 0.044; ES = 0.43) were higher with MR. CONCLUSIONS: MR increased sit and reach distance, left hip extension and plantar flexion, but it did not affect horizontal jump distance in uninjured, male university students.

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Abstract Aims: This study aimed to measure light-intensity physical activity (LPA) patterns in adolescents according to weekdays and school period and investigated associations between LPA patterns and associated factors. Methods: This is a cross-sectional study with 388 students of both genders, selected from public schools from Londrina city, Parana state. LPA was measured using accelerometry for seven consecutive days and was analyzed by the time spent in very short (15 to 30 s), short (30 to 60 s), intermediate (1 to 3 min), and long bouts (≥ 3 min). Results: Approximately 22% of the total daily time was spent in LPA. The time in LPA accumulated in short or intermediate bouts was higher than the time accumulated in very short or long bouts (P < 0.05). Gender was associated with short (β= 2.180; 95% confidence interval [CI], 0.357 to 4.003) and intermediate bouts (β = 2.822; 95% CI, 0.681 to 4.964), girls presented higher daily time. Age was inversely associated with very short (β = −0.925; 95% CI, −1.676 to −0.175) and intermediate bouts (β = −1.985; 95% CI, −3.579 to −0.390). The total time in LPA and time accumulated in very short, short, and intermediate bouts was higher in the school period when compared to the non-school period (P < 0.05). Conclusion: It could be concluded that the LPA patterns are predominantly composed of time spent in bouts between 30 seconds and three minutes. Gender, age, and school period appear to influence the LPA pattern in adolescents.

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BACKGROUND: High-intensity training methods are generally recommended to increase muscle mass and strength, with training loads of 60-70% 1RM for novice and 80-100% 1RM for advanced individuals. Blood flow restriction training, despite using lower intensities (30-50% 1RM), can provide similar improvements in muscle mass and strength. However, studies commonly investigate the effects of blood flow restriction training in large muscular groups, whereas there are few studies that investigated those effects in smaller muscle groups, such as the muscles involved in grasping (e.g, wrist flexors; finger flexors). Clinically, smaller muscular groups should also be considered in intervention programs, given that repetitive stress, such as repeated strain injuries, affects upper limbs and may lead to chronic pain and incapacity for work. The purpose of the present study was to examine the effects of blood flow restriction training in strength and anthropometric indicators of muscular volume in young women. HYPOTHESIS: The effect of blood flow restriction training in handgrip strength (HGS) and muscular volume of young women can be similar to traditional training, even with lower loads. METHODS: Twenty-eight university students, 18 to 25 years of age, were randomly assigned into two groups, blood flow restriction training (BFR, n = 14) and traditional training (TRAD, n = 14). The anthropometric measures and maximum handgrip strength (MHGS) test were performed before and after the intervention. The participants did three weekly sessions of dynamic concentric contraction exercises on a dynamometer for four weeks (12 sessions). Each session had a time length of five minutes and the intensity was established from a percentage of MHGS at 30-35% in the first week, 40-45% in the second and 50-55% in third/fourth weeks. Three sets of 15-25 handgrip repetitions were performed until a failure with a 30 seconds rest for BFR training and three sets of 8-12 repetitions with one-minute rest for TRAD training. RESULTS: A significant increase was found in the arm muscle circumference (20.6 ± 2.2 vs 21.6 ± 1.7cm) and right MHGS (32.7 ± 4.5 vs 34.3 ± 4.1 kgf) and left MHGS (28.0 ± 5.5 vs 30.9 ± 4.1 kgf) for the BFR training, and the left MHGS (27.6 ± 5.0 vs 31.0 ± 6.1 kgf) for the TRAD training. CONCLUSION: Dynamometer training with blood flow restriction, performed with low to moderate loads, was more effective than the traditional training in increasing HGS and muscle volume in young women. LEVEL OF EVIDENCE: 2b.

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Objetivo: analisar os efeitos do consumo de chá verde associado ao exercício físico sobre a composição corporal de pessoas obesas. Materiais e método: o estudo trata-se de uma revisão sistemática de literatura. As buscas foram feitas nas bases de dados Lilacs, Scielo e PubMed, utilizando os descritores: obesidade, chá verde, Camellia Sinensis, exercício. Os artigos utilizados foram publicados entre os anos de 2003 a 2015. Resultados: uma ferramenta recentemente utilizada para o controle do peso é o chá verde, considerado um alimento funcional; é a segunda bebida mais consumida no mundo. Evidências mostram seu efeito termogênico com aumento do gasto energético e promoção da oxidação de gorduras. O consumo de chá verde se mostrou efetivo na diminuição de massa corporal, especialmente na forma de gordura, porém o consumo do chá aliado à prática de exercício se mostra mais eficaz para a redução de peso. Ressalta-se ainda que os hábitos alimentares saudáveis devem ser incentivados para obter o máximo dos benefícios dessa planta. Considerações finais: é necessária a investigação mais aprofundada para determinar as doses e formas de administração seguras do chá verde, bem como os mecanismos de ação e da biodisponibilidade dos compostos ativos, pois se trata de um alimento de baixo custo e que pode ser utilizado no manejo nutricional de doenças crônicas como a obesidade, colaborando assim, para a qualidade de vida e saúde da população.(AU)

Objective: This study is a literature review on the effects of green tea consumption associated with exercise on obesity. Materials and method: Searches were made in the databases Lilacs, SciELO and PubMed. Results: One way recently used for weight control is green tea, considered a functional food, is the second most consumed beverage in the world. Evidence shows his thermogenic effect with increased energy expenditure and promoting fat oxidation. The consumption of green tea was effective in decreasing body weight, especially in the form of fat, but tea consumption combined with exercise training proves more effective for weight reduction. It is noteworthy that healthy eating habits should be encouraged to get the maximum benefits of this plant. Closing remarks: It is required further investigation to determine the doses and secure administration of green tea, as well as the mechanisms of action and bioavailability of the active compounds, since it is an inexpensive food which can be used for the nutritional management of diseases chronic such as obesity, thus contributing to the quality of life and health.(AU)

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