Comparison of Adherence to Mediterranean Diet between Spanish and German School-Children and Influence of Gender, Overweight, and Physical Activity.

BACKGROUND: Poor dietary habits and low levels of physical activity (PA) have a strong tendency to track from childhood into adulthood. The Mediterranean Diet (MD) is known to be extremely healthy, associated with lower BMI and a lower risk of obesity in children and adolescents. Therefore, adherence to the MD was compared between Spanish (n = 182) and German (n = 152) children aged 10 to 13 years to examine a possible more "westernized" diet in Spain with a non-Mediterranean country, that traditionally prefers a "Western diet" and to determine the association between adherence to the MD and gender, body composition, and PA levels. METHODS: In the German observational longitudinal cohort study and the Spanish cohort study, body composition and questionnaires (KIDMED, Diet Quality (IAES)) were obtained, and accelerometers (Actigraph) were applied to detect PA. RESULTS: Girls had higher BMI-standard deviation score (SDS) than boys and Spanish girls were less active than boys. Differences were detected in MD habits, such as favorable fruit-, vegetables-, fish-intakes, and dairy products in Spanish children and unfavorable consumptions of fast food, processed bakery goods, candies, and sweet beverages in German children. Independently of country, girls, children with lower BMI-SDS and children with higher PA level were related with better diet quality. CONCLUSION: Spanish children showed higher adherence to MD and diet quality (IAES) compared to German children, but there was a trend toward a more "westernized" diet. Gender, body composition, and PA influenced nutrition regardless of country.

Changes in and the mediating role of physical activity in relation to active school transport, fitness and adiposity among Spanish youth: the UP&DOWN longitudinal study.

BACKGROUND: Longitudinal changes in child and adolescent active school transport (AST), and the mediating role of different intensities of daily physical activity (PA) levels in relation to AST and physical fitness and adiposity indicators is unclear. This study aimed to: 1) describe longitudinal changes in AST, light PA (LPA), moderate- to vigorous-intensity PA (MVPA), physical fitness and adiposity indicators over three time-points; and 2) investigate the mediating role of LPA and MVPA levels on associations between AST and physical fitness and adiposity indicators over three time-points among children and adolescents. METHODS: This longitudinal study comprised 1646 Spanish children and adolescents (48.8% girls, mean age 12.5 years ±2.5) at baseline, recruited from schools in Cádiz and Madrid. Mode of commuting to school was self-reported at baseline (T0, 2011-12), 1-year (T1) and 2-year follow-up (T2). PA was assessed using accelerometers. Handgrip strength, standing long jump and cardiorespiratory fitness (CRF) assessed physical fitness. Height, weight, body mass index, waist circumference, and triceps and subscapular skinfold thickness were measured. Multilevel linear regression analyses assessed changes in AST, PA levels, physical fitness and adiposity indicators over three time-points (T0-T1-T2). Additionally, longitudinal path analysis (n = 453; mean age [years] 12.6 ± 2.4) was used to test the mediating effects of LPA and MVPA levels on the association between AST and physical fitness and adiposity indicators. RESULTS: Multilevel analyses observed decreases in LPA between T0-T1 (ß = - 11.27; p < 0.001) and T0-T2 (ß = - 16.27; p < 0.001) and decreases in MVPA between T0-T2 (ß = - 4.51; p = 0.011). Moreover, changes over time showed increases in handgrip between T0-T1 (ß = 0.78; p = 0.028) and T0-T2 (ß = 0.81; p = 0.046). Path analyses showed that AST was directly positively associated with MVPA at T1 (all, ß ≈ 0.33; p < 0.001). MVPA at T1 mediated associations between AST and CRF at T2 (ß = 0.20; p = 0.040), but not the other outcomes. LPA did not mediate any associations. CONCLUSIONS: Results from longitudinal path analysis suggest that participation in more AST may help attenuate declines in MVPA that typically occur with age and improve CRF. Therefore, we encourage health authorities to promote AST, as a way to increase MVPA levels and CRF among youth.

Physical activity less than the recommended amount may prevent the onset of major biological risk factors for cardiovascular disease: a cohort study of 198 919 adults.

OBJECTIVES: We examined the dose-response relationship between physical activity (PA) and incidence of cardiovascular disease (CVD) risk factors in adults in Taiwan. METHODS: This study included 1 98 919 participants, aged 18-97 years, free of CVD, cancer and diabetes at baseline (1997-2013), who were followed until 2016. At baseline, participants were classified into five PA levels: inactive' (0 metabolic equivalent of task (MET)-h/week), 'lower insufficiently active' (0.1-3.75 MET-h/week), 'upper insufficiently active' (3.75-7.49 MET-h/week), 'active' (7.5-14.99 MET-h/week) and 'highly active' (≥15 MET-h/week]. CVD risk factors were assessed at baseline and at follow-up by physical examination and laboratory tests. Analyses were performed with Cox regression and adjusted for the main confounders. RESULTS: During a mean follow-up of 6.0±4.5 years (range 0.5-19 years), 20 447 individuals developed obesity, 19 619 hypertension, 21 592 hypercholesterolaemia, 14 164 atherogenic dyslipidaemia, 24 275 metabolic syndrome and 8548 type 2 diabetes. Compared with inactive participants, those in the upper insufficiently active (but not active) category had a lower risk of obesity (HR 0.92; 95% CI 0.88 to 0.95), atherogenic dyslipidaemia (0.96; 0.90 to 0.99), metabolic syndrome (0.95; 0.92 to 0.99) and type 2 diabetes (0.91; 0.86 to 0.97). Only highly active individuals showed a lower incidence of CVD risk factors than their upper insufficiently active counterparts. CONCLUSION: Compared with being inactive, doing half the recommended amount of PA is associated with a lower incidence of several common biological CVD risk factors. Given these benefits, half the recommended amount of PA is an evidence based target for inactive adults.

Lifestyle Clusters in School-Aged Youth and Longitudinal Associations with Fatness: The UP&DOWN Study.

OBJECTIVES: To identify lifestyle clusters in children and adolescents, to analyze associations between lifestyle clusters and body fat percentage (BFP) at baseline and 2 years later, and to examine if BFP at baseline is associated with BFP 2 years later. STUDY DESIGN: This longitudinal study involved 1634 Spanish youth (804 girls) aged 8-18 years (mean, 12.45 ± 2.51 years). Cluster analysis was performed by including objectively measured sedentary time and physical activity and self-reported screen time and diet. The associations between cluster membership and BFP was analyzed through general linear models. All the analyses were separated by 3 age groups: older children, younger adolescents, and older adolescents. RESULTS: Four clusters were identified in the 3 age groups: (1) healthy lifestyle cluster (high moderate-to-vigorous physical activity, low screen and total sedentary time), (2) predominantly sedentary cluster, (3) mainly screen time consumers cluster, and (4) nonhealthy lifestyle cluster (predominantly low moderate-to-vigorous physical activity and unhealthy diet). Participants belonging to the healthy lifestyle cluster showed significantly lower BFP at baseline and 2 years later compared with the other profiles. These differences remained significant when adjusted by BFP at baseline within the younger adolescents. Moreover, BFP at baseline positively predicted BFP 2 years later in all groups. CONCLUSIONS: These findings identify distinct lifestyle patterns. These clusters could be useful to develop interventions to reduce overweight and obesity in children and adolescents.

Criterion-related validity of self-reported stair climbing in older adults.

INTRODUCTION: Stair climbing is an activity of daily living that might contribute to increase levels of physical activity (PA). To date, there is no study examining the validity of climbing stairs assessed by self-report. The aim of this study was, therefore, to examine the validity of estimated stair climbing from one question included in a common questionnaire compared to a pattern-recognition activity monitor in older adults. METHODS: A total of 138 older adults (94 women), aged 65-86 years (70.9 ± 4.7 years), from the IMPACT65 + study participated in this validity study. Estimates of stair climbing were obtained from the European Prospective Investigation into Cancer and Nutrition (EPIC) PA questionnaire. An objective assessment of stair climbing was obtained with the Intelligent Device for Energy Expenditure and Activity (IDEEA) monitor. RESULTS: The correlation between both methods to assess stair climbing was fair (ρ = 0.22, p = 0.008 for PA energy expenditure and ρ = 0.26, p = 0.002 for duration). Mean differences between self-report and the IDEEA were 7.96 ± 10.52 vs. 9.88 ± 3.32 METs-min/day for PA energy expenditure, and 0.99 ± 1.32 vs. 1.79 ± 2.02 min/day for duration (both Wilcoxon test p < 0.001). Results from the Bland-Altman analysis indicate that bias between both instruments were -1.91 ± 10.30 METs-min/day and -0.80 ± 1.99 min/day, and corresponding limits of agreement for the two instruments were from 18.27 to -22.10 METs-min/day and from 3.09 to -4.70 min/day, respectively. CONCLUSION: Our results indicate that self-reported stair climbing has modest validity to accurately rank old age participants, and underestimates both PAEE and its duration, as compared with an objectively measured method.

Inflammatory biomarkers and academic performance in youth. The UP & DOWN Study.

Inflammation influences cognitive development in infants and older adults, however, how inflammation may affect academic development during childhood and adolescence remains to be elucidated. This study aimed to examine the association between inflammatory biomarkers and academic performance in children and adolescents. A total of 494 youth (238 girls) aged 10.6 ± 3.4 years participated in the study. Four inflammatory biomarkers were selected: C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and white blood cell (WBC) count. An inflammatory index was created using the above mentioned biomarkers. Academic performance was assessed through schools records. Results showed that three of the four inflammatory biomarkers (CRP, IL-6 and WBC) and the inflammatory index were negatively associated with all academic indicators (ß values ranging from -0.094 to -0.217, all P<0.05) independent of confounders including body fat percentage. Indeed, youth in the highest tertile of the inflammatory index had significantly lower scores in all academic indicators compared with youth in the middle tertile (scores ranging from -0.578 to -0.344) and in the lowest tertile (scores ranging from -0.678 to -0.381). In conclusion, inflammation may impair academic performance independently of body fat levels in youth. Our results are of importance because the consequences of childhood and adolescence inflammation tend to continue into adulthood. Lifestyle interventions in youth may be promising in reducing levels of inflammation beyond the reduction in body fat in order to achieve cognitive benefits.

STRAIGHT-A STUDENTS DISLIKE PHYSICAL EDUCATION IN ADOLESCENCE: MYTH OR TRUTH? THE AVENA, AFINOS AND UP&DOWN STUDIES.

OBJECTIVE: to examine if those adolescents who dislike physical education classes get better results on academic and cognitive performance than their peers. METHODS: participants included 4 226 adolescents from the AVENA, AFINOS and UP&DOWN studies. Physical education enjoyment was assessed with a 7-point Likert scale. Cognitive performance in the AVENA study was assessed using the Spanish version of the SRA Test of Educational Ability. Academic performance in the AFINOS and UP&DOWN studies was assessed through Mathematics and Language grades and the average of both subjects. RESULTS: in the AVENA study we found differences in verbal ability among girls who dislike physical education and their peers (P = 0.033). In the AFINOS study, boys who dislike physical education had higher scores in Language than their peers (P = 0.024). In the UP&DOWN study girls who disliked physical education had higher scores in Language and in the average of Language and Mathematics than their peers (P < 0.001). CONCLUSION: in the AVENA and AFINOS studies adolescents who disliked physical education had similar results in cognitive and academic performance than their peers, but in the UP&DOWN study girls who disliked physical education showed higher results in academic performance than their peers.

Objetivo: conocer si a aquellos adolescentes que no les gusta la educación física obtienen mejores resultados en rendimiento académico y cognitivo que sus compañeros. Métodos: los participantes incluyen 4.226 adolescentes de los estudios AVENA, AFINOS y UP&DOWN. El gusto por la educación física se valoró con una escala Likert de 7 puntos. El rendimiento cognitivo se valoró en el estudio AVENA usando la versión española del SRA Test of Educational Ability. El rendimiento académico se valoró en los estudios AFINOS y UP&DOWN con las notas de Matemáticas, Lengua y la media de Lengua y Matemáticas. Resultados: en el estudio AVENA encontramos diferencias en la habilidad verbal entre las chicas a las que no les gustaba la educación física y sus compañeros (P = 0,033). En el estudio AFINOS los chicos a los que no les gustaba la educación física tenían mejores notas en Lengua que sus compañeros (P = 0,024). En el estudio UP&DOWN las chicas a las que no les gustaba la educación física obtuvieron mejores resultados en Lengua y en la media de Lengua y Matemáticas (P < 0,001). CONCLUSION: en los estudios AVENA y AFINOS los adolescentes a los que no les gusta la educación física obtuvieron resultados similares a los que sus compañeros, mientras que en el estudio UP&DOWN las chicas a las que no les gustaba la educación física obtuvieron mejores resultados en rendimiento académico que sus compañeros.

Correlates of objectively measured physical activity in adolescents with Down syndrome: the UP & DOWN study.

INTRODUCTION: Correlates of physical activity (PA) have not been explored in adolescents with Down syndrome (DS). Understanding correlates of PA could provide information to develop strategies to increase levels of PA in this target population. OBJECTIVE: The aim of this study was to identify potential correlates of PA in adolescents with DS. METHOD: Information about levels of PA and their potential correlates was collected in 98 adolescents with DS (63 males, aged 11-20 years) using accelerometers and proxy-reported questionnaires. Analysis of covariance and multiple linear regression analyses were conducted to examine correlates of PA. RESULT: Our findings showed that participant's age and socioeconomic status were associated with levels of PA as non-modifiable correlates. Also, parental support, father PA, television-viewing time with siblings and with friends were associated with levels of PA as modifiable correlates. DISCUSSION AND CONCLUSION: Both modifiable and non-modifiable factors are associated with levels of PA in adolescents with DS. Therefore, a better understanding of correlates of PA could contribute to develop strategies on PA promotion in adolescents with DS.

Introducción: los correlatos de actividad física (AF) no han sido estudiados en adolescentes con síndrome de Down (SD). Entendiendo los correlatos de AF se podría aportar información para desarrollar estrategias para incrementar los niveles de AF en esta población diana. Objetivo: el objetivo de este estudio fue identificar correlatos de AF en adolescentes con SD. Métodos: la información de los niveles de AF y sus potenciales correlatos fue recogida en 98 adolescentes con SD (63 hombres, con edades comprendidas entre 11-20 años), usando acelerómetros y cuestionarios proxy-reportados. Se utilizó análisis de covarianza y análisis de regresión lineal múltiple para examinar los correlatos de AF. Resultados: nuestros resultados muestran que la edad y el estatus socioeconómico de los participantes fue asociado con niveles de AF como correlatos no modificables. Además, el apoyo de los padres, la AF del padre y el tiempo dedicado a ver la televisión con hermanos y amigos fueron asociados con niveles de AF como correlatos modificables. Discusión y conclusión: ambos factores modificables y no modificables se asocian con niveles de AF en adolescentes con SD. Por lo tanto, una mejor comprensión de los correlatos de AF podría contribuir a desarrollar estrategias de promoción de la AF en adolescentes con SD.

Obese and unfit students dislike physical education in adolescence: myth or truth? The AVENA and UP&DOWN studies.

INTRODUCTION: In the physical education context a well- known myth suggest that obese and unfit youth dislike physical education. OBJECTIVE: To examine if adolescents who dislike physical education have higher levels of fatness and lower of fitness than their peers. METHODS: Participants included 2606 (49.3% girls) adolescents from AVENA and UP&DOWN studies. physical education enjoyment was assessed with a 7-point Likert scale. Fatness was assessed with BMI, skinfolds and waist circumference. Physical fitness was assessed with cardiorespiratory, motor and muscular fitness tests. RESULTS: Boys who dislike physical education had similar levels of fatness and fitness than their peers (all P>0.05). Adolescent girls who dislike physical education had higher levels in body fat (P=0.035), and lower levels in muscular (P=0.007) and motor (P=0.007) fitness than their peers. CONCLUSION: Since only girls who dislike physical education seem to have, albeit weak, higher levels of fatness and lower of fitness than their peers, it partially confirms the myth in adolescent girls.

Introducción: En el contexto de la EF (educación física), un mito bien conocido podría sugerir que a los jóvenes obesos y con baja condición física no les gusta la EF. Objetivo: Examinar si a los adolescentes a los que no les gusta la EF tienen niveles más altos de obesidad y niveles más bajos de forma física que sus compañeros. Métodos: Se tomó a 2606 participantes (49.3% chicas) adolescentes de los estudios AVENA y UP&DOWN. El disfrute de la EF se evaluó empleando una escala Likert de 7 puntos. La obesidad se evaluó mediante el IMC, pliegues cutáneos y circunferencia de la cintura. La condición física fue evaluada mediante pruebas cardiorespiratorias, motoras y musculares. Resultados: Los chicos a los que no les gusta la EF presentaron niveles similares de obesidad que sus compañeros (total P>0.05). Las chicas adolescentes a las que no les gusta la EF presentaron niveles más altos de grasa corporal (P=0.035), y niveles más bajos en condición física muscular (P=0.007) y motora (P=0.007) que sus compañeros. Conclusión: Dado que solo las chicas a las que no les gusta la EF parecen presentar, sin bien levemente, niveles más altos de obesidad y niveles menores de forma física que sus compañeros, el mito se confirma parcialmente para las chicas adolescentes.

Influence of health behaviours on the incidence of infection and allergy in adolescents: the AFINOS cross-sectional study.

BACKGROUND: Some health behaviours are liable to affect the incidence of allergies and/or common infections in young people; however, the extent and ways in which these might occur are mostly unknown. This study examines the association of health behaviours related to physical activity, sedentariness, diet and sleep with allergy and infection symptoms in adolescents, and also with biological markers that might mediate disease incidence. METHODS: The study comprised a total of 2054 adolescents (50.7% girls) from the Madrid region of Spain. The incidence of infection and allergy symptoms three months prior to the study was obtained from a self-administered questionnaire. Physical and sedentary activities, height and weight, food habits and sleep duration were also self-reported and their influence on infection and allergy incidence was assessed by logistic regression analysis. Blood biomarkers (IgE, eosinophil percentage, leptin, interleukin (IL)-2, IL-4, IL-5 and IL-10) were evaluated in a subsample of 198 subjects. RESULTS: Adequate sleep duration (OR = 0.79, 95%CI: 0.64 to 0.97) and unhealthy weight status (overweight/obesity) (OR = 1.35, 95%CI: 1.04-1.74) were independently associated with decreased and increased allergy incidence, respectively. No significant association was observed with infection incidence. IgE and leptin differed between adolescents with and without allergy symptoms. In regression models IgE was significantly associated with inadequate sleep duration and leptin with weight status. CONCLUSION: Excess weight and inadequate sleep duration are independently associated with the incidence of allergy symptoms in adolescents. Adequate sleep duration and weight during adolescence might be relevant for a decreased risk of suffering allergy symptoms.

Patterns of sedentary behavior and compliance with public health recommendations in Spanish adolescents: the AFINOS study / Patrones de sedentarismo y cumplimiento de las recomendaciones de salud pública en adolescentes españoles: estudio AFINOS

The aims of the present study were: (i) describe patterns of sedentary behavior in Spanish adolescents; and (ii) determine the proportion of adolescents that do not meet the public health recommendations for sedentary behavior. This study comprised 1,724 Spanish adolescents (882 girls), aged 13 to 16 years. Patterns of sedentary behavior (TV viewing, use of computer games, console games and surfing the Internet) were assessed using the HELENA sedentary behavior questionnaire. The total proportion of adolescents watching TV, using computer and console games, and surfing the internet for more than two hours daily was 24%, 9%, 7%, and 17%, respectively, on weekdays, and 50%, 22%, 16%, and 35%, respectively, on weekends. Over 63% of the adolescents from the study did not meet the recommendation for sedentary behavior (< 2 hours daily screen time) on weekdays and 87% did not comply with this recommendation on weekends. Since sedentary behavior plays a key role in adolescent health, public health interventions in Spain that take these factors into consideration are needed.

Los objetivos del estudio son: (i) describir los patrones de comportamiento sedentario en adolescentes españoles y (ii) establecer cuántos de ellos no cumplen las recomendaciones de salud pública sobre comportamiento sedentario. Participaron 1.724 adolescentes españoles (882 chicas) entre 13 y 16 años. Los patrones de comportamiento sedentario (ver la televisión, juegos de ordenador, videojuegos y navegar en Internet) fueron evaluados a través del cuestionario HELENA. La proporción total de adolescentes que ven la TV, usan juegos de ordenador o de consola y navegan en Internet durante > 2h los días de diario fue del 24%, 9%, 7% y 17%, respectivamente. Durante los fines de semana, la proporción fue del 50%, 22%, 16% y 35%. Más del 63% del total de la muestra no cumplen las recomendaciones de tiempo sedentario total < 2 horas durante los días de diario y el 87% no lo hace en días del fin de semana. Dado que las conductas sedentarias podrían ser relevantes en la salud de los adolescentes, las intervenciones de salud pública son necesarias en España.

Combined influence of lifestyle risk factors on body fat in Spanish adolescents--the Avena study.

OBJECTIVE: To examine the combined influence of four lifestyle risk factors related to physical activity, television viewing, sleep duration, and meal frequency on body fat (BF) in adolescents. METHOD: This cross-sectional study comprised 1,310 Spanish adolescents (age 13-18.5 years). Lifestyle variables were self-reported and BF indicators (weight, height, six skinfold thicknesses, waist circumference) measured during the years 2000-2002. Lifestyle risk factors were: physically inactive, ≥ 3 h/day watching television, <8 h/day sleep duration, and <5 meals a day. The number of lifestyle risk factors was calculated for each participant, ranging from 0 to 4. RESULTS: The number of lifestyle risk factors was positively associated with sum of six skinfolds, %BF, waist circumference, and waist-height ratio (all p < 0.001). The odds ratios (95% confidence interval) of overweight (including obesity) for groups with 1, 2, and 3-4 lifestyle risk factors compared with those with 0 were 2.86 (1.77-4.62), 3.61 (2.16-6.04), and 5.81 (3.07-10.99), respectively (p for trend <0.001). All the observations were independent of age, gender, race, socioeconomic status, and fat free mass. CONCLUSION: The combined influence of four lifestyle risk factors is positively associated with BF and an approximately sixfold risk of overweight in adolescents.

Behavioural correlates of active commuting to school in Spanish adolescents: the AFINOS (Physical Activity as a Preventive Measure Against Overweight, Obesity, Infections, Allergies, and Cardiovascular Disease Risk Factors in Adolescents) study.

OBJECTIVE: To examine the associations between lifestyle factors and active commuting to school in Spanish adolescents. DESIGN: Cross-sectional study. Lifestyle factors (overall/extracurricular physical activity, television viewing, reading as a hobby, sleep duration, breakfast/fruit intake, smoking and alcohol intake) as well as mode and duration of commuting to school were self-reported. Active commuters were defined as those adolescents who walked or cycled to school. SETTING: Secondary schools in Madrid, Spain. SUBJECTS: Adolescents (n 2029) aged 13 to 17 years. RESULTS: Similar percentages of adolescent boys (57·6 %) and girls (56·1 %) were classified as active commuters to school (P = 0·491). The analysis showed that only adequate sleep duration (OR = 1·35, 95 % CI 1·11, 1·66; P = 0·003) and breakfast consumption (OR = 0·66, 95 % CI 0·49, 0·87; P = 0·004) were independently associated with active commuting to school. CONCLUSIONS: Only those behaviours that occur immediately before commuting to school (sleep and breakfast) are associated with active commuting in Spanish adolescents.

Validity of the Bouchard activity diary in Spanish adolescents.

OBJECTIVE: Valid and simple instruments to assess physical activity (PA) in specific populations are required for health-related research. The aim of the present study was to assess the validity of the Bouchard activity diary (AD) in Spanish adolescents using an activity monitor to compare total PA and moderate-to-vigorous PA (MVPA) obtained by both instruments. DESIGN: Sixty-one Spanish adolescents, aged 12-16 years, completed the Bouchard AD and wore the ActiGraph activity monitor for three consecutive days. Validity was assessed with the Spearman correlation coefficient (rho), the Bland-Altman method and the kappa coefficient. RESULTS: Thirty-seven adolescents were included in the final analysis. Correlations between the activity monitor and the AD administered over the three days (Thursday-Saturday) were moderate (rho = 0.33-0.35, P < 0.05) or non-significant for total PA and moderate (rho = 0.36, P < 0.05) for MVPA. Correlations between the two methods were progressively lower for each subsequent day of testing, for both total PA and MVPA. The Bland-Altman plot illustrated that the Bouchard AD overestimated MVPA (mean difference -32.05 (sd 74.56) min; 95 % limits of agreement 109.61, -173.31 min). Agreements for classification into MVPA tertiles and accordance with the international recommendations of MVPA were fair and moderate, respectively, for the 3 d means. CONCLUSIONS: The Bouchard AD has reasonable validity to assess total PA and MVPA in Spanish adolescents. The results show lower levels of agreement on the third day but it is not clear if this is due to design features (weekday v. weekend) or to participant compliance with the survey or the activity monitoring protocol.

Physical activity as a preventive measure against overweight, obesity, infections, allergies and cardiovascular disease risk factors in adolescents: AFINOS Study protocol.

BACKGROUND: Prior studies addressing the impacts of regular physical activity or sedentary habits on the immune system have been conducted in adults and laboratory settings. Thus, it is practically unknown how a healthy active lifestyle could affect low-grade inflammation processes, infections or allergies in young persons. The AFINOS Study was designed to determine the relationship between the regular physical activity levels of adolescents and overweight, infection, and allergies along with the presence of metabolic and immunological biomarkers of a deteriorated health status. A further objective of the AFINOS Study is to assess the health status and lifestyle habits of an adolescent population in an effort to identify any protective factors that could be used as preventive measures, since many chronic diseases and their associated co-morbidities often persist from adolescence into adulthood. METHODS/DESIGN: This study was conducted as three separate sub-studies in three different populations as follows: (a) Study 1 was performed on a population sample of adolescents; (b) Study 2 on the adolescents' parents; and (c) Study 3 on a subset of the adolescents from Study 1. Study 1 assessed health and lifestyle indicators through a questionnaire administered to a representative sample of adolescents from the Madrid Region (n = 2400) aged 13 to 16 years. In Study 2, the parents of the teenagers participating in Study 1 were required to fill out a questionnaire. Finally in Study 3, body composition, physical activity, health-related physical fitness, and blood measurements were determined in a subset (n = 200) of the individuals included in Study 1. DISCUSSION: This paper describes the rationale, design, and methodologies used in the AFINOS Study. This multidisciplinary, multicenter study seeks to evaluate several aspects of existing relationships between routine physical activity/sedentary behaviour and several health status markers, specifically those related to the immune system. The results of this cross-sectional study will serve for comparisons with the available data obtained in laboratory settings and in adults. In addition, knowledge regarding the health status and lifestyle habits of Spanish adolescents and their parents will be useful for designing preventive measures.