Bright light therapy versus physical exercise to prevent co-occurring depression in adolescents and young adults with attention-deficit/hyperactivity disorder: a multicentre, three-arm, randomised controlled, pilot phase-IIa trial.

Depression is common in attention-deficit/hyperactivity disorder (ADHD), but preventive behavioural interventions are lacking. This randomised controlled, pilot phase-IIa trial aimed to study a physical exercise intervention (EI) and bright light therapy (BLT)-both implemented and monitored in an individual, naturalistic setting via a mobile health (m-health) system-for feasibility of trial design and interventions, and to estimate their effects on depressive symptoms in young people with ADHD. Two hundred seven participants aged 14-45 years were randomised to 10-week add-on intervention of either BLT (10,000 lx; daily 30-min sessions) (n = 70), EI (aerobic and muscle-strengthening activities 3 days/ week) (n = 69), or treatment-as-usual (TAU) (n = 68), of whom 165 (80%) were retained (BLT: n = 54; EI: n = 52; TAU: n = 59). Intervention adherence (i.e. ≥ 80% completed sessions) was very low for both BLT (n = 13, 22%) and EI (n = 4, 7%). Usability of the m-health system to conduct interventions was limited as indicated by objective and subjective data. Safety was high and comparable between groups. Changes in depressive symptoms (assessed via observer-blind ratings, Inventory of Depressive Symptomatology) between baseline and end of intervention were small (BLT: -0.124 [95% CI: -2.219, 1.971], EI: -2.646 [95% CI: -4.777, -0.515], TAU: -1.428 [95% CI: -3.381, 0.526]) with no group differences [F(2,153) = 1.45, p = 0.2384]. These findings suggest that the m-health approach did not achieve feasibility of EI and BLT in young people with ADHD. Prior to designing efficacy studies, strategies how to achieve high intervention adherence should be specifically investigated in this patient group. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03371810, 13 December 2017.

Assessing cardiorespiratory fitness in clinical and community settings: Lessons and advancements in the 100th year anniversary of VO2max.

Cardiorespiratory fitness (CRF) is a well-established biomarker that has applications to all adults across the health and disease spectrum. Despite overwhelming evidence supporting the prognostic utility of CRF, it remains vastly underutilized. CRF is optimally measured via cardiopulmonary exercise testing which may not be feasible to implement on a large scale. Therefore, it is prudent to develop ways to accurately estimate CRF that can be applied in clinical and community settings. As such, several prediction equations incorporating non-exercise information that is readily available from routine clinical encounters have been developed that provide an adequate reflection of CRF that could be implemented to raise awareness of the importance of CRF. Further, technological advances in smartphone apps and consumer-grade wearables have demonstrated promise to provide reasonable estimates of CRF that are widely available, which could enhance the utilization of CRF in both clinical and community settings.

Acute effect of physical activity on academic outcomes in school-aged youth: A systematic review and multivariate meta-analysis.

BACKGROUND: There has been an increase in the number of studies examining the effect of acute and chronic physical activity on academic outcomes in children and adolescents in the last two decades. We aimed to systematically determine the acute effects of physical activity on academic outcomes in school-aged youth and to examine possible moderators. METHODS: We conducted a systematic search using PubMed, Web of Science, SPORTDiscus, and PsycINFO databases (from inception to 11th January 2023) for studies assessing the acute effects of physical activity on academic performance-related outcomes in school-aged youth. A univariate and multivariate meta-analysis was conducted based on a random-effects model with restricted maximum likelihood used to pool the academic outcomes results (Hedge's g). RESULTS: We included 11 articles (803 children and adolescents [range: 6-16 years]) in the systematic review. Overall, acute physical activity increased academic outcomes (Hedge's g = 0.35, 95% CI: 0.20-0.50). Multivariate meta-analyses revealed that physical activity increased academic performance in mathematics (Hedge's g = 0.29, 95% CI: 0.16-0.42) and language (Hedge's g = 0.28, 95% CI: 0.09-0.47). Only behavior change techniques (Hedge's g = 0.54, 95% CI, 0.18-0.90, p < 0.001) played a significant role in this relationship. CONCLUSIONS: A single bout of physical activity can improve academic outcomes in school-aged youth, which may serve as a complementary tool for the educational field. However, the observed heterogeneity in the results indicates that we should interpret the findings obtained with caution.

Do Physical Fitness and Executive Function Mediate the Relationship between Physical Activity and Academic Achievement? An Examination Using Structural Equation Modelling.

Background: Physical activity health benefits are widely known. However, the association between physical activity, physical fitness, executive function, and academic performance need further investigation. Additionally, one of the literature gaps reveals scarce and mixed findings on what mediators of physical activity may affect academic achievement. Purpose: This investigation aims to provide knowledge about the mediation role of physical fitness and executive function in the association of physical activity with academic achievement in a cohort of Spanish schoolchildren using a structural equation modelling approach. Methods: The data for this cross-sectional study were collected from a convenience sample of children from Spain (Balearic Islands) aged between 9 and 13 years. Physical activity levels were self-reported with the Physical Activity Questionnaire for Children; physical fitness was assessed using the International Fitness Scale; executive function was assessed with the Trail Making Test, and children's achievements were collected from the school records. Structural equation modelling was used to explore the relationship between physical activity, physical fitness, executive function, and academic achievement. Findings: Statistically significant positive direct associations were observed between physical activity and physical fitness (ß = 0.46, 95% CI [0.29, 0.64]), physical fitness and executive function (ß = 0.28, 95% CI [0.04, 0.52]), and executive function and academic achievement (ß = 0.46, 95% CI [0.28, 0.65]), while adjusting for the confounding effects of sex and body mass index. Furthermore, indirect associations were observed between physical activity and executive function mediated by physical fitness (ß = 0.13, bias-corrected 95% CI [0.02, 0.31]) and between physical fitness and academic achievement through executive function (ß = 0.13, bias-corrected 95% CI [0.03, 0.32]). Conclusions: This investigation adds to the literature with evidence supporting the idea that regular PA leads to improvements in physical fitness and may support cognitive skills and academic performance in children.

The dynamical association between physical activity and affect in the daily life of individuals with ADHD.

Exercise interventions in mental disorders have evidenced a mood-enhancing effect. However, the association between physical activity and affect in everyday life has not been investigated in adult individuals with ADHD, despite being important features of this disorder. As physical activity and affect are dynamic processes in nature, assessing those in everyday life with e-diaries and wearables, has become the gold standard. Thus, we used an mHealth approach to prospectively assess physical activity and affect processes in individuals with ADHD and controls aged 14-45 years. Participants wore accelerometers across a four-day period and reported their affect via e-diaries twelve times daily. We used multilevel models to identify the within-subject effects of physical activity on positive and negative affect. We split our sample into three groups: 1. individuals with ADHD who were predominantly inattentive (n = 48), 2. individuals with ADHD having a combined presentation (i.e., being inattentive and hyperactive; n = 95), and 3. controls (n = 42). Our analyses revealed a significant cross-level interaction (F(2, 135.072)=5.733, p = 0.004) of physical activity and group on positive affect. In details, all groups showed a positive association between physical activity and positive affect. Individuals with a combined presentation significantly showed the steepest slope of physical activity on positive affect (slope_inattentive=0.005, p<0.001; slope_combined=0.009, p<0.001; slope_controls=0.004, p = 0.008). Our analyses on negative affect revealed a negative association only in the individuals with a combined presentation (slope=-0.003; p = 0.001). Whether this specifically pronounced association in individuals being more hyperactive might be a mechanism reinforcing hyperactivity needs to be empirically clarified in future studies.

Patterns of Active Commuting to School in Spanish Preschool Children and Its Associations with Socio-Economic Factors: The PREFIT Project.

The aims of this study were to describe patterns of active commuting to school (ACS) of preschool children, and to analyse the relationship between ACS and family socio-economic factors. A total of 2636 families of preschoolers (3-to-5 years old) were asked to complete a questionnaire at home about the mode of commuting to school of their children and marital status, educational level, and profession of both father and mother. Chi-square analyses were applied to compare ACS between school grades and gender of the children. To analyse the association of ACS with socio-economic factors, logistic regression analyses were performed. Almost 50% of participants reported ACS of their offspring, with a higher rate in 3rd preprimary grade (5 years old) than in 1st and 2nd preprimary grades (3- and 4-years old. All, p < 0.05). Those preschool children who had parents with lower educational level and no managerial work had higher odds to ACS than those who had parents with higher educational level and managerial work (all, p ≤ 0.001). Around half of the Spanish preschool children included in this study commuted actively to school and families with lower educational levels or worse employment situation were related to active commuting to school.

Objectively measured physical activity and academic performance in school-aged youth: The UP&DOWN longitudinal study.

To examine the longitudinal relationships between objectively measured total volume and specific intensities of physical activity (PA) with academic performance in a large sample of youth aged 6-18 years. A longitudinal study of 1046 youth (10.04 ± 3.10 years) from Spain was followed over 2 years. PA (volume and intensity) was measured by accelerometry. Academic performance was assessed through grades reported on the transcript at the end of the academic year (Mathematics, Language, an average of these two core subjects, and grade point average [GPA]). Longitudinal relationships between PA and four indicators of academic performance were examined using covariance and regression analyses, adjusted for a variety of confounders. Youth Quartile 2 for PA volume at baseline obtained better scores than those who participated in Quartiles 1 or 4 volumes of PA in GPA 2 years later (p = 0.006). There were generally no longitudinal associations between specific PA intensities and any of the academic performance indicators (all p > 0.170). However, a change in light PA over 2 years was inversely associated with three academic indicators in youth (ßrange , -.103 to - 090; all P < 040). Findings suggest that participants in Quartile 2 volume of PA had a better GPA in comparison with Quartiles 1 and 4 volumes of PA during youth, but there was no association with changes in PA volume over time. PA intensity was generally unrelated to academic performance during youth. However, there was an inverted u-shape relationship between light PA changes and GPA.

The effects of a physical activity intervention based on a fatness and fitness smartphone app for University students.

Since the 2012 Lancet Series on physical activity, progress regarding this topic has been negligible at global level. Thus, improving physical activity levels in specific populations through new methodologies is positioned as a priority. The aim of this study was to determine the effects of a physical activity intervention on body fatness composition, and measured and self-reported physical fitness components based on the use of a smartphone app. The investigation included 100 Spanish university students, cluster-randomized into the smartphone app intervention group or a control group (n = 35 and n = 31 respectively, after applying exclusion criteria). The physical activity intervention comprised a 9-week programme designed to promote a healthy physical activity pattern using a smartphone app. Specifically, an mHealth approach was taken containing five BCTs. The results showed that the intervention group improved their physical fitness (F = 8.1, p = .006) and reported better general scores in self-reported physical fitness (F = 7.4, p = .008) over time, in comparison to the control group. However, the intervention group did not show any changes to their fatness. Further research is needed to disentangle which BCTs are more effective to achieve physical health improvements when using physical activity apps.

Smartphone App (2kmFIT-App) for Measuring Cardiorespiratory Fitness: Validity and Reliability Study.

BACKGROUND: There is strong evidence suggesting that higher levels of cardiorespiratory fitness (CRF) are associated with a healthier metabolic profile, and that CRF can serve as a powerful predictor of morbidity and mortality. In this context, a smartphone app based on the 2-km walk test (UKK test) would provide the possibility to assess CRF remotely in individuals geographically distributed around a country or continent, and even between continents, with minimal equipment and low costs. OBJECTIVE: The overall aim of this study was to evaluate the validity and reliability of 2kmFIT-App developed for Android and iOS mobile operating systems to estimate maximum oxygen consumption (VO2max) as an indicator of CRF. The specific aims of the study were to determine the validity of 2kmFIT-App to track distance and calculate heart rate (HR). METHODS: Twenty participants were included for field-testing validation and reliability analysis. The participants completed the UKK test twice using 2kmFIT-App. Distance and HR were measured with the app as well as with accurate methods, and VO2max was estimated using the UKK test equation. RESULTS: The validity results showed the following mean differences (app minus criterion): distance (-70.40, SD 51.47 meters), time (-0.59, SD 0.45 minutes), HR (-16.75, SD 9.96 beats/minute), and VO2max (3.59, SD 2.01 ml/kg/min). There was moderate validity found for HR (intraclass correlation coefficient [ICC] 0.731, 95% CI -0.211 to 0.942) and good validity found for VO2max (ICC 0.878, 95% CI -0.125 to 0.972). The reliability results showed the following mean differences (retest minus test): app distance (25.99, SD 43.21 meters), app time (-0.15, SD 0.94 seconds), pace (-0.18, SD 0.33 min/km), app HR (-4.5, 13.44 beats/minute), and app VO2max (0.92, SD 3.04 ml/kg/min). There was good reliability for app HR (ICC 0.897, 95% CI 0.742-0.959) and excellent validity for app VO2max (ICC 0.932, 95% CI 0.830-0.973). All of these findings were observed when using the app with an Android operating system, whereas validity was poor when the app was used with iOS. CONCLUSIONS: This study shows that 2kmFIT-App is a new, scientifically valid and reliable tool able to objectively and remotely estimate CRF, HR, and distance with an Android but not iOS mobile operating system. However, certain limitations such as the time required by 2kmFIT-App to calculate HR or the temperature environment should be considered when using the app.

Low cardiorespiratory fitness and obesity for ADHD in childhood and adolescence: A 6-year cohort study.

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent disorder in childhood and identifying risk factors associated with developing ADHD during childhood and adolescence is relevant from a clinical and epidemiological point of view. This work examines (a) whether overweight/obesity and low cardiorespiratory fitness (CRF) are associated with increased ADHD symptoms in childhood (cross-sectional analysis), and (b) whether overweight/obesity and low CRF levels during childhood predict increased ADHD symptoms in adolescence (longitudinal analysis). Data were examined from a longitudinal study of Estonian inhabitants who took part in the European Youth Heart Study (EYHS) in 1998 and 1999 (baseline age 9 years), who were re-evaluated 6 years later as part of the longitudinal Estonian Children Personality Behaviour and Health Study (ECPBHS). CRF was determined via an incremental maximal cycle-ergometer test, overweight/obesity was based on body mass index (BMI), and the 7-point af Klinteberg Hyperactivity Scale was used to assess ADHD symptoms at both time points. In the cross-sectional analysis, children with overweight/obesity were at greater risk of ADHD symptoms compared to underweight/normal weight children, as were those unfit compared to fit children (OR = 1.92 and 95%CI = 1.02-3.55, and OR = 1.84 and 95%CI = 1.13-2.98, respectively). The cross-sectional association between BMI and ADHD symptoms was mediated by CRF (z = 2.116, 42.9%; P = .034). The longitudinal analysis showed being unfit in childhood was associated with a greater risk of increased ADHD symptoms 6 years later in adolescence (OR = 2.26 and 95%CI = 1.14-4.47), even after adjusting for baseline ADHD symptoms and BMI. Our result suggests that being unfit is an additional risk factor for increased ADHD symptoms during childhood and adolescence. The association between BMI and ADHD symptoms was mediated by CRF in the cross-sectional analysis, and no association was seen between overweight/obesity and increased ADHD symptoms.

Activity-rest circadian pattern and academic achievement, executive function, and intelligence in children with obesity.

This study aimed to analyze the associations of activity-rest pattern indicators with academic achievement, executive function, and intelligence and to explore whether these associations are mediated by the total gray matter volume among children with overweight/obesity. Ninety-five children (10 ± 1 year, 37 girls) with overweight/obesity (based on the World Obesity Federation body mass index cutoff points) were included in this cross-sectional study. Hip- and wrist-worn ActiGraph GT3X + accelerometers were used to assess the activity-rest pattern. Interdaily stability (IS), intradaily variability (IV), the mean value of the lowest 5 hours (L5), and the mean value of the maximum 10 hours (M10) of activity and their respective timing (TL5, TM10) were used as indicators of the activity-rest pattern throughout the day. Chronotype and social jetlag were used as indicators of circadian preference. Academic achievement, executive function, and intelligence were assessed with standardized tests. Gray matter volume was acquired by magnetic resonance imaging (MRI). IS was positively associated with executive function (ß = 0.244, P = .014). IV was negatively associated with mathematics and academic applications (ß: -0.211 to -0.238, P's ≤ .026). Later TM10 in the day was related to lower writing, academic skills, and intelligence (ß: -0.229 to -0.271, P's ≤ .025). None of the associations found were mediated by gray matter volume. A non-fragmented and stable activity-rest pattern and earlier physical activity in the day were associated with better academic achievement, executive function, and intelligence in children with overweight/obesity. Further studies are required to corroborate or contrast our findings.

Associations of Heart Rate Measures during Physical Education with Academic Performance and Executive Function in Children: A Cross-Sectional Study.

The current evidence for a relation between children's heart rate measures and their academic performance and executive functioning is infancy. Despite several studies observing dose-response effects of physical activity on academic performance and executive function in children, further research using objective measures of the relative intensity of physical activity (e.g., heart rate) is warranted. The present study aimed to inspect associations between heart rate response and various academic performance indicators and executive function domains. A total of 130 schoolchildren between the ages of 9 and 13 years (M = 10.69, SD 0.96 years old; 56.9% boys) participated in a cross-sectional study. Children's heart rate data were collected through participation in physical education classes using the polar TeamTM hardware and software. One week before heart rate measures, academic performance was obtained from the school records in maths, Spanish language, Catalan language, physical education, and Grade point average. Executive function was measured by two domains, cognitive flexibility with the Trail Making Test and inhibition with the Stroop test. Associations between children's heart rate data and academic performance and executive function were analyzed using regression models. Academic performance was found to be positively related to four heart rate measures (ß range, 0.191 to 0.275; all p < 0.040). Additionally, the hard heart rate intensity level was positively related to two academic indicators (ß range, 0.183 to 0.192; all p < 0.044). Three heart rate measures were associated with two cognitive flexibility subdomains (ß range, -0.248 to 0.195; all p < 0.043), and three heart rate measures were related to one inhibition subdomain (ß range, 0.198 to 0.278; all p < 0.028). The results showed slight associations of heart rate responses during physical education lessons with academic performance but did not clearly indicate associations with executive function. Future experimental studies testing associations between different bouts of intensity levels are needed to disentangle the relationship with brain function during childhood.

[Effects of moderate to vigorous intensity interval exercise program on fitness and fatness in 11-and 12-years-old schoolchildren]. / Efectos de un programa de ejercicio interválico de intensidad moderada-vigorosa sobre la condición física y la composición corporal en escolares de 11 y 12 años.

INTRODUCTION: Introduction: there is growing evidence of concern for values in terms of physical condition and body composition alarming that place school child at risk parameters in physical health. Numerous investigations relate physical activity with improvement in physical condition and body composition. Objective: to analyze the effects of a sub-maximal intensity interval exercise program on physical condition (upper body isometric strength in both hands, lower body explosive strength, velocity-agility and cardiorespiratory fitness) and body composition (body mass index, % of body fat, waist circumference and waist/height index), all of them related to health, in schoolchildren of 11 and 12 years. Methods: an intervention was developed in which an experimental group participated and another control group with 28 schoolchildren each. Happened over 8 weeks, with sessions of total 30 minutes before the start of the academic activity 3 days per week. Different intervallic games were made with motor, cognitive and coordination challenges; with a moderate-vigorous intensity (70 %-80 % of maximum heart rate). The registration in physical condition and body composition was made through the ALPHA Battery. Results: significant improvements in isometric strength with both hands and a reduction in waist circumference and waist/height index. Conclusions: the results show significant improvements in indicators of fitness and fatness, however, it requires a long-term intervention to know if the other improvements achieved in the analyzed indicators are significant over time.

INTRODUCCIÓN: Introducción: se evidencia un aumento cada vez mayor de la preocupación debido a condiciones físicas y composición corporal alarmantes, que sitúan a los escolares en unos parámetros de riesgo en lo relativo a la salud física. Numerosas investigaciones relacionan la actividad física con la mejora en la condición física y la composición corporal. Objetivo: analizar los efectos de un programa de ejercicio interválico de intensidad moderada-vigorosa sobre indicadores de condición física (fuerza isométrica manual en ambas manos, fuerza explosiva del tren inferior, velocidad-agilidad y capacidad aeróbica) y de composición corporal (índice de masa corporal, % de grasa corporal, perímetro de cintura e índice cintura/altura), referentes todos ellos para la salud en escolares de 11 y 12 años. Métodos: se desarrolla una intervención en la que participó un grupo experimental y otro control con 28 escolares cada uno de ellos. Transcurrió a lo largo de 7 semanas, con sesiones de 30 minutos totales antes del inicio de la actividad académica, 3 días por semana. Se realizaron diferentes juegos interválicos, con una intensidad moderada-vigorosa (70-80 % de la frecuencia cardíaca máxima). El registro en condición física y composición corporal se realizó a través de la batería ALPHA. Resultados: mejoras significativas en fuerza isométrica con ambas manos y una reducción significativa del perímetro de cintura e índice cintura/altura. Conclusión: los resultados muestran mejoras significativas en indicadores de condición física y composición corporal; sin embargo, se precisa de una intervención de mayor duración para conocer si las otras mejoras logradas en los indicadores analizados consiguen ser significativas con el transcurso del tiempo.

A Single Question of Parent-Reported Physical Activity Levels Estimates Objectively Measured Physical Fitness and Body Composition in Preschool Children: The PREFIT Project.

Physical inactivity is recognized as a determinant of low physical fitness and body composition in preschool children, which in turn, are important markers of health through the lifespan. Objective methods to assess physical activity, physical fitness and body composition in preschool children are preferable; however, they have some practical limitations in the school context. Therefore, the aim of this study was to test whether a single question regarding physical activity level of preschool children, reported by their parents, could be used as an alternative screening tool of physical fitness and body composition. The information was obtained from 10 different cities throughout Spain, gathering a total of 3179 healthy preschool children (52.8% boys and 47.2% girls) aged 3-5 years. Physical activity levels of preschool children were reported by parents using a single question with five response options (very low, low, average, high, or very high). Physical fitness and body composition were assessed with the PREFIT fitness battery. The results showed that parents' perception of their children's physical activity was positively associated with all objectively measured physical fitness components (ßrange = -0.094 to 0.113; all p < 0.020); and negatively with body composition indicators as measured (ßrange = -0.113 to -0.058; all p < 0.001). The results showed significant differences in all physical fitness and body composition z-scores across the parent-reported physical activity levels (all p < 0.017 and all p < 0.001, respectively), as well as, for the fitness index (p < 0.001). Our study suggests that in school settings with insufficient resources to objectively assess fitness and body composition, parents-reported physical activity level by means of a single question might provide useful information about these important health markers in preschool children.

A Systematic Review of Fitness Apps and Their Potential Clinical and Sports Utility for Objective and Remote Assessment of Cardiorespiratory Fitness.

BACKGROUND: Cardiorespiratory fitness (CRF) assessment provides key information regarding general health status that has high clinical utility. In addition, in the sports setting, CRF testing is needed to establish a baseline level, prescribe an individualized training program and monitor improvement in athletic performance. As such, the assessment of CRF has both clinical and sports utility. Technological advancements have led to increased digitization within healthcare and athletics. Nevertheless, further investigation is needed to enhance the validity and reliability of existing fitness apps for CRF assessment in both contexts. OBJECTIVES: The present review aimed to (1) systematically review the scientific literature, examining the validity and reliability of apps designed for CRF assessment; and (2) systematically review and qualitatively score available fitness apps in the two main app markets. Lastly, this systematic review outlines evidence-based practical recommendations for developing future apps that measure CRF. DATA SOURCES: The following sources were searched for relevant studies: PubMed, Web of Science®, ScopusTM, and SPORTDiscus, and data was also found within app markets (Google Play and the App Store). STUDY ELIGIBILITY CRITERIA: Eligible scientific studies examined the validity and/or reliability of apps for assessing CRF through a field-based fitness test. Criteria for the app markets involved apps that estimated CRF. STUDY APPRAISAL AND SYNTHESIS METHODS: The scientific literature search included four major electronic databases and the timeframe was set between 01 January 2000 and 31 October 2018. A total of 2796 articles were identified using a set of fitness-related terms, of which five articles were finally selected and included in this review. The app market search was undertaken by introducing keywords into the search engine of each app market without specified search categories. A total of 691 apps were identified using a set of fitness-related terms, of which 88 apps were finally included in the quantitative and qualitative synthesis. RESULTS: Five studies focused on the scientific validity of fitness tests with apps, while only two of these focused on reliability. Four studies used a sub-maximal fitness test via apps. Out of the scientific apps reviewed, the SA-6MWTapp showed the best validity against a criterion measure (r = 0.88), whilst the InterWalk app showed the highest test-retest reliability (ICC range 0.85-0.86). LIMITATIONS: Levels of evidence based on scientific validity/reliability of apps and on commercial apps could not be robustly determined due to the limited number of studies identified in the literature and the low-to-moderate quality of commercial apps. CONCLUSIONS: The results from this scientific review showed that few apps have been empirically tested, and among those that have, not all were valid or reliable. In addition, commercial apps were of low-to-moderate quality, suggesting that their potential for assessing CRF has yet to be realized. Lastly, this manuscript has identified evidence-based practical recommendations that apps might potentially offer to objectively and remotely assess CRF as a complementary tool to traditional methods in the clinical and sports settings.

Sports participation and low back pain in schoolchildren.

BACKGROUND: Low back pain (LBP) is one of the biggest health problems worldwide. OBJECTIVES: The purpose of this study was to investigate the association between sports participation (duration and type) and LBP related outcomes in childhood. METHODS: This cross-sectional study involved 5th and 6th grade primary school students. The final sample included 2,032 children aged 10-12 years old. Children completed a questionnaire about the prevalence of LBP and some LBP-related outcomes. In addition, the participants were surveyed about the type of sport they did and the duration. RESULTS: There appears to be no relation between sports participation and severity of LBP-related outcomes studied, independently of their duration. Participating in football ⩾ 4 hours per week was associated with a decrease of six LBP-related outcomes (OR ranging from 0.54 to 0.66). Basketball participation does not seem to affect the development of back problems amongst children. CONCLUSIONS: It can be suggested with caution that doing sport is not dangerous for LBP problems in children aged 10-12 years old. Nevertheless, this suggestion should be tested with further longitudinal and intervention studies to confirm the results.

A Mediation Analysis on the Relationship of Physical Fitness Components, Obesity, and Academic Performance in Children.

OBJECTIVES: To examine the relationship between a battery of obesity indicators and physical fitness components with academic performance in children and to explore the combined and mediation role of the physical fitness components in the relationship between obesity and academic performance in children. STUDY DESIGN: A cross-sectional study including data from 250 Spanish schoolchildren (Balearic Islands) between 10 and 12 years of age (mean age, 10.98 ± 0.76 years) was conducted. Obesity measures (body mass index, body fat, waist circumference, hip circumference, and waist-to-height ratio), physical fitness components (cardiorespiratory fitness, muscular fitness, and speed-agility), and academic performance (Spanish language, Catalan language, English language, natural sciences, social sciences, arts, physical education, religion, and grade point average [GPA]) were collected. RESULTS: All obesity measures were negatively related to at least 3 of the 10 academic indicators, including GPA (ß range, -0.135 to -0.229; all P < .05). Cardiorespiratory fitness and speed-agility were positively related to all academic indicators (ß range, 0.182 to 0.350; all P < .046) and muscular fitness with 3 academic indicators (ß range, 0.143 to 0.253; all P < .039). Children considered as fit had better academic performance than their unfit peers (score +0.75; P = .001). The association between body mass index and GPA was mediated by cardiorespiratory fitness and speed-agility. CONCLUSIONS: This investigation contributes to the current knowledge by adding evidence about the crucial role of physical fitness in terms of academic performance rather than obesity status, suggesting that physical fitness may ameliorate the negative influence of obesity on academic performance.

Bright light therapy versus physical exercise to prevent co-morbid depression and obesity in adolescents and young adults with attention-deficit / hyperactivity disorder: study protocol for a randomized controlled trial.

BACKGROUND: The risk for major depression and obesity is increased in adolescents and adults with attention-deficit / hyperactivity disorder (ADHD) and adolescent ADHD predicts adult depression and obesity. Non-pharmacological interventions to treat and prevent these co-morbidities are urgently needed. Bright light therapy (BLT) improves day-night rhythm and is an emerging therapy for major depression. Exercise intervention (EI) reduces obesity and improves depressive symptoms. To date, no randomized controlled trial (RCT) has been performed to establish feasibility and efficacy of these interventions targeting the prevention of co-morbid depression and obesity in ADHD. We hypothesize that the two manualized interventions in combination with mobile health-based monitoring and reinforcement will result in less depressive symptoms and obesity compared to treatment as usual in adolescents and young adults with ADHD. METHODS: This trial is a prospective, pilot phase-IIa, parallel-group RCT with three arms (two add-on treatment groups [BLT, EI] and one treatment as usual [TAU] control group). The primary outcome variable is change in the Inventory of Depressive Symptomatology total score (observer-blinded assessment) between baseline and ten weeks of intervention. This variable is analyzed with a mixed model for repeated measures approach investigating the treatment effect with respect to all three groups. A total of 330 participants with ADHD, aged 14 - < 30 years, will be screened at the four study centers. To establish effect sizes, the sample size was planned at the liberal significance level of α = 0.10 (two-sided) and the power of 1-ß = 80% in order to find medium effects. Secondary outcomes measures including change in obesity, ADHD symptoms, general psychopathology, health-related quality of life, neurocognitive function, chronotype, and physical fitness are explored after the end of the intervention and at the 12-week follow-up. DISCUSSION: This is the first pilot RCT on the use of BLT and EI in combination with mobile health-based monitoring and reinforcement targeting the prevention of co-morbid depression and obesity in adolescents and young adults with ADHD. If at least medium effects can be established with regard to the prevention of depressive symptoms and obesity, a larger scale confirmatory phase-III trial may be warranted. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00011666. Registered on 9 February 2017. ClinicalTrials.gov, NCT03371810. Registered on 13 December 2017.

Effects of a Whatsapp-delivered physical activity intervention to enhance health-related physical fitness components and cardiovascular disease risk factors in older adults.

BACKGROUND: This pilot study evaluated the feasibility and preliminary effectiveness of a 10-week WhatsApp-based intervention aimed at enhancing health-related physical fitness components and cardiovascular disease (CVD) risk factors compared with a face-to-face condition. METHODS: Participants (N.=32) were assigned to one of three groups: training group (N.=16), mobile group (N.=7) and control group (N.=9). Training group and mobile group performed the same training program, based on strength training with elastics bands and aerobic exercise, during 10 weeks; only the delivery mode differed. RESULTS: The mobile group increased handgrip strength, aerobic capacity and decreased systolic blood pressure and heart rate after exercise though there were no significant differences respect to control group. The training group decreased significantly systolic blood pressure (P=0.038), diastolic blood pressure (P=0.005), mean arterial pressure (P=0.006) and heart rate after exercise (P=0.002), respect to control group. CONCLUSIONS: Comparison between training and mobile group showed that WhatsApp-based physical activity intervention was less effective than face-to-face condition. The results indicate that the use of an online social network produced slight changes in some health-related physical fitness components and CVD risk factors.