Children's physical activity levels during organised sports practices

Examining associations between physical activity context and children meeting daily physical activity guidelines: the role of outdoor play, sports, and other organized activities

Background

Less than one-quarter of US children meet physical activity (PA) guidelines. Understanding the context in which PA occurs and how these contexts may play a role in meeting PA guidelines is an essential step toward developing effective behavioral interventions. The purpose of this study was to examine associations between PA context (sports participation, participation in other organized physical activities, active travel to school, and outdoor play) and the number of days children met PA guidelines in a representative sample of children living in Texas.

Methods

We analyzed cross-sectional data from a statewide sample of fourth-grade children in Texas who completed the 2019-2020 Texas School Physical Activity and Nutrition (Texas SPAN) survey. The Texas SPAN survey was designed to monitor the statewide prevalence of overweight/obesity among school children and assess habitual self-reported obesity-related behaviors, including diet and PA. Weighted Poisson regression models were employed to examine the associations between PA contexts (sports participation, participation in other organized physical activities, active travel to school, and outdoor play) and the number of days children met PA guidelines, adjusting for sex, race/ethnicity, overweight/obesity, urban-rural status, and economic disadvantage.

Results

A total of 16.7% of fourth-grade children met physical activity guidelines every day during the week (mean age = 9.4 ± 0.6 years; female = 48.7, 51.8% Hispanic, mean days meeting PA guideline = 3.6 ± 2.3 days). One in ten (11.2%) children did not meet daily PA guidelines on any day of the week, and 72.1% met them between 1 and 6 days. Participating in sports (b = 0.22, 95%CI:0.14, 0.30), any other organized physical activities (b=0.13, 95%CI:0.017, 0.19), and playing outdoors 1-3 days (b = 0.25, 95%CI:0.04, 0.46) and 4-7 days in the past week (b = 0.77, 95%CI:0.57, 0.97) was significantly and positively associated with the number of days children met PA guidelines.

Conclusion

Participating in sports, participating in other organized physical activities, and playing outdoors may beneficially influence the number of days children meet PA guidelines. PA programs should consider these contextual factors and investigate how to promote organized activities and outdoor play effectively and appropriately among children.

The Development and Evaluation of Netball-Specific High-Intensity Interval Training Sessions: The Netball-HIIT Study

This two-phase study involved the design, development, and evaluation of netball-specific high-intensity interval training sessions (Netball-HIIT) for use with netballers of varied ages and abilities. In Phase 1 (2020), a systematic analysis of netball GPS data from 30 netball players and gameplay video footage (10 h) was conducted, followed by the design and testing of five 8 min Netball-HIIT sessions involving 100 netball players (age 21 ± 8.44 years; Australia). In Phase 2 (2021), the feasibility and preliminary efficacy of delivering one Netball-HIIT session each week for five weeks was assessed using a two-armed, dose-matched, randomized, controlled feasibility study with netball players (born in 2010) (Netball HIIT n = 15; Netball Knee Program: NKP n = 15). Cardiorespiratory and muscular fitness was assessed at baseline and 6 weeks. Data were analyzed using linear mixed models and Cohen's d effect sizes. Netball-HIIT sessions were highly rated by players, and higher average (139 bpm) and peak heart rates (156 bpm) were detected amongst Netball-HIIT participants (KNP = 127 bpm and 152 bpm). We observed a large effect for cardiorespiratory fitness (+2.4 laps, d = 0.89), and a small to medium effect for muscular fitness (push-ups +1.2, d = 0.49; standing jump +0.8 cm, d = 0.36) in favor of Netball-HIIT, suggesting that coach-led Netball-HIIT may provide a time-efficient and effective training component for use in netball.

Unsupervised Early Detection of Physical Activity Behaviour Changes from Wearable Accelerometer Data

Wearable accelerometers record physical activity with high resolution, potentially capturing the rich details of behaviour changes and habits. Detecting these changes as they emerge is valuable information for any strategy that promotes physical activity and teaches healthy behaviours or habits. Indeed, this offers the opportunity to provide timely feedback and to tailor programmes to each participant's needs, thus helping to promote the adherence to and the effectiveness of the intervention. This article presents and illustrates U-BEHAVED, an unsupervised algorithm that periodically scans step data streamed from activity trackers to detect physical activity behaviour changes to assess whether they may become habitual patterns. Using rolling time windows, current behaviours are compared with recent previous ones, identifying any significant change. If sustained over time, these new behaviours are classified as potentially new habits. We validated this detection algorithm using a physical activity tracker step dataset (N = 12,798) from 79 users. The algorithm detected 80% of behaviour changes of at least 400 steps within the same hour in users with low variability in physical activity, and of 1600 steps in those with high variability. Based on a threshold cadence of approximately 100 steps per minute for standard walking pace, this number of steps would suggest approximately 4 and 16 min of physical activity at moderate-to-vigorous intensity, respectively. The detection rate for new habits was 80% with a minimum threshold of 500 or 1600 steps within the same hour in users with low or high variability, respectively.

Scaling-Up Adolescent High-Intensity Interval Training Programs for Population Health

High-intensity interval training (HIIT) has become a polarizing form of exercise. In this article, we argue that adolescent HIIT programs can have population health impact if they are (i) integrated into existing opportunities, (ii) designed to develop physical literacy, (iii) delivered in an engaging manner, and (iv) guided and supported by an implementation framework that addresses relevant barriers and facilitators.

Interrelationship Between Age, Gender, and Weight Status on Motor Coordination in Italian Children and Early Adolescents Aged 6-13 Years Old

Although numerous evidences reported a negative correlation between motor coordination (MC) and overweight/obesity in children and adolescents, the interrelationship between age, gender, and weight status is still debatable. Hence, the aim of this cross-sectional study was to examine the association between MC and weight status according to age and gender across childhood and early adolescence in a large sample of Italian elementary and middle school students. A number of 1961 Italian school students (1,026 boys, 935 girls) was stratified in three consecutive age groups (6-7, 8-10, and 11-13 years) and four weight status categories (underweight, normal weight, overweight, and obese) according to Cole's body mass index (BMI) cut-off points for children. MC performance was assessed measuring motor quotient (MQ) with the Körperkoordinationstest für Kinder (KTK). Results showed significantly lower MQ levels in children in overweight (OW) and with obesity (OB) in both sexes for all age groups than peers in normal weight (NW), except in 6-7-year-old boys. Girls in OW and with OB had similar MQ levels across all age groups, while younger boys in OW and with OB showed higher MQ levels than older ones (p < 0.05). The 6-7-year-old boys showed better MQ levels than girls peers in NW, OW, and with OB, while 8-10-year-old boys in underweight (UW), NW, and OW; and 11-13-year-old boys only in NW (p < 0.05). No interaction effect was found between age, gender, and weight status on MQ levels. These outcomes showed the negative impact of higher weight status on MC performance according to age and gender, pointing out the importance of planning targeted motor programs that consider these variables to improve MC performance.

Health-Related Quality of Life and Frequency of Physical Activity in Spanish Students Aged 8-14

The study of health-related quality of life (HRQoL) in children and adolescents has important implications in terms of policy, education, and health. Data on the time spent in physical activity (PA) and in sedentary activities in this population are worrying. We aim to analyze possible differences in HRQoL and PA levels between sexes and age groups in Spanish students aged between 8 and 14 years, as well as to assess the relationship between HRQoL and the frequency of PA in this population. A total of 3197 participants (1610 boys and 1587 girls) from 8 to 14 years old were recruited. Mquality and Mapping Child Health Utility instrument (Chu9d) were used as HRQoL indicators. A medium positive association between PA and HRQoL concerning the Spanish school population was found. HRQoL was higher among students aged 8 to 12 than 13 to 14. Moreover, when children start secondary education, both sexes seem to lose the quality of life. Similarly, PA decreases among girls over the years, although it seems to increase among boys. Thus, PA levels and HRQoL are directly associated in Spanish schoolchildren aged between 8 and 14 years. However, this HRQoL decreases in children over the years. Practical implications include the need to support education and physical activity programs to improve HRQoL in children and adolescents.

Seasonal changes in the physical activity levels of youth Gaelic football players

This study quantified changes in physical activity (PA) levels attained by adolescents during Gaelic football (GF) participation across two time points in a season and determined if these changes affected their overall daily PA levels. A total of 130 adolescents (65 females;15.3 ± 1.5 years) wore an activPAL accelerometer to determine total moderate PA (MPA), vigorous PA (VPA) and moderate-to-vigorous PA (MVPA) during a seven-day measurement period, including during GF. The PA measurement was completed at "preseason" (T1) and "in-season" (T2) timepoints. Between T1 and T2, females significantly increased time spent in MVPA daily (p < 0.001, d = 0.95), on Gaelic football days (GFDs) (p = 0.036; d = 0.30), on non-Gaelic football days (NGFDs) (p < 0.001; d = 0.43), and during GF (p < 0.001, d = 0.90). Males did not record any significant changes in PA over time (p > 0.05). At T2, there were no significant differences in time spent in MVPA daily, on GFDs and NGFDs, and during GF between the genders (p > 0.05). The results suggest that the change in daily PA levels by females is a consequence of increased MVPA during GF and reduced PA barriers across the season.

The Influence of the Coach's Autonomy Support and Controlling Behaviours on Motivation and Sport Commitment of Youth Soccer Players

The coach is one of the most influential agents in the sport commitment of youth players. Grounded in self-determination theory (SDT), numerous studies have examined the influence of the coach’s autonomy-supportive behaviours on athletes’ motivation. However, fewer studies have examined the influence of the coach’s controlling behaviours. The aim of this cross-sectional study was to analyse the influence of young soccer players’ perception of their coach’s autonomy-supportive and controlling behaviours on the satisfaction and frustration of their basic psychological needs (BPN) and sport commitment. A total of 203 soccer players (86% boys), aged 10–19 years (M = 14.88; SD = 1.54) participated. Coach autonomy support positively predicted BPN satisfaction which, in turn, positively explained sport commitment. Coach intimidation behaviours positively predicted BPN frustration, which, in turn, negatively explained sport commitment. In cross-relationships, autonomy support negatively explained BPN frustration, while intimidation behaviours and the controlling use of rewards negatively predicted BPN satisfaction. To conclude, these results suggest that it is important for the coach not only to support autonomy, but also to avoid the use of controlling behaviours, especially intimidation and controlling use of rewards, because of their influence on the motivational processes and sport commitment of youth soccer players.

Goldilocks Days: optimising children's time use for health and well-being

BACKGROUND

One size rarely fits all in population health. Differing outcomes may compete for best allocations of time. Among children aged 11-12 years, we aimed to (1) describe optimal 24-hour time use for diverse physical, cognitive/academic and well-being outcomes, (2) pinpoint the 'Goldilocks Day' that optimises all outcomes and (3) develop a tool to customise time-use recommendations.

METHODS

In 2004, the Longitudinal Study of Australian Children recruited a nationally-representative cohort of 5107 infants with biennial follow-up waves. We used data from the cross-sectional Child Health CheckPoint module (2015-2016, n=1874, 11-12 years, 51% males). Time use was from 7-day 24-hour accelerometry. Outcomes included life satisfaction, psychosocial health, depressive symptoms, emotional problems, non-verbal IQ; vocabulary, academic performance, adiposity, fitness, blood pressure, inflammatory biomarkers, bone strength. Relationships between time use and outcomes were modelled using compositional regression.

RESULTS

Optimal daily durations varied widely for different health outcomes (sleep: 8.3-11.4 hours; sedentary: 7.3-12.2 hours; light physical activity: 1.7-5.1 hours; moderate-to-vigorous physical activity (MVPA): 0.3-2.7 hours, all models p≤0.04). In general, days with highest physical activity (predominantly MVPA) and low sedentary time were optimal for physical health, while days with highest sleep and lowest sedentary time were optimal for mental health. Days with highest sedentary time and lowest physical activity were optimal for cognitive health. The overall Goldilocks Day had 10 hours 21 min sleep, 9 hours 44 min sedentary time, 2 hours 26 min light physical activity and 1 hour 29 min MVPA. Our interactive interface allows personalisation of Goldilocks Days to an individual's outcome priorities.

CONCLUSION

'Goldilocks Days' necessitate compromises based on hierarchies of priorities for health, social and economic outcomes.

Objective Assessment of Physical Activity and Associated Contexts During High School Sport Practices

Background: Organized sports provide children and adolescents with opportunities to achieve recommended amounts of moderate to vigorous physical activity (MVPA), and schools are a primary setting for sports programs. The main aims of this study were to examine participant physical activity (PA) levels during the most popular high school sports in the United States and to assess the influences of practice contextual factors on PA levels. Methods: Participant PA and its contexts were assessed during practices for the 10 most popular girls' and boys' high school sports in the United States. Data were obtained during 598 practice sessions in 12 schools in North Carolina using a validated direct observation instrument (System for Observing Fitness Instruction Time (SOFIT). A regression model was applied to understand the association between sport context and athletes' PA. Results: Overall, athletes were observed engaging in MVPA 60% of practice time. MVPA varied among sports and levels were highly influenced by practice contexts. Among girls' sports, cross country and soccer practices provided the highest proportion of MVPA and MVPA percent during boys' practice sessions was highest during cross country and track and field. Practice contexts were associated with MVPA accrual with time allocated for gameplay and fitness activities associated with the highest levels of PA. Conclusions: The results contribute to an understanding of which sports and how their practices are conducted facilitate increased PA. Findings indicate athletes accrue substantial amounts of PA during high school practices, but that it varies from sport to sport. As well, the context that characterizes sport practices is a significant determinant in how much PA occurs. Most sports that emphasized game simulation, fitness, and skill development drills had higher levels of MVPA. Given the length and frequency of practices and how the content is delivered, we can accurately predict how much PA athletes are likely to achieve during a given sport season. The findings from this study demonstrate that sport can make a useful, if not sufficient role in helping high school athletes reach recommended PA levels. PA engagement can be optimized by attending to the management of contexts surrounding the sports.

Balancing time use for children's fitness and adiposity: Evidence to inform 24-hour guidelines for sleep, sedentary time and physical activity

PURPOSE

Daily time spent on one activity cannot change without compensatory changes in others, which themselves may impact on health outcomes. Optimal daily activity combinations may differ across outcomes. We estimated optimal daily activity durations for the highest fitness and lowest adiposity.

METHODS

Cross-sectional Child Health CheckPoint data (1182 11-12-year-olds; 51% boys) from the population-based Longitudinal Study of Australian Children were used. Daily activity composition (sleep, sedentary time, light physical activity [LPA], moderate-to-vigorous physical activity [MVPA]) was from 8-day, 24-hour accelerometry. We created composite outcomes for fitness (VO2max; standing long jump) and adiposity (waist-to-height ratio; body mass index; fat-to-fat-free log-ratio). Adjusted compositional models regressed activity log-ratios against each outcome. Best activity compositions (optimal time-use zones) were plotted in quaternary tetrahedrons; the overall optimal time-use composition was the center of the overlapping area.

RESULTS

Time-use composition was associated with fitness and adiposity (all measures p<0.001). Optimal time use differed for fitness and adiposity. While both maximized MVPA and minimized sedentary time, optimal fitness days had higher LPA (3.4 h) and shorter sleep (8.25 h), but optimal adiposity days had lower LPA (1.0 h) and longer sleep (10.9 h). Balancing both outcomes, the overall optimal time-use composition was (mean [range]): 10.2 [9.5; 10.5] h sleep, 9.9 [8.8; 11.2] h sedentary time, 2.4 [1.8; 3.2] h LPA and 1.5 [1.5; 1.5] h MVPA.

CONCLUSION

Optimal time use for children's fitness and adiposity involves trade-offs. To best balance both outcomes, estimated activity durations for sleep and LPA align with, but for MVPA exceed, 24-h guidelines.

Physical activity and sedentary time of youth in structured settings: a systematic review and meta-analysis

BACKGROUND

Structured settings, such as school, childcare, afterschool programs, summer camps, and physical activity/sport programs are crucial to promoting physical activity (PA) opportunities and reducing sedentary (ST) for children and adolescents. However, little is known about how much PA and ST children and adolescents accumulate in structured settings. The aim of this study is to conduct a systematic review and meta-analysis of the absolute amount of time youth spend physically active and sedentary in different structured settings (Prospero number: 42018111804).

METHODS

Observational and experimental/quasi-experimental studies (baseline data only) with full-text available, written in English and published in a peer-reviewed journal, reporting the total amount of objectively measured PA (light, moderate, vigorous, and/or total physical activity) and/or time spent ST during structured settings among youth (3 to 18 years) were eligible. Adjusted meta-analysis was conducted to estimate the pooled mean of time spent in PA and ST, by settings and sex.

RESULTS

A total of 187 studies (childcare n=60; school n=91; afterschool programs n=14; summer camp n=4; and Physical activity/ sport programs n=18) from 30 countries (47.9% United States), representing 74,870 youth (mean age 8.6 years old) were included. Overall, there was a high variation between studies in outcomes and settings. The meta-analyses revealed, on average, youth spend 221.8 minutes (36.7 min/hour) in ST and 32.1 minutes (5.1 min/hour) in MVPA during childcare hours, and 223.9 minutes (36.7min/hour) in ST and 27.8 min (4.4 min/hour) in MVPA at school. Relatively, youth are engaged in more MVPA in afterschool programs (11.7 min/hour), PA/ sport programs (20.9 min/hour), and summer camps (6.4 min/hour), when compared to childcare and school.

CONCLUSION

Total PA accumulated during childcare and MVPA accumulated during schools hours were close to recommendations, despite high proportion of ST. Afterschool programs, summer camp and PA/ sport programs are important settings that can contribute to daily PA and reduced ST. Ensuring all youth have access to these structured settings may be an important step forward for public health.

The "Goldilocks Day" for Children's Skeletal Health: Compositional Data Analysis of 24-Hour Activity Behaviors

Optimization of children's activity behaviors for skeletal health is a key public health priority, yet it is unknown how many hours of moderate to vigorous physical activity (MVPA), light physical activity (LPA), sedentary behavior, or sleep constitute the best day-the "Goldilocks Day"-for children's bone structure and function. To describe the best day for children's skeletal health, we used data from the cross-sectional Child Health CheckPoint. Included participants (n = 804, aged 10.7 to 12.9 years, 50% male) underwent tibial peripheral quantitative CT to assesses cross-sectional area, trabecular and cortical density, periosteal and endosteal circumference, polar moment of inertia, and polar stress-strain index. Average daily time-use composition (MVPA, LPA, sedentary time, and sleep) was assessed through 8-day, 24-hour accelerometry. Skeletal outcomes were regressed against time-use compositions expressed as isometric log-ratios (with quadratic terms where indicated), adjusted for sex, age, pubertal status, and socioeconomic position. The models were used to estimate optimal time-use compositions (associated with best 5% of each skeletal outcome), which were plotted in three-dimensional quaternary figures. The center of the overlapping area was considered the Goldilocks Day for skeletal health. Children's time-use composition was associated with all skeletal measures (all p ≤ 0.001) except cross-sectional area (p = 0.72). Days with more sleep and MVPA, less sedentary time, and moderate LPA were beneficially associated with skeletal measures, except cortical density, which was adversely associated. The Goldilocks daily time-use composition for overall skeletal health was center (range): 10.9 (10.5 to 11.5) hours sleep; 8.2 (7.8 to 8.8) hours sedentary time; 3.4 (2.8 to 4.2) hours LPA, and 1.5 (1.3 to 1.5) hours MVPA. Estimated optimal sleep duration is consistent with current international guidelines (9 to 11 hours), while estimated optimal MVPA exceeds recommendations of at least 60 min/d. This first study to describe optimal durations of daily activities for children's skeletal health provides evidence to underpin guidelines. © 2020 American Society for Bone and Mineral Research (ASBMR).

From secondary school to university: associations between sport participation and total and domain-specific sedentary behaviours in Spanish students

Effective ways to reduce sedentary behaviour in adolescents are needed to mitigate the risk of chronic disease and poor mental health. Organised sport participation is the most practiced physical activity during adolescence. However, the influence sport participation has on sedentary behaviours remains unclear. This study investigated the associations between sport participation, total and domain-specific sedentary behaviour and physical activity during the transition from secondary school to university. A 3-year longitudinal survey followed Spanish secondary school students (n = 113) to their first year of university. Generalized linear models, adjusted by gender and year, assessed the relationships between sport participation, total and domain-specific sedentary behaviour and physical activity. Compared with non-sport participants, teenagers who played individual sports from baseline during secondary school spent significantly less total time sitting (- 110.5 min/day at weekends), watching television (- 18.7 min/day at weekends) or using the computer for leisure (- 37.4 min/day weekdays). Those who played team sports from baseline at secondary school spent less time sitting (- 126.4 min/day at weekends) or socialising (- 37 min/day at weekends)Conclusion: From secondary school to university, sport participation-based interventions might be an effective strategy to reduce sitting time spent on some domain-specific behaviours. Promoting sports could reduce the rise of sedentary behaviour during adolescence, a stage where sedentary behaviour evolves. What is Known: • Sitting too much and for too long is an important risk factor during adolescence. • Replacing adolescent's sedentary time with moderate-to-vigorous physical activity has been associated with a better quality of life. What is New: • Playing sport is associated with spending less time in total SB on the transition from high school to college. • Not all SB domains are linked to sport participation with associations differing from whether participants played individual or team sports.

An Examination of Parent-Reported Facilitators and Barriers to Organized Physical Activity Engagement for Youth With Neurodevelopmental Disorders, Physical, and Medical Conditions

Organized physical activity (OPA) is an important contributor to physical, social, and emotional health and well-being; however, young people with disabilities are participating at lower rates than their peers without disabilities. This study aimed to (1) compare facilitators and barriers to OPA for young people with disabilities who currently do and do not participate in OPA and (2) to assess whether groups differed in the type of internal and external assets they reported. Parents of 218 young people (41% with a primary diagnosis of autism spectrum disorder) with a diverse representation of disabilities completed an online survey. Young people were categorized as either participants in OPA (n = 131) or non-participants (n = 87) by parent report. Non-participation was significantly predicted by the barrier “there are no activities my child enjoys” and by a lack of children’s motivation and happiness during OPA. Significant internal assets differentiating participants from non-participants were the ability to understand simple instructions, love of sport, and meeting physical activity guidelines. Significant external assets were parent and sibling participation in OPA, school type, and household income. The findings from this study have important implications for the design of public health interventions that aim to promote OPA in young people with disabilities, highlighting the need to make activities enjoyable, promote participation of siblings and parents, and support low-income families to participate.

Ten Research Priorities Related to Youth Sport, Physical Activity, and Health

Background: Sport has been identified as one of the 7 best investments for increasing physical activity levels across the life span. Several questions remain on how to effectively utilize youth sport as a strategy for increasing physical activity and improving health in youth. The purpose of this paper is to identify the main research priorities in the areas of youth sport and physical activity for health.Methods: An international expert panel was convened, selected to cover a wide spectrum of topics related to youth sport. The group developed a draft set of potential research priorities, and relevant research was scoped. Through an iterative process, the group reached consensus on the top 10 research priorities.Results: The 10 research priorities were identified related to sport participation rates, physical activity from sport, the contribution of sport to health, and the overall return on investment from youth sport. For each research priority, the current evidence is summarized, key research gaps are noted, and immediate research needs are suggested.Conclusion: The identified research priorities are intended to guide researchers, policymakers, and practitioners to increase the evidence base on which to base the design, delivery, and policies of youth sport programs to deliver health benefits.

Isotemporal substitution of sedentary behavior for physical activity on cardiorespiratory fitness in children and adolescents

Both sedentary behavior (SB) and physical activity (PA) are associated with cardiorespiratory fitness (CRF) and independent of each other. Due to the limited time during school for children and adolescents, it is necessary to explore the isotemporal substitution of SB for PA on CRF.A total 536 eligible participants selected from the 7 traditional administrative regions of China were included in this study. The outcome was CRF, determined using a 20-meter shuttle run test, and exposures were SB, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) measured with accelerometers. We analyzed the cross-sectional associations of substituting SB with LPA, MVPA, and combinations of LPA and MVPA with CRF, using an isotemporal substitution model.Reallocating SB into MVPA was associated with higher CRF for male (P < .01) and female (P < .01) children and female adolescents (P < .05). In the mixed redistribution, the ratio of LPA to MVPA for male children and female adolescents started from 16:4 and 14:6, respectively, tended toward improvements in CRF. For female children, regardless of the ratio of LPA to MVPA, it was always associated with higher CRF.Reallocating SB into MVPA isotemporally was positively associated with CRF for male and female children and female adolescents but not for male adolescents. MVPA is the key factor to improve CRF when combinations of LPA and MVPA replace SB. The combined approach can provide basis for the selection of target and monitoring variables in intervention studies, and has more flexible choices for improving CRF that are more consistent with the daily PA habits of children and adolescents.

The physical activity of children and adolescents in Germany 2003-2017: The MoMo-study

With digitalization and virtual entertainment being the megatrends of the 21st century, there is reasonable concern about the role of physical activity (PA) in the daily life of children and adolescents. To identify risk-groups with insufficient PA and to guide interventions, continuous and representative tracking of PA is crucial. In this paper, representative PA data of children and adolescents from the Motorik-Modul (MoMo) baseline study (2003-2006, N = 4,528) is compared to those of Wave 2 (2014-2017, N = 3,708). Participants aged 4-17 were drawn out of 167 sample points in Germany and the data was weighted to ensure representativeness for Germany. Organized (sports clubs and schools) and unorganized (unorganized sports and playing outside) PA was measured by questionnaire and stratified by sex, age, and socioeconomic status. Contrary to common expectation, overall PA remained stable among youths in the past ten years, however, there is an ongoing trend towards organized forms of PA at the expense of unorganized sports and playing outside. Besides different trends in settings, there is inequality in PA distribution among socioeconomic status and gender, unequally pronounced in different settings.

Relationship between Health-Related Quality of Life and Physical Activity in Children with Hyperactivity

The main purpose of this paper was to evaluate the relationship between health-related quality of life (HRQoL) and the frequency of physical activity in Spanish children aged 8 to 14 years with attention deficit hyperactivity disorder (ADHD). Sample selection was performed using the data obtained from the children’s questionnaire of the National Health Survey of Spain 2017 that is carried out with the children’s parents, and that had an initial size of 6106 participants. After the application of the inclusion and exclusion criteria, the sample size was reduced to 496 subjects. Results show significant differences between the different levels of physical activity frequency, as well as a positive correlation of the average between HRQoL and ADHD. In conclusion, the practice of physical activity may contribute to the improvement of HRQoL in children with ADHD, possibly achieving greater benefits at higher levels of physical activity practice.

The participation in organised sport doubles the odds of meeting physical activity recommendations in 7-12-year-old children

The purpose of this study was to determine the contributing role of organised sport participation to daily physical activity (PA) and to describe the PA during training. Children aged 7-12 wore the accelerometer for 1 week. Children with activity data for a minimum of 5 days were included in the analysis (n = 492). Evenson cut-points were used to extract PA data for whole day and training sessions. Compliance with PA recommendations was assessed with two methods - weekly average and daily data. More than half (52.5%) of the children participated in an organised sport at least once a week. Participation in organised sport three or more times a week increased the odds of meeting PA recommendations (average method: OR = 4.02, 95% CI: 1.98-8.19, p < 0.001, days method: OR = 2.82, 95% CI: 1.35-5.88, p = 0.006). On average, children acquired 23.3 ± 15.3 min of moderate to vigorous PA (MVPA) during trainings, while boys accrued more MVPA minutes compared to girls (β = 5.2, 95% CI: 2.4-8.0) and the training time MVPA decreased with age (β = -1.0, 95% CI: -1.9 to -0.1), respectively. Each additional MVPA minute during training increased daily MVPA by 1.3 min (95% CI: 1.1-1.5). On days with training children accumulated 24.9 (95% CI: 21.8-28.0) more MVPA minutes compared to days without training. In conclusion, these findings highlight the importance of organised sport in supporting the PA levels of children. However, participation in the organised sport only is not sufficient to meet PA recommendations, and therefore, PA should be supported throughout the day.

Physical activity and sedentary activity: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To describe the epidemiology and parent-child concordance of objectively measured physical activity in a population-based sample of Australian parent-child dyads.

DESIGN

Cross-sectional study (Child Health CheckPoint) nested within the Longitudinal Study of Australian Children.

SETTING

Assessment centres in seven Australian cities and eight regional towns or home visits; February 2015-March 2016.

PARTICIPANTS

Of all CheckPoint families (n=1874), 1261 children (50% girls) and 1358 parent (88% mothers) provided objectively measured activity data, comprising 1077 parent-child dyads.

OUTCOME MEASURES

Activity behaviour was assessed by GENEActiv accelerometer. Duration of moderate-to-vigorous physical activity (MVPA) and vigorous physical activity and sedentary behaviour (SB) were derived using Cobra custom software, along with MVPA/SB fragmentation and mean daily activity. Pearson's correlation coefficients and linear regression estimated parent-child concordance. Survey weights and methods accounted for the complex sample design and clustering.

RESULTS

Although parents had average lower accelerometry counts than children (mean [SD] 209 [46] vs 284 [71] g.min), 93% of parents met MVPA daily duration guidelines on published cutpoints (mean [SD] 125 [63] min/day MVPA), compared with only 15% of children (mean 32 [27] min). Parents showed less daily SB duration (parents: 540 [101], children: 681 [69] minutes) and less fragmented accumulation of MVPA (parents: α=1.85, children: α=2.00). Parent-child correlation coefficients were 0.16 (95% CI 0.11 to 0.22) for MVPA duration, 0.10 (95% CI 0.04 to 0.16) for MVPA fragmentation, 0.16 (95% CI 0.11 to 0.22) for SB duration and 0.18 (95% CI 0.12 to 0.23) for SB fragmentation.

CONCLUSIONS

Standardised cutpoints are needed for objective activity measures to inform activity guidelines across the lifecourse. This may reflect large amounts of time in non-shared environments (school and work).

Is sport enough? Contribution of sport to overall moderate- to vigorous-intensity physical activity among adolescents

OBJECTIVES

This study examined the contribution of sports participation to overall moderate-to-vigorous physical activity (MVPA) among adolescents, and explored potential moderators.

DESIGN

Cross-sectional observational study using survey and accelerometry data drawn from the NEighbourhood Activity in Youth (NEArbY) study.

METHODS

Adolescents (n=358) were recruited from secondary schools in Melbourne, Australia. Average min/day in MVPA was assessed using accelerometry. Participants self-reported sports participation (number of teams, type, frequency, and months of participation). Regression models determined the percent variance in MVPA explained by the sport variables, adjusted for wear time, age and sex, and accounting for clustering at the school level. Additional analyses tested if age, sex, body mass index (BMI), and socioeconomic status (SES) moderated relationships between sport variables and MVPA.

RESULTS

Participants (mean 15.3 years, 59% female) spent a mean (SD) of 68.6 (27.4) min/day in MVPA and 50% reported participating in any sport. Those who participated in sport did so 3.4 times/week on average and accumulated 7min/day of MVPA more than those who did no sport. For each additional sport participated in, on average, there were approximately 5 additional min/day of MVPA. The number and frequency of sports participation explained 3.2% and 3.8% of the variance in MVPA respectively. Participation in field hockey and gymnastics explained 2.2% and 3.6% of the variance in MVPA, respectively. There were no moderating effects.

CONCLUSIONS

Sport appears to make a very small contribution to adolescents' average daily physical activity. Effectiveness of approaches to increasing youth population levels of physical activity via sports participation needs to be tested.

A source of systematic bias in self-reported physical activity: The cutpoint bias hypothesis

OBJECTIVES

Estimates of adults' moderate-to-vigorous physical activity (MVPA) based on self-report are generally higher than estimates derived from criterion measures. This study examines a possible explanation for part of this discrepancy: the cutpoint bias hypothesis. This hypothesis proposes that inter- and intra-individual variability in energy expenditure, combined with the fact that adults perform a high proportion of daily activities at or just above the traditional 3 MET cutpoint, result in systematic over-estimates of MVPA.

DESIGN

Cross-sectional.

METHODS

Time-use recalls (n = 6862) were collected using the Multimedia Activity Recall for Children and Adults from 2210 adults (1215 female, age 16-93 years) from 16 studies conducted in Australia and New Zealand between 2008-2017. Minutes spent in MVPA were estimated using models with varying levels of intra- and inter-individual (total variability) Unadjusted (0% total variability), Low (11.9%), Best Guess (20.7%), and High (30.0%).

RESULTS

In the Unadjusted model, participants accumulated an average of 129 (standard deviation 127) min/day of MVPA. Estimated MVPA was 98 (110), 99 (107) and 108 (107) min/day in the Low, Best Guess and High variability models, respectively, with intra-class correlation coefficients with the Unadjusted model ranging from 0.78 to 0.83.

CONCLUSIONS

These findings support the hypothesis of a cutpoint bias, which probably contributes to the large disparities seen between self-reported and criterion measures of MVPA. Future studies are needed to confirm these findings using other self-report instruments and in other populations.

Adolescent idiopathic scoliosis for the primary care physician: frequently asked questions

PURPOSE OF REVIEW

Provide primary care physicians with the best available evidence to support answers to frequently asked questions by caregivers of patients with adolescent idiopathic scoliosis (AIS).

RECENT FINDINGS

A review of best available evidence shows that schoolbag design and weight are not associated with higher odds of developing AIS. However, patients with AIS are more prone to balance problems with asymmetric backpack carrying and with rising weights. In patients with AIS, the backpack should be worn in a symmetric way and should never exceed 10% of the child's body weight. Although no relationship was found between systematic exercising in general and development of AIS, classical ballet and professional swimming in skeletally immature adolescents were associated to higher odds of having AIS. Since AIS affects adolescent girls mainly, women health issues are of paramount importance in this disease. Except for limited sexual activity and higher need for infertility treatment, patients with AIS perform similar to controls in marriage rates, age at first pregnancy, gestational age, offspring, labor and delivery. Best available evidence shows that adults with AIS diagnosed during adolescence have similar physical activity level compared with controls. In patients with AIS, adults with surgically treated idiopathic scoliosis have slightly lower physical activity level than previously braced and untreated patients.

SUMMARY

Although schoolbag weight isn't associated with higher odds of developing AIS, classical ballet and professional swimming in adolescents are. Except for limited sexual activity, patients with AIS perform similar to controls in remaining women health issues. Adults with AIS diagnosed during adolescence have similar physical activity level compared with controls.

Organized Sports and Physical Activities as Sole Influencers of Fitness: The Homeschool Population

Homeschool children may rely solely on organized sports and physical activities to achieve recommended levels of physical activity and fitness. The purpose of this study was to investigate differences in fitness levels between homeschool children who did, and did not, participate in organized sports or physical activities, and then examine relationships between hours per week in sports or physical activities and cardiorespiratory fitness as measured by portions of the FitnessGram^® test battery. Organized sports/physical activity participation information was gathered on 100 children ages 10-17 years who completed tests of upper, abdominal, and cardiorespiratory fitness. The current investigation revealed that participation alone was not associated with higher levels of physical fitness as assessed by the 90° push-up test or curl-up test nor was time in participation related to cardiorespiratory fitness as assessed by the Progressive Aerobic Capacity Endurance Run (PACER). These activities alone may be insufficient for meeting physical activity recommendations and improving physical fitness. Therefore, children and adolescents educated at home may need additional opportunities to participate in unstructured daily physical activity.

Physical education and leisure-time sport reduce overweight and obesity: a number needed to treat analysis

BACKGROUND

School-based physical education (PE) and organised leisure-time sports participation (LTSP) represent important physical activity opportunities for children. We examined the preventive effect of increased PE as well as LTSP on overweight and obesity (OW/OB) in school children.

METHODS

Longitudinal data from children attending 10 primary schools in the Danish municipality of Svendborg, comprising 6 intensive PE (270 min/week) and 4 control (90 min/week) schools were assessed. Age- and sex-specific cut-offs for body mass index (BMI) determined OW/OB status. Associations between OW/OB status and school type (intensive PE or control) or LTSP were investigated using mixed, multilevel logistic regression models. Significant parameter estimates were converted into number needed to treat statistics (NNT).

RESULTS

In total, 1009 children (53.3% female; mean age 8.4 ± 1.4 years) were included in the analysis, with 892 children (52% female) being normal weight (NW) at baseline. Eighteen (NNT = 17.1; 95% CI [11.0, 226.1]) children attending an intensive PE school for 2 years, resulted in one fewer case of OW/OB compared with attendance at a normal PE school. For NW children, prevention of one case of OW/OB requires 36 (NNT = 35.8; 95% CI [25.1, 596.3]) children to participate in intensive PE for 2 years in comparison with normal PE. LTSP over 2 years may prevent OW/OB if 15 children participate in one LTSP session/week, 9 in two LTSP sessions/week and 8 in three LTSP sessions/week; for normal weight children, 25 children had to participate in one LTSP session/week, 16 in two LTSP sessions/week and 14 in three LTSP sessions/week.

CONCLUSION

We provide the first NNT estimates of school-based PE and LTSP to prevent the onset of OW/OB. PE, and separately, LTSP seem to have both a protective and a treatment effect against OW/OB in children.

Children's physical activity and sedentary time compared using assessments of accelerometry counts and muscle activity level

Background

This research compared accelerometry (ACC)-derived and muscle electromyography (EMG)-based estimates of physical activity (PA) and sedentary time in typical PA tasks and during the daily lives of children.

Methods

Data was included from two exploratory studies. In Study I, 6–7-year-old children (n = 11, 64% girls) were assessed for eight PA tasks (walking, stair negotiation, climbing, crawling, swinging, balancing, trampoline jumping and a game of tag). In Study II, 7–9-year-old children (n = 14, 38% girls) were assessed for six PA tasks (walking, sitting, static squat, single leg hops, jump for height and standing long jump), and daily PA during one day with and one day without structured exercise. Quadriceps and hamstring muscle activity and inactivity using EMG shorts and acceleration by waist-mounted accelerometer were simultaneously measured and classified as sedentary, light, moderate and vigorous activity. Data from ACC was further analyzed using five different published cut-off points and varying time windows (1−60 s) for comparison with EMG.

Results

In the PA tasks ACC counts and EMG amplitude showed marked differences in swinging, trampoline jumping, crawling, static squat, single leg hops, standing long jump and jump for height, the difference being over 170% when signals were normalized to that during walking. Furthermore, in walking, swinging, trampoline jumping, stair negotiation and crawling ACC classified over 60% of the time as vigorous-intensity activity, while EMG indicated primarily light- and moderate-intensity activities. During both days with and without exercise, ACC resulted in greater proportion of light activity (p < 0.01) and smaller proportion of moderate activity compared to EMG (p < 0.05). The choice of cut-off points and epoch length in ACC analysis influenced the classification of PA level and sedentary time. In the analysis of daily activities the cut-off points by Evenson et al. (2008) with epochs of 7.5 s and 15 s yielded the smallest difference (less than 10% of recording time at each intensity) against EMG-derived PA levels.

Discussion

This research provides novel insight on muscle activity and thereby on neuromuscular loading of major locomotor muscles during normal daily activities of children. While EMG and ACC provided similar estimates of sedentary time in 13 typical PA tasks, duration of light, moderate and vigorous PA varied considerably between the methods especially during walking, stair negotiation, crawling, swinging and trampoline jumping. Evenson et al.’s (2008) cut-off points with ≤15 s epoch provided similar classification of PA than EMG during daily life. Compared to impacts recorded using ACC, EMG can provide understanding on children’s neuromuscular loading during motor tasks that is useful when studying effects of PA interventions on, and development of, motor competence and coordination.