Reliability and validity of two frequently used self-administered physical activity questionnaires in adolescents

Anxiety, Sleep Problems, and Vigorous Physical Activity: Bidirectional Associations from Early Adolescence to Early Adulthood in Swedish Adolescents

Anxiety symptoms and sleep problems typically emerge during adolescence and are frequently intertwined. However, there is a dearth of knowledge concerning their reciprocal influence and whether physical activity might play a protective role in this relationship. The present study aims at filling this gap exploring also the moderating role of sex. 915 13-year-old Swedish adolescents (56% girls) answered a survey conducted four times: at ages 13 (T1), 16 (T2), 19 (T3), and 22 (T4). A random intercept cross-lagged panel model was used. At within-levels, sleep problems and anxiety symptoms had a bidirectional positive association in middle adolescence. Vigorous physical activity and anxiety symptoms showed a reciprocal negative association from middle adolescence. Vigorous physical activity and sleep problems were reciprocally associated only in late adolescence. Associations were the same for girls and boys. This study demonstrated that the relations between anxiety symptoms, sleep problems, and vigorous physical activity cannot be understood without adopting a developmental perspective and that middle adolescence is a crucial period to plan interventions to reduce anxiety symptoms and sleep problems.

Family structure and the association with physical activity-Findings from 40 countries participating in the Health Behaviour in School-aged Children (HBSC) study

BACKGROUND

The family has been acknowledged as central to developing physical activity (PA) beliefs and behaviours. However, increased diversity in family structures has developed over the last decades. This study examines the association between family structure and PA among adolescents and cross-national variations in the associations.

METHODS

The data are from the 2013/14 Health Behaviours in School-Aged Children study, involving nationally representative samples of 11-, 13- and 15-year-olds (n = 211,798) from 40 countries. Multilevel Poisson regression analysis was used to examine the associations between family structure and moderate to vigorous physical activity (MVPA) and vigorous physical activity (VPA) by age, gender, socioeconomic status (SES), and geographic region.

RESULTS

Living with one versus two parents was associated with a reduced likelihood of daily 60 min MVPA for boys (IRR = 0.96, 95% CI: 0.92, 0.99) and ≥ 4 times/week VPA (IRR 0.93, 95% CI: 0.91, 0.95). This impact on MVPA differed across individual-level SES (high SES; IRR = 0.92, (p <0.05), low SES; IRR = 1.04, (ns)), and was for VPA only significant for those with siblings (IRR = 0.93, 95% CI: 0.91, 0.96). Cross-country variations in the association between living with one versus two parents were observed, most pronounced for VPA. These differences varied by region, primarily explained by country-level SES differences between regions. The likelihood of daily 60 min MVPA also increased with siblings in the main house (IRR 1.11, 95% CI: 1.07, 1.14), and ≥ 4 times/week VPA decreased with grandparents in the main house (IRR 0.91, 95% CI: 0.89,0.94).

CONCLUSIONS

Family structure correlated with PA, but cross-country differences exist. The findings are relevant for the development of policies and programs to facilitate PA, especially in countries where living with one versus two parents was unfavourable. Additional country-specific research is needed to identify challenges for engaging in PA related to family structure.

Secular trends in risk factors for adolescent anxiety and depression symptoms: the Young-HUNT studies 1995-2019, Norway

In recent decades, increases in mental health problems in adolescents have been reported from several large population-based surveys. This raises questions about changes in underlying risk and protective factors that can inform future intervention strategies. Population data were collected from 1995 to 2019 in three waves of the Young-HUNT studies in Norway to map decennial trends in the prevalence of established risk factors for, and their associations with, adolescent mental health problems. All adolescents (aged 13-19 years) attending lower and upper secondary school in the county of Trøndelag were invited, representing three historical cohorts of 25,245 unique adolescents. Mental health problems (HSCL-5) and established mental health risk factors were self-reported. Using a generalized linear model and linear regression, we calculated changes in relative and absolute differences between risk factors and mental health problems. Overall, the prevalence of established risk factors for mental health problems in adolescence increased markedly between 1995 and 2019, especially in girls. Prominent increases were observed for fatigue, bullying, musculoskeletal pain and migraine, loneliness, and overweight. Furthermore, with the exception of excess alcohol use and family economy, associations between each risk factor and adolescent mental health problems strengthened over the same time span in girls, but less among boys. Our findings suggest that several modifiable risk factors for poor mental health in adolescence are increasing, especially among girls, and should be targeted in community, school, and in clinical settings.

Toward an Understanding of GSD5 (McArdle disease): How Do Individuals Learn to Live with the Metabolic Defect in Daily Life

BACKGROUND

Glycogen storage disease type 5 (GSD) is an autosomal recessive inherited metabolic myopathy caused by a deficiency of the enzyme muscle glycogen phosphorylase. Individuals with GSD5 experience physical activity intolerance.

OBJECTIVE

This patient-led study aimed to capture the daily life experiences of GSD5, with a focus on adapting to and coping with their physical activity intolerance.

METHODS

An online survey was composed in close collaboration with patient organizations. It consisted of customized and validated questionnaires on demographics, general health and comorbidities, physical activity, psychosocial well-being and functioning, pain, fatigue and adapting to and coping with GSD5.

RESULTS

One hundred sixty-two participants (16 countries) participated. The majority, n = 86 (69%) were from the Netherlands, USA or UK. We observed a high rate of misdiagnosis prior to GSD5 diagnosis (49%), surprisingly a relatively high proportion had not been diagnosed by DNA testing which is the gold standard. Being diagnosed had a strong impact on emotional status, daily life activities and important life choices. A large proportion had not received any rehabilitation (41%) nor medical treatment (57%) before diagnosis. Engagement in vigorous and moderate physical activity was reduced. Health related quality of life was low, most likely related to low physical health. The median Fatigue Severity Score was 4.3, indicating moderate to severe fatigue. Participants themselves had found various ways to adapt to and cope with their disability. The adaptations concerned all aspect of their life, including household chores, social and physical activities, and work. In addition to lack of support, participants reported limited availability of information sources.

CONCLUSION

Participants have provided guidance for newly diagnosed people, including the advice to accept one's limited abilities and maintain an active lifestyle. We conclude that adequate counseling on ways of adapting and coping is expected to increase both health-related quality of life and physical activity.

Probably the most active population in the world: accelerometer measurements of 72 school-children in Greenland

Physical activity is the most important lifestyle factor to contribute to a healthy early life. International recommendations are that children should be vigorously physically active for at least 1 h per day, and in Greenland, authorities have claimed a goal of being the world's most active population. Since 1994, the Health Behaviour in School-aged Children (HBSC) has measured physical activity among school-children in Greenland by questionnaire data, but the measurement properties of self-reported data in comparison to more objectively measured accelerometer data are unknown. The present paper describes the first study using clinical measures of physical activity among Greenlandic youth. Seventy-two school-children (56% girls) with a mean age of 12 years (range 25%; 75% was 11.5; 12.25) wore accelerometers for seven consecutive days, and data produced significant and informative findings for both practice and future research. Fifty-two per cent of the school-children met the international recommendations of being physically active >1 h per day, when measured by accelerometers, but self-reported data reported a prevalence of 10% meeting the recommendations. A majority of this sample of Greenlandic school-children lives up to international recommendations, which indicates that the goal of being the world's most active population is within reach.

Physical health and neurodevelopmental outcome in 7-year-old children whose mothers were at risk of gestational diabetes mellitus: a follow-up of a randomized controlled trial

INTRODUCTION

Children born to mothers with gestational diabetes mellitus (GDM) are at risk of metabolic disturbances such as diabetes mellitus and overweight. However, few have examined the outcome of children whose mothers were at risk of GDM. The aim of the study was to investigate how mothers' risk of developing GDM affects physical health and neurodevelopment of the children at 7 years of age.

MATERIAL AND METHODS

This is a secondary analysis of a follow-up study of a multicenter randomized controlled trial including 855 pregnant women, carried out at St. Olavs Hospital, Trondheim University Hospital, and Stavanger University Hospital in Norway from 2007 to 2009. Risk factors for developing GDM included age >40 years, diabetes in near family, previous child with birthweight ≥4500 g and pre-pregnancy body mass index (BMI) ≥25 kg/m2 . Data on GDM risk factors were available for 750 women, who were divided into a risk group if they had one or more risk factors for developing GDM (n = 238) and a no risk (n = 512) group. At 7 years of age, 72 children born to mothers in the risk group and 194 children born to mothers in the no risk group participated. The children's height, weight and physical activity were reported by their parents. Neurodevelopmental outcomes were assessed by using the Five-to-Fifteen questionnaire, which includes motor skills, executive functions, perception, memory, language, social skills, and emotional/behavioral problems.

RESULTS

Most women had only one risk factor for GDM, and pre-pregnancy overweight was the most prevalent risk factor. Children of mothers in the risk group had higher birthweight and length. At the 7-year follow-up, they had a higher weight and BMI, and the odds ratio of being overweight was 3.0 (95% confidence interval 1.1-8.3). There was no group difference in the children's physical activity and their neurodevelopmental outcomes were similar.

CONCLUSIONS

We found higher BMI and increased risk of overweight in children born to mothers with one or more risk factors for developing GDM. A focus on preventing pre-pregnancy overweight should be encouraged.

Data from the European registry for patients with McArdle disease (EUROMAC): functional status and social participation

BACKGROUND

The European registry for individuals with GSD5 and other muscle glycogenosis (EUROMAC) was launched to register rare muscle glycogenosis in Europe, to facilitate recruitment for research trials and to learn about the phenotypes and disseminate knowledge about the diseases. A network of twenty collaborating partners from eight European countries and the US contributed data on rare muscle glycogenosis in the EUROMAC registry.

METHODS

Following the initial report on demographics, neuromuscular features and comorbidity (2020), we here present the data on social participation, previous and current treatments (medication, supplements, diet and rehabilitation) and limitations. Furthermore, the following questionnaires were used: Fatigue severity scale (FSS), WHO Disability Assessment Scale (DAS 2.0), health related quality of life (SF36) and International Physical Activity Questionnaire (IPAQ).

RESULTS

Of 282 participants with confirmed diagnoses of muscle glycogenosis, 269 had GSD5. Of them 196 (73%) completed all questionnaires; for the others, the data were incomplete. The majority, 180 (67%) were currently working. Previous medical treatments included pain medication (23%) and rehabilitation treatment (60%). The carbohydrate-rich diet was reported to be beneficial for 68%, the low sucrose diet for 76% and the ketogenic diet for 88%. Almost all participants (93%) reported difficulties climbing stairs. The median FSS score was 5.22, indicating severe fatigue. The data from the WHODAS and IPAQ was not of sufficient quality to be interpreted.

CONCLUSIONS

The EUROMAC registry have provided insight into the functional and social status of participants with GSD5: most participants are socially active despite limitations in physical and daily life activities. Regular physical activity and different dietary approaches may alleviate fatigue and pain.

Assessment of physical activity among adolescents: a guide to the literature

Purpose

The aim of this article is to systematically review articles and annual reports concerning young peoples' physical activity (PA) and linking this to considerations of the state and national defense.

Method

A systematic search of the literature included an analysis of publications accessible in global databases and other available books, student papers, and projects. The articles and reports were categorized based on year of publication, methods used, age of respondents, sample size, country, and digital object identifier (DOI).

Results

The result of this search is an overview of the extent and manner in which the worldwide scientific community is addressing the current situation and the long-term development of the physical fitness of adolescents. This publication also maps to what extent professional publications and articles are addressing PA from the perspective of the needs of armies and armed forces of various countries around the world.

Conclusions

The article provides a systematic overview of methods used to measure PA, and an overview of articles dealing with assessing PA. The examined articles indicate that from the perspective of not only national defense, but also health and overall quality of life, in particular, we need initiatives to encourage and motivate young people to increase their everyday PA. The research therefore also includes an overview of factors that may considerably influence PA. The results ascertained in this publication will be used, i.a. for investigating a longitudinal defense research project of the Ministry of Defense of the Czech Republic in which the authors are participating.

Adolescent determinants of life-course leisure-time vigorous physical activity trajectories: a 27-Year longitudinal study

BACKGROUND

Adolescence is regarded as formative years for building the foundations for life-long health and well-being, and adolescent determinants of physical activity (PA) development is particularly interesting. Novel approaches for the study of PA development, such as group-based trajectory modelling, opens for the possibility of identifying different patterns in the relationship among several known determinants of PA. This study aimed to explore how demographic, psychological and social factors in early adolescence determine membership in four distinct leisure-time vigorous physical activity (LVPA) trajectories from 13 to 40 years.

METHODS

This study is based on data from the Norwegian Longitudinal Health Behaviour Study, following a cohort born in 1977 from Western Norway. Four trajectories identified using latent class growth analysis, based on self-reposted LVPA (n = 1103, 45.5% women) measured ten times from age 13 to age 40 and 17 different adolescent determinants, were used in a multivariate multinomial logistic regression.

RESULTS

We found that gender (male), VPA intentions the next year and athletic identity associated with belonging to the two trajectories reporting the highest levels of LVPA in adolescence, while VPA intentions in ten years were associated with belonging to the active trajectory compared to the decreasingly active and low active trajectories Enjoyment increased the odds of belonging to the increasingly and decreasingly active trajectories compared to the low active trajectory. In addition, two of the social determinants, mother's PA and emotional support from father, were associated with belonging to the increasingly active trajectory when compared to the low active trajectory. Higher family income increased the odds of belonging to the increasingly active compared to the decreasingly active trajectory.

CONCLUSIONS

Both demographic, psychological, and social factors were identified as determinants of LVPA trajectory membership, and the findings support previous research related to the importance of intentions, but also indicate that enjoyment, role modelling and emotional support in PA can be of great importance to LVPA promotion among adolescents.

Adolescents' Out-of-School Physical Activity Levels and Well-Being during the COVID-19 Restrictions in Greece: A Longitudinal Study

The present study aimed to identify the impact of social distancing measures on adolescents' physical activity (PA) levels and well-being during the implementation of COVID-19 restrictive measures. There were 438 participants (207 boys and 231 girls), aged 12 to 15 years old (M = 13.5, SD = 0.55). They completed online questionnaires on well-being and PA in three waves (December 2020, February 2021, and June 2021). Correlation analyses were conducted to examine the relationship between well-being and PA variables in the three measurements. Additionally, separate three-way repeated-measures ANOVAs were conducted to capture possible differences in students' moderate to vigorous physical activity (MVPA) levels, life satisfaction, and subjective vitality among the three measurements due to gender, age, and interaction between gender and age. A significant relation emerged between the MVPA variables and well-being. In all measurements, adolescents' PA levels did not meet the World Health Organization (WHO) recommendations of at least 60 min per day in MVPA. Students' MVPA levels, life satisfaction, and subjective vitality were significantly higher in the third measurement compared to the first and second ones. Moreover, significant differences emerged in life satisfaction and subjective vitality between boys and girls in the first and third measurements, respectively. The COVID-19 restrictions appeared to negatively influence adolescents' PA and well-being. Policymakers aimed at facilitating adolescents' well-being in a similar situation in the future should not adopt measures restricting the participation of adolescents in PA.

Leisure-time physical activity trajectories from adolescence to adulthood in relation to several activity domains: a 27-year longitudinal study

BACKGROUND

Insufficient physical activity (PA) levels among adolescents and adults make promoting PA a public health priority. Although most people exhibit low or decreasing levels of PA, other groups increase or maintain high levels of activity. These different groups may engage differently in activity domains during their leisure time. This study aimed to identify distinct trajectories of leisure-time vigorous physical activity (LVPA) and to explore whether these trajectories are characterised by differences in four activity domains (participation in organised sports clubs, diversity in leisure-time activities, outdoor recreation, and peer PA) over the life course.

METHODS

Data were drawn from the Norwegian Longitudinal Health Behaviour Study. The sample of participants (n = 1103, 45.5% female) was surveyed 10 times from age 13 years in 1990 to age 40 years in 2017. LVPA trajectories were identified using latent class growth analysis, and mean differences in activity domains were studied using the one-step BCH approach.

RESULTS

Four trajectories were identified: active (9%), increasingly active (12%), decreasingly active (25%), and low active (54%). Overall, this analysis showed a declining tendency in LVPA from age 13 to 40 years except for the increasingly active trajectory. Belonging to a trajectory with a higher LVPA level was related to higher mean levels of the included activity domains. Compared with those in the increasing trajectory, people belonging to the decreasing trajectory reported higher mean participation levels in and age at becoming a member of sports clubs, diversity in leisure-time activities, and best friend's activity level during adolescence. However, in young adulthood, people in the increasingly active trajectory reported significantly higher mean levels for the same variables.

CONCLUSIONS

The development of LVPA from adolescence to adulthood is heterogeneous, suggesting the need for targeted health promotion initiatives. The largest trajectory group included more than 50 percent and was characterized by low levels of LVPA, less engagement in PA domains and fewer active friends. There seems to be little carry-over effect of engagement in organised sports in adolescence regarding level of LVPA later in life. Changes in social surroundings throughout the life span, such as having friends who are more or less engaged in PA, may assist or hinder health enhancing engagement in LVPA.

Questionnaires Measuring 24-Hour Movement Behaviors in Childhood and Adolescence: Content Description and Measurement Properties-A Systematic Review

BACKGROUND

We aim to systematically review the literature on measurement properties of self- and proxy-reported questionnaires measuring 24-hour movement behaviors in children and adolescents.

METHODS

PubMed, PsycINFO, SPORTDiscus, and EMBASE were searched until June 2021. Studies were included if the sample size for validity studies had 50 participants (minimum) and included, at least, both validity and test-retest reliability results of questionnaires. The review followed an adaptation of the Consensus-based Standards for the selection of health Measurement INstruments guidelines, to evaluate the quality of measurements properties of the questionnaires (content, convergent and criterion validity, reliability, measurement error, and responsiveness), as well as the risk of bias of each measurement property.

RESULTS

This review included 29 studies, describing 37 questionnaires. Sixty-eight percent showed "adequate" content validity. None of the questionnaires showed overall "adequate" criterion validity, and the risk of bias was "very low" for 92%. One questionnaire showed "adequate" convergent validity, and 73% of the studies were classified with a "high risk of bias." Seven questionnaires showed "adequate" reliability, and 27.3% of the studies were rated with a "very low risk of bias." None of the questionnaires showed "adequate" criterion validity and reliability, simultaneously.

CONCLUSIONS

Existing questionnaires have insufficient measurement properties, and none considered the 24-hour movement behavior paradigm. These results highlight the need for better questionnaires of movement behavior combinations, to improve the monitoring and surveillance systems of 24-hour movement behaviors in this population.

Development of the Children and Adolescents Physical Activity and Sedentary Questionnaire (CAPAS-Q): Psychometric Validity and Clinical Interpretation

BACKGROUND

Pediatricians' clinical practice and health interventions in youths require instruments with adequate psychometric properties to assess physical activity (PA), sedentary behaviors (SB), and their subdomains.

OBJECTIVE

To assess the psychometric properties of the Children and Adolescents Physical Activity and Sedentary-Questionnaire (CAPAS-Q) in healthy French children and adolescents.

METHODS

The CAPAS-Q has been developed through a rigorous collective procedure and consists of a 31 items self-administered questionnaire evaluating children's 7-day PA and SB dimensions and subdomains. Participants (n = 103, aged 8-18 years old) completed the questionnaire twice (7 days apart) and wore an ActiGraph GT3X&nbsp;+ accelerometer for 7 days. Anthropometric measurements and body composition were assessed.

RESULTS

Cronbach alpha for PA and SB dimensions were 0.71 and 0.68, respectively. Reproducibility was found moderate to good, with Lin's coefficients of 0.69 and 0.68 for PA and SB dimensions, respectively. Reproducibility was higher for adolescents compared to children. PA dimension was positively correlated with moderate PA, vigorous PA, moderate to vigorous PA, and total PA times and negatively correlated with SB time (p < 0.05). SB dimension and screen time were positively correlated with SB time and negatively correlated with LPA, MPA, MVPA, and total PA times (p < 0.05). Spearman correlation coefficients were fair to moderate, ranging between 0.23-0.45.

CONCLUSION

The CAPAS-Q proposes a reliable and valid evaluation of French children and adolescents' PA and SB, providing clinicians with potential intervention levels to improve youth movement behaviors.

Comparison of core stabilization techniques on ultrasound imaging of the diaphragm, and core muscle thickness and external abdominal oblique muscle electromyography activity

BACKGROUND

To restore core stability, abdominal drawing-in maneuver (ADIM), abdominal bracing (AB), and dynamic neuromuscular stabilization (DNS) have been employed but outcome measures varied and one intervention was not superior over another.

OBJECTIVE

The purpose of this study was to compare the differential effects of ADIM, AB, and DNS on diaphragm movement, abdominal muscle thickness difference, and external abdominal oblique (EO) electromyography (EMG) amplitude.

METHODS

Forty-one participants with core instability participated in this study. The subjects performed ADIM, AB, and DNS in random order. A Simi Aktisys and Pressure Biofeedback Unit (PBU) were utilized to measure core stability, an ultrasound was utilized to measure diaphragm movement and measure abdominal muscles thickness and EMG was utilized to measure EO amplitude. Analysis of variance (ANOVA) was conducted at P< 0.05.

RESULTS

Diaphragm descending movement and transverse abdominis (TrA) and internal abdominal oblique (IO) thickness differences were significantly increased in DNS compared to ADIM and AB (P< 0.05). EO amplitude was significantly increased in AB compared to ADIM, and DNS.

CONCLUSIONS

DNS was the best technique to provide balanced co-activation of the diaphragm and TrA with relatively less contraction of EO and subsequently producing motor control for efficient core stabilization.

Reliability and validity of using the global school-based student health survey to assess 24 hour movement behaviours in adolescents from Saudi Arabia

This study aimed to examine the reliability and validity of Global School-based Student Health Survey (GSHS) to measure 24-hour movement behaviours (moderate-to-vigorous physical activity - MVPA; sedentary behaviour in the form of recreational screen time - ST; and sleep) in Saudi Arabian youths. A total of 120 (50% female) participants aged 12-15 years old were recruited from eight Saudi public middle schools. Participants completed GSHS survey twice and wore GENEActiv accelerometers for seven consecutive days and completed a diary log. ICC indicated moderate reliability in all 24-hour movement behaviours (ICC = 0.41 - 0.60), whereas ST and sleep were strongly reliable for females only (ICC = 0.61 - 0.80). Kappa agreements for all 24-hr movement behaviours were moderate (k = 0.41 - 0.60), but fair in MVPA and ST for males only (k = 0.21 - 0.40). Spearman's indicated low validity (r = 0.1 - 0.3) in MVPA and sleep between GSHS and GENEActiv. However, kappa test results indicated poor-to-slight agreements (k = <0.00 - 0.2) in MVPA and sleep, but fair in MVPA for males only (k = 0.21 - 0.4). GSHS provided good reliability for single items of 24-hour movement behaviours, and the validity was acceptable and in line with other comparable questionnaires.

Test-retest reliability of selected HBSC items in Vietnam: well-being, physical and sedentary activities, and eating behaviours

Background

Valid and reliable research tools to assess children’s and adolescent’s health-related behaviour are highly needed across the globe. Rapid economic development, globalization, and associated lifestyle challenges observed in most countries support the need for high-quality evidence in adolescents to target health-promoting policies and interventions. This study aims to examine the test–retest reliability of selected well-being, physical and screen-time related siting activities, and eating behaviour items of the Health Behaviour in School-Aged Children (HBSC) questionnaire in a sample of Vietnamese adolescents.

Methods

Data were collected in autumn 2018 in Vietnam (3-week interval). The sample consisted of 410 adolescents (41.0% of boys; mean age = 12.61; SD = 1.24).Test–retest reliability was evaluated using the single measure Intraclass Correlation Coefficients (ICC) and Cohen’s kappa statistic stratified by sex, grade and place of residence (urban or rural).

Results

The reliability analyses of the well-being items were poor to good ICC values (0.43–0.79) and moderate to large Cohen’s kappa values (0.33–0.77). The physical activity and eating behaviour items were moderate (ICC = 0.54–0.65; Cohen’s kappa = 0.38–0.57). The screen-time related siting activities items were moderate to large (ICC = 0.51–0.72; Cohen’s kappa = 0.42–0.53). There was more item stability among females than males. The social media item was not as stable for 6^th graders (ICC = 0.45) compared with older adolescents (ICC 0.68–0.77).

Conclusions

The findings show that with regards to age, sex and place of residence, self-reported health, life satisfaction, physical and screen-time related siting activities, as well as eating behaviour items of the HBSC questionnaire have a sufficient test–retest reliability to be used in national self-report surveys for Vietnamese adolescents while health complaints items showed borderline reliability.

Is the Health Behavior in School-Aged Survey Questionnaire Reliable and Valid in Assessing Physical Activity and Sedentary Behavior in Young Populations? A Systematic Review

Backgrounds

Using the self-reported questionnaire to assess the levels of physical activity (PA) and sedentary behavior (SB) has been a widely recognized method in public health and epidemiology research fields. The selected items of the Health Behavior in School-aged (HBSC) Survey Questionnaire have been used globally for measurements and assessments in PA and SB of children and adolescents. However, there are no comprehensive and critical reviews to assess the quality of studies on reliability and validity of selected items for PA and SB measurement and assessment derived from the HBSC. Thus, this review aimed to critically assess the quality of those studies and summary evidence for future recommendations.

Methods

A systematic review protocol was used to search potentially eligible studies on assessing reliability and validity of PA and SB measures of the HBSC questionnaire. electronically academic databases were used. The information on the reliability and validity of the PA and SB measures were extracted and evaluated with well-recognized criteria or assessment tools.

Results

After a literature search, six studies were included in this review. The reliability of PA measures of the HBSC questionnaire showed a moderate agreement while the reliability of SB measures showed a great variation across the different items in the different subgroups. The validity of the PA measures had acceptable performance, whereas no studies assess the validity of the SB measures. The included studies all had quality weaknesses on reliability or validity analysis.

Conclusions

The PA and SB measures of the HBSC questionnaires were reliable in assessing PA and SB among adolescents. However, a little evidence showed that PA measures are partially valid in assessing PA, but no evidence confirmed the validity of SB measures. The included studies all had methodological weaknesses in examining the reliability and validity of the PA and SB measures, which should be addressed in the future. Further studies are encouraged to use a more standardized study design to examine the reliability and validity of the PA and SB measures in more young populations.

Weight management recommendations for youth with Down syndrome: Expert recommendations

Youth with Down syndrome (DS) have a higher prevalence of overweight and obesity compared to the general youth population. Due to physiological and cognitive differences observed in youth with DS, weight management recommendations developed for the general population, may not be suitable for youth with DS. However, there are no recent recommendations for weight management in youth with DS. A workgroup of clinicians and researchers with extensive experience working with youth with DS came together to give clinicians and families guidance for weight management in youth with DS. Recommendations were developed by the workgroup via a methodical, deliberative process. After the initial development of the recommendations, they were shared with an expert review panel and caregivers who rated the strength of the recommendation and strength of the evidence. The workgroup moved forward the recommendations which the review panels rated as strong. Eight recommendations were developed which focused on screening for overweight and obesity, screening for health conditions that may impact dietary intake and physical activity, screening for feeding difficulties, setting appropriate recommendations for dietary intake and physical activity, and well as prevention and treatment of overweight and obesity using evidence-based strategies. These recommendations can be implemented by clinicians working with youth with Down syndrome as well as the family, school, and other relevant entities.

Mental Simulation to Promote Exercise Intentions and Behaviors

Mental simulation, which employs specific patterns of imagery, can increase the intention to exercise as well as actual engagement in exercise. The present studies explored the effects of mental simulation on the intention to engage in exercise while regulating emotions. The first study confirmed that mental simulation did promote intentions of participants. The second found that video-primed mental simulation was a more effective method of exercise intention promotion than semantic-primed and image-primed mental simulation. In the third study, it was found that combining process-based and outcome-based mental simulations increased exercise intentions. Positive emotions mediated imagery ability and intention to exercise. The final study found that the mental simulation interventions most effective for exercise adherence were those that balanced the valence of process and outcome components in such a way that a challenging process results in a positive outcome, or a smooth process results in a negative outcome. Each of these results has practical implications for exercise interventions that will be discussed.

Body mass index and physical activity in seven-year-old children whose mothers exercised during pregnancy: follow-up of a multicentre randomised controlled trial

BACKGROUND

There are limited data on long-term outcomes of children whose mothers have followed exercise interventions during pregnancy. The aim of this paper was to investigate whether regular moderate intensity exercise during pregnancy affected the children's body mass index (BMI) and physical activity (PA) at 7 years of age, and determine the relationship between children's and mothers' BMI and PA.

METHODS

This was a follow-up of a multicentre randomised controlled trial, carried out at St. Olavs Hospital, Trondheim University Hospital, and Stavanger University Hospital, Norway (2007-2009 and 2014-2016). Women were randomised to follow a 12-week structured exercise protocol or standard antenatal care during pregnancy. At the 7-year follow-up, parents reported their child's height, weight, and PA. The mothers also reported their own weight and PA. Main outcome variables were BMI, frequency and duration of moderate to vigorous PA (MVPA), and intensity of PA.

RESULTS

A total of 855 women were randomised to exercise (n = 429) or standard antenatal care (n = 426) during pregnancy. At follow-up, 164 (38.2%) children and mothers in the intervention group and 117 (27.5%) in the control group participated. We found no group differences in the children's iso-BMI or PA. Findings were similar when we performed stratified analyses by sex, except boys in the control group spent more time on electrical devices than boys in the intervention group. Subgroup analyses of children of mothers who adhered to the exercise protocol and sensitivity analyses excluding children born preterm, children admitted to the neonatal intensive care unit, and children with diseases or health problems at the 7-year follow-up, did not change the results. Children's BMI, weekly leisure time MVPA and intensity of PA correlated with mothers' BMI, daily exercise, and intensity of exercise.

CONCLUSIONS

Regular moderate intensity exercise during pregnancy did not affect BMI or PA of the children at 7 years. Good maternal health should be encouraged as it may influence the health of the next generation.

TRIAL REGISTRATION

The initial RCT study was registered in ClinicalTrials.gov NCT00476567 .

Risk factors and risk profiles for neck pain in young adults: Prospective analyses from adolescence to young adulthood-The North-Trøndelag Health Study

The objective was to investigate risk factors and risk profiles associated with neck pain in young adults using longitudinal data from the North-Trøndelag Health Study (HUNT). Risk factors were collected from adolescents (13-19 years of age), and neck pain was measured 11 years later. The sample was divided into two: Sample I included all participants (n = 1433), and Sample II (n = 832) included only participants who reported no neck/shoulder pain in adolescence. In multiple regression analyses in Sample I, female sex (OR = 1.9, 95% CI [1.3-2.9]), low physical activity level (OR = 1.6, 95% CI [1.0-2.5]), loneliness (OR = 2.0, 95% CI [1.2-3.5]), headache/migraine (OR = 1.7, 95% CI [1.2-2.6]), back pain (OR = 1.5, 95% CI [1.0-2.4]) and neck/shoulder pain (OR = 2.0, 95% [CI 1.3-3.0]) were associated with neck pain at the 11-year follow-up. Those with a risk profile including all these risk factors had the highest probability of neck pain of 67% in girls and 50% in boys. In Sample II, multiple regression analyses revealed that female sex (OR = 2.2, 95% CI [1.3-3.7]) and perceived low family income (OR = 2.4, 95% CI [1.1-5.1]) were associated with neck pain at the 11-year follow-up. Girls and boys with a perceived low family income had a 29% and 17% higher probability of neck pain than adolescents with a perceived high family income. The risk profiles in both samples showed that co-occurrence of risk factors, such as headache/migraine, neck/shoulder pain, back pain, low physical activity level, loneliness, and perceived low family income cumulatively increased the probability of neck pain in young adulthood. These results underline the importance of taking a broad perspective when studying, treating, and preventing neck pain in adolescents.

Validity, reliability, and calibration of the physical activity unit 7 item screener (PAU-7S) at population scale

BACKGROUND

Validation of self-reported tools, such as physical activity (PA) questionnaires, is crucial. The aim of this study was to determine test-retest reliability, internal consistency, and the concurrent, construct, and predictive validity of the short semi-quantitative Physical Activity Unit 7 item Screener (PAU-7S), using accelerometry as the reference measurement. The effect of linear calibration on PAU-7S validity was tested.

METHODS

A randomized sample of 321 healthy children aged 8-16 years (149 boys, 172 girls) from the nationwide representative PASOS study completed the PAU-7S before and after wearing an accelerometer for at least 7 consecutive days. Weight, height, and waist circumference were measured. Cronbach alpha was calculated for internal consistency. Test-retest reliability was determined by intra-class correlation (ICC). Concurrent validity was assessed by ICC and Spearman correlation coefficient between moderate to vigorous PA (MVPA) derived by the PAU-7S and by accelerometer. Concordance between both methods was analyzed by absolute agreement, weighted kappa, and Bland-Altman statistics. Multiple linear regression models were fitted for construct validity and predictive validity was determined by leave-one-out cross-validation.

RESULTS

The PAU-7S overestimated MVPA by 18%, compared to accelerometers (106.5 ± 77.0 vs 95.2 ± 33.2 min/day, respectively). A Cronbach alpha of 0.76 showed an acceptable internal consistency of the PAU-7S. Test-retest reliability was good (ICC 0.71 p < 0.001). Spearman correlation and ICC coefficients of MVPA derived by the PAU-7S and accelerometers increased from 0.31 to 0.62 and 0.20 to 0.62, respectively, after calibration of the PAU-7S. Between-methods concordance improved from a weighted kappa of 0.24 to 0.50 after calibration. A slight reduction in ICC, from 0.62 to 0.60, yielded good predictive validity. Multiple linear regression models showed an inverse association of MVPA with standardized body mass index (β - 0.162; p < 0.077) and waist to height ratio (β - 0.010; p < 0.014). All validity dimensions were somewhat stronger in boys compared to girls.

CONCLUSION

The PAU-7S shows a good test-retest reliability and acceptable internal consistency. All dimensions of validity increased from poor/fair to moderate/good after calibration. The PAU-7S is a valid instrument for measuring MVPA in children and adolescents.

TRIAL REGISTRATION

Trial registration number ISRCTN34251612 .

Global prevalence of physical activity for children and adolescents; inconsistencies, research gaps, and recommendations: a narrative review

BACKGROUND

One of the strategic actions identified in the Global Action Plan on Physical Activity (PA) 2018-2030 is the enhancement of data systems and capabilities at national levels to support regular population surveillance of PA. Although national and international standardized surveillance of PA among children and adolescents has increased in recent years, challenges for the global surveillance of PA persist. The aims of this paper were to: (i) review, compare, and discuss the methodological inconsistencies in children and adolescents' physical activity prevalence estimates from intercontinental physical activity surveillance initiatives; (ii) identify methodological limitations, surveillance and research gaps.

METHODS

Intercontinental physical activity surveillance initiatives for children and adolescents were identified by experts and through non-systematic literature searches. Prevalence of meeting PA guidelines by country, gender, and age were extracted when available. A tool was created to assess the quality of the included initiatives. Methods and PA prevalence were compared across data/studies and against the methodological/validity/translation differences.

RESULTS

Eight intercontinental initiatives were identified as meeting the selection criteria. Methods and PA definition inconsistencies across and within included initiatives were observed, resulting in different estimated national prevalence of PA, and initiatives contradicting each other's cross-country comparisons. Three findings were consistent across all eight initiatives: insufficient level of PA of children and adolescents across the world; lower levels of PA among girls; and attenuation of PA levels with age. Resource-limited countries, younger children, children and adolescents not attending school, with disability or chronic conditions, and from rural areas were generally under/not represented.

CONCLUSIONS

There are substantial inconsistencies across/within included initiatives, resulting in varying estimates of the PA situation of children and adolescents at the global, regional and national levels. The development of a new PA measurement instrument that would be globally accepted and harmonized is a global health priority to help improve the accuracy and reliability of global surveillance.

Assessing Physical Activity After ACL Injury: Moving Beyond Return to Sport

CONTEXT

Return to sport is widely utilized by sports medicine researchers and clinicians as a primary outcome of interest for successful recovery when working with young patients who have undergone anterior cruciate ligament (ACL) reconstruction (ACLR). While return-to-sport outcomes are effective at tracking progress post-ACLR, they are limited because they do not necessarily capture physical activity (PA) engagement, which is important to maintain knee joint health and reduce the risk of noncommunicable diseases. Therefore, there is a critical need (1) to describe current PA participation and measurement recommendations; (2) to appraise common PA measurement approaches, including patient-reported outcomes and device-based methodologies; and (3) to provide clinical recommendations for future evaluation.

EVIDENCE ACQUISITION

Reports of patient-reported or device-based PA in patients with ACL injury were acquired and summarized based on a PubMed search (2000 through July 2020). Search terms included physical activity OR activity AND anterior cruciate ligament OR ACL.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 5.

RESULTS

We highlight that (1) individuals with ACLR are 2.36 times less likely to meet the US Department of Health and Human Services PA recommendations even when reporting successful return to sport, (2) common patient-reported PA assessments have significant limitations in the data that can be derived, and (3) alternative patient-reported and device-based assessments may provide improved assessment of PA in this patient population.

CONCLUSION

Clinicians and researchers have relied on return to sport status or self-reported PA participation via surveys. These approaches are not consistent with current recommendations for PA assessment and do not allow for comparison with contemporary PA recommendations or guidelines. Return to sport, patient-reported outcome measures, and device-based assessment approaches should be used in complementary manners to comprehensively assess PA participation after ACLR. However, appropriate techniques should be used when assessing PA in adult and adolescent populations.

Sociodemographic Correlates and Mental Health Comorbidities in Adolescents With Social Anxiety: The Young-HUNT3 Study, Norway

Social anxiety is highly prevalent in adolescents and is often associated with great individual suffering and functional impairment. Psychiatric comorbidity is common and further adds to this burden. The purposes of this study were: (1) to describe the occurrence of diagnosed and self-reported social anxiety among 8,199 Norwegian adolescents aged 13–19 years who participated in the population-based Young-HUNT3 study (2006–2008); (2) to examine associations between sociodemographic characteristics and different subgroups of social anxiety; and (3) to describe the psychiatric health comorbidities among adolescents diagnosed with social anxiety disorder (SAD). In total, 388 (5.9%) of the adolescents screened positive for SAD and were invited into a diagnostic interview, performed by professional nurses, using Anxiety Disorders Interview Schedule for DSM IV: child version (ADIS-C) (response rate = 54.6%). A SAD diagnosis was indicated in 106 individuals (50% of the interview subjects), and more than two-thirds of the adolescents diagnosed with SAD had one or more comorbid psychiatric disorders. Higher mean scores of self-reported social anxiety symptoms, poor self-rated health, sleep problems, poor family economic situation, low physical activity, and having sought professional help within the last year were associated with higher odds of being in the screening positive subgroup. Screening positive subjects who did not meet for a diagnostic interview did not differ notably from the rest of the screening positive group in terms of these sociodemographic characteristics. Based on our results and the fact that individuals with social anxiety often fear interview situations, the use of ADIS-C, screening questions and self-reports seem to be sufficient when aiming to identify epidemiologically representative cohorts of adolescents at risk of social anxiety.

Effect of Sex, Body Mass Index and Physical Activity Level on Peak Oxygen Uptake Among 14-19 Years Old Adolescents

The aim was to describe longitudinal trends in peak oxygen uptake (VO_2peak) among 14- to 19-year-old adolescents in Norway, and to examine effects of sex, body mass index (BMI), and physical activity (PA) level on VO_2peak during adolescence. Of 124 invited students from two lower secondary schools in Norway, 116 eighth-grade students (61 boys and 55 girls; 14 years old at baseline) volunteered to participate. The study has a longitudinal design with 6 yearly repeated measures of body height and mass, VO_2peak and PA level. VO_2peak allometrically scaled to body mass raised to the power of 0.67 was measured using a walking or running incremental test on a treadmill, whereas PA level was self-reported. Among 696 possible observations, 555 (79.7%) were valid. Multiple linear regression and linear mixed model analyses were used to examine the associations between age, sex, BMI, PA level and VO_2peak. VO_2peak showed a non-linear pattern from age 14 to 19, with a distinct increase for boys peaking at age 17, while the results provide a flatter and more stable curve for girls. Sex, BMI and PA level together explained 43–71% of the variance in VO_2peak at the different age levels. Sex and PA level contributed independently to explain a significant proportion of the variance in VO_2peak at all measurement occasions, while BMI did not. Adjusted sex differences in VO_2peak increased over time, from 26.5 ml·kg^−0.67·min⁻¹ at age 14 to 55.5 ml·kg^−0.67·min⁻¹ at age 19. The independent contribution from PA level to the variance in VO_2peak increased from age 14 to 16 and then decreased. While PA level explained 32.5% of the total variance in VO_2peak for 16-year-olds, this number was 14% in 19-year-olds. In conclusion, aerobic power showed a non-linear pattern during adolescence, peaking at age 17. Sex and PA level explained a large proportion of the variance in VO_2peak, each of them being an independent contributor to VO_2peak. Aerobic power is linked to improved health and seems to depend largely on sex and PA level in adolescents, emphasizing the importance of maintaining a sufficient PA level during adolescence.

Comparing three screen-based sedentary behaviours' effect upon adolescents' participation in physical activity: The ESSENS study

Background

Literature focusing on the association between sedentary behaviours and physical activity has provided equivocal results and has been dominated by TV viewing as the indicator of sedentary behaviour. There is a need for more studies exploring the association between contemporary screen activities and physical activity among youth.

Methods

A cross-sectional study including 742 adolescents was conducted in 2016. Data were collected at school through an online questionnaire. Regression analyses were used to explore the association between different screen-based sedentary behaviours and participation in physical activity.

Results

The results showed that those with lower (vs higher) time spent on TV/movie streaming and electronic game playing both on weekdays and weekend days had significantly higher odds of participating in physical activity. There were no significant associations between socializing/surfing online both on weekdays and weekend days and physical activity in adjusted models.

Conclusions

TV/movie streaming and electronic game playing during both weekdays and weekend days were significantly inversely related with participating in physical activity. Initiatives aimed at reducing screen-based sedentary activities might result in favourable effects on physical activity levels among adolescents.

Repetitive Head Impact Exposure and Cerebrovascular Function in Adolescent Athletes

The purpose of this study was to determine how subconcussive head impact exposure in high school collision sport student-athletes influenced cerebrovascular function. Transcranial Doppler was used to assess pre- to post-season changes in: (1) resting middle (MCA) and posterior cerebral arteries (PCA), (2) cerebrovascular reactivity (CVR) via breath-holding index (BHI), vasomotor reactivity response (VMRr) and overall MCA response curve, and (3) neurovascular coupling (NVC) via NVC response magnitude and overall PCA response curve. Fifty-three high school-aged athletes (age = 15.8 ± 1.2years, height = 175.8 ± 8.1cm, mass = 69.4 ± 13.5kg) were recruited into two groups (collision vs. non-collision sport). All participants completed a pre-season cerebrovascular function assessment. Following a 4- to 5-month window (118.6 ± 12.2 days), 48 athletes from the original sample (age = 16.0 ± 1.2 years, height = 175.5 ± 8.1 cm, mass = 68.6 ± 4.0 kg) repeated the cerebrovascular assessment. There were no group differences in any cerebrovascular measures at pre-season testing (p > 0.05). At post-season testing, collision sport athletes demonstrated greater positive change in BHI (t₄₄ = -2.21, p = 0.03) while non-collision sport athletes demonstrated greater negative change in the NVC response magnitude to the reading task (t₄₄ = 1.98, p = 0.048), and lower overall PCA response curve to the reading task (F_1,2710 = 101.54, p < 0.001). All other pre- to post-season change values were non-significant (p > 0.05). Our data indicate that single-season changes in cerebrovascular outcomes may differ between collision and non-collision sport athletes. Although the clinical interpretation is still unclear, our study demonstrates that CVR and NVC assessments may be sensitive to the dynamic cerebrovascular changes occurring in adolescent athletes. Future research should continue to assess these outcomes following both subconcussive head impact exposure and throughout the recovery trajectory following concussion.

Feasibility and reliability of the Spanish version of the Youth Activity Profile questionnaire (YAP-Spain) in children and adolescents

Considerable public health efforts across the globe have focused on promoting physical activity (PA) and minimizing sedentary behaviour (SB) in youths. However, it is important to have valid, reliable and feasible methods to assess these behaviours in youths. The purpose of this study was to analyse the feasibility and reliability of the Spanish version of the previously validated Youth Activity Profile questionnaire (YAP) in children and adolescents. The YAP-S is a 15-item self-report instrument designed to capture PA and SB in youths. A total of 604 children (5-12 years old) and 346 adolescents (12-17 years old) filled out the questionnaire twice (14 days apart). Feasibility was evaluated through required time and number of misunderstood questions by participants. The test-retest reliability was examined using the weighted kappa coefficient (κ) and intraclass correlation coefficient. The average time to complete the questionnaire was 28.85 ± 14.28 and 12.24 ± 9.84 minutes in children and adolescents, respectively. No misunderstanding of questions was reported. The questionnaire showed an adequate reliability for activity at school, out-of-school and sedentary behaviours (k = 0.61-0.77; ICC = 0.77-0.89) in children and adolescents. The YAP-S might be considered a feasible and reliable questionnaire for assessing PA and SB in Spanish children and adolescents.

A 10-week exercise intervention can improve work posture but not neck/shoulder symptoms in dental health students: A pilot cohort study

BACKGROUND

Dental workers including dental health students experience a high incidence of neck/shoulder symptoms. However, research into interventions has been scarce and largely focused on tools and technological modifications.

OBJECTIVE

This study investigates the feasibility and benefits of a neck/shoulder exercise intervention on work posture and local symptoms in dental health students.

METHODS

Twenty-three students participated in a 10-week resistance exercise program for 2 minutes daily, 5 days per week. Work posture (evaluated with the Rapid Upper Limb Assessment tool, RULA), muscle strength measures, self-rated symptom severity and function were collected. Feasibility of the intervention was determined with six items scored on a 5-point Likert scale.

RESULTS

The exercise intervention improved: work posture score by 1.88 (95% CI 1.05-2.70, p < 0.01) points on the RULA; isometric maximal strength of neck flexor and extensor muscles by 17.2% (95% CI 6.9-27.6%, p < 0.01) and 23.2% (95% CI 10.2-36.3%, p < 0.01) respectively; and clinical performance (77%). Isometric strength of the shoulder muscles, and symptom severity at the neck/shoulder showed no improvement. Adherence to training was 77%.

CONCLUSION

Ten weeks of exercise was feasible for dental health students, and likely beneficial with improvements in work posture and neck muscle strength.

Obesity in Young Adulthood: The Role of Physical Activity Level, Musculoskeletal Pain, and Psychological Distress in Adolescence (The HUNT-Study)

The global obesity epidemic raises long-term health concerns which underline the importance of preventive efforts. We aimed to investigate individual and combined effects of common health problems in adolescence on the probability of obesity in young adulthood. This prospective population-based study included data from participants in the Nord-Trøndelag Health Study in Norway (Young-HUNT1 (1995–1997), age 13–19, baseline) who participated in HUNT3 as young adults 11 years later (age 23–31). Exposure variables at baseline included self-reported physical activity, musculoskeletal pain, and psychological distress. We examined associations between exposure variables and the main outcome of obesity in young adulthood (BMI ≥ 30 kg/m²) using univariate and multiple logistic regression, stratified by sex. Probabilities of obesity for given combinations of the exposure variables were visualized in risk matrixes. The study sample consisted of 1859 participants (43.6% boys). Higher probabilities of obesity in young adulthood were found across combinations of lower physical activity levels and presence of musculoskeletal pain in adolescence. Additional adverse effects of psychological distress were low. Proactive intervention strategies to promote physical activity and facilitate sports participation for all adolescents, whilst addressing musculoskeletal pain and its potential individual causes, could prove helpful to prevent development of obesity in young adulthood.

Predicting physical activity in a national cohort of children born extremely preterm

Predicting physical activity in a national cohort of children born extremely preterm.

OBJECTIVES

To compare physical activity among school-aged children born extremely preterm or with extremely low birthweight (EP/ELBW) to term-born children, and to identify early predictors for physical inactivity in the EP/ELBW-children.

METHODS

A national cohort born during 1999-2000 at gestational age < 28 weeks or birthweight <1000 g and term-born controls were assessed. EP/ELBW-children without neurodevelopmental disabilities were labeled "healthy". At five years, we examined the EP/ELBW-children's motor, mental and intellectual functioning using the Movement Assessment Battery for Children (MABC), The Strength and Difficulties Questionnaire (SDQ) and The Wechsler Preschool and Primary Scale of Intelligence-revised. At 11 years, the parents reported their children's physical activity (PA) in questionnaires.

RESULTS

Information was obtained from 231/372 EP/ELBW and 57/61 term-born children. At 11 years, EP/ELBW-children had fewer exercise events per week, were less engaged in team sports, had lower endurance, lower sports proficiency, and were less vigorous during PA than term-born children (p < 0.05). Low sports proficiency in the healthy EP/ELBW-children at 11 years was predicted (odds ratio; 95% confidence interval) by abnormal MABC-score (3.0; 1.0 to 8.7), and abnormal SDQ-score (4.0; 1.6 to 10.0) at 5 years. Lower endurance at PA was predicted by abnormal MABC-score (2.6; 1.0 to 6.6), abnormal SDQ-score (3.0; 1.4 to 6.5), and borderline intellectual functioning (4.2; 1.8 to 10.1).

CONCLUSIONS

Eleven-year-old EP/ELBW-children were less physically active than term-born. In healthy EP/ELBW-children, impaired motor coordination, borderline intellectual functioning and behavioral problems at 5 years of age predicted unfavorable PA habits at 11 years.

Calcium-Sensing Receptor Gene Polymorphisms (CASRV1 and CASRV2) and the Physical Activity Level of Men in Lower Silesia, Poland

Calcium-sensing receptors (CASR) are a dimeric family of C-class G-protein-coupled receptors that play a crucial role in bone and mineral metabolism by regulating parathyroid hormone (PTH) secretion, skeletal development, and urinary Ca²⁺ excretion. Genetic factors mainly impact bone mineral density (BMD). However, many variable factors may affect bone health, including physical activity. The aim of our study was to investigate the potential associations between calcium-sensing receptor gene polymorphisms (CASRV1 and CASRV2) and the level of physical activity in adult males from Lower Silesia, a region in the south of Poland. A total of 428 adult male inhabitants of Lower Silesia were included in the study. Their physical activity was evaluated using the International Physical Activity Questionnaire. The CASRV1 (rs 1801725, G>T, A986S) and CASRV2 (rs 761486, T>G, non-coding region) polymorphisms were determined using polymerase chain reaction (PCR) and mini-sequencing. The polymorphisms were identified with GeneScan software ver. 3.1.2. We did not observe any statistically significant differences between the total energy expenditure (total MET) and the CASRV1 and CASRV2 polymorphisms. We did not find any association between the level of physical activity and the frequency of genotypes at the polymorphic locus of the calcium-sensing receptor genes CASRV1 and CASRV2. We found that the number of hours the subjects spent in a sitting position was unrelated to the genotypes at the polymorphic locus of the calcium-sensing receptor gene CASRV1. Based on our studies, we concluded that there were no associations between CASR and physical activity in the men inhabiting Lower Silesia in Poland. Our results do not suggest any influence of the assessed genetic factors in the population variability of the level of physical activity of adults.

Food Environment Typology: Advancing an Expanded Definition, Framework, and Methodological Approach for Improved Characterization of Wild, Cultivated, and Built Food Environments toward Sustainable Diets

The food environment is a critical place in the food system to implement interventions to support sustainable diets and address the global syndemic of obesity, undernutrition, and climate change, because it contains the total scope of options within which consumers make decisions about which foods to acquire and consume. In this paper, we build on existing definitions of the food environment, and provide an expanded definition that includes the parameter of sustainability properties of foods and beverages, in order to integrate linkages between food environments and sustainable diets. We further provide a graphical representation of the food environment using a socio-ecological framework. Next, we provide a typology with descriptions of the different types of food environments that consumers have access to in low-, middle-, and high-income countries including wild, cultivated, and built food environments. We characterize the availability, affordability, convenience, promotion and quality (previously termed desirability), and sustainability properties of food and beverages for each food environment type. Lastly, we identify a methodological approach with potential objective and subjective tools and metrics for measuring the different properties of various types of food environments. The definition, framework, typology, and methodological toolbox presented here are intended to facilitate scholars and practitioners to identify entry points in the food environment for implementing and evaluating interventions that support sustainable diets for enhancing human and planetary health.

Physical Activity Assessment and Counseling in Pediatric Clinical Settings

Physical activity plays an important role in children's cardiovascular health, musculoskeletal health, mental and behavioral health, and physical, social, and cognitive development. Despite the importance in children's lives, pediatricians are unfamiliar with assessment and guidance regarding physical activity in children. With the release of the 2018 Physical Activity Guidelines by the US Department of Health and Human Services, pediatricians play a critical role in encouraging physical activity in children through assessing physical activity and physical literacy; providing guidance toward meeting recommendations by children and their families; advocating for opportunities for physical activity for all children in schools, communities, and hospitals; setting an example and remaining physically active personally; advocating for the use of assessment tools and insurance coverage of physical activity and physical literacy screening; and incorporating physical activity assessment and prescription in medical school curricula.

Physical Activity Is Associated With Better Executive Function in University Students

Introduction: In recent years, the study of the benefits that physical exercise has on brain health has acquired special relevance. In order to implement exercise as an intervention to protect the brain, it is important to have a more clear idea of its effect in the young population. However, few studies have been carried out on these ages. Objective: The main objective of our study was to evaluate the association between physical activity (PA) with memory and executive function, in university students, analyzing the modulatory effect of sex. Methodology: We collected socio-demographic and life habit information, as well as data on the PA that was carried out during the previous week using the international PAquestionnaire short version (IPAQ-SF) questionnaire in 206 university students (mean age 19.55 ± 2.39; 67.5% women). Memory and executive function were assessed using a comprehensive battery of validate cognitive tests. Univariate and multivariate analyses were performed to correlate PA with cognitive tests scores and to evaluate the potential synergistic role of sex. Results: The main finding was that the total amount of PA correlated positively with several tests that evaluated aspects of executive function, specifically Stroop Colors (Pearson's r = 0.17; p = 0.01) and the Stroop Test Color-Word (Pearson's r = 0.15. p = 0.03). These results were adjusted by a large number of possible confounders and modifying variables in a multivariate analysis, like age, sex, academic record, day of the week, and time at which the test was performed. Additionally, we found out that sex had a synergistic effect with PA on the executive test Trail making test-A (TMTA), and in women, this association was stronger than in men. The more PA women reported, the better they performed, that is to say that they took less time to finalize the TMT-A (interaction term between PA and sex: b = -0.0009; p = 0.014). Conclusion: Our study adds evidence of the benefit of PA in cognition in the young population, specifically in the executive inhibitory control, and more significantly in women.

An Updated Systematic Review of Childhood Physical Activity Questionnaires

Background and Objective

This review is an update of a previous review published in 2010, and aims to summarize the available studies on the measurement properties of physical activity questionnaires for young people under the age of 18 years.

Methods

Systematic literature searches were carried out using the online PubMed, EMBASE, and SPORTDiscus databases up to 2018. Articles had to evaluate at least one of the measurement properties of a questionnaire measuring at least the duration or frequency of children’s physical activity, and be published in the English language. The standardized COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used for the quality assessment of the studies.

Results

This review yielded 87 articles on 89 different questionnaires. Within the 87 articles, 162 studies were conducted: 103 studies assessed construct validity, 50 assessed test–retest reliability, and nine assessed measurement error. Of these studies, 38% were of poor methodological quality and 49% of fair methodological quality. A questionnaire with acceptable validity was found only for adolescents, i.e., the Greek version of the 3-Day Physical Activity Record. Questionnaires with acceptable test–retest reliability were found in all age categories, i.e., preschoolers, children, and adolescents.

Conclusion

Unfortunately, no questionnaires were identified with conclusive evidence for both acceptable validity and reliability, partly due to the low methodological quality of the studies. This evidence is urgently needed, as current research and practice are using physical activity questionnaires of unknown validity and reliability. Therefore, recommendations for high-quality studies on measurement properties of physical activity questionnaires were formulated in the discussion.

PROSPERO Registration Number

CRD42016038695.

Electronic supplementary material

The online version of this article (10.1007/s40279-018-0987-0) contains supplementary material, which is available to authorized users.

Physical activity and sport participation among adolescents: associations with mental health in different age groups. Results from the Young-HUNT study: a cross-sectional survey

OBJECTIVES

Knowledge of how physical activity (PA) and sport participation are related to mental health throughout adolescence is scarce. Our objective was to describe PA levels and sport participation in a population-based sample of adolescents, and to explore how they relate to mental health in different age groups.

DESIGN

A population-based cross-sectional study.

SETTING AND PARTICIPANTS

The adolescent part of the Nord-Trøndelag Health Study, a Norwegian population-based health survey, conducted from 2006 to 2008. Of 10 464 invited participants (age 13-19 years), 7619 (73%) participated, of whom 3785 (50%) were boys.

OUTCOME MEASURES

Mental health outcomes included psychological distress assessed using a short version of the Hopkins Symptom Check List Five items, self-esteem assessed using a short version of the Rosenberg Self-Esteem Scale and life satisfaction assessed with a single-item satisfaction with life measure.

METHOD

Logistic regression models were used to estimate the likelihood of psychological distress, low self-esteem and low life satisfaction, according to self-reported PA level and type of sport participation, stratified by gender and school level (junior vs senior high school).

RESULTS

Fewer senior high school students participated in team sports compared with junior high school students (p<0.001). Physically active adolescents and participants in team sports had higher self-esteem and life satisfaction. A high PA level, compared with a low PA level, was associated with reduced odds of psychological distress among senior high school students (OR 0.63, 95% CI 0.46 to 0.86 for girls and OR 0.46, 95% CI 0.27 to 0.79 for boys). Team sport participation was associated with reduced odds of psychological distress in senior high school girls.

CONCLUSION

A high PA level was favourably associated with various dimensions of mental health, especially for adolescents in senior high school. Team sport participation may have a positive impact on mental health and should, therefore, be encouraged.

Tracking physical activity in baccalaureate nursing students in the United States prior to graduation: A longitudinal study

OBJECTIVE

To evaluate changes in physical activity among baccalaureate nursing students over time.

DESIGN

Longitudinal descriptive study.

SETTING

Baccalaureate nursing program at a four-year university in the United States.

PARTICIPANTS

Fifty-two male (n = 4) and female (n = 48) nursing students.

METHODS

At the beginning and end (weeks 1-2 and 15-16) of the three semesters prior to graduation, students completed the International Physical Activity Questionnaire (IPAQ) and their body mass index (BMI) was calculated. Based on the IPAQ, physical activity was calculated as MET-minutes per week of vigorous, moderate, and walking activities, using metabolic equivalents of 8.0 METS for vigorous, 4.0 METS for moderate, and 3.3 METS for walking.

RESULTS

At baseline, students were 21.3 ± 1.4 years old with a BMI of 23.5 ± 2.9 kg/m². BMI increased throughout the study and prior to graduation was 23.9 ± 3.2 kg/m² (p = 0.039). Overall, students maintained high physical activity levels that did not change statistically. Walking was the predominant activity, followed by vigorous and then moderate activity. Walking and vigorous activity displayed opposing patterns. Vigorous activity decreased over the first three measurement periods (p = 0.029), increased for the fourth period, and then decreased again over the last two periods (p = 0.037 compared to baseline). By comparison, walking increased over the first three measurements (p = 0.002) and then decreased again (p = 0.015). When students were grouped by physical activity level (moderate vs. high), there were significant between-group differences in vigorous activity and walking. At baseline and end of study, the moderate activity group participated in 58% and 49% less vigorous activity, and 83% and 45% less walking than the high activity group.

CONCLUSION

In this group of baccalaureate nursing students, overall physical activity did not decline with time. Students participated in sufficient physical activity to promote health, and after graduation, they are likely to provide effective patient counselling regarding healthy lifestyles.

Validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy: A cross-sectional study

OBJECTIVES

The aim of this study was to examine the validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy (CP).

DESIGN

Cross-sectional.

SETTING

Participants were recruited through 8 National Health Service (NHS) trusts, one school, one university and through organisations that provide services for people with disabilities in England.

PARTICIPANTS

Sixty-four, ambulatory young people aged 10-19 years with CP [Gross Motor Function Classification System (GMFCS) levels I-III] participated in this study.

MAIN OUTCOME MEASURE

The IPAQ-SF was administered to participants. Participants were then asked to wear a wGT3X-BT triaxial accelerometer (ActiGraph, Pensacola, FL) for 7 days to objectively assess PA. Time spent in sedentary behaviour, in moderate to vigorous PA (MVPA) and in total PA (TPA) was compared between measures.

RESULTS

Young people with CP self-reported less time in sedentary behaviour and underestimated the time spent in TPA, when compared to accelerometer measurements. Bland-Altman plots demonstrated poor agreement between the measures for MVPA, with upper and lower 95% limits of agreement of -147 to 148.9minute. After adjusting for gender and GMFCS level, age was a predictor of the difference between measures for MVPA (P<0.001) and TPA (P<0.001).

CONCLUSIONS

These findings suggest that the IPAQ-SF is not a valid method of measuring TPA or sedentary behaviour in young people with CP and it is not appropriate for use when assessing an individual's time in MVPA. Therefore, where feasible, an objective measure of PA should be used.

CLINICAL TRIAL REGISTRATION NUMBER

ISRCTN90378161.

Respiratory health and quality of life in young exclusive, habitual smokers - a comparison of waterpipe smokers, cigarette smokers and non-smokers

Purpose

Waterpipe (WP) use has become a global trend in young populations. However, there are few well-controlled studies focusing specifically on the chronic effects of exclusive WP use on young adults’ respiratory health. We sought to compare in young adults the burden of respiratory symptoms in regular WP smokers (WPS) relative to regular cigarette smokers (CS, positive controls) and non-smokers (negative controls); and to evaluate differences in health-related quality of life between the three groups.

Method

We implemented a cross-sectional survey in college campuses across four countries (Egypt, Jordan, Morocco and Oman). Purposive sampling was employed to identify habitual (regular) healthy WPS (smoked 3 or more WP per week for 3 or more years); CS (smoked 5 or more cigarettes daily for 3 or more years); and non-smokers. Respiratory symptoms were assessed using the European Community Respiratory Health Survey and the American Thoracic Society and the Division of Lung Diseases Questionnaire. Health-related quality of life was measured using the Short-Form 12. Demographic, environmental and lifestyle factors also were measured.

Result

The analytic sample included 135 WPS, 303 CS, and 300 non-smokers. Either tobacco group had significantly greater proportions of males than the non-smoker group. A significantly lower proportion of non-smokers (than either tobacco group) was overweight or obese. Average numbers of reported respiratory symptoms were 5.1, 5.8, and 2.9 in WPS, CS, and non-smokers, respectively. In multivariable regressions controlling for environmental exposures, body mass index, and physical activity, WPS and CS exhibited significantly higher rates of respiratory symptoms than non-smokers (1.6 times greater and 1.9 times greater rate of respiratory symptoms than non-smokers, respectively). Non-smokers reported significantly higher scores for general health relative to either WPS or CS.

Conclusion

Relative to their young non-smoking counterparts, young habitual WPS exhibit a significant burden of respiratory symptoms that is comparable to that observed with CS. Young WPS (and CS), despite their age, may be well on their way to developing respiratory disease.

Evaluation of the socially evaluated cold-pressor group test (SECPT-G) in the general population

Background

In stress research, economic instruments for introducing acute stress responses are needed. In this study, we investigated whether the socially evaluated cold-pressor group test (SECPT-G) induces salivary alpha-amylase (sAA) and/or cortisol responses in the general population and whether this is associated with anthropometric, experimental, and lifestyle factors.

Methods

A sample of 91 participants from the general population was recruited. Salivary cortisol and sAA levels were assessed prior to (t₀), immediately after (t₁), and 10 min after the SECPT-G (t₂).

Results

A robust cortisol increase was found immediately after the SECPT-G, which further increased between t₁ and t₂. This was independent of most of the control variables. However, men showed a trend toward higher cortisol increases than women (p = 0.005). No sAA responses were found at all. However, sAA levels were dependent on measurement time point with highest levels between 9 pm and 9:30 pm. Participants who immersed their hands into the ice water for the maximally allowed time of 3 min showed higher sAA levels at all time points than participants who removed their hands from the water earlier.

Conclusions

We conclude that the SECPT-G is a good means of an acute stress test when cortisol—but not necessarily sAA—responses are intended.

Adolescent body composition and associations with body size and growth from birth to late adolescence. The Tromsø study: Fit Futures-A Norwegian longitudinal cohort study

BACKGROUND

Fat and fat-free masses and fat distribution are related to cardiometabolic risk.

OBJECTIVES

to explore how birth weight, childhood body mass index (BMI) and BMI gain were related to adolescent body composition and central obesity.

METHODS

In a population-based longitudinal study, body composition was measured by dual-energy X-ray absorptiometry in 907 Norwegian adolescents (48% girls). Associations between birth weight, BMI categories, and BMI gain were evaluated by fitting linear mixed models and conditional growth models with fat mass index (FMI, kg/m² ), fat-free mass index (FFMI, kg/m² ) standard deviation scores (SDS), and central obesity at 15 to 20 years, as well as change in FMI SDS and FFMI SDS between ages 15 to 17 and 18 to 20 as outcomes.

RESULTS

Birth weight was associated with FFMI in adolescence. Greater BMI gain in childhood, conditioned on prior body size, was associated with higher FMI, FFMI, and central overweight/obesity with the strongest associations seen at age 6 to 16.5 years: FMI SDS: β = 0.67, 95% CI (0.63-0.71), FFMI SDS: 0.46 (0.39, 0.52), in girls, FMI SDS: 0.80 (0.75, 0.86), FFMI SDS: 0.49 (0.43, 0.55), in boys.

CONCLUSIONS

Compared with birth and early childhood, high BMI and greater BMI gain at later ages are strong predictors of higher fat mass and central overweight/obesity at 15 to 20 years of age.

Leisure-time physical activity and participation in organized sports: Changes from 1985 to 2014 in Finland and Norway

Participation in organized sports is a popular and important part of the lives of children and adolescents and is associated with improved psychological and social health, as well as an increased likelihood of meeting physical activity (PA) recommendations. Changes in modern society, including increased car ownership and use of technology and electronic media, have led to an additional focus on the importance of health‐enhancing PA among children and adolescents. The aim of this article was to study the secular changes in self‐reports of participation in organized sports clubs and leisure‐time vigorous physical activity (LVPA), and whether the relationship between participation in organized sports clubs and LVPA has changed from 1985 to 2014. Questionnaire data were collected in two cross‐sectional samples of Finnish and Norwegian 11‐, 13‐ and 15‐year‐olds in 1985/1986 (n = 7137) and 2014 (n = 9218). Overall, participation in organized sports clubs and level of LVPA appears to have changed in the same direction in the two Nordic countries. The proportion of 11‐year‐olds reporting to be participants in organized sports clubs increased from 1985/1986 to 2014. There was an overall increase in self‐reported LVPA. The association between participation in sports clubs and LVPA was stronger in 2014 than in 1985/1986. The findings indicated subgroup differences, in particular with regard to a steeper increase in LVPA and participation in sports clubs among Finnish girls. We suggest that attention should be given to the role of organized sports to better understand secular changes in PA.

Differences in park characteristic preferences for visitation and physical activity among adolescents: A latent class analysis

In order to optimize environmental interventions, the current study aimed to investigate whether there are subgroups with different preferences regarding park characteristics for park visitation and park-based PA among adolescents (12–16 years). Furthermore, we examined whether the identified subgroups differed in socio-demographics, PA behavior, and park use characteristics (e.g. accompaniment to park, usual activities during park visitation, usual transportation to parks). Adolescents (12–16 years) were recruited via randomly selected secondary schools, located in Flanders (Belgium). Class visits were conducted between September and November 2016 and adolescents were asked to complete an online questionnaire. Latent class analyses using Sawtooth Software were used to identify possible subgroups. A final sample of 972 adolescents (mean age 13.3 ± 1.3 years) remained for analyses. Three subgroups of adolescents with similar preferences for park characteristics could be distinguished for both park visitation and park-based PA. Overall, current results indicate that park upkeep was the most important park characteristic for park visitation as well as park-based PA among at risk subgroups (i.e. adolescents with lower overall PA levels, girls, older adolescents,…) followed by the presence of a playground or outdoor fitness equipment. Among the more active adolescents, especially boys visiting the parks together with friends, the presence of a sport field (soccer and basketball) seems to be the best strategy to increase park visitation as well as park-based PA. Current results provide a starting point to advise policy makers and urban planners when designing or renovating parks that investing in good upkeep and maintenance of parks, and the provision of a playground or outdoor fitness equipment might be the best strategy to increase both park visitation and park-based PA among at risk adolescent subgroups.

Test-retest reliability of adolescents' self-reported physical activity item in two consecutive surveys

Background

National monitoring of school-aged physical activity (PA) behaviours is necessary to inform policy makers. The Finnish School-aged Physical Activity (FSPA – LIITU in Finnish) is a physical activity monitoring study, collecting data from young adolescents aged 11 to 15 years through a nationally representative sample. This study included a single self-reported item question on moderate to vigorous intensity physical activity (MVPA) from the preceding seven days. The question is used widely in the WHO Collaborative Cross-National Health Behaviour in School-aged Children (HBSC) study as a measure of meeting international PA recommendations. This study evaluated the test-retest reliability of the aforementioned MVPA item in two consecutive surveys while observing gender and age categorisation differences.

Methods

In this study, Finnish adolescents with mean ages of 11.5y, 13.5y and 15.5y (n = 2752) completed the HBSC and FSPA surveys in two 45 min class periods without a break in 2014. The HBSC survey completion mode was through pen and paper, and the FSPA study through a web-based questionnaire. The same MVPA question appeared in both surveys. Response alternatives (0–7 days per week) were grouped into four, and two categories in the analyses. Cohen’s Kappa and ICC statistics were performed to test the intra-rater test-retest reliability of the measure.

Results

According to Cohen’s Kappa, there was moderate agreement through the use of four (0.503) and two (0.599) categories, however, the proportion of adolescents that met the recommended daily 60 min of MVPA was 8% lower in the FSPA study than in the HBSC study (19% vs 27%). In addition, ICC for MVPA, as continuous variable (0–7 days) had good to excellent reliability (range 0.694–0.765) for boys and girls aged 13 to 15 years, but only fair (0.565) for boys aged 11.

Conclusions

This study demonstrated that single item MVPA item was considered to have acceptable reliability of the measure for monitoring purposes of 13- and 15-year old boys, and 11y-, 13- and 15y-old girls meeting the international PA recommendations. There were differences in the prevalence in daily MVPA due to survey design.

Understanding Youths' Ability to Interpret 3D-Printed Physical Activity Data and Identify Associated Intensity Levels: Mixed-Methods Study

Background

A significant proportion of youth in the United Kingdom fail to meet the recommended 60 minutes of moderate-to-vigorous physical activity every day. One of the major barriers encountered in achieving these physical activity recommendations is the perceived difficulty for youths to interpret physical activity intensity levels and apply them to everyday activities. Personalized physical activity feedback is an important method to educate youths about behaviors and associated outcomes. Recent advances in 3D printing have enabled novel ways of representing physical activity levels through personalized tangible feedback to enhance youths’ understanding of concepts and make data more available in the everyday physical environment rather than on screen.

Objective

The purpose of this research was to elicit youths’ (children and adolescents) interpretations of two age-specific 3D models displaying physical activity and to assess their ability to appropriately align activities to the respective intensity.

Methods

Twelve primary school children (9 boys; mean age 7.8 years; SD 0.4 years) and 12 secondary school adolescents (6 boys; mean age 14.1 years; SD 0.3 years) participated in individual semistructured interviews. Interview questions, in combination with two interactive tasks, focused on youths’ ability to correctly identify physical activity intensities and interpret an age-specific 3D model. Interviews were transcribed verbatim, content was analyzed, and outcomes were represented via tables and diagrammatic pen profiles.

Results

Youths, irrespective of age, demonstrated a poor ability to define moderate-intensity activities. Moreover, children and adolescents demonstrated difficulty in correctly identifying light- and vigorous-intensity activities, respectively. Although youths were able to correctly interpret different components of the age-specific 3D models, children struggled to differentiate physical activity intensities represented in the models.

Conclusions

These findings support the potential use of age-specific 3D models of physical activity to enhance youths’ understanding of the recommended guidelines and associated intensities.

A Prospective Cohort Study on Injuries Among Intensely Physically Active High School Students

BACKGROUND

The leading cause of nonfatal injuries in age group 14-19 is sports injuries. Purpose of the study was to determine the association between intense physical activity and injury and to identify the circumstances and environment in which injuries are most likely to occur.

METHODS

A prospective cohort study included 698 high school students 15-19 years old, divided into those exposed and those unexposed to intense physical activity. The international standard questionnaire about physical activity (International Physical Activity Questionnaire-IPAQ) and the metabolic equivalent task (MET) scores were used.

RESULTS

The risk of injuries was 7 times higher (relative risk [RR]: 7.041; 95% confidence interval [CI]: 6.071, 8.187) and the risk of injuries requiring treatment in health facilities was 15 times higher (RR: 14.717; 95% CI: 10.652, 20.592) in the intensely physically active adolescents. The risk of gaining sports injuries was 11 times higher in the exposed group (RR: 11.212; 95% CI: 9.013, 14.074), with a significantly higher incidence rate (Inc.) among men (82.9 per 100). Most injuries occurred in football (Inc. 4.4 per 1000 hours), volleyball (Inc. 3.9 per 1000 hours), and boxing/kickboxing (Inc. 3.7 per 1000 hours).

CONCLUSIONS

Intensely physically active high school students have a much higher risk of injury, which usually occurs during training or a match.

Comparison of physical activity and body composition in a cohort of children born extremely preterm or with extremely low birth weight to matched term-born controls: a follow-up study

OBJECTIVES

To compare physical activity and body composition in a cohort of children born extremely preterm/extremely low birth weight (EP/ELBW) with term-born (TB) controls.

METHODS

A regional cohort of children born during 1999-2000 at gestational age <28 weeks or with birth weight <1000 g and their individually matched TB controls were examined in 2010-2011. Information on physical activity was obtained from parental questionnaires, and body composition was determined by anthropometry and dual X-ray absorptiometry.

RESULTS

Fifty-seven EP/ELBW and 57 TB controls were included at a mean age of 11.6 years. Compared with the TB children, the EP/ELBW-born children exercised less often (22% vs 44% exercised more than 3 days per week), had lower physical endurance and poorer proficiency in sports and play and were less vigorous during exercise (p<0.05). They also had lower values (mean; 95 % CI) for muscle mass (0.9; 0.3-1.5 kg), total bone mineral density z-score (0.30; 0.13-0.52 units) and fat mass ratio (0.14; 0.06-0.21 units). The association between physical activity and bone mineral and skeletal muscle mass accrual was significantly weaker for the EP/ELBW-born than the TB children.

CONCLUSIONS

The EP/ELBW-born children were less physically active, had signs of an unfavourable body composition with less muscle mass and lower bone mineral density than the TB controls. The association between physical activity and the measures of body composition was weaker in the group of EP/ELBW-born children.