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1.
J Sports Sci ; 41(9): 895-902, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37599614

RESUMO

Estimate the shape and number of cardiorespiratory fitness (CRF) trajectories from childhood to adolescence; and verify whether CRF trajectory membership can be predicted by sex, biological maturation, body weight, body composition and physical activity (PA) in childhood. Data from QUALITY were used. Participants attended baseline (8-10 y old, n = 630) and follow-ups 2 years (n = 564) and 7 years (n = 359) after baseline. Group-based trajectory analysis for relative peak oxygen consumption (VO2peak, ml·kg-1·min-1) was performed. A multinomial logistic regression model was used to estimate the associations between baseline predictors and trajectory membership. Mean age of the 454 participants was 9.7 ± 0.9 years at baseline. Three distinct VO2peak trajectories were identified and all tended to decrease. They were labelled according to the starting point and slope. High-Decreasers were mostly boys, had lower body weight and fat-free mass index and higher PA levels at baseline (p < 0.05). Female sex and higher weight were associated with higher odds of being classified in the Low-Decreaser trajectory (OR = 74.03, 95%CI = 27.06-202.54; OR = 1.48, 95%CI = 1.36-1.60). Those with higher PA were less likely to be Low-Decreasers (OR = 0.96, 95%CI = 0.94-0.97). Sex, body weight and PA in childhood are important influencing factors of VO2peak (ml·kg-1·min-1) trajectories across adolescence.

2.
Int J Sports Med ; 41(9): 610-615, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32353880

RESUMO

The phase angle is used to evaluate nutritional status and is an indicator of cellular health. Cardiorespiratory fitness and body composition are strong indicators of health during adolescence. We aimed to evaluate if body composition and cardiorespiratory fitness have an association with phase angle among adolescents. 203 girls and 220 boys (12.8±1.3 years) were evaluated. Peak height velocity, percentage fat mass, fat-free mass, cardiorespiratory fitness, and phase angle measurements were collected. Linear regression adjusted by peak height velocity was used to verify if predictor variables were associated with phase angle among adolescents. Phase angle showed correlation with fat-free mass (girls: r=0.42 and boys: r=0.37); with percent fat mass (girls: r=0.23); and with cardiorespiratory fitness (boys: r=0.19). Linear regression showed that percentage fat mass (in girls) and cardiorespiratory fitness (in boys) had an effect of 11 and 17% in phase angle, respectively, while fat-free mass had an effect of 22 and 26% in phase angle for girls and boys, respectively. Changes in phase angle seem to be more associated with the percentage fat mass in girls, cardiorespiratory fitness in boys, and fat-free mass in both when controlled by peak height velocity.


Assuntos
Composição Corporal/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Estado Nutricional/fisiologia , Adolescente , Distribuição da Gordura Corporal , Índice de Massa Corporal , Criança , Feminino , Humanos , Masculino , Avaliação Nutricional , Dobras Cutâneas
3.
Hum Mov Sci ; 87: 103040, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36495687

RESUMO

PURPOSE: To estimate the shape and number of mechanical efficiency (ME) trajectories from childhood to adolescence; and verify whether ME trajectory membership can be predicted by sex, biological maturation, body weight, body composition and physical activity (PA) in childhood. METHODS: Data from QUALITY, an ongoing cohort study on the natural history of obesity, were used. Participants attended a baseline visit (8-10 years, n = 630) and follow-up visits two years (n = 564), and seven years (n = 377) later. ME was assessed by an incremental cycling test at 50w (ME50w, %) and at VO2peak (MEVO2peak, %). Group-based trajectory analysis for ME and a logistic regression were performed. RESULTS: Mean age of the 454 participants (boys = 54%) was 9.7 ± 0.9 years at baseline. Two distinct ME50w trajectories were identified and all tended to decrease. No distinct trajectories emerged for MEVO2peak; average MEVO2peak increased over time. Thus, the difference between MEVO2peak (∆) at baseline and follow-up was calculated for correlation analysis. Trajectory groups were labeled "Low-Decreaser" and "High-Decreaser" (Reference) for ME50w, describing the starting point and slope. High-Decreasers were mostly prepubertal girls, had lower body weight and fat free mass index, lower PA and lower VO2peak at baseline (χ2or t-test, p < 0.05). Girls were less likely to be Low-Decreasers (OR = 0.56, 95%CI = 0.42-0.74), while having overweight/obesity predicted a greater likelihood of classification in the Low-Decreaser trajectory (OR = 2.38, 95%CI = 1.16-4.88). Those with higher PA were more likely to be Low-Decreasers (OR = 1.02, 95%CI = 1.01-1.04). Finally, concerning MEVO2peak, sex, biological maturation, body weight, zBMI, fat free mass index, PA and VO2peak were positively correlated with ∆ MEVO2peak. CONCLUSIONS: We found evidence that excess weight at baseline predicts low levels of ME in childhood and adolescence. Additionally, higher PA at baseline is not related to higher ME50w levels. More research is needed to identify different approaches to explore this measure in transition to adulthood.


Assuntos
Obesidade , Masculino , Feminino , Humanos , Adolescente , Criança , Estudos de Coortes , Índice de Massa Corporal , Peso Corporal , Estudos Longitudinais
4.
Am J Lifestyle Med ; 16(5): 633-640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072691

RESUMO

The main aim was to verify in a group of adolescent girls undergoing a school-based intervention if the number of years of participation in the intervention is related to healthy lifestyle habits, body weight status, and perceived health. Cross-sectional analysis of the FitSpirit data was performed. Body mass index, lifestyle variables, and perceived health were collected through an online questionnaire. Chi-square test, Fisher's test, and ANOVA were performed. Mean age of the 272 girls was 14.7 ± 1.5 years. Higher percentage of girls with 3 or more years of participation met the recommendations for physical activity (PA) and sleep duration (P < .05). Girls who participated ≥3 years showed higher levels of moderate-to-vigorous PA than girls with 1 and 2 years of participation (P < .01). No differences were found between the number of years of participation and body mass index, screen time, fruit/vegetable consumption, or perceived health. A healthier body weight status and following recommendations for healthier habits (PA, screen time, sleep, fruit/vegetable consumption) were related to better perceived health (P < .05). Girls with more years in FitSpirit had healthier lifestyle habits (PA and sleep) compared to those with fewer years. A healthier body weight status and meeting healthy lifestyle recommendations were related to better perceived health.

5.
Artigo em Inglês | MEDLINE | ID: mdl-27164119

RESUMO

OBJECTIVE: To determine the accuracy of two international Body Mass Index (BMI) cut-offs for classifying obesity compared to the percentage of fat mass (%FM) assessed by Dual-Energy X-ray Absorptiometry (DXA) in a Chilean sample of children and adolescents; MATERIAL AND METHODS: The subjects studied included 280 children and adolescents (125 girls and 155 boys) aged 8 to 17 years. Weight and height were measured. The BMI was calculated. Two international references (IOFT and WHO) were used as cut-off points. The %FM was assessed by DXA. The receiver operating characteristic (ROC) curve was used to assess the performance of BMI in detecting obesity on the basis of %FM; RESULTS: A high correlation was observed between the %FM measured by the DXA and the Z-scores of IOTF and WHO scores in the Chilean adolescents separated by sex (r = 0.78-0.80). Differences occurred in both references (IOFT and WHO) in relation to the criteria (p < 0.001). Both references demonstrated a good ability to predict sensitivity (between 84% and 93%) and specificity (between 83% and 88%) in both sexes of children and adolescents; CONCLUSIONS: A high correlation was observed between the Z-score of the BMI with the percentage of fat determined by the DXA. Despite this, the classifications using the different BMI cut-off points showed discrepancies. This suggests that the cut-off points selected to predict obesity in this sample should be viewed with caution.


Assuntos
Absorciometria de Fóton , Índice de Massa Corporal , Obesidade/diagnóstico , Adolescente , Composição Corporal , Peso Corporal , Criança , Chile , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Prevalência , Padrões de Referência , Reprodutibilidade dos Testes , Fatores Sexuais
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