Leisure time computer use and adolescent bone health--findings from the Tromsø Study, Fit Futures: a cross-sectional study

Association between sedentary behavior and bone mass, microstructure and strength in children, adolescents and young adults: a systematic review

Sedentary behavior (SED) research is currently receiving increasing attention in the field of public health. While it has been shown to have negative effects on cardiovascular or metabolic health, there is limited knowledge regarding the relationship between SED and bone health in children, adolescents, and young adults. Thus, the purpose of this review is to investigate the associations between SED and bone health status, specifically bone mass, microstructure, and strength. A comprehensive literature search was conducted across five electronic databases, including EMBASE, PubMed, Medline, Cochrane, Web of Science and CNKI. The inclusion criteria were as follows: healthy participants aged 24 years or younger, with measured SED and measured bone outcomes. The quality of the included articles was assessed using the National Institute of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. After excluding, the final sample included 25 cross-sectional, 9 observational and 2 both cross-sectional and longitudinal studies. Among these, seven were rated as 'high quality', twenty-three were rated as 'moderated quality', and six were rated as 'low quality' according to the quality assessment criteria. After summarizing the evidence, we found no strong evidence to support an association between BMC or BMD and SED, even when considering gender or adjusting for moderate-to-vigorous physical activity (MVPA). However, a strong level of evidence was found indicating a negative relationship between objectively measured SED and cortical bone mineral density (Ct.BMD) in the tibia or stiffness index (SI) in the Calcaneus across all age groups. While the association between adverse bone health outcomes and SED still cannot be confirmed due to insufficient evidence, these findings suggest that bone microstructure and strength may be more sensitive to SED than bone mass. Thus, further evidence is needed to fully understand the connection between sedentary behavior and bone health, particularly regarding the relationship between SED and bone strength.

Potential causal association between leisure sedentary behaviors and osteoporosis: A two-sample Mendelian randomization analysis

Previous observational studies have observed a correlation between sedentary behavior and osteoporosis. However, conclusions from these studies have been contradictory. To explore the potential causal relationship between sedentary behavior and osteoporosis, we conducted a Mendelian randomization analysis. A two-sample Mendelian randomization was adopted to explore the causal relationship of leisure sedentary behavior with osteoporosis. We employed 5 methods to estimate the causal associations between leisure sedentary behavior and osteoporosis. Univariable Mendelian randomization results provided evidence for the causal relationship of the time spent on computer-use with the bone mineral density estimated by heel quantitative ultrasound (eBMD) (inverse variance weighted [IVW]: β (95% confidence interval [CI]) - 0.150 (-0.270 to -0.031), P = .013; weighted median: β (95%CI) - 0.195 (-0.336 to -0.055), P = .006). Similar associations were observed in the driving forearm bone mineral density (FABMD) (IVW: β (95%CI) - 0.933 (-1.860 to -0.007), P = .048) and driving lumbar spine bone mineral density (IVW: β (95%CI) - 0.649 (-1.175 to -0.124), P = .015). However, we did not find a significant causal relationship between the time spent on watching TV and bone mineral density. Research showed that there was a causal relationship between the time spent on computer use and driving time and eBMD, FABMD, and lumbar spine bone mineral density.

Problematic video gaming is negatively associated with bone mineral density in adolescents

Adolescent bone health may be negatively impacted by problematic video gaming (PVG) due to factors such as prolonged screen time, poor sleep quality, and increased depression. Although sedentary behaviors have been linked to decreased bone mass, there is limited research on how PVG impacts bone health. We aimed to evaluate the association between PVG and bone mineral density (BMD) in adolescents by comparing the BMD z-scores of adolescents with and without PVG and by identifying PVG-related risk factors that may affect low BMD scores. This cross-sectional study took place between May 2019 and August 2021 with 110 adolescents who played video games for at least two hours per day. Data on screen time, game genre, tobacco, alcohol, caffeine consumption, and vigorous physical activity status were recorded. PVG was assessed using the Internet Gaming Disorder-Short Form (IGDS9-SF), with scores ≤ 16 comprising the control group and > 16 the PVG group. Sleep quality was assessed by Pittsburgh Sleep Quality Index, and depression was evaluated by Children's Depression Inventory. Dual-energy X-ray absorptiometry measurements of femoral neck and lumbar spine BMD were compared between the two groups. The mean age of the participants was 14.2 ± 1.8 years, and 86.4% were males. The PVG group exhibited lower femoral neck z-scores (p = 0.013) and a higher proportion of adolescents with low femoral neck BMD risk (27.8% vs 9.7%, p = 0.041). Lumber spine z-scores did not differ (p = 0.271). Despite poorer depressive symptoms and sleep quality in the PVG group, they were not associated with low BMD risk (OR 1.02, 95% CI 0.97-1.08, p = 0.398 and OR 1.00, 95% CI 0.87-1.18, p = 0.972, respectively). Among all PVG-related risk factors, video game time (aOR = 1.22, 95% CI = 1.06-1.41, p = 0.006) and vigorous physical activity amount (aOR = 2.86, 95% CI = 0.93-8.76, p = 0.080) showed the strongest associations with femoral neck z-scores.  Conclusion: The results of this study, showing a negative association between PVG and femoral neck BMD in adolescents, underscore the importance evaluating, monitoring, and supporting lower extremity bone health in adolescents with PVG. What is Known: • Adolescents with problematic video gaming are at risk for depression, impaired sleep; sedentary lifestyle; consumption of tobacco, alcohol, and drugs; and high caffeine intake. • These risk factors might lead to compromised bone health. What is New: • Problematic video gaming is associated with the low femoral neck bone mineral density risk in adolescents. • Extended video game time and reduced physical activity are found to be the primary risk factors.

Role of lifestyle factors in mediating the effect of educational attainment on bone mineral density: a Mendelian randomization study

We performed two-step multivariable Mendelian randomization analysis to explore the mediating role of lifestyle factors in educational attainment (EA) and bone mineral density (BMD). Summary statistics from genome-wide association studies of European lineages were used. Coffee intake and processed-meat intake mediated the association between EA and BMD.

PURPOSE

This study aimed to explore the causal relationship between educational attainment (EA) and bone mineral density (BMD), as well as the potential mediating roles of lifestyle factors in the expected EA-BMD relationship. By identifying modifiable lifestyle factors, we hope to provide relevant information to prevent osteoporosis or low BMD in the less educated population.

METHODS

Using summary statistics from genome-wide association studies (GWAS) of major European lineages, one- and two-sample Mendelian randomization (MR) analyses were performed to estimate the association between EA (in the social sciences genetic association consortium (SSGAC) involving 766,345 individuals and in the UK Biobank (UKB) involving 293,723 individuals) and BMD (in the Genetic Factors for Osteoporosis Consortium involving 426,824 individuals selected from the UKB). The EA variable in both consortia were expressed by years of schooling completed. Two-step multivariable MR was used to assess the mediating roles of eight lifestyle-related factors (moderate-to-vigorous physical activity, watching television, computer using, smoking initiation, coffee intake, alcohol intake frequency, tea intake, and processed-meat intake) in the EA and BMD association, and the corresponding mediating proportion was calculated. Meta-analysis was used to present a pooled estimate.

RESULTS

A total of 317 and 73 independent single-nucleotide polymorphisms (SNPs) of GWAS significance (P < 5.0 × 10-8) were selected as instrumental variables (IVs) for EA in the SSGAC and UKB, respectively. A total of 513 SNPs were selected as IVs for the BMD. The results of one- and two-sample MR revealed that the genetically predicted BMD increased by 0.094 and 0.047 g/cm2, respectively, in response to each SD increment of genetically predicted schooling years. Among the eight candidate mediators, coffee intake and processed-meat intake were potential mediators revealed by the two-step multivariable MR analysis, mediating 26.87% and 23.92% of EA's effect on BMD, respectively. Meta-analysis showed consistent findings. Results of sensitivity analysis indicated the robustness of our findings.

CONCLUSION

We elucidated the causal protective effect of EA on BMD and the mediating roles of coffee intake and processed-meat intake. Intervening with these factors can potentially reduce the burden of bone density loss or osteoporotic fractures among the less educated population.

Health literacy, pain-related interference and pain-related distress of patients with musculoskeletal pain

The present study aimed to compare pain-related interference and pain-related distress in patients with musculoskeletal pain and differing levels of health literacy. A cross-sectional study was conducted among 243 patients with chronic musculoskeletal pain. Short Test of Functional Health Literacy in Adults classified the level of health literacy. Outcome measures included pain-related interference (pain intensity and functional limitation) and pain-related distress (psychosocial factors). Analysis of variance methods were used. One hundred twenty-three (50.62%) participants were classified as adequate, 24 (9.88%) as marginal and 96 (39.50%) as inadequate health literacy. Patients with inadequate health literacy had higher values of pain severity compared to the other groups, when controlled for age. The group adequate health literacy showed less kinesiophobia compared to their counterparts. Functional limitations and other psychosocial factors were similar among groups. Pain severity and kinesiophobia had disadvantageous findings in participants with inadequate health literacy. Still, the results of pain severity must be approached cautiously because the differences were observed when controlled for age solely.

Associations of physical activity and screen time with adolescent idiopathic scoliosis

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is the most common type of idiopathic scoliosis, affecting approximately 0.61%-6.15% adolescents worldwide. To date, the results on the relationship between moderate-to-vigorous physical activity (MVPA) and AIS were inconsistent, and the association between screen time (ST) and AIS remained unclear. This study aimed to describe MVPA and ST among adolescents, and to explore the independent and joint associations between PA, ST, and AIS.

METHODS

A frequency-matched case-control study based on the 2021 Chinese School-based Scoliosis Screening Program in Shenzhen city, south China, was conducted. The research involved 494 AIS patients (aged 9-17 years) and 994 sex- and age-matched healthy controls. MVPA and ST were measured using a self-administered questionnaire. Logistic regression models estimated associations between PA, ST, and AIS.

RESULTS

Compared to subjects meeting the recommended 60-min daily of MVPA, adolescents reporting daily MVPA time less than 60 min had 1.76 times higher odds of experiencing AIS (95% CI: 1.32-2.35) and adolescents reporting daily MVPA in inactive status had 2.14 times higher odds of experiencing AIS (95% CI: 1.51-3.03). Moreover, participants reporting ST for 2 hours or more had 3.40 times higher odds of AIS compared with those reporting ST less than 2 hours (95% CI: 2.35-4.93). When compared with the adolescents reporting both ST and MVPA meeting the guidelines recommended times (ST < 2 h and MVPA ≥ 60 min/day), those reporting both ST ≥ 2 h and MVPA in inactive status are 8.84 times more likely to develop AIS (95% CI: 3.99-19.61).

CONCLUSIONS

This study reported that the insufficient MVPA, especially MVPA in inactive status, and excessive ST were risk factors for AIS. Additionally, the joint effects of insufficient MVPA and excessive ST probably increase the risk of AIS.

The influence of specialization and the level of physical activism on leisure options for students of the Faculty of Physical Education and Sports

Leisure activities, their dynamics in ontogenesis and the way of managing the time allocated to them are a topic that is frequently researched. Purpose: to investigate students' attitudes, aiming at aspects related to forms of leisure, depending on specialization and level of physical activism, by applying a questionnaire. Material and method: The research took place in the academic year 2019-2020, on a number of 180 students of the Faculty of Physical Education and Sports in Galați. The differences for the pairs of independent specialty variables (PES / physical education and sport and PT / physical therapy), respectively physical activity (HLPA / high level of physical activity, and LLPA / low level of physical activity were analyzed, by applying the techniques of MANOVA and ANOVA calculation. Results: Multivariate analysis indicates significant effects of the physical activity variable on the items of the questionnaire for leisure budget factors, preferred leisure activities, leisure sports activities, and for the specialty variable significant effects are determined only at leisure sports activities, so the level of physical activism will generate more differences between the opinions expressed compared to the specialization of students. Univariate test results indicate significant F values (P <0.05) for a number of items, with weaker values, dominant for PT and LLPA groups. Sports activities and socializing on the internet (defining variant of young people) are at the top, so they do not exclude each other. Conclusion: the students from the PES and HLPA groups stand out through a better organization of free time, high satisfaction of its capitalization, a greater involvement in the variants of active leisure and superior socialization, and those from the PT and LLPA groups allocate more time to watching on TV and using the internet. Keywords: physical activism, specialization, questionnaire, active and passive leisure options, opinions

A cross-sectional study of the relationship between recreational sporting activity and calcaneal bone density in adolescents and young adults

OBJECTIVE

Childhood and adolescence are critical periods of bone development. Sporting activity is thought to impact peak bone mass acquisition, but most studies have used dual-energy X-ray absorptiometry (DXA) to assess bone health and reported associations between bone mass and elite sporting activity. The objective of this study was instead to assess the relationship between recreational sporting activity (RSA) and another bone assessment, calcaneal quantitative ultrasound (cQUS), in adolescents and young adults.

METHODS

We related recreational sporting activity, assessed through a lifestyle questionnaire, to heel ultrasound bone parameters in a cohort of New Zealand students aged 16-35 years. Complete datasets with data on all relevant confounders (body mass index (BMI), pubertal timing, smoking status, and alcohol consumption) were available for 452 participants. cQUS was performed using a Lunar Achilles EX II machine to obtain bone parameters, broadband ultrasound attenuation (BUA), and speed of sound (SOS); stiffness index (SI) was derived from these measures. All descriptive statistics and statistical analyses were carried out using SPSS Statistics for Macintosh, Version 23.0 (IBM Corp., Armonk, NY, USA). Results are presented as p-values and 95% CI.

RESULTS

Reported lifetime sport participation declined after an individual's mid-teens. Bone cQUS parameters (SI and BUA and T-score) were all positively associated with BMI, and current physical activity (SI, SOS, BUA, T-score, and Z-score) with SI and SOS measures most strongly associated with current high impact and past recreational sporting activity (all p < 0.05).

CONCLUSION

Calcaneal heel ultrasound bone parameters were associated with physical activity, with SI and SOS rather than BUA more strongly related to current and past recreational sporting activity in young New Zealand adults.

Comparison of bone mineral density according to domains of sedentary behavior in children and adolescents

BACKGROUND

Somatic maturation and the age at onset of puberty are closely related to bone mineral density (BMD), and are potential confounders of the associations between physical activity, sedentary behavior (SB) and BMD in adolescents. Thus the aim was compare BMD at different anatomical sites according to different domains of SB.

METHODS

The sample consisted of 88 young people (54 boys and 34 girls; 9.5 ± 1.5 years). The self-reported SB was measured by the time spent on TV, computer, video game and smartphone. BMD at each location and throughout the body was assessed by DEXA. Physical activity was assessed by a questionnaire. The comparison of the different types of BMD sites according to the SB levels for each screen device and the total SB were analyzed by Covariance Analysis (ANCOVA).

RESULTS

Whole-body BMD was higher in young people with low total SB (Total BMD = 0.957 ± 0.042) than in those with moderate (Total BMD = 0.921 ± 0.053) and high SB (Total BMD = 0.929 ± 0.051) (p-value = 0.011). Children and adolescents with low total SB had higher BMD legs (0.965 ± 0.056) than young people with high total SB (BMD legs = 0.877 ± 0.209), but this relationship was attenuated when the analyzes were adjusted for physical activity (p-value = 0.068).

CONCLUSION

Adolescents with high sedentary behavior tend to have lower whole body bone mineral density than those with low sedentary behavior.

THE INFLUENCE OF BODY INDEX MASS ON THE LEISURE TYPES FOR THE STUDENTS OF THE FACULTY OF PHYSICAL EDUCATION AND SPORTS

The study aims to investigate the ways of spending free time for a group of 180 students of the Faculty of Physical Education and Sports in Galati (years 1, 2 and 3 of cycle 1 / bachelor’s degree studies, with an average age of 22.34 ± 5.79 years.), by using a questionnaire-based survey, structured on 4 distinct factors: leisure time budget, causes limiting leisure time, favorite leisure activities and leisure sports activities. The purpose of the research is to determine the perception of students of the Faculty of Physical Education and Sports on how to spend free time and determine differences of opinion, depending on BMI / body mass index, by dividing them into 3 groups (underweight, normal weight or overweight). Results: The analysis of variance (ANOVA) indicates significant influences of the independent variable on the response values for the following items (F <.05): inaccessibility of going out with friends, stress generated by shopping, limiting free time to help others, spending free time with entourage and life partner, spending holidays in the country, etc. Socializing on the internet, physical sports activities, TV, internet and computer games, going out with friends are the preferred options for students, and reading gets low scores. The differences between groups (in most cases insignificant) however, signal that normal weight students watch TV and the Internet the least, but waste more time with commuting and household activities and have high scores when involved in most sports. Overweight people have low scores for time spent on favorite activities, are most dissatisfied with time management, work more overtime, spend less time with those around them, but prefer to spend time with their life partner or alone, have slightly better scores for reading and music auditions, get the lowest scores for involvement in most sports activities, but have high satisfaction generated by physical effort. Underweight students perceive the inaccessibility of going out with friends more strongly, are more affected by difficult homework, have a higher level of stress for reading, but perceive most other activities as less stressful, socialize more on the internet, prefer jogging and cycling / rollerblading as sports activities. Swimming is selected by all groups as indicated for optimizing health and ensuring body harmony, even if its practice is deficient, and contact / combat sports are indicated as the most risky for physical integrity. Keywords: active and passive leisure, lifestyle, physical and mental health, opinions, accessibility

Common social determinants for overweight and obesity, and dental caries among adolescents in Northern Norway: a cross-sectional study from the Tromsø Study Fit Futures cohort

BACKGROUND

Non-communicable general and oral health conditions share common risk factors. Studies investigating common social determinants as risk factors for overweight/obesity and dental caries among the same adolescents are scarce and inconclusive.

METHODS

This cross-sectional study included data from 464 girls and 494 boys from the population-based Tromsø study Fit Futures, which included first-year students attending upper secondary school in 2010-2011 from two municipalities in Northern Norway (1038 participants in total, 93% participation rate). Multivariable binary logistic regression analyses stratified by sex were used to investigate the association between socioeconomic position indicators (adolescent's own study program, parents' education and employment status) and overweight/obesity indicated by body weight and waist circumference, untreated dental caries in dentine, and when these conditions were considered simultaneously.

RESULTS

Boys enrolled in the general studies and sports programs (versus vocational) had lower odds of being overweight/obese (POR 0.42, 95% CI 0.20-0.86 and POR 0.24, 95% CI 0.08-0.73, respectively), of having high waist circumference (POR 0.39, 95% CI 0.21-0.75 and POR 0.25, 95% CI 0.10-0.64, respectively), dental caries (POR 0.57, 95% CI 0.32-0.99 and POR 0.47, 95% CI 0.22-0.98, respectively), and being simultaneously overweight/obese, having high waist circumference and dental caries (POR 0.24, 95% CI 0.07-0.81 and POR 0.11, 95% CI 0.01-0.98, respectively). Girls enrolled in the general studies program (versus vocational) had lower odds of having dental caries (POR 0.50, 95% CI 0.30-0.84).

CONCLUSIONS

Adolescent's own study program was identified to be a common social determinant for overweight/obesity and dental caries among boys. These results support the broader concept of social determinants as common risk factors for general and oral health conditions, and call for common health promotion strategies addressing these common social determinants among adolescents. However, there is a need for more studies to investigate and better understand the influence of social determinants on health conditions among adolescents.

Headache and musculoskeletal pain in school children are associated with uncorrected vision problems and need for glasses: a case-control study

Musculoskeletal pain and headache are leading causes of years lived with disability, and an escalating problem in school children. Children spend increasingly more time reading and using digital screens, and increased near tasks intensify the workload on the precise coordination of the visual and head-stabilizing systems. Even minor vision problems can provoke headache and neck- and shoulder (pericranial) pain. This study investigated the association between headaches, pericranial tenderness, vision problems, and the need for glasses in children. An eye and physical examination was performed in twenty 10–15 year old children presenting to the school health nurse with headache and pericranial pain (pain group), and twenty age-and-gender matched classmates (control group). The results showed that twice as many children in the pain group had uncorrected vision and needed glasses. Most children were hyperopic, and glasses were recommended mainly for near work. Headache and pericranial tenderness were significantly correlated to reduced binocular vision, reduced distance vision, and the need for new glasses. That uncorrected vision problems are related to upper body musculoskeletal symptoms and headache, indicate that all children with these symptoms should have a full eye examination to promote health and academic performance.

Screen Time and Bone Status in Children and Adolescents: A Systematic Review

Introduction: Technological advances over the last 2 decades have led to an increase in the time spent by children and youth engaged in screen-based activities, and growing recognition of deleterious effects on health. In this systematic review of cohort and cross-sectional studies, we assess current data on the relationship between screen time and bone status in children and teenagers. Methods: We searched PUBMED and SCOPUS databases for studies of children and adolescents that assessed screen time and bone status, determined by measuring bone mineral content or density, bone stiffness index, bone speed of sound, bone broadband ultrasound attenuation, or frame index. Searches were limited to studies published between 1900 and 2020, and performed in accordance with Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The studies included were evaluated using the Newcastle-Ottawa quality assessment scale. Results: Ten cohort and cross-sectional studies including pediatric population were selected. The combined study population was 20,420 children/adolescents, of whom 18,444 participated in cross-sectional studies. Four studies assessed the effects of total screen time, seven the consequences of TV viewing time, and six the effects of recreational computer use on bone health. Our findings indicate an inverse association between total and weekly screen time and bone health in children and adolescents. In 57% of the studies included also a negative correlation between television viewing time and bone status was observed, while recreational computer time did not have a significant impact on bone health. According to the only four studies that included dietetic factors, no relevant differences were found between calcium intake and screen time or bone broadband ultrasound attenuation and bone speed of sound. Conclusions: Review of the literature of the past three decades provides strong support for comprehensive education of screen time on bone status. The findings of this systematic review support a negative association between screen time and bone status in children and adolescents, with a different impact when considering the different technological devices. As peak bone mass in adolescents is the strongest predictor of osteoporosis risk, strategies aimed at improving bone health should incorporate conscious use of digital technology.

Screen Time, Age and Sunshine Duration Rather Than Outdoor Activity Time Are Related to Nutritional Vitamin D Status in Children With ASD

Objective: This study aimed to investigate the possible association among vitamin D, screen time and other factors that might affect the concentration of vitamin D in children with autism spectrum disorder (ASD). Methods: In total, 306 children with ASD were recruited, and data, including their age, sex, height, weight, screen time, time of outdoor activity, ASD symptoms [including Autism Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS) and Autism Diagnostic Observation Schedule-Second Edition (ADOS-2)] and vitamin D concentrations, were collected. A multiple linear regression model was used to analyze the factors related to the vitamin D concentration. Results: A multiple linear regression analysis showed that screen time (β = -0.122, P = 0.032), age (β = -0.233, P < 0.001), and blood collection month (reflecting sunshine duration) (β = 0.177, P = 0.004) were statistically significant. The vitamin D concentration in the children with ASD was negatively correlated with screen time and age and positively correlated with sunshine duration. Conclusion: The vitamin D levels in children with ASD are related to electronic screen time, age and sunshine duration. Since age and season are uncontrollable, identifying the length of screen time in children with ASD could provide a basis for the clinical management of their vitamin D nutritional status.

Association between sedentary behavior and bone mass in adolescents

The effects of sedentary behavior on adolescents' bone health are controversial because, even in normal weight individuals, the excessive time spent in some specific types of these behaviors appears to have no negative effect on bone health.

PURPOSE

To analyze the relationship between sedentary behaviors and bone mass in adolescents.

METHODS

One hundred four adolescent boys and girls, aged 10 to 14 years, were divided into normal weight and overweight according to weight status. Specific sedentary behaviors (time spent on the Internet for school and non-school purposes, using the computer, watching television, and playing videogames) were assessed by questionnaire, and the total sedentary behavior time by accelerometry. Bone parameters were collected using X-ray absorptiometry, using total and lumbar bone mineral density (BMD) and total and lumbar bone mineral content (BMC) values.

RESULTS

In both groups, the time spent on the Internet for non-school purposes was positively correlated to the total and lumbar BMD. Also, while in the overweight group, the time spent using the computer was negatively correlated to lumbar BMD, and the time spent on the Internet for non-school purposes was positively correlated to the total and lumbar BMC, and in the normal weight group, the time spent on the Internet for non-school purposes was positively correlated to lumbar BMC.

CONCLUSIONS

Adolescents who spend more time in sedentary behavior, especially using the Internet for non-school purposes, have higher BMD and BMC, while normal weight adolescents who spend more time on the computer have lower BMD.

Cross-sectional and longitudinal associations between physical activity, sedentary behaviour and bone stiffness index across weight status in European children and adolescents

Background

The associations between physical activity (PA), sedentary behaviour (SB) and bone health may be differentially affected by weight status during growth. This study aims to assess the cross-sectional and longitudinal associations between PA, SB and bone stiffness index (SI) in European children and adolescents, taking the weight status into consideration.

Methods

Calcaneus SI was first measured by quantitative ultrasound among children aged 2–9 years old in 2007/08. It was measured again after 2 years in the IDEFICS study and after 6 years in the I. Family study. A sample of 2008 participants with time spent at sports clubs, watching TV and playing computer/games self-reported by questionnaire, and a subsample of 1037 participants with SB, light PA (LPA) and moderate-to-vigorous PA (MVPA) objectively measured using Actigraph accelerometers were included in the analyses. Weight status was defined as thin/normal and overweight/obese according to the extended International Obesity Task Force criteria. Linear mixed-effects models were used to estimate the cross-sectional and longitudinal associations between PA, SB and SI percentiles, stratified by weight status.

Results

The cross-sectional association between weekly duration of watching TV and SI percentiles was negative in thin/normal weight group (β = − 0.35, p = 0.008). However, baseline weekly duration of watching TV (β = − 0.63, p = 0.021) and change after 2 years (β = − 0.63, p = 0.022) as well as the change in weekly duration of playing computer/games after 6 years (β = − 0.75, p = 0.019) were inversely associated with corresponding changes in SI percentiles in overweight/obese group. Change in time spent at sports clubs was positively associated with change in SI percentiles after 2 years (β = 1.28, p = 0.001), with comparable effect sizes across weight status. In the subsample with accelerometer data, we found a positive cross-sectional association between MVPA and SI percentiles in thin/normal weight group. Baseline MVPA predicted changes in SI percentiles after 2 and 6 years in all groups.

Conclusions

Our results suggested the beneficial effect of PA on SI. However, the increasing durations of screen-based SB might be risk factors for SI development, especially in overweight/obese children and adolescents.

Longitudinal changes in body composition and waist circumference by self-reported levels of physical activity in leisure among adolescents: the Tromsø study, Fit Futures

BACKGROUND

It is not clear how physical activity affects body composition in adolescents. Physical activity levels are often reduced during this period, and the relative proportion of body fat mass and lean mass undergo natural changes in growing adolescents. We aimed to examine whether self-reported physical activity in leisure time at baseline or change in activity during follow-up affect changes in four measures of body composition; body mass index (kg/m2), waist circumference, fat mass index (fat mass in kg/m2) and lean mass index (lean mass in kg/m2).

METHODS

We used data from the Tromsø Study Fit Futures, which invited all first year students in upper secondary high school in two municipalities in northern Norway in 2010-2011. They were reexamined in 2012-2013. Longitudinal data was available for 292 boys and 354 girls. We used multiple linear regression analyses to assess whether self-reported level of physical activity in leisure time at baseline predicted changes in body composition, and analysis of covariance to assess the effects of change in level of activity during follow-up on change in body composition. All analyses were performed sex-specific, and a p-value of < 0.05 was considered statistically significant.

RESULTS

There were no associations between self-reported leisure time physical activity in the first year of upper secondary high school and changes in any of the considered measure of body composition after 2 years of follow up, with the exception of waist circumference in boys (p = 0.05). In boys, change in fat mass index differed significantly between groups of activity change (p < 0.01), with boys adopting activity or remaining physically active having less increase in fat mass index than the consistently inactive. In girls, change in lean mass index differed significantly between groups of activity change (p = 0.04), with girls adopting physical activity having the highest increase.

CONCLUSIONS

Self-reported leisure time physical activity does not predict changes in body composition in adolescents after 2 years of follow up. Change in the level of physical activity is associated with change in fat mass index in boys and lean mass index in girls.

Effects of Full Body Exergaming in Virtual Reality on Cardiovascular and Muscular Parameters: Cross-Sectional Experiment

BACKGROUND

In recent years, many studies have associated sedentary behavior in front of screens with health problems in infants, children, and adolescents. Yet options for exergaming-playing video games that require rigorous physical exercise-seem to fall short of the physical activity levels recommended by the World Health Organization.

OBJECTIVE

The purpose of this study was to investigate the effect of a fully immersive virtual reality (VR)-based training system on cardiovascular and muscular parameters of young adults.

METHODS

A cross-sectional experiment design was used to analyze muscle activity (surface electromyography), heart rate, perceived exertion (RPE), cybersickness symptoms, perceived workload, and physical activity enjoyment (PACES) in 33 participants performing two 5-minute flights on a new training device.

RESULTS

Participants' performance of the planking position required to play the game resulted in moderate aerobic intensity (108 [SD 18.69] bpm). Due to the mainly isometric contraction of the dorsal muscle chain (with a mean activation between 20.6% [SD 10.57] and 26.7% [SD 17.39] maximum voluntary isometric contraction), participants described the exercise as a moderate to vigorous activity (RPE 14.6 [SD 1.82]). The majority reported that they enjoyed the exercise (PACES 3.74 [SD 0.16]). However, six participants had to drop out because of cybersickness symptoms and two because of muscle pain due to prior injuries.

CONCLUSIONS

Our findings suggest that fully immersive VR training systems can contribute to muscle-strengthening activities for healthy users. However, the dropout rate highlights the need for technological improvements in both software and hardware. In prevention and therapy, movement quality is a fundamental part of providing effective resistance training that benefits health. Exergaming on a regular basis has the potential to develop strong muscles and a healthy back. It is essential that future VR-based training systems take into account the recommendations of sport and exercise science.

Adverse physiological and psychological effects of screen time on children and adolescents: Literature review and case study

A growing body of literature is associating excessive and addictive use of digital media with physical, psychological, social and neurological adverse consequences. Research is focusing more on mobile devices use, and studies suggest that duration, content, after-dark-use, media type and the number of devices are key components determining screen time effects. Physical health effects: excessive screen time is associated with poor sleep and risk factors for cardiovascular diseases such as high blood pressure, obesity, low HDL cholesterol, poor stress regulation (high sympathetic arousal and cortisol dysregulation), and Insulin Resistance. Other physical health consequences include impaired vision and reduced bone density. Psychological effects: internalizing and externalizing behavior is related to poor sleep. Depressive symptoms and suicidal are associated to screen time induced poor sleep, digital device night use, and mobile phone dependency. ADHD-related behavior was linked to sleep problems, overall screen time, and violent and fast-paced content which activates dopamine and the reward pathways. Early and prolonged exposure to violent content is also linked to risk for antisocial behavior and decreased prosocial behavior. Psychoneurological effects: addictive screen time use decreases social coping and involves craving behavior which resembles substance dependence behavior. Brain structural changes related to cognitive control and emotional regulation are associated with digital media addictive behavior. A case study of a treatment of an ADHD diagnosed 9-year-old boy suggests screen time induced ADHD-related behavior could be inaccurately diagnosed as ADHD. Screen time reduction is effective in decreasing ADHD-related behavior.

CONCLUSIONS

Components crucial for psychophysiological resilience are none-wandering mind (typical of ADHD-related behavior), good social coping and attachment, and good physical health. Excessive digital media use by children and adolescents appears as a major factor which may hamper the formation of sound psychophysiological resilience.

Bone mineral density at the hip and its relation to fat mass and lean mass in adolescents: the Tromsø Study, Fit Futures

Background

Positive association between body weight and bone mass is well established, and the concept of body mass index (BMI) is associated with higher areal bone mineral density (aBMD) and reduced fracture risk. BMI, that comprises both fat mass (FM) and lean mass (LM) may contribute to peak bone mass achievement in different ways. This study explored the influence of body composition in terms of total body LM and FM on hip aBMD-values in adolescence.

Methods

In 2010/2011, 93% of the region’s first-year upper-secondary school students (15–17 years old) in Tromsø, Norway attended the Tromsø Study, Fit Futures. Areal BMD at femoral neck (aBMD_FN) and total hip (aBMD_TH) (g/cm²), total body LM and FM (g) were measured by dual energy X-ray absorptiometry (DXA). Height and weight were measured, and BMI calculated. Lifestyle variables were collected by self-administered questionnaires and interviews, including questions on time spent on leisure time physical activity. Stratified analyses of covariance and regression models included 395 girls and 363 boys. Crude results were adjusted for age, height, sexual maturation, physical activity levels, vitamin D levels, calcium intake, alcohol consumption and smoking habits.

Results

Unadjusted distribution indicated higher aBMD-levels at higher LM-levels in both genders (p < 0.001), but higher aBMD at higher FM-levels were found only in girls (p < 0.018). After multiple adjustments, aBMD_FN-levels in girls were associated by 0.053 g/cm² and 0.032 g/cm² per standard deviation (SD) change in LM and FM (p < 0.001). Corresponding values in boys were 0.072 and 0.025 (p < 0.001). The high LM groups accounted for the highest aBMD-levels, while aBMD-levels at the LM/FM-combinations indicated different patterns in girls compared to boys. The adjusted odds ratio (95% CI) for low levels of aBMD_FN was 6.6 (3.4,13.0) in boys, compared to 2.8 (1.6,4.9) in girls per SD lower LM.

Conclusions

LM and FM should be regarded as strong predictors for bone mass and hence bone strength in adolescents. A gender specific difference indicated that high lean mass is of crucial importance prominently in boys. In adolescents with low lean mass, especially in girls, high fat mass may partially ameliorate the effect of deficient lean mass levels.

Sedentary behaviour and bone health in children, adolescents and young adults: a systematic review

Sedentary behaviour (SB) is increasing in Western societies and some studies suggest a deleterious effect of SB on bone. The aim of this systematic review was to examine the association between SB and bone health in children, adolescents and young adults. Electronic databases (PubMed, MEDLINE, PsycINFO and Science Citation Index) were searched for relevant articles up to January 9, 2017. Studies were included when results on bone health (e.g. strength, mass and structure) and either subjectively (questionnaires) or objectively (accelerometry) measured SB were reported in healthy participants ≤24 years. Two reviewers independently screened titles and abstracts for eligibility, rated methodological quality and extracted data. Seventeen observational studies were included. Several studies that used DXA or quantitative ultrasound suggested that objectively measured SB was negatively associated with lower extremity bone outcomes, such as femoral neck bone mineral density. The magnitude of this negative association was small and independent of moderate-to-vigorous physical activity. In contrast to the lower extremities, there was insufficient evidence for an association of lumbar spine bone outcomes with objectively measured SB. In high-quality studies that used DXA, no association was observed between objectively measured SB and total body bone outcomes. In studies using questionnaires, none of these relationships were observed. Well-designed longitudinal studies, objectively measuring SB, are needed to further unravel the effect of SB, physical activity and their interaction on bone health.

A population-based study of quantitative sensory testing in adolescents with and without chronic pain

Quantitative sensory testing (QST) has been used to characterize pain sensitivity in individuals with and without pain conditions. Research remains limited in pediatric populations, hindering the ability to expand the utility of QST toward its potential application in clinical settings and clinical predictive value. The aims of this study were to examine pain sensitivity using QST in adolescents with chronic pain compared to adolescents without chronic pain and identify predictors of pain sensitivity. A population-based study conducted from 2010 to 2011 provided data on 941 adolescents, 197 were classified as having chronic pain and 744 were classified without chronic pain. Self-reported data on pain characteristics, psychological functioning, and QST responses were examined. The findings revealed lower pressure pain threshold and tolerance on the trapezius (P's = 0.03) in adolescents with chronic pain compared to adolescents without chronic pain, but no differences on heat or cold-pressor pain tasks. Female sex (P's = 0.02) and poorer psychological functioning (P's = 0.02) emerged as significant predictors of greater pain sensitivity across all pain modalities. Exploratory analyses revealed several associations between clinical pain characteristics and QST responses within the chronic pain cohort. Findings from this large pediatric sample provide comprehensive data that could serve as normative data on QST responses in adolescents with and without chronic pain. These findings lay the groundwork toward developing future QST research and study protocols in pediatric populations, taking into consideration sex and psychological distress.

Longitudinal Trajectories of Television Watching Across Childhood and Adolescence Predict Bone Mass at Age 20 Years in the Raine Study

Sedentary behaviors such as watching television (TV) are associated with increased risk of cardiometabolic disease. The effects of TV watching during key developmental stages on skeletal health are uncertain. Hours of TV watching/week were recorded by parental or self-report at 5, 8, 10, 14, 17, and 20 years of age in 1181 members (48% female) of a pregnancy cohort (the Raine Study). Participants were classified into one of three TV-watching trajectories (using latent class analysis): low (consistently <14 h/week; 20.3%), high (consistently ≥14 h/week; 44.4%), or increasing (increased from <14 to ≥14 h/week during adolescence; 35.3%). General linear models tested associations between TV trajectory and bone mineral content (BMC) measured at age 20 years using dual-energy X-ray absorptiometry. After adjustment for height, body mass, physical activity, calcium intake, serum 25-hydroxyvitamin D levels, alcohol, and smoking (all at age 20 years), males in the low TV-watching trajectory had greater BMC for whole body (mean ± SEM, 3338 ± 59 g versus 3111 ± 31 g), legs (612 ± 12 g versus 569 ± 6 g), and arms (234 ± 5 g versus 214 ± 3 g) than those in the high TV-watching trajectory. Differences between low and high TV-watching trajectories were similar for females. BMC in the increasing TV-watching trajectory also differed for both sexes, for example males in the increasing TV-watching trajectory had greater whole-body BMC (3252 ± 38 g) than males in the high TV-watching trajectory (3111 ± 31 g) but less arm BMC (218 ± 3 g) than those in the low TV-watching trajectory (234 ± 5 g). In this community-based cohort, consistently high TV watching during childhood and adolescence independently predicted reduced peak bone mass at age 20 years. Because attainment of optimal peak bone mass is protective against osteoporosis in later life, reducing sedentary time in children may have long-term skeletal benefits. © 2016 American Society for Bone and Mineral Research.