The association between childhood motor performance and developmental trajectories of sport participation over 5 years in Danish students aged 6-16-year-old.

Sports participation has potential to promote physical activity in youth. Unfortunately, sports participation and physical activity may decline from childhood to adolescence and into adulthood. Globally, only 20% of 13-15-year-olds meet the World Health Organisation recommendations for physical activity. This study aimed to investigate the 5-year trajectories of sports participation and their association with baseline motor performance in Danish school children as part of the Childhood Health Activity and Motor Performance School Study-Denmark (CHAMPS-DK), a school-based physical activity intervention study which investigated the health benefits of increased physical education lessons. Five distinct trajectories were identified, with group 1 maintained a stable trajectory of little to no sports participation, and group 2 showing a low decreasing trend. Group 3-5, the most sports active, demonstrated increasing sport participation at different rates. Baseline motor performance score was associated with the two most active sports participation groups. Students who were more physically active during school hours participated less in organised leisure time sports. This suggest focusing on improving motor performance in youth may support future sports participation and thus health-related physical activity. But also, that it might be necessary to engage and maintain children and adolescents in leisure time sports while implementing physical activity promotion interventions.

Physical Fitness Is Longitudinally Associated With Academic Performance During Childhood and Adolescence, and Waist Circumference Mediated the Relationship.

PURPOSE: The current investigation aimed to investigate the longitudinal association between physical fitness and academic performance over 3 years in adolescents. A secondary aim was to determine to what extent waist circumference mediated the association between physical fitness and academic performance. METHODS: For the current study, 1020 students from first grade [mean age: 7.87 (0.34) y] to fifth grade [mean age: 11.87 (0.37) y] were monitored annually for 3 years (2010-2013). Physical fitness was assessed using the Andersen test, 5 × 5-m shuttle run, jump height, and grip strength tests and by constructing a composite score combining all 4 fitness tests. Academic performance was assessed by national standardized tests in Danish language and math. Generalized structural equation modeling was used to evaluate the relationships between these variables. RESULTS: The Andersen test (standardized ß = 0.15 SD), shuttle run (ß = -0.18 SD), jump height (ß = 0.10 SD), and the fitness composite score (ß = 0.23 SD) were positively associated with academic performance over 3 years. In addition, waist circumference partially mediated the association between physical fitness and academic performance. CONCLUSION: Thus, physical fitness abilities should be stimulated during childhood and early adolescence because of their positive association with academic performance.

Musculoskeletal extremity pain in Danish school children - how often and for how long? The CHAMPS study-DK.

BACKGROUND: Musculoskeletal pain is common in childhood and adolescence, and may be long-lasting and recurrent. Musculoskeletal problems tend to follow adolescents into adulthood, and therefore it is important to design better prevention strategies and early effective treatment. To this end, we need in-depth knowledge about the epidemiology of musculoskeletal extremity problems in this age group, and therefore, the aim of this study was to determine the prevalence, frequency and course of musculoskeletal pain in the upper and lower extremities in a cohort of Danish school children aged 8-14 years at baseline. METHODS: This was a prospective 3-year school-based cohort study, with information about musculoskeletal pain collected in two ways. Parents answered weekly mobile phone text messages about the presence or absence of musculoskeletal pain in their children, and a clinical consultation was performed in a subset of the children. RESULTS: We found that approximately half the children had lower extremity pain every study year. This pain lasted on average for 8 weeks out of a study year, and the children had on average two and a half episodes per study year. Approximately one quarter of the children had upper extremity pain every study year that lasted on average 3 weeks during a study year, with one and a half episodes being the average. In general, there were more non-traumatic pain episodes compared with traumatic episodes in the lower extremities, whereas the opposite was true in the upper extremities. The most common anatomical pain sites were 'knee' and 'ankle/ft'. CONCLUSION: Lower extremity pain among children and adolescents is common, recurrent and most often of non-traumatic origin. Upper extremity pain is less common, with fewer and shorter episodes, and usually with a traumatic onset. Girls more frequently reported upper extremity pain, whereas there was no sex-related difference in the lower extremities. The most frequently reported locations were 'knee' and 'ankle/ft'.

Results From Denmark's 2016 Report Card on Physical Activity for Children and Youth.

BACKGROUND: The first Danish Report Card on Physical Activity (PA) for Children and Youth describes Denmark's efforts in promoting and facilitating PA and PA opportunities for children and youth. METHODS: The report card relies primarily on a synthesis of the best available research and policy strategies identified by the Report Card Research Committee consisting of a wide presentation of researchers and experts within PA health behaviors and policy development. The work was coordinated by Research and Innovation Centre for Human Movement and Learning situated at the University of Southern Denmark and the University College Lillebaelt. Nine PA indicators were graded using the Active Healthy Kids Canada Report Card development process. RESULTS: Grades from A (highest) to F (lowest) varied in Denmark as follows: 1) Overall Physical Activity (D+), 2) Organized Sport Participation (A), 3) Active Play (INC; incomplete), 4) Active Transportation (B), 5) Sedentary Behaviors (INC), 6) Family and Peers (INC), 7) School (B), 8) Community and the Built Environment (B+), and 9) Government strategies and investments (A-). CONCLUSIONS: A large proportion of children in Denmark do not meet the recommendations for PA despite the favorable investments and intensions from the government to create good facilities and promote PA.

The effect of a multi-component camp-based weight-loss program on children's motor skills and physical fitness: a randomized controlled trial.

BACKGROUND: Many weight-loss programs in children are performed without specific foci on training both physical fitness and motor skills. The aim of this study was to describe the effect of a one-year weight-loss program on children's motor skills and physical fitness. METHODS: Participants included 115 overweight fifth-grade children (12.0 years) randomized into either a Day-Camp Intervention Arm (DCIA), with a subsequent family-based support program or a low-intense Standard Intervention Arm (SIA). Physical fitness was assessed by vertical jump, hand grip strength, and a progressive cardio-respiratory fitness test. Motor skills were assessed by the Movement Assessment Battery for Children - second edition (M-ABC-2), age band 3. RESULTS: Loss to follow-up after 52 weeks was 19 % and 32 % in the DCIA and SIA, respectively. Balance skills were improved post-camp, but not after 52 weeks in children from the DCIA compared to the SIA. Contrary to the expected, children from the SIA improved aiming and catching skills relative to the DCIA children. Overall z-scores of the physical fitness components and cardio-respiratory fitness improved more in children from the DCIA compared to children from the SIA. CONCLUSION: In conclusion, the day-camp intervention led to improvements in physical fitness but not in motor skills compared to the standard intervention. Including both motor skills and physical fitness could advantageously be considered in future immersive intervention programmes. TRIAL REGISTRATION: Clinicaltrials NCT01574352, March 26, 2012 (retrospectively registered).

Motor Performance as Risk Factor for Lower Extremity Injuries in Children.

PURPOSE: Physical activity-related injuries in children constitute a costly public health matter. The influence of motor performance on injury risk is unclear. The purpose of this study was to examine if motor performance was a risk factor of traumatic and overuse lower extremity injuries in a normal population of children. METHODS: This study included 1244 participants from 8 to 14 yr old at baseline, all participating in the "Childhood Health, Activity and Motor Performance School Study Denmark." The follow-up period was up to 15 months. The motor performance tests were static balance, single leg hop for distance, core stability tests, vertical jump, shuttle run, and cardiorespiratory fitness test. Lower extremity injuries were registered by clinicians using weekly questionnaires and classified according to the International Classification of Diseases, 10th Revision, system. RESULTS: Poor balance increased the risk for traumatic injury in the foot region (incidence rate ratio [IRR] = 1.09-1.15), and good performance in single leg hop for distance protected against traumatic knee injuries (IRR = 0.66-0.68). Good performance in core stability tests and vertical jump increased the risk for traumatic injuries in the foot region (IRR = 1.12-1.16). Poor balance increased the risk for overuse injuries in the foot region (IRR = 1.65), as did good performance in core stability tests and shuttle run, especially for knee injuries (IRR = 1.07-1.18). CONCLUSIONS: Poor balance (sway) performance was a consistent predictor of traumatic injuries, in particular, for traumatic ankle injuries. Good motor performance (core stability, vertical jump, and shuttle run) was positively associated with traumatic and overuse injuries and negatively (single leg hop) associated with traumatic injuries, indicating different influences on injury risk. Previous injury was a confounder affecting the effect size and the significance. More studies are needed to consolidate the findings, to clarify the influence of different performance tests on different types of injuries, and to examine the influence of behavior in relation to injury risk.

The extent and risk of knee injuries in children aged 9-14 with Generalised Joint Hypermobility and knee joint hypermobility - the CHAMPS-study Denmark.

BACKGROUND: Generalised Joint Hypermobility (GJH) is suggested as an aetiological factor for knee injuries in adolescents and adults. It is presumed that GJH causes decreased joint stability, thereby increasing the risk of knee injuries during challenging situations like jumping and landing. The aim was to study the extent and risk of knee injuries in children with GJH and knee hypermobility. METHODS: In total, 999 children (9-14 years) were tested twice during spring 2012 and 2013 with Beighton's Tests (BT) for hypermobility, a 0-9 scoring system. GJH was classified with cut-point ≥5/9 on both test rounds. On basis of weekly cell phone surveys of knee pain, children requiring clinical examination were seen. Traumatic and overuse knee injuries were registered by WHO ICD-10 diagnoses. Logistic regression and Poisson regression models with robust standard errors were used to examine the association between GJH and knee injuries, taking into account clustering on school class levels. RESULTS: Totally, 36 children were classified GJH on both test rounds. Overuse knee injuries were the most frequent injury type (86 %), mainly apophysitis for both groups (61 %), other than patella-femoral pain syndrome for the control group (13 %). For traumatic knee injuries, distortions and contusions were most frequent in both groups (51 % resp. 36 %), besides traumatic lesions of knee tendons and muscles for the control group (5 %). No significant association was found between overuse knee injuries and GJH with/without knee hypermobility (OR 0.69, p = 0.407 resp. OR 0.75, p = 0.576) or traumatic knee injuries and GJH with/without knee hypermobility (OR 1.56, p = 0.495 resp. OR 2.22, p = 0.231). CONCLUSIONS: Apophysitis, distortions and contusions were the most frequent knee injuries. Despite the relatively large study, the number of children with GJH and knee injuries was low, with no significant increased risk for knee injuries for this group. This questions whether GJH is a clinically relevant risk factor for knee injuries in school children aged 9-14 years. A fluctuation in the individual child's status of GJH between test rounds was observed, suggesting that inter- and intra-tester reproducibility of BT as well as growth may be considered important confounders to future studies of children with GJH.

Motor Performance as Predictor of Physical Activity in Children: The CHAMPS Study-DK.

PURPOSE: Physical activity (PA) is associated with several health benefits in children, and PA habits developed in childhood tend to persist into adulthood. PA may be the foundation of a healthy lifestyle, and motor performance has been shown to be positively associated with PA in cross-sectional studies. The purpose of this study was to explore the longitudinal relation between motor performance and PA in a 3-yr follow-up study. METHODS: Longitudinal analyses were performed using data from 673 participants (44% boys, 6-12 yr old) who had been included in the Childhood Health Activity and Motor Performance School study-DK. Baseline motor performance tests consisted of vertical jump, shuttle run, hand grip strength, backward balance, precision throw, and cardiovascular fitness. Composite z-scores were generated to express health-related fitness and performance-related fitness. PA was measured by accelerometer at baseline and at 3-yr follow-up and was expressed as a percentage of time in moderate-to-vigorous PA. RESULTS: Cardiovascular fitness, vertical jump, health-related fitness, and performance-related fitness showed significant positive associations with 3-yr follow-up measures of PA in both sexes. Furthermore, shuttle run showed significant inverse associations with follow-up measures of PA for both sexes. CONCLUSIONS: Cardiorespiratory fitness, shuttle run, vertical jump, health-related fitness, and performance-related fitness were significantly associated with time spent in moderate-to-vigorous PA at 3-yr follow-up. The clinical relevance of the results indicates that cardiorespiratory fitness and shuttle run in childhood may be important determinants of PA in adolescence.

Field assessment of balance in 10 to 14 year old children, reproducibility and validity of the Nintendo Wii board.

BACKGROUND: Because body proportions in childhood are different to those in adulthood, children have a relatively higher centre of mass location. This biomechanical difference and the fact that children's movements have not yet fully matured result in different sway performances in children and adults. When assessing static balance, it is essential to use objective, sensitive tools, and these types of measurement have previously been performed in laboratory settings. However, the emergence of technologies like the Nintendo Wii Board (NWB) might allow balance assessment in field settings. As the NWB has only been validated and tested for reproducibility in adults, the purpose of this study was to examine reproducibility and validity of the NWB in a field setting, in a population of children. METHODS: Fifty-four 10-14 year-olds from the CHAMPS-Study DK performed four different balance tests: bilateral stance with eyes open (1), unilateral stance on dominant (2) and non-dominant leg (3) with eyes open, and bilateral stance with eyes closed (4). Three rounds of the four tests were completed with the NWB and with a force platform (AMTI). To assess reproducibility, an intra-day test-retest design was applied with a two-hour break between sessions. RESULTS: Bland-Altman plots supplemented by Minimum Detectable Change (MDC) and concordance correlation coefficient (CCC) demonstrated satisfactory reproducibility for the NWB and the AMTI (MDC: 26.3-28.2%, CCC: 0.76-0.86) using Centre Of Pressure path Length as measurement parameter. Bland-Altman plots demonstrated satisfactory concurrent validity between the NWB and the AMTI, supplemented by satisfactory CCC in all tests (CCC: 0.74-0.87). The ranges of the limits of agreement in the validity study were comparable to the limits of agreement of the reproducibility study. CONCLUSION: Both NWB and AMTI have satisfactory reproducibility for testing static balance in a population of children. Concurrent validity of NWB compared with AMTI was satisfactory. Furthermore, the results from the concurrent validity study were comparable to the reproducibility results of the NWB and the AMTI. Thus, NWB has the potential to replace the AMTI in field settings in studies including children. Future studies are needed to examine intra-subject variability and to test the predictive validity of NWB.