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BACKGROUND: Dual-energy X-ray absorptiometry (DXA) measures are affected by the noise produced by external factors such as textile compression found in loose clothing. The study aimed to determine the effect of a compression bandage (CB) on body composition (BC) assessed by DXA. METHODS: Sixty volunteers (age=21.4±4.7yr.) underwent full-body DXA scans on a control (CTRL) condition and after wearing a 30-mmHg CB on the trunk, legs, and arms. ANOVA (2 genders by 2 experimental conditions) determined mean interactions in BC variables tissue body fat% (BF%), region body fat% (RBF%), body tissue (BT), fat mass (FM), lean mass (LM), bone mineral content (BMC), and total mass (TM). Absolute reliability in BC scores was studied by the typical error of the measurement (TEM), the coefficient of variability (CV), and Bland-Altman plots. RESULTS: ANOVA interactions were found on tissue total BF% (p=0.049), RBF% (p=0.048), android lean mass (p=0.004), and android total mass (p=0.019). The CV was small for tissue BF% (2.61±0.93%, CI95%=0.79, 4.43%), RBF% (2.66±1.78%, CI95%=-0.83, 6.15%), BT (4.82±2.19%, CI95%=0.54, 9.10kg), FM (4.17±2.25%, CI95%=-0.24, 8.58kg), LM (3.25±2.44%, CI95%=-1.53, 8.04kg), BMC (4.81±2.96%, CI95%=-0.99, 10.62kg), and TM (2.84±2.80%, CI95%=-2.65, 8.33kg). Bland-Altman plots showed random error for BF%, LM, and BMC. A bias of 0.5% was observed on BF% in males. CONCLUSION: A CB worn during a full-body DXA scan elicited similar BC scores than not wearing it. The variation in scores was <10% for most BC variables, and a trivial bias of 0.5% in BF% was detected in male scores.
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Tecido Adiposo , Composição Corporal , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Absorciometria de Fóton , Reprodutibilidade dos Testes , Densidade ÓsseaRESUMO
We studied the effect of exercise-induced body fluid redistribution on dual-energy x-ray absorptiometry (DXA) body composition scores. Thirty males completed 30-min of upper-body exercise (UBE), lower-body exercise, and seated non-exercise control (NEC). ANOVA determined interactions between experimental conditions and measurements on body composition variables. For UBE, mean pre to post differences were found on tissue fat (M = 0.35 ± 0.12%; CI95%diff = 0.10 to 0.59%; p = 0.007), region fat (M = 0.32 ± 0.11%; CI95%diff = 0.09 to 0.55%; p = 0.008), lean mass (M = 0.27 ± 0.01 kg; CI95%diff = 0.18 to 0.37 kg; p ≤ 0.0001), and total mass (M = 0.27 ± 0.05 kg; CI95%diff = 0.17 to 0.36 kg; p ≤ 0.0001). Mean tissue pre to post differences were found for the total body in the NEC (M = 0.10 ± 0.04 kg; CI95%diff = 0.03 to 0.18 kg; p = 0.008), UBE (M = 0.19 ± 0.03 kg; CI95%diff = 0.14 to 0.24 kg; p ≤ 0.0001), and LBE (M = 0.31 ± 0.04 kg; CI95%diff = 0.24 to 0.39 kg; p ≤ 0.0001) conditions. High absolute reliability was found within experimental conditions. These findings have practical implications for technicians, since acute exercise elicited small changes in body composition scores using DXA.
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Absorciometria de Fóton , Composição Corporal , Exercício Físico , Humanos , Masculino , Exercício Físico/fisiologia , Composição Corporal/fisiologia , Adulto Jovem , Adulto , Líquidos Corporais/fisiologiaRESUMO
BACKGROUND: Valid and reliable measurements are necessary to understand and monitor age-related changes. AIMS: To describe the factor structure and provide validity evidence of a neuropsychological and a physical testing batteries using factor analysis. METHODS: We performed a secondary analysis of data from the Epidemiology and Development of Alzheimer's Disease (EDAD) project. Community-dwelling adults aged 55 to 85 years underwent comprehensive physical and neuropsychological assessments. An exploratory factor analysis was performed on both assessment batteries. The models were later confirmed with a random subsample using confirmatory factor analysis. RESULTS: Data from 238 adults (163 females and 75 males) was included. The neuropsychological model revealed a four-factor structure formed by "Executive Functioning", "Verbal Memory", "Logical Memory", and "Labeling And Reading" (Extraction Sums of Squared Loadings [ESSL] = 56.41% explained variance; Standardized Root Mean Square Residual [SRMSR] = 0.06; Comparative Fit Index [CFI] = 0.98). The physical model was formed by a two-factor structure including "Health-related Fitness and "Functional Fitness" (ESSL = 50.54% explained variance; SRMSR = 0.07; CFI = 0.93). DISCUSSION: To our knowledge, this is the first study to analyze the structure of comprehensive testing batteries for the Latin-American older adults. Our analysis contributes to the understanding of theoretical constructs that are evaluated in the EDAD project. CONCLUSION: Our findings provide validity evidence for simplified and reduced testing batteries, which imply shorter testing times and fewer resources.
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Doença de Alzheimer , Função Executiva , Idoso , Feminino , Humanos , Masculino , Doença de Alzheimer/diagnóstico , Memória , Testes Neuropsicológicos , Exame Físico , Reprodutibilidade dos Testes , Pessoa de Meia-Idade , Idoso de 80 Anos ou maisRESUMO
ABSTRACT: Briceño-Torres, JM, Carpio-Rivera, E, Solera-Herrera, A, Forsse, J, Grandjean, PW, and Moncada-Jiménez, J. Low-intensity resistance training improves flow-mediated dilation in young hispanic adults. J Strength Cond Res 37(2): 298-304, 2023-The purpose of this study was to compare the effects of 2 resistance exercise training (RET) intensities on brachial artery flow-mediated dilatation (FMD) in sedentary males. Thirty-four men (age = 20.6 ± 1.8 years, height = 171.3 ± 5.2 cm, body mass = 65.2 ± 10.6 kg, and DXA fat mass = 22.3 ± 7.4%) were randomly assigned to a control group (no exercise CTRL, n = 12), RET at 50% of 1 repetition maximum (1RM) (RET50%, n = 12), and RET at 80% 1RM (RET80%, n = 10). The RET program was performed twice per week for 8 weeks; subjects performed the same RET exercises at similar total workloads (1920 arbitrary units [AUs] for the RET80% and 1950 AUs for the RET50%). The FMD% was measured before and after 8 weeks by ultrasound. Mixed factorial analysis of variance (3 groups × 2 measurements), effect size (ES), and 95% confidence intervals (95% CIs) were computed for FMD%. The level of significance was set at p ≤ 0.05. A significant increase ( p = 0.001) was found on post-test FMD% in RET50% (mean = 9.9 ± 3.7%, ES = 1.9, and 95% CIs = 2.8-0.9) compared with CTRL (mean = 5.7 ± 1.7%, ES = 0.2, and 95% CIs = -0.4 to 0.8), and there were no significant differences found between RET50% and RET80% and between RET80% and CTRL. Results support the concept of training specificity and provide preliminary evidence that lower resistance and higher repetition RET elicit greater short-term reduced endothelium dysfunction than higher intensity RET at similar training volume.
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Treinamento Resistido , Masculino , Humanos , Adulto , Adolescente , Adulto Jovem , Treinamento Resistido/métodos , Dilatação , Terapia por Exercício , Exercício Físico , Hispânico ou Latino , Força Muscular , Músculo EsqueléticoRESUMO
Sarcopenia and disability in older adults are often characterized by body composition measurements; however, the gold standard of body composition measurement, dual-energy X-ray absorptiometry (DEXA), is expensive to acquire and maintain, making its use in low and middle income countries (LMIC) it out-of-reach in developing nations. Because these LMIC will bear a disproportionate amount of chronic disease burden due to global aging trends, it is important that reliable, low-cost surrogates need to be developed. Handgrip strength (HGS) is a reliable measure of disability in older adults but has not been used widely in diverse populations. This study compared HGS to multiple measurements of body composition in older adults from the US (Kansas) and a middle-income country (Costa Rica) to test if HGS is a cross-culturally appropriate predictive measure that yields reliable estimates across developed and developing nations. Percent body fat (%BF), lean tissue mass index (LTMI), appendicular lean soft tissue index (ALSTI), body fat mass index (BFMI), bone mineral density (BMD), and HGS were measured in older Costa Ricans (n = 78) and Kansans (n = 100). HGS predicted lean arm mass with equal accuracy for both samples (p ≤ 0.05 for all groups), indicating that it is a reliable, low-cost and widely available estimate of upper body lean muscle mass. Older adults from Costa Rica showed different body composition overall and HGS than controls from Kansas. Handgrip operates equivalently in the US and Mesoamerica and is a valid estimate of lean arm muscle mass as derived by the more expensive DEXA.
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Comparação Transcultural , Força da Mão , Humanos , Idoso , Força da Mão/fisiologia , Costa Rica , Kansas , Composição Corporal/fisiologia , Força Muscular/fisiologiaRESUMO
OBJECTIVE: To verify the validity of the body adiposity index (BAI) in a sample of Costa Rican students. METHODS: Volunteers were 93 females (mean age = 18.6 ± 2.4 years) and 106 males (mean age = 19.2 ± 2.8 years). Dual-energy X-ray absorptiometry (DXA) was used as the "gold standard" to determine body fat percentage (BF%). Pearson's correlation coefficient and paired samples t-test studied the association and mean differences between BAI and DXA BF%. Concordance between BAI and DXA BF% was determined by the Lin's concordance correlation coefficient and the Bland-Altman agreement analysis. RESULTS: Significant correlations between BAI and DXA BF% were found for females (r = 0.74) and males (r = 0.53) (P < 0.001). Differences between methods were found for females (BAI = 29.3 ± 4.1% vs. DXA = 36.5 ± 7.9%) and males (BAI = 24.8 ± 3.7% vs. DXA = 21.9 ± 8.6%; P < 0.001). Concordance was poor in females and males. Bland-Altman plots showed BAI underestimating and overestimating BF% in relation to the "gold standard" in females and males, respectively. CONCLUSIONS: BAI presented low agreement with BF% measured by DXA; therefore, BAI is not recommended for BF% prediction in this Central American sample studied. Am. J. Hum. Biol. 28:394-397, 2016. © 2015 Wiley Periodicals, Inc.
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Adiposidade , Antropometria/métodos , Estudantes/estatística & dados numéricos , Absorciometria de Fóton , Adolescente , Costa Rica , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto JovemRESUMO
To determine the acute effect of an energy drink (ED) on physical performance of professional female volleyball players. 19 females (age= 22.3 ± 4.9 yr.; height= 171.8 ± 9.4 cm; weight= 65.2 ± 10.1 kg) participated in a randomized, crossover, double-blind study to measure grip strength, vertical jump and anaerobic power in 3 different sessions (ED, placebo [PL] or no beverage [CTL]). For each session, participants arrived in a fasted state, consumed a standardized breakfast meal, and 1 hr later completed the 3 baseline performance tests without having ingested the beverage. After completing the premeasurements, the athletes drank 6 ml/kg of body weight of the ED or PL and in the CTL condition no beverage was consumed. Posttest measurements were taken 30 min after the ingestion of liquids. A 3 × 2 repeated-measures ANOVA revealed no significant within-session and measurement time interactions for each performance test. Regardless of the measurement time, right hand grip strength was significantly higher in the ED condition (34.6 ± 0.9 kg) compared with PL (33.4 ± 1.1 kg) and CTL (33.6 ± 1.0 kg) (p < 0.05). Regardless of the beverage ingested, averaged right hand grip strength, taking into account all 3 testing conditions, increased from pre to posttesting (Pre = 33.8 ± 0.9 kg vs. Post = 33.9 ± 1.0 kg; p = 0.029), as did the averaged fatigue index, obtained from the anaerobic power test (Pre = 65.9± 2.2% vs. Post = 68.7± 2.0%; p= 0.049). The acute ingestion of an ED did not improve physical performance of professional Costa Rican female volleyball players.
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Limiar Anaeróbio/fisiologia , Desempenho Atlético/fisiologia , Bebidas Energéticas , Força da Mão/fisiologia , Voleibol/fisiologia , Adulto , Costa Rica , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto JovemRESUMO
BACKGROUND: Decreases in function of the immune system with age contribute to the increase the risk of infectious diseases especially the upper respiratory tract. On the other hand, physical activity has been widely recommended for health. However, more studies are needed to support the benefit effect of exercise on immune system in elderly. AIM: To evaluate the effect of the hydrogymnastics on the serum level of immunoglobulin A (IgA) in elderly women. METHODS: Twenty-six participants were randomly assigned to an experimental (n: 16) or a control group (n: 10). IgA concentrations were determined by nephelometry (BN2 Analyzer, Dade Behring). The hydrogymnastics training protocol was performed 5 times a week during 12 weeks. The intensity of the aerobic exercise was 50-60% of the maximum heart rate monitored by telemetry (Polar-FT7). RESULTS: No significant differences (p: 0.797) resulted by ANOVA on serum IgA levels; the percentage of change in experimental group was Δ% = -6.7 mg/dL compared to the control group, Δ%= -7.4 mg/dL. CONCLUSION: After three months of hydrogymnastics the IgA level did not show significant change on elderly women; However, positive improvement in percentage of change Δ% was found.
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Imunoglobulina A/sangue , Natação , Idoso , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Nefelometria e Turbidimetria , Condicionamento Físico Humano/métodosRESUMO
Bioelectrical impedance analysis (BIA) is a method used to estimate body composition, and it relies mainly on the body's water content. Insufficient body water can introduce bias to body composition scores. PURPOSE: To determine the effect of body weight loss elicited by passive dehydration on body composition scores, including phase angle (PhA). METHODS: Twenty-five euhydrated apparently healthy and physically active men's (age = 22.6 ± 3.3 yr.; body mass = 76.7 ± 15.9 kg; height = 172.0 ± 6.3 cm) body composition variables and PhA were measured before and after sitting quietly for 5 h in a controlled environment (26.6 ± 1.7 °C, 72 ± 4.9%RH). RESULTS: It was found that five hours of passive dehydration caused a loss in body weight (Δ = 0.76 ± 0.34 kg, p < 0.05) and a decrease in body fat estimation (Δ = 0.90 ± 0.87 kg, p < 0.001). Additionally, an increase in ECW (Δ = 0.12 ± 0.30 L, p < 0.021) and PhA (Δ = 0.10 ± 0.15°, p < 0.005) was observed. CONCLUSION: Body weight loss due to passive dehydration decreased BIA-derived fat mass, and increased extracellular water and PhA in physically active and apparently healthy men. Nonetheless, these changes had a negligible effect on the accuracy of the equipment, rendering them clinically insignificant.
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Composição Corporal , Água Corporal , Desidratação , Impedância Elétrica , Redução de Peso , Humanos , Masculino , Desidratação/fisiopatologia , Adulto , Redução de Peso/fisiologia , Adulto JovemRESUMO
The advancement of public services, including the increased accessibility of health services, has led to a rise in life expectancy globally. As a result, aging populations are becoming more prevalent, raising concerns about cognitive decline. Fortunately, non-pharmacological methods, such as physical exercise, have been shown to mitigate the effects of aging on the brain. In this perspective article, we examined meta-analyses on the impact of physical exercise on cognition in older adults. The results indicate that combined exercise (i.e., aerobic plus strength training), has a significant positive effect on overall cognition and executive function. However, we found a lack of scientific studies on this topic in Latin American and Caribbean countries. Therefore, there is a pressing need for research to identify the feasibility of physical exercise interventions to improve cognitive skills in older adults from these regions.
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BACKGROUND: Scarce evidence exists on barriers to physical activity in Mexican women. Despite evidence from other countries, no research has investigated the influence of the breast on PA in this population. OBJECTIVE: To determine the association between the breast and physical activity in Mexican women. DESIGN: Cross-sectional observational study. METHODS: Volunteers were 279 Mexican women from Veracruz, Durango, and Baja California states, who completed a paper survey of their demographics, brassiere characteristics, breast pain, and frequency and amounts of weekly physical activity. RESULTS: The first barrier to physical activity was time constraints, followed by breast-related issues. Breast pain was reported by 47.1% of women, and the breast as a barrier to physical activity participation was reported by 30.6%. Responses, such as "I am embarrassed by excessive breast movement" and "My breasts are too big" were the most frequently reported breast-related barriers to physical activity. Breast pain was associated with the menstrual cycle and exercise. Breast health knowledge and pain intensity were unrelated to moderate- and vigorous-intensity physical activity. The 36.4% and 6.7% of women did not meet weekly moderate- and vigorous-intensity physical activity guidelines, respectively. Weekly moderate- and vigorous-intensity physical activity was similar between women reporting breast pain and those who did not. CONCLUSIONS: Because the breast was the second most significant barrier to physical activity, it is imperative to increase breast health knowledge in Mexican women to reduce impediments to physical activity.
Perception of Mexican women regarding their breasts as a barrier to physical activityPhysical activity provides numerous health benefits, sometimes associated with reversing or delaying several diseases. However, barriers to increasing physical activity in women remain, as the breast is an anatomical aspect that is unique to women. Breast pain has been reported in more than 50% of women who perform physical exercise. Therefore, the study aimed to determine the associations between breast characteristics and barriers to physical activity in Mexican women. Two hundred and seventy-nine women from three Mexican states voluntarily participated in the study. They answered survey questions on the history of bra use, barriers to physical activity, and essential demographic characteristics. The main findings of this study were that issues related to the breasts were reported as the second barrier to physical activity participation. In addition, time constraints were reported as the main reason impeding physical activity participation. Public health initiatives should support attempts to increase breast satisfaction among women of all breast sizes to stimulate engagement in physical activity throughout their lives.
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Mastodinia , Feminino , Humanos , Estudos Transversais , México , Mama , Exercício FísicoRESUMO
Background: The COVID-19 pandemic affected older adults worldwide. Sedentary older adults experienced more severe adverse health effects due to their shelter-in-place. Physical activity was strongly recommended during periods of social distancing. The present study evaluated the impact of a virtually supervised exercise program on the physical fitness and mental health of Mexican older adults during the pandemic's lockdown. Methods: Participants were 44 older adults who were assigned to one of four physical fitness groups: a healthy control group (Ctrl-H, n = 15), a comorbidity control group (Ctrl-COM, n = 9), an exercise group without comorbidities (Exe-H, n = 11), and an exercise group with comorbidities (Exe-COM, n = 9). The participants engaged in a 60-min, virtually-supervised concurrent exercise session three times/week for 12 weeks. Fitness was measured using the online Senior Fitness Tests and the 4-m Gait Speed Test. Mental health was evaluated through virtual interviews using the Hamilton Depression Rating Scale, the Geriatric Depression Scale, and the Connor-Davidson Resilience Scale. Within-subject pre vs. post-intervention comparisons tested for significant differences, between-groups and over time. Results: Significant interactions were found in the scores of the Geriatric Depression Scale (p ≤ 0.0001; ηp2 = 0.35), the Hamilton Depression Scale (p ≤ 0.0001; ηp2 = 0.35), resilience scores (p ≤ 0.0001; ηp2 = 0.46), lower-body strength (p ≤ 0.0001; ηp2 = 0.32), timed up-and-go test (p = 0.018; ηp2 = 0.18), the 6MWT distance scores (p ≤ 0.0001; ηp2 = 0.39), and the 4-m gait speed test scores (p = 0.011; ηp2 = 0.20). Conclusion: A long-term virtually-supervised exercise program conducted during the COVID-19 lockdown period led to marked improvements in both the fitness and mental health of older Mexican adults. Comorbidities did not diminish these benefits. These findings provide empirical support for online exercise programs in the daily routines of older adults to make clinically meaningful improvements in both physical and mental well-being.
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COVID-19 , Comorbidade , Saúde Mental , Aptidão Física , Humanos , COVID-19/psicologia , Idoso , Masculino , Feminino , México , Exercício Físico/psicologia , Terapia por Exercício/métodos , Idoso de 80 Anos ou mais , SARS-CoV-2 , Pandemias , Pessoa de Meia-IdadeRESUMO
Purpose. To evaluate changes in walk test performance and blood pressure (BP) responses following a 12-week exercise-based outpatient cardiac rehabilitation (CR) program. Methods. Six-Minute Walk Test (6MWT) and resting systolic BP (SBP), diastolic BP (DBP), post-6MWT heart rate (HR), and post-6MWT BPs were measured before and after CR in 311 (237 men,74 women) patients. Using age as a covariate, 2 by 2 (Gender × Measurement) ANCOVAs were used to determine differences in 6MWT performance and hemodynamic variables. Results. After adjusting for age, men covered a greater 6MWT distance than women; pre-CR versus post-CR program values are as follows: men, 429.3 ± 94.6 versus 557.6 ± 90.7 m, P ≤ .001; women, 374.9 ± 100.7 versus 483.2 ± 82.9 m, P ≤ .001. Both genders reduced resting DBP following the CR program (men: 67.2 ± 9.8 vs 65.6 ± 8.5 mm Hg, P = .034; women: 69.2 ± 10.7 vs 65.0 ± 8.0 mm Hg, P = .001) and increased HR following the 6MWT after the CR program (men: 97.7 ± 16.8 vs 112.7 ± 21.3 bpm, P ≤ .001; women: 100.7 ± 20.8 vs 110.2 ± 22.0 bpm, P ≤ .001). Similarly, SBP increased immediately following the 6MWT (122.8 ± 18.5 vs 133.6 ± 20.7 mm Hg; P ≤ .001) in men but not in women. Conclusion. The present findings indicate similar relative improvements in 6MWT performance and BP responses in adherent men and women following an exercise-based CR program.
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Purpose: To determine the acute and chronic effects of exercise on Paraoxonase-1 (PON1) concentration and activity. Methods: A literature search was performed using 16 electronic databases. Effect sizes (ES) were computed and two-tailed α values < .05 and non-overlapping 95% confidence intervals (95%CI) were considered statistically significant. Heterogeneity, inconsistency (I2), and small-study effects using the LFK index were examined. Results: Eighteen studies (n = 377 participants) met the criteria for inclusion. The acute effects of exercise on PON1 concentration were trivial and non-significant (ES = -.03, 95%CI = -.39 to .34, p > .05), heterogeneous (p = .05), moderately inconsistent (I2 = 48%), with minor asymmetry (LFK index = 1.34). The chronic effects of exercise on PON1 concentration were also trivial and non-significant (ES = -.04, 95%CI = -.53 to.45, p > .05), homogenous (p = .65), displayed low inconsistency (I2 = 0%), and minor asymmetry (LFK index = -1.14). The acute effects of exercise on PON1 activity were trivial and non-significant (ES = .11, 95%CI = -.02 to.24, p > .05), homogenous (p = .85), showed low inconsistency (I2 = 0%), and no asymmetry (LFK index = .82). The chronic effects of exercise on PON1 activity were trivial and non-significant (ES = .31, 95%CI = -.03 to.65, p > .05), homogenous (p = .17), moderately inconsistent (I2 = 36%), with no asymmetry (LFK index = .60). Conclusion: Acute and chronic exercise training, overall, exerted a trivial effect on PON1 concentration and activity.
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Arildialquilfosfatase , Exercício Físico , Arildialquilfosfatase/metabolismo , Arildialquilfosfatase/fisiologia , Exercício Físico/fisiologia , HumanosRESUMO
Since 2020, the world has been suffering from a pandemic that has affected thousands of people regardless of socio-economic conditions, forcing the population to adopt different strategies to prevent and control the advance of the disease, one of which is social distancing. Even though social distancing is a safe strategy to reduce the spread of COVID-19, it is also the cause of a rising sedentary behavior. This behavior develops an excess of fat tissue that leads to metabolic and inflammatory disruption related to chronic diseases and mental health disorders, such as anxiety, depression, and sleep issues. Furthermore, the adoption of dietary patterns involving the consumption of ultra-processed foods, higher in fats and sugars, and the reduction of fresh and healthy foods may play a role in the progress of the disease. In this perspective, we will discuss how an unhealthy diet can affect brain function and, consequently, be a risk factor for mental health diseases.
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The study aimed to analyze the relationship between commitment to the team and team resilience factors (characteristics of resilience and vulnerability under pressure), and to examine whether the task and social intra-group conflict act as mediators between commitment to the team and team resilience factors. One hundred seventy (170) male soccer players (16-38 years; M = 18.35; SD = 4.72) of the national teams of Argentina, Costa Rica, and Mexico participated in the study. The path analytic model was used to test mediating pathways. First, the results revealed that commitment to the team was positively related to characteristics of resilience and negatively to vulnerability under pressure. Second, bootstrap mediation analysis showed that athletes' perceptions of the task and social intra-group conflict mediated the association between their perception of commitment to the team and team resilience factors. Findings provide initial evidence for a link between commitment to the team and team resilience in national teams and also suggest that intra-group conflict can improve the association between commitment to the team and team resilience. Therefore, the main conclusion of this study is that practioners should promote players' commitment to the team and avoid intra-group conflicts within teams to have a resilient team that copes with problems more easily.
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This study aimed to determine the body composition profile of candidates applying for a Physical Education and Sports major. 327 young adults (F: 87, M: 240) participated in this cross-sectional study. Nutritional status and body composition analysis were performed, and the profiles were generated using an unsupervised machine learning algorithm. Body mass index (BMI), percentage of fat mass (%FM), percentage of muscle mass (%MM), metabolic age (MA), basal metabolic rate (BMR), and visceral fat level (VFL) were used as input variables. BMI values were normal-weight although VFL was significantly higher in men (<0.001; η2 = 0.104). MA was positively correlated with BMR (0.81 [0.77, 0.85]; p < 0.01), BMI (0.87 [0.84, 0.90]; p < 0.01), and VFL (0.77 [0.72, 0.81]; p < 0.01). The hierarchical clustering analysis revealed two significantly different age-independent profiles: Cluster 1 (n = 265), applicants of both sexes that were shorter, lighter, with lower adiposity and higher lean mass; and, Cluster 2 (n = 62), a group of overweight male applicants with higher VFL, taller, with lower %MM and estimated energy expended at rest. We identified two profiles that might help universities, counselors and teachers/lecturers to identify applicants in which is necessary to increase physical activity levels and improve dietary habits.
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Composição Corporal , Educação Física e Treinamento , Adulto Jovem , Feminino , Masculino , Humanos , Estudos Transversais , Composição Corporal/fisiologia , Índice de Massa Corporal , Sobrepeso/epidemiologiaRESUMO
BACKGROUND/OBJECTIVE: The quarantine caused by the COVID-19 pandemic increased sedentary behavior, psychological stress, and sleep disturbances in the population favoring the installation of alterations in the cardiovascular system. In this sense, physical exercise has widely been suggested as an efficient treatment to improve health. The current study determined the impact of short-term high-intensity circuit training (HICT) on resting heart rate variability (HRV) in adults. METHODS: Nine healthy participants (age: 31.9 ± 4.4 yr.) performed 36 HICT sessions (3 times per day; 3 days per week) and four participants (age: 29.5 ± 1.7 yr.) were assigned to a control group. The HICT consisted of 12 min of whole-body exercises performed during a workout. Twenty-four hours before and after the exercise program, HRV parameters were recorded. RESULTS: The heart rate exercise during the last session trended to be lower when compared with the first HICT session (p = 0.07, d = 0.39, 95% CI = -13.50, 0.72). The interval training did not modify the HRV time (Mean NN, SDNN, RMSSD, NN50, pNN50) and frequency (LF, HF, LF/HF ratio, total power) domain parameters. CONCLUSION: Thirty-six HICT sessions did not provide enough stimuli to modify the resting HRV in adults during social isolation elicited by the COVID-19 pandemic. However, the data suggested that exercise protocol did not induce cardio-vagal adaptations.
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COVID-19 , Exercícios em Circuitos , Adulto , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Humanos , PandemiasRESUMO
Background: Human brain function declines with aging. In this sense, exercise-based interventions has a promising effect on brain plasticity for older adults. Serum brain-derived neurotrophic factor (BDNF) is a positive biomarker for brain neuroplasticity in healthy older adults also modified by exercise training. Selected features of the exercise prescription for improving brain health are missing; therefore, the aim of this study was to determine the effects of concurrent exercise training frequency on serum BDNF levels in healthy older adults. Methods: Nineteen volunteers (age: 65 ± 4 year; body mass index: 28.0 ± 4.5 kg/m2) completed either a three times/week (3-t/w) (n = 8) or five times/week (5-t/w) (n = 11) concurrent exercise program. The exercise program lasted 11 weeks and all exercise sessions were performed for 50 min at moderate intensity. Serum BDNF, body composition, cardiovascular, and physical fitness variables were assessed before and after the exercise training program. Results: Regardless of the group, the serum BDNF increased following the intervention (p < 0.001), and there were no significant group (p = 0.827) or interaction (p = 0.063) effects. The maximal oxygen consumption (VO2max) increased regardless of the group (p = 0.007), with a non-significant group (p = 0.722) or interaction (p = 0.223) effects. Upper- and lower-body strength increased in both groups (p = 0.003); however, there was no effect of the training frequency (p = 0.53). For the skeletal muscle mass, there was a trend in the interaction effect (p = 0.053). Finally, the body fat percentage was unchanged. Conclusion: Eleven weeks of combined exercise training increased serum BDNF levels in healthy older adults, a response independent of the training frequency. The overall fitness level improved similarly in both exercise groups. These data reveal that a minimal dosage of concurrent exercise enhance functional capacity and a brain health biomarker in older adults.
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The consumption of sugar-sweetened beverages has been associated with the onset of cardiometabolic diseases. The aim of this study was to describe consumption patterns of sugar-sweetened and dairy beverages and to evaluate their correlation with the body mass index in children residing at the Mexico−USA border. A total of 722 (370 girls, 352 boys) elementary school children aged 9 to 12 years from Tijuana, Mexico, participated in the study. Anthropometric measures were recorded, and a beverage intake questionnaire was completed by the children's parents. Significant age by sex interactions were found on body mass index Z-scores (p < 0.01). Boys showed higher sugar intake (p < 0.05) and total relative energy consumption from sugar (p < 0.05) than girls. The energy consumption from sugar-sweetened and dairy beverages was similar between sexes (p > 0.05). Sugar intake from beverages was higher than the limit recommended by the World Health Organization in boys (66%) and girls (44%). A high frequency of consumption of sugar-sweetened beverages and similar intake of dairy beverages were found in children from the Mexico−USA border. The high consumption of sugar exceeds international recommendations and should be carefully monitored.