Jose Oliveira-Santos

Muscular fitness and metabolic and inflammatory biomarkers in adolescents: Results from LabMed Physical Activity Study

This study aimed to evaluate the associations between muscular fitness and inflammatory biomarkers and to investigate the relationship between muscular fitness and selected clustered inflammatory biomarkers in adolescents. This is a cross‐sectional analysis with 529 adolescents (267 girls) aged 12‐18 years. Handgrip strength and standing long jump tests assessed MF. Continuous scores of clustered inflammatory biomarkers (sum of Z‐scores of C‐reactive protein [CRP], C3, C4, fibrinogen, and leptin); metabolic risk factor (MRF) score (sum of Z‐scores of SBP, triglycerides, ratio total cholesterol [TC]/HDL, HOMA‐IR, and waist circumference [WC]) were computed. Regression analyses showed an inverse association between muscular fitness score (β=−.204; P<.021) and clustered score of inflammatory biomarkers, adjusted for age, sex, pubertal stage, socioeconomic status, adherence to the Mediterranean diet, cardiorespiratory fitness (CRF), MRF score, and body fat. Analysis of covariance showed that adolescents with an adverse inflammatory profile with low levels of muscular fitness exhibit the poorest MRF score (F3,525=6.461; P<.001), adjusted for age, sex, pubertal stage, socioeconomic status, adherence to the Mediterranean diet, CRF, and body fatness. The inflammatory state seems to explain a significant part of the highest MRF score and in adolescents with high inflammatory status and low muscular strength.

Cardiorespiratory Fitness and Blood Pressure: A Longitudinal Analysis

Objectives To examine the association between cardiorespiratory fitness and cardiovascular indices 2 years later, and to determine whether changes in cardiorespiratory fitness are associated with cardiovascular indices at a 2‐year follow‐up in adolescents. Study design The sample comprised 734 adolescents (349 girls) aged 12‐18 years followed for 3 years from the LabMed Physical Activity Study. Cardiorespiratory fitness was assessed by the 20‐meter shuttle run test. Height, weight, waist circumference, and resting blood pressure (BP) were measured according to standard procedures. Results Regression analyses showed a significant inverse association between cardiorespiratory fitness at baseline and systolic BP (B = −0.126; P = .047) and rate pressure product (B = −29.94; P = .016), at follow‐up after adjustments for age, sex, height, pubertal stage, socioeconomic status, and waist circumference. Significant differences were found between cardiorespiratory fitness groups (fit vs unfit) at baseline and systolic BP and rate pressure product at follow‐up (P < .05 for all). Analysis of covariance showed a significant association between cardiorespiratory fitness changes and systolic BP (P = .024) and rate pressure product (P = .014), after adjustment for age, sex, height, pubertal status, socioeconomic status, and waist circumference. Conclusions Changes in cardiorespiratory fitness during adolescence were associated with cardiovascular indices over a 2‐year period. Adolescents with persistently low levels of cardiorespiratory fitness exhibited the highest levels of systolic BP and rate pressure product.

Low-grade inflammation and muscular fitness on insulin resistance in adolescents: Results from LabMed Physical Activity Study

Low muscular fitness (MF) and low‐grade inflammation has been linked to insulin resistance (IR).

Muscular fitness, Southern European Atlantic Diet and inflammation in adolescents. Azorean Physical Activity and Health Study II

Abstract High muscular fitness (MF) and high adherence to the Southern European Atlantic Diet (the SEADiet) have been associated with several positive metabolic outcomes. The purpose of the present study was two-fold: (i) to explore the independent associations between MF and C-reactive protein (CRP) levels; and (ii) to investigate the combined impact of MF and SEADiet on the CRP levels in a sample of adolescents. A cross-sectional school-based study was conducted on 463 adolescents (272 girls) aged 15–18 years, from the Portuguese Azorean Archipelago. Anthropometric indicators (stature, body mass, waist circumference (WC)) were measured by standardized protocols and pubertal stages were assessed by Tanner criteria. Blood samples were taken after an overnight fast. MF was assessed by the curl-up and push-up tests (from the Fitnessgram test battery). Adherence to the SEADiet was assessed with a semi-quantitative food frequency questionnaire. Linear regression models showed that MF was inversely associated with hs-CRP (unstandardized B = −0.127; p < .009), after adjustments for age, sex, and pubertal stage, adherence of SEADiet, total energy intake and low-energy reporter and WC. Analysis of covariance (ANCOVA) showed a significant difference between the low adherence of SEADiet with low MF group and those with a high adherence of SEADiet and high MF (p < .05) (F(5, 453) = 2.238, p = .040). Our results showed that MF is inversely associated with hs-CRP. In addition, the adolescents with Low adherence of SEADiet/Low MF group had high levels of hs-CRP compared those who with high adherence of SEADiet/high MF group.

Serum adiponectin levels and cardiorespiratory fitness in nonoverweight and overweight Portuguese adolescents: The LabMed Physical Activity Study

PURPOSE This study examined the independent associations between cardiorespiratory fitness and circulating adiponectin concentration in adolescents, controlling for several potential covariates. METHODS This is a cross-sectional study in Portuguese adolescents. A sample of 529 (267 girls) aged 12-18 years were included and categorized as overweight and nonoverweight. Cardiorespiratory fitness was assessed by 20 meters shuttle run test. We measured serum adiponectin, high-sensitivity C-reactive protein, fasting glucose, insulin and HDL-cholesterol. RESULTS After adjustment for age, sex, pubertal stage, adherence to the Mediterranean diet, socioeconomic status, body fat percentage, insulin resistance, HDL-cholesterol and C-reactive protein, regression analysis showed a significant inverse association between adiponectin and cardiorespiratory fitness in nonoverweight participants (B=-0.359; p < .042). Analysis of covariance showed a significant difference between the highest cardiorespiratory fitness Healthy zone (above healthy zone) and the Under and the Healthy cardiorespiratory fitness zones in nonoverweight adolescents (p = .03) (F (2, 339) = 3.156, p < .001). CONCLUSION Paradoxically, serum adiponectin levels are inversely associated with cardiorespiratory fitness in nonoverweight, but not in overweight adolescents. In nonoverweight adolescents, those with highest levels of cardiorespiratory fitness (above healthy zone) presented lower levels of adiponectin compared with those in Under and Healthy cardiorespiratory fitness zones.

Association between Leptin, Adiponectin, and Leptin/Adiponectin Ratio with Clustered Metabolic Risk Factors in Portuguese Adolescents: The LabMed Physical Activity Study

Introduction: Circulating leptin and adiponectin levels have been associated with impaired vascular function, insulin resistance, and acute cardiovascular evens. This study aimed to evaluate the associations of leptin, adiponectin, and the leptin/adiponectin (L/A) ratio with a clustering of metabolic risk factors (MRF) in adolescents aged 12-18 years. Methods: This is a cross-sectional analysis with 529 Portuguese adolescents aged 12-18 years. Blood samples were taken to analyze total cholesterol (TC) and high-density lipoprotein (HDL) cholesterol (HDL-c), triglycerides glucose, insulin, leptin, and adiponectin levels. A continuous variable of clustered MRF score (sum of Z-scores of body fat percentage, systolic blood pressure, ratio TC/HDL, triglycerides, homeostatic model assessment insulin resistance, and cardiorespiratory fitness*[-1]) was computed. Results: Regression analyses showed that adiponectin was a significant and negative predictor of MRF score (boys: β = -0.199; p < 0.001; girls: β = -0.200; p < 0.001); whereas leptin was a significant positive predictor of MRF score (boys: β = 0.553; p < 0.001; girls: β = 0.399; p < 0.001). The L/A ratio was also a significant positive predictor of MRF score in both sexes (boys: β = 0.593; p < 0.001; girls: β = 0.461; p < 0.001), after adjustments for age, pubertal stage, adherence to the Mediterranean diet, and socioeconomic status. In addition, adiponectin, leptin, and L/A ratio were accurate to predict MRF among adolescents, but L/A ratio showed the highest area under receiver operating characteristic curve. Conclusion: Leptin, adiponectin, and L/A ratio are associated with the clustering of MRF in adolescents after adjustments for age, sex, pubertal stage, adherence to the Mediterranean diet, and socioeconomic status. L/A ratio was more strongly associated with MRF score than adiponectin or leptin.

Longitudinal associations between motor competence and different physical activity intensities: LabMed physical activity study

ABSTRACT An appropriated level of motor competence is essential for children´s healthy growth and development and a key factor in the promotion of lifelong active lifestyles and health. The purpose of this study was to examine associations between motor competence and different physical activity intensities (light, moderate, moderate-to-vigorous and vigorous physical activity), as well as total physical activity, over a two-year period, in adolescents. The sample comprised of 103 adolescents (13.49 ± 0.87 years, 53 girls), from the north of Portugal. Motor competence was evaluated with the body coordination test, Körperkoordination-Test-für-Kinder. Physical activity was objectively assessed with GT1M accelerometers (ActiGraph, Pensacola, FL, USA). Physical activity variables were expressed as proportions of accelerometer wear time. Regression analyses showed positive longitudinal associations between motor competence at baseline and moderate physical activity (B = 0.0033, p = 0.018), moderate-to-vigorous physical activity (B = 0.0052, p = 0.024) and total physical activity (B = 0.067, p = 0.040) at follow up, after adjustments for age, sex, the corresponding physical activity intensity at baseline, body mass index, pubertal stage and socioeconomic status. Our findings highlight the importance of motor competence development to promote moderate-to-vigorous physical activity during adolescence.

Associations between physical fitness and adherence to the Mediterranean diet with health-related quality of life in adolescents: results from the LabMed Physical Activity Study

Background Physical fitness (PF) and adherence to the Mediterranean diet are important indicators of healthy lifestyles. The purpose of this study is to analyze the independent and combined associations between PF and adherence to Mediterranean diet with health-related quality of life (HRQoL) in adolescents. Methods This is a cross-sectional analysis with 956 Portuguese adolescents aged 12-18 years. HRQoL was measured with the Kidscreen-10 questionnaire. PF was assessed with the ALPHA health-related fitness battery. The 20-m shuttle run test was used for the estimation of cardiorespiratory fitness; handgrip strength and standing long jump tests were applied for the assessment of muscular fitness and the 4 × 10 m shuttle run test for the assessment of motor fitness (speed and agility). The results of the PF tests (cardiorespiratory fitness, muscular fitness and motor fitness) were transformed into standardized values (Z-scores) by age and sex. Adherence to the Mediterranean diet was assessed with the KIDMED index. Regression analysis and analysis of covariance were performed. Results PF (B = 0.228; P < 0.05) and adherence to the Mediterranean diet (B = 0.259; P < 0.05) were positively associated with HRQoL, after controlling for several variables. Participants classified as high PF and high adherence to Mediterranean diet had on average the highest HRQoL score compared with those with low PF and low adherence to Mediterranean diet (F(3, 939) = 4.270; P = 0.005), after adjustments for potential confounders. Conclusions The combination of high PF levels and optimal adherence to Mediterranean diet is positively associated with HRQoL.