Prediction of fat-free mass from body surface area in young basketball players.

BACKGROUND: Fat Free Mass (FFM) is an important and essential indicator in various sports populations, since greater muscle and bone mass generates greater strength, endurance and speed in athletes. OBJECTIVE: The purpose of the study was to validate Body Surface Area (BSA) as an anthropometric indicator to estimate FFM in young basketball players. METHODS: A descriptive cross-sectional study was carried out in 105 male basketball players of the Brazilian Basketball Confederation of Sao Paulo (Campinas), Brazil. The age range was 11 to 15 years. Weight and height were evaluated. BSA, body mass index (BMI) and maturity status (MS) were calculated. Total body scanning was performed by dual X-ray absorptiometry (DXA). The components were extracted: Fat mass (FM), Fat free mass (FFM), percentage of fat mass (%FM) and bone mass (BM). The data were analyzed using the correlation coefficient of concordance (CCC) in terms of precision and accuracy. RESULTS: Three regression equations were generated: equation 1 had age and body weight as predictors [FFM= -30.059+(2.926*age)+(0.625*Weight)] (R2 = 92%, precision = 0.96 and accuracy = 0.99), equation 2 used age and BSA [FFM=-45.719+(1.934*age)+(39.388*BSA)] (R2 = 94%, precision = 0.97 and accuracy = 0.99) and equation 3 was based on APHV and BSA [FFM=-15.284+(1.765*APHV)+(37.610*(BSA)] (R2 = 94%, precision = 0.96 and accuracy = 0.99). CONCLUSIONS: The results suggest the use of anthropometric equation using decimal age and BSA to estimate FFM in young basketball players. This new method developed can be used to design, evaluate and control training programs and monitor the weight status of athletes.

Tracking de 10 anos da aptidão física e capacidade funcional de mulheres adultas praticantes de atividade física / 10-Year tracking of fitness and functional capacity of adult women practicing physical activity of physical activity

Contexto e objetivo: Diversos benefícios são advindos da prática da atividade física durante o envelhecimento, porém poucos são os achados que apresentem os dados ao longo do tempo. Assim, o objetivo deste estudo foi verificar a estabilidade das variáveis da aptidão física e capacidade funcional de mulheres adultas praticantes de atividade física em um período de 10 anos. Desenho e local: Estudo longitudinal com mulheres de São Caetano do Sul. Métodos: A amostra foi composta por 157 mulheres com idade entre 45 e 86 anos (65,7 ± 6,7), analisadas em quatro intervalos de tempo: baseline, 6, 8 e 10 anos, todas praticantes de atividade física. A avaliação incluiu variáveis antropométricas, neuromotoras e de capacidade funcional. A análise estatística utilizada foi o teste t de Student, correlação de Spearman Rho e delta percentual. O nível de significância adotado foi de P < 0,01. Resultados: Os resultados apresentaram correlações de estabilidade alta e significante (rho = 0,64 a 0,87) nos três grupos nas variáveis índice de massa corporal, adiposidade, força de membros superiores, flexibilidade e agilidade. O acompanhamento de 6 a 10 anos evidenciou diferenças significantes de força de membros superiores, inferiores, agilidade e equilíbrio, sendo expressa pela redução da força de membros superiores de 8% a 13%, força de membros inferiores de 18% a 21%, agilidade de 18% a 19% e equilíbrio de 28% a 34%. Conclusão: Houve estabilidade das variáveis antropométricas, neuromotoras, capacidade funcional e equilíbrio de mulheres adultas praticantes de atividade física, mesmo apresentando redução significativa nas variáveis citadas anteriormente.

Association between school environment with sedentary behavior and physical activity intensity in children.

We examined the association between indicators of the school environment with sedentary behavior and different intensities of physical activity in children. The study that included 515 children (265 boys) aged 9-11 years old from public and private schools in the city of São Caetano do Sul. Sedentary behavior and different intensities of physical activity were evaluated with an accelerometer. Inside school environment (policies, supervision committee, extracurricular activities, breaks, and access to school facilities) was evaluated using a questionnaire. Policies and practice (ß: 8.49; 95% CI: 3.62-13.36), supervision committee (5.42; 0.64-10.19), inter-school competitions (2.40, 2.25-2.55), breaks of 15-29 min/day (6.87; 2.20-10.75), and outdoor sports field (5.40; 0.37-10.44), were positively associated with moderate-to-vigorous-intensity physical activity. Furthermore, crossing guards (7.65; 3.00-12.30) were positively associated with moderate-to-vigorous-intensity physical activity. We concluded that an association was found between school environment indicators with higher levels of physical activity and greater odds of meeting physical activity guidelines.

Positive association of lean mass and negative association of protein intake on bone mass and bone geometry of adolescent soccer players.

OBJECTIVE: The aim of this study was to evaluate the association of food consumption and body composition on bone parameters in adolescent soccer players. METHODS: There were 148 male soccer players 12 to 18 y who participated in the study. Body composition was assessed by dual energy x-ray absorptiometry, comprising bone mineral density (BMD) and bone mineral content (BMC) of total body without head (TBLH), lumbar spine (L1-L4), and right femoral neck (RFN). The bone geometry variables measured were femoral strength index (FSI), buckling ratio (BR), section modulus (Z), cross-sectional moment of inertia (CSMI), and cross-sectional area (CSA). Food intake was analyzed using the 24-h food recall. Somatic maturation was estimated by the peak height velocity equation. For the statistical analysis, the stepwise multiple linear regression was used, with P < 0.05. RESULTS: Regarding food consumption, there was a high protein intake and low calcium intake. Lean mass was a predictor of BMC of TBLH (R2 = 0.524), L1-L4 (R2 = 0.492), and RFN (R2 = 0.405); BMD of L1-L4 (R2 = 0.407) and RFN (R2 = 0.27); Z (R2 = 0.683), CSMI (R2 = 0.630), and CSA (R2 = 0.640). There was a negative correlation between protein intake with bone mass and bone geometry parameters. CONCLUSION: In adolescent soccer players, lean mass was a predictor of bone parameters, and high protein intake was negatively associated with bone mass and geometry.

Physical activity level measured by accelerometry and physical fitness of schoolchildren / Nível de atividade física mensurada por acelerometria e aptidão física de escolares

Abstract Objective: To describe and compare physical fitness variables according to compliance with the recommendations of physical activity, measured by accelerometry. Methods: The sample gathered 120 students, 57 boys and 63 girls aged 9 to 11 years. The variables analyzed were: weight, stature, BMI, skinfolds, waist circumference, agility, flexibility, speed and strength of upper and lower limbs, and abdominal strength. Physical activity was measured objectively using an accelerometer. The students were divided into two groups: "complies with recommendations" (≥60min/day) and "does not comply with recommendations" (<60min/day). To verify the normality of the data, the Kolmogorov-Smirnov test was used. The mean values of students who do or do not comply with the physical activity recommendation were compared using Student's t and U-Mann Whitney tests. The level of significance was set at p<0.05. Results: The students who followed the recommendation showed significantly lower values compared to those who did not for adiposity (sum of 7 skinfolds); body weight; body mass index (BMI) and abdominal strength. No significant differences were found in the variables of speed and agility, and the upper limbs' strength was greater in subjects who did not comply with recommendations. Conclusions: Students who complied with physical activity recommendations had better body composition and more abdominal strength than those who did not.

RESUMO Objetivo: Descrever e comparar as variáveis da aptidão física de acordo com o cumprimento da recomendação de atividade física, medida por acelerometria. Métodos: A amostra foi composta de 120 escolares, sendo 57 meninos e 63 meninas, de 9 a 11 anos de idade. As variáveis analisadas foram: peso, estatura, índice de massa corpórea (IMC), dobras cutâneas, circunferências, agilidade, flexibilidade, velocidade e força de membros superiores, inferiores e abdominal. A atividade física foi mensurada de forma objetiva por meio de acelerômetro. Os escolares foram divididos em dois grupos: "cumpre a recomendação" (≥60min/dia) e "não cumpre a recomendação" (<60min/dia). Para verificar a normalidade dos dados, foi utilizado o teste de Kolmogorov-Smirnov. A comparação dos valores médios dos escolares que cumprem ou não a recomendação de atividade física foi feita pelos testes t de Student e U de Mann-Whitney. O nível de significância adotado foi de p<0,05. Resultados: Os escolares que cumpriram a recomendação, comparados com os que não cumpriram, apresentaram valores significativamente menores para adiposidade (somatória das sete dobras cutâneas), peso corporal, IMC e força abdominal. Não foram encontradas diferenças significativas nas variáveis de velocidade e agilidade; quanto à força de membros superiores (MMSS), constatou-se que ela foi maior em quem não cumpriu a recomendação. Conclusões: Crianças que cumpriram a recomendação de atividade física apresentaram melhor composição corporal e força abdominal que as crianças que não cumpriram.

Physical activity level measured by accelerometry and physical fitness of schoolchildren.

OBJECTIVE: To describe and compare physical fitness variables according to compliance with the recommendations of physical activity, measured by accelerometry. METHODS: The sample gathered 120 students, 57 boys and 63 girls aged 9 to 11 years. The variables analyzed were: weight, stature, BMI, skinfolds, waist circumference, agility, flexibility, speed and strength of upper and lower limbs, and abdominal strength. Physical activity was measured objectively using an accelerometer. The students were divided into two groups: "complies with recommendations" (≥60min/day) and "does not comply with recommendations" (<60min/day). To verify the normality of the data, the Kolmogorov-Smirnov test was used. The mean values of students who do or do not comply with the physical activity recommendation were compared using Student's t and U-Mann Whitney tests. The level of significance was set at p<0.05. RESULTS: The students who followed the recommendation showed significantly lower values compared to those who did not for adiposity (sum of 7 skinfolds); body weight; body mass index (BMI) and abdominal strength. No significant differences were found in the variables of speed and agility, and the upper limbs' strength was greater in subjects who did not comply with recommendations. CONCLUSIONS: Students who complied with physical activity recommendations had better body composition and more abdominal strength than those who did not.

Gordura corporal, índice de massa corporal e intensidade da atividade física de acordo com transporte ativo e a prática esportiva em escolares. Um estudo transversal / Body fat, body mass index and physical activity intensity according to active transport and sports practice in schoolchildren. A cross-sectional study

Contexto: A obesidade infantil ocasiona diversas doenças e uma das formas para combatê-la é a atividade física, que exerce um papel fundamental. Objetivo: Comparar as diferentes intensidades da atividade física mensurada objetivamente de acordo com o transporte ativo, a prática de esportes e as atividades físicas estruturadas e seu impacto na gordura corporal e índice de massa corporal (IMC) em escolares. Desenho e local: Estudo transversal de amostra por critério de conveniência, realizado em São Caetano do Sul pelo Centro de Estudos do Laboratório de Aptidão Física de São Caetano do Sul (CELAFISCS). Métodos: Foram avaliadas um total de 584 crianças (277 meninos) que atenderam aos critérios de inclusão. A amostra foi dividida em grupos segundo o transporte (ativo e passivo) e a prática esportiva (sim e não). Para análise estatística foi utilizado o teste t Student e o teste U de Mann-Whitney. Para o ajuste das variáveis foi utilizada a análise de covariância (ANCOVA). Resultados: Os meninos demonstraram que, independentemente do tempo de transporte, há efeito do tipo do transporte sobre a atividade física (AF) durante a semana, de intensidade moderada, moderada-vigorosa, AF durante o final de semana de intensidade moderada, moderada-vigorosa e vigorosa. As meninas demonstraram efeito do tipo de transporte sobre a AF durante a semana na AF de intensidade moderada e de intensidade moderada-vigorosa. A gordura corporal e o IMC não apresentaram diferenças entre os grupos. As práticas esportivas não tiveram diferenças significativas em nenhuma das variáveis. Conclusões: O transporte ativo atingiu os níveis de intensidade moderada, moderada-vigorosa durante a semana, tanto no masculino como no feminino. No final de semana, além dessas, a intensidade vigorosa foi encontrada nos meninos.