Boys demonstrate greater knee frontal moments than girls during the impact phase of cutting maneuvers, despite age-related increases in girls.

PURPOSE: Anterior cruciate ligament (ACL) injury rate is low among children, but increases during adolescence, especially in girls. Increases in the knee valgus moment within 70 ms of contact with the ground (KFM0-70) may explain the sex-specific increase in the risk of ACL injury. The purpose of the study was to investigate sex-dependent changes in the KFM0-70 from pre-adolescence to adolescence during a cutting maneuver (CM). METHODS: Kinematic and kinetic data during the CM task, performed before and after physical exertion, were recorded using a motion capture system and a force plate. A total of 293 team handball and soccer players, aged 9-12 years, were recruited. A number of those who continued sports participation (n = 103) returned five years later to repeat the test procedure. Three mixed-model analysis of variance (ANOVA) for repeated measures tests were used to determine the effects of sex and age period on the KFM0-70 (1: with no adjustment, 2: adjusted for repeated measurements, and 3: additionally adjusted with hip and knee joint frontal plane kinematics). RESULTS: Boys had significantly higher KFM0-70 than girls at both age periods (p < 0.01 for all models). Girls, not boys, demonstrated significantly increased KFM0-70 from pre-adolescence to adolescence. Importantly, this was fully explained by kinematic variables. CONCLUSION: Although the marked increase in KFM0-70 seen in girls may play a role in their risk of ACL rupture, the higher values demonstrated by boys during CM reflect the complexity of multifactorial biomechanical risk factor analysis. The role of kinematics in mediating the KFM0-70 provides means for modification of this risk factor, but as boys had higher joint moments, continued investigation into sex-dependent biomechanical risk factors is warranted. LEVEL OF EVIDENCE: II.

[Physique of children and adolescents in Northern Iceland then and now].

INTRODUCTION: In the first half of the 20th century, Icelandic doctors and teachers began documenting the health of school children, believing that physical measurements were important to monitoring physical development. The measurements could also be used for comparison in other areas and for reasearch. At the Reginonal Archives of Skagafjordur, rare data about the physique of children in Saudarkrokur in 1912-1953, measured by Jon Th. Bjornsson, is preserved. MATERIAL AND METHODS: Height, weight, grip strenght, thorax expansion and tidal volume were measured twice in 2018-2019 on 7-15-year-old children in elementary schools in Saudarkrokur and Varmahlid. These measurements were compared with similar measurements from 1912-1953. RESULTS: Children in 2018-2019 at ages 7-15 years were significantly taller, heavier, with greater thorax expansion and tidal volume than their peers in 1912-1953 (p<0,001-0,037). Children in 2018-2019 at ages 7-14 years had significantly higher body mass index than their peers in 1912-1953 (p<0,001-0,027). If adjusted for height and weight in thorax expansion and tidal volume measurements, similar results were found. Children in 2018-2019 had significantly less grip strength than their peers in 1912-1953 at ages 7 and 9-12-years when adjusted for height and weight (p<0,001-0,025). There was significant development in the physique of children over the years 1912-1953 in most measurements and age groups (p<0,001-0,040). CONCLUSIONS: A significant increase in measured factors in 2018-2019 compared to 1912-1953 can possibly be attributed to improved quality of life.

Predictive variables for poor long-term physical recovery after intensive care unit stay: An exploratory study.

BACKGROUND: Elucidating factors that influence physical recovery of survivors after an intensive care unit (ICU) stay is paramount in maximizing long-term functional outcomes. We examined potential predictors for poor long-term physical recovery in ICU survivors. METHODS: Based on secondary analysis of a trial of 50 ICU patients who underwent mobilization in the ICU and were followed for one year, linear regression analysis examined the associations of exposure variables (baseline characteristics, severity of illness variables, ICU-related variables, and lengths of ICU and hospital stay), with physical recovery variables (muscle strength, exercise capacity, and self-reported physical function), measured one year after ICU discharge. RESULTS: When the data were adjusted for age, female gender was associated with reduced muscle strength (P = .003), exercise capacity (P < .0001), and self-reported physical function (P = .01). Older age, when adjusted for gender, was associated with reduced exercise capacity (P < .001). After adjusting for gender and age, an association was observed between a lower score on one or two physical recovery variables and exposure variables, specifically, high body mass index, low functional independence, comorbidity and low self-reported physical function at baseline, muscle weakness at ICU discharge, and longer hospital stay. No adjustment was made for cumulative type I error rate due to small number of participants. CONCLUSION: Elucidating risk factors for poor long-term physical recovery after ICU stay, including gender, may be critical if mobilization and exercise are to be prescribed expediently during and after ICU stay, to ensure maximal long-term recovery.

Factors predicting identity as educators and openness to improve: an exploratory study.

CONTEXT: Researchers suggest that teachers' work environment affects their sense of connectedness and appreciation, which affects their educator identity. However, sessional (also known as adjunct, clinical, contingent and non-tenured) faculty members may struggle with their educator identity. The purpose of this exploratory study was to examine the extent to which perceived connectedness and received appreciation predicted identity as a medical (health care science) educator and openness to improve in tenure-track and sessional faculty members. METHODS: We utilised an 'identification with teaching' scale to measure medical educator identity. We developed scales to measure perceived connectedness to university department, openness to improve teaching, and appreciation as a motivation to try a new teaching method. We then hypothesised a path model between these constructs. We surveyed faculty members at a health sciences school and performed confirmatory factor analyses and structural equation modelling using data from a sample of 73 tenure-track and 146 sessional faculty members to explore support for the hypothesised model. RESULTS: Connectedness and appreciation predicted identity as a medical educator and openness to improve in different ways for sessional and tenure-track faculty members. For tenure-track faculty members, appreciation predicted medical educator identity and openness to improve, whereas a sense of connectedness trended towards predicting an openness to improve. For sessional faculty members, connectedness to their department predicted their identity as a medical educator, which acted as a mediator to predict an openness to improve. DISCUSSION: Our data supported the hypothesised model, but the sessional and tenure-track faculty models differed in strength and focus. We explore reasons for these differences based on the working environment of each teacher type. We suggest that the two models partially explain the transformation from 'a clinician who teaches' to a medical educator. Finally, we make suggestions for how identity as a medical educator and openness to improve may be encouraged in both types of teachers.

Above average increases in body fat from 9 to 15 years of age had a negative impact on academic performance, independent of physical activity.

AIM: The associations between body fat levels and physical activity with academic performance are inconclusive and were explored using longitudinal data. METHODS: We enrolled 134/242 adolescents aged 15, who were studied at the age of nine and agreed to be followed up from April to May 2015 for the Health behaviours of Icelandic youth study. Accelerometers measured physical activity, body mass indexes (BMI) were calculated and dual-energy X-ray absorptiometry scans assessed the participants' body composition at nine and 15. Their language and maths skills were compared to a growth model that estimated the academic performances of children born in 1999. RESULTS: Higher than normal body fat levels between the ages of nine and 15 were negatively associated with maths performance, but the same association was not found for Icelandic language studies. These were Pearson's r = -0.24 (p = 0.01) for BMI and Pearson's r = -0.34 (p = 0.01) for the percentage of body fat. No associations were found with changes in physical activity. CONCLUSION: Children who put on more body fat than normal between the ages of nine and 15 had an increased risk of adverse academic performance that was independent of changes in physical activity.

Injury Pattern in Icelandic Elite Male Handball Players.

OBJECTIVE: To examine the incidence, type, location, and severity of injuries in Icelandic elite male handball players and compare across factors like physical characteristics and playing position. DESIGN: Prospective cohort study. SETTING: The latter part of the preseason and the competitive season of Icelandic male handball. PARTICIPANTS: Eleven handball teams (185 players) from the 2 highest divisions in Iceland participated in the study. Six teams (109 players) completed the study. VARIABLES MEASURED: Injuries were recorded by the players under supervision from their team physiotherapists or coaches. Coaches recorded training exposure, and match exposure was obtained from the Icelandic and European Handball Federations. The players directly recorded potential risk factors, such as age, height, weight, previous injuries, and player position. MAIN OUTCOME MEASURES: Injury incidence and injury location and number of injury days. RESULTS: Recorded time-loss injuries were 86, of which 53 (62%) were acute and 33 (38%) were due to overuse. The incidence of acute injuries was 15.0 injuries/1000 hours during games and 1.1 injuries/1000 hours during training sessions. No significant difference was found in injury incidence between teams, but number of injury days did differ between teams (P = 0.0006). Acute injuries were most common in knees (26%), ankles (19%), and feet/toes (17%), but overuse injuries occurred in low back/pelvic region (39%), shoulders (21%), and knees (21%). Previous knee injuries were the only potential risk factor found for knee injury. CONCLUSIONS: The results indicate a higher rate of overuse injuries in low back/pelvic region and shoulders than in comparable studies.

Dynamic sitting: Measurement and associations with metabolic health.

Dynamic sitting, such as fidgeting and desk work, might be associated with health, but remains difficult to identify out of accelerometry data. We examined, in a laboratory study, whether dynamic sitting can be identified out of triaxial activity counts. Among 18 participants (56% men, 27.3 ± 6.5 years), up to 236 counts per minute were recorded in the anteroposterior and mediolateral axes during dynamic sitting using a hip-worn accelerometer. Subsequently, we examined in 621 participants (38% men, 80.0 ± 4.7 years) from the AGES-Reykjavik Study whether dynamic sitting was associated with cardio-metabolic health. Compared to participants who recorded the fewest dynamic sitting minutes (Q1), those with more dynamic sitting minutes had a lower BMI (Q2 = -1.39 (95%CI = -2.33;-0.46); Q3 = -1.87 (-2.82;-0.92); Q4 = -3.38 (-4.32;-2.45)), a smaller waist circumference (Q2 = -2.95 (-5.44;-0.46); Q3 = -3.47 (-6.01;-0.93); Q4 = -8.21 (-10.72;-5.71)), and a lower odds for the metabolic syndrome (Q2 = 0.74 [0.45;1.20] Q3 = 0.58 [0.36;0.95]; Q4 = 0.36 [0.22;0.59]). Our findings suggest that dynamic sitting might be identified using accelerometry and that this behaviour was associated with health. This might be important given the large amounts of time people spend sitting. Future studies with a focus on validation, causation and physiological pathways are needed to further examine the possible relevance of dynamic sitting.

Needs, motivations, and identification with teaching: a comparative study of temporary part-time and tenure-track health science faculty in Iceland.

BACKGROUND: About 70% of teachers who instruct healthcare students are considered sessional (adjunct/temporary part-time) faculty and receive limited instruction in pedagogy. Sessional faculty may feel isolated and struggle with their teacher identity, and are often assumed to vary in their commitment, motivation, and ability to teach. However, research on teaching identity, motivations, and needs of sessional faculty is lacking. The aim of this study was to compare similarities and differences between sessional and tenure-track faculty across a health science school to guide faculty development for sessional faculty. METHODS: We developed an online needs assessment survey, based on informal interviews and literature reviews. Seventy-eight tenure-track faculty and 160 sessional faculty completed the survey (37, 25% response rate, respectively). We used validated scales to assess intrinsic motivation, identified regulated motivation, and identification with teaching, as well as developed scales (perceived connectedness, motivated by appreciation to try new teaching method) and single items. All scales demonstrated good internal consistency. We compared sessional and tenure-track faculty using t-tests/chi-square values. RESULTS: We found similarities between sessional and tenure-track faculty in intrinsic motivation, identified regulated motivation, and identification with teaching. However, sessional faculty perceived less department connectedness and were more motivated to improve instruction if shown appreciation for trying new teaching methods. Sessional faculty agreed more that they desired pedagogy instruction before starting to teach and that teachers should invest energy in improving their teaching. Admitting to less participation in activities to enhance teaching in the last year, sessional faculty were more interested in digital formats of faculty development. CONCLUSION: Our comparison suggested that sessional faculty value being a teacher as part of their self, similar to tenured faculty, but desired more appreciation for efforts to improve and perceived less connectedness to their university department than tenured faculty. They also preferred digital formats for pedagogy to improve accessibility, prior to and throughout their teaching career to support their development as teachers. Using this information as a guide, we provide suggestions for faculty development for sessional faculty. Supporting sessional faculty in the health sciences should improve the quality of teaching and positively affect student learning.

Timing, not magnitude, of force may explain sex-dependent risk of ACL injury.

PURPOSE: The anterior cruciate ligament is loaded through valgus moment, vertical ground reaction force, and internal rotation moment. The aim of this study was to compare the timing of force peaks during early stance between youth girls and boys. METHODS: One-hundred and twenty-nine team sport athletes aged 9-12 completed a total of 2540 cutting maneuvers captured with an 8-camera motion capture system. Timing of early force peaks was analyzed within 100 ms after ground contact. RESULTS: Genders showed different mean (95% CI) time to peak valgus-(32 ms (30-33 ms) vs 37 ms (36-38 ms), P < 0.001) and time to peak internal rotation moments (36 ms (35-37 ms) vs 38 ms (37-39 ms), P = 0.029) but not time to peak vertical ground reaction force [38 ms (37-40 ms) vs 37 ms (36-38 ms, n.s.)]. Girls showed a smaller time between vertical ground reaction force and valgus moment peaks (mean (95% CI) of 1 ms (1-2 ms) vs 7 ms (5-9 ms), P < 0.001), and valgus- and internal rotation moment peaks (0 ms (- 2 to 1.0 ms) vs - 5 ms (- 6 to - 3 ms), P = 0.0003) but not between internal rotation moment and vertical ground reaction force. CONCLUSIONS: Concurrent force peaks are more common for girls compared with boys, leading to more frequent multi-planar loading of the knee. Timing may explain sex-dependent risk of ACL injuries. Exposure to repeated cutting movements may result in greater ACL injury risk due to timing of knee forces as well as magnitude. Such exposure should be minimized for at-risk athletes. LEVEL OF EVIDENCE: III.

Organized leisure-time sport participation and academic achievement in preadolescents.

AIMS: The aims of this study were to study the correlation between lifestyle-related factors, such as organized leisure-time sport participation (OLSP), cardiorespiratory fitness, and adiposity, and academic achievement among preadolescents. METHODS: A cross-sectional study involving 248 nine-year-old school children was carried out. OLSP was self-reported with parental assistance, categorized as ≤ 1× a week, 2-3× a week, and ≥ 4× times a week or more. Academic achievement was estimated with results from standardized test scores in Icelandic and math. Cardiorespiratory fitness was estimated using a maximal cycle ergometer test. The sum of four skinfolds was used to estimate adiposity. RESULTS: Tests of between-subjects effect indicated that OLSP significantly correlated with achievement in math only (F(2,235) = 3.81, p = 0.024). Further analysis showed that the two less active groups had significantly lower scores in math compared to the most active group with OLSP ≥ 4× times a week or more (2-3× times a week, unstandardized coefficient (b) = -4.08, 95% confidence interval (CI) [-7.09, -1.07]; ≤ 1× a week, b = -3.84, 95% CI [-7.59, -0.08]), independent of sex, age, maturity level (age to/from peak height velocity), family structure, and parental education. Neither cardiorespiratory fitness nor adiposity significantly correlated with academic achievements. CONCLUSIONS: The study's result indicates that frequent (four times per week or more often) sport participation is not harmful but may be beneficial to learning. However, further intervention-based study of this topic is needed to determine if this relationship is causal.

The association of cardiorespiratory fitness to health independent of adiposity depends upon its expression.

BACKGROUND: The strong relation between cardiorespiratory fitness (CRF) and adiposity renders their independent associations to metabolic risk factors difficult to ascertain. AIM: To determine the associations of CRF and CRF relative to fat-free mass (CRFFFM) to total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin and homeostasis model assessment (HOMA) and distinguish these relations from the association to adiposity. SUBJECTS AND METHODS: Anthropometrics, body fat percentage (%Fat) and fat-free mass (from dual energy X-ray absorptiometry) were measured in 127 (66 females) 17 and 23 year-olds. CRF from a maximal workload on a graded bicycle test and fasting blood samples were obtained. RESULTS: CRF was significantly related to total cholesterol, triglycerides, insulin and HOMA (r = -0.24 to -0.49, p < 0.03), as were all adiposity measures (r = 0.21-0.53, p < 0.05). Correcting CRF for %Fat rendered the relation to metabolic risk factors non-significant (p = 0.09-0.21); however, CRFFFM was significantly related to the metabolic risk factors (r = -0.25 to -0.32, p < 0.02). CONCLUSIONS: CRFFFM, where adiposity has been removed, is associated with metabolic risk factors, whereas CRF, which is related to adiposity, is not after adjustment for fatness. Previously, independent effects of CRF on health may have been underestimated by using an expression of CRF strongly related to the adiposity measures.

Common variants on chromosomes 2q35 and 16q12 confer susceptibility to estrogen receptor-positive breast cancer.

Familial clustering studies indicate that breast cancer risk has a substantial genetic component. To identify new breast cancer risk variants, we genotyped approximately 300,000 SNPs in 1,600 Icelandic individuals with breast cancer and 11,563 controls using the Illumina Hap300 platform. We then tested selected SNPs in five replication sample sets. Overall, we studied 4,554 affected individuals and 17,577 controls. Two SNPs consistently associated with breast cancer: approximately 25% of individuals of European descent are homozygous for allele A of rs13387042 on chromosome 2q35 and have an estimated 1.44-fold greater risk than noncarriers, and for allele T of rs3803662 on 16q12, about 7% are homozygous and have a 1.64-fold greater risk. Risk from both alleles was confined to estrogen receptor-positive tumors. At present, no genes have been identified in the linkage disequilibrium block containing rs13387042. rs3803662 is near the 5' end of TNRC9 , a high mobility group chromatin-associated protein whose expression is implicated in breast cancer metastasis to bone.

Importance of physical health and health-behaviors in adolescence for risk of dropout from secondary education in young adulthood: an 8-year prospective study.

BACKGROUND: Education and health constitute two interlinked assets that are highly important to individuals. In Iceland, prevalence of dropout from secondary education poses a considerable problem. This 8-year prospective study assesses to what extent poor physical health and negative health-behaviors of Icelandic adolescents predict increased odds of dropout from secondary education. METHODS: The sample included n = 201 Icelandic children who participated at age 15 (baseline) and again at age 23 (follow-up). Data included objective measurements of physical health and questionnaires assessing health-behaviors, education status, parental education, neighborhood characteristics, self-esteem, and depression. Independent t-tests and chi-square were used to assess differences in physical health and health-behaviors at follow-up stratified by education status. Ordinal regression models were conducted to assess whether physical health and health-behaviors at age 15 predicted increased odds of dropout from secondary education at age 23, independent of gender, parental education and psychological factors. RESULTS: At age 23, 78 % of girls and 71 % of boys had completed a secondary education. Completion of a secondary education was associated with significant health benefits, especially among women. Women without a secondary education had lower fitness, more somatic complaints, higher diastolic blood pressure, less sports participation, and poorer sleep, whilst men without a secondary education watched more television. In logistic regression models somatic complaints during adolescence were associated with 1.09 (95 % CI: 1.02-1.18) higher odds of dropout from secondary education in young adulthood, independent of covariates. Health-behaviors associated with higher dropout odds included smoking (3.67, 95 % CI: 1.50-9.00), alcohol drinking (2.57, 95 % CI: 1.15-5.75), and time spent watching television (1.27, 95 % CI:1.03-1.56), which were independent of most covariates. Finally, mother's higher education was strongly associated with significantly lower dropout odds (OR 0.54, 95 % CI: 0.34-0.88) independent of father's education and psychological factors, whilst high self-esteem was independently associated with lower dropout odds (OR 0.91, 95 % CI: 0.85-0.98). CONCLUSIONS: Completion of a secondary education yields substantial physical health benefits for young women, but not for men. Importantly, somatic complaints and negative health-behaviors among adolescent boys and girls adversely impact their educational outcomes later in life, and may have widespread consequences for their future prospects.

Gender differences in development of mental well-being from adolescence to young adulthood: an eight-year follow-up study.

BACKGROUND: The transition from adolescence to young adulthood is marked by many changes. Mental well-being plays an important role in how individuals deal with these changes and how they develop their lifestyle. The goal of this study was to examine gender differences in the long-term development of self-esteem and other mental well-being variables from the age of 15 to the age of 23. METHODS: A baseline measurement was performed in a nationwide sample of 385 Icelandic adolescents aged 15, and a follow-up measurement was conducted eight years later, when participants had reached the age of 23. Standardized questionnaires were used to measure self-reports of self-esteem, life satisfaction, body image, anxiety, depression and somatic complaints. RESULTS: Women improved their self-esteem significantly more than men from the age of 15 to 23 (p=0.004). Women were more satisfied with their life than men at the age of 23 (p=0.009). Men had a better body image, less anxiety, less depression and fewer somatic complaints than women, independent of age. Across gender, anxiety declined and somatic complaints became fewer (p<0.05). CONCLUSIONS These findings suggest that gender differences in mental well-being factors, favouring men, found in adolescents, are not as long-lasting as previously thought. Women improve their mental well-being from adolescence to young adulthood while men's mental well-being does not change.

Objective measurements of daily physical activity patterns and sedentary behaviour in older adults: Age, Gene/Environment Susceptibility-Reykjavik Study.

BACKGROUND: objectively measured population physical activity (PA) data from older persons is lacking. The aim of this study was to describe free-living PA patterns and sedentary behaviours in Icelandic older men and women using accelerometer. METHODS: from April 2009 to June 2010, 579 AGESII-study participants aged 73-98 years wore an accelerometer (Actigraph GT3X) at the right hip for one complete week in the free-living settings. RESULTS: in all subjects, sedentary time was the largest component of the total wear time, 75%, followed by low-light PA, 21%. Moderate-vigorous PA (MVPA) was <1%. Men had slightly higher average total PA (counts × day(-1)) than women. The women spent more time in low-light PA but less time in sedentary PA and MVPA compared with men (P < 0.001). In persons <75 years of age, 60% of men and 34% of women had at least one bout ≥10 min of MVPA, which decreased with age, with only 25% of men and 9% of women 85 years and older reaching this. CONCLUSION: sedentary time is high in this Icelandic cohort, which has high life-expectancy and is living north of 60° northern latitude.

Limited effects of a 2-year school-based physical activity intervention on body composition and cardiorespiratory fitness in 7-year-old children.

The aim of this study was to assess the effects of a 2-year cluster-randomized physical activity and dietary intervention program among 7-year-old (at baseline) elementary school participants on body composition and objectively measured cardiorespiratory fitness. Three pairs of schools were selected and matched, then randomly selected as either an intervention (n = 151) or control school (n = 170). None of the effect sizes of body composition were statistically significant. Children in the intervention group increased their fitness by an average of 0.37 z score units more than the controls (95% CI:-0.27 to 1.01, P = 0.18), representing an improvement of 0.286 W/kg. Boys had higher fitness (mean(diff) = 0.35 z scores, 95% CI: 0.13-0.58, P = 0.001) than girls, independent of study group, fitness z score at baseline and body mass index. Post hoc analysis showed that the intervention school with the highest fitness z score change was significantly different from two of the lowest control schools (mean(diff) = 0.83 z scores, 95% CI: 0.44-1.21, P < 0.0001 and mean(diff) = 0.70 z scores, 95% CI: 0.29-1.10, P = 0.01), but it was also significantly different from the lowest intervention school (mean(diff) = 0.59 z scores, 95% CI: 0.19-0.99, P = 0.05). The results of this intervention are inconclusive as regards to the effects on fitness, but the intervention did not have any statistically significant effect on body composition.

Assessment of a two-year school-based physical activity intervention among 7-9-year-old children.

BACKGROUND: Physical activity (PA) in children has declined in recent decades, highlighting the need for effective intervention programs for school-aged children. The main objective of this study was to assess to what extent PA during and after school hours changed among children who received a progressive two-year long intervention vs. that of children who only received general curriculum-based PA. METHODS: A cluster randomized intervention study was conducted and six elementary schools randomly assigned to serve as control- or intervention schools. All children attending second grade (mean age = 7.4 years - born in 1999) were invited to participate in the fall of 2006 (N = 320, 82% participated), again in 2007 (midpoint) and 2008 (end of intervention). The intervention consisted of multi-component PA-intervention during school hours and was conducted by teachers at each intervention school. PA was assessed by means of accelerometers and subjectively at the intervention schools via teachers' PA log-books. RESULTS: There was no difference in PA intensity (minutes of moderate-to-vigorous physical activity - min of MVPA) between the two study groups at baseline, but children in the intervention schools were more physically active at moderate-to-vigorous intensity compared to those in control schools after one year of intervention (mean difference of MVPAlog-minutes: 0.61, 95%CI: 0.02, 1.20, p = 0.04). Moreover, the model for minutes of MVPA during school hours, showed a significant three-way interaction between time at mid-point, group and gender (mean difference of MVPAlog-minutes: 1.06, 95%CI: 0.15, 1.97, p = .02), indicating a significantly greater increase among the boys in the intervention schools compared to girls. No difference in PA was detected between the study groups at the end of the study period after two years of intervention. CONCLUSIONS: The results suggest that the objective of increasing PA at school was met after one year of intervention, and it was more pronounced among boys. The lack of increase at the end of the study period suggested that any increase in PA during school may highly depend on both motivation and training of general teachers. Boys may respond better to PA interventions such as the one described in this study.

Effects of kinesio tape compared with nonelastic sports tape and the untaped ankle during a sudden inversion perturbation in male athletes.

STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To examine the effect of 2 adhesive tape conditions compared to a no-tape condition on muscle activity of the fibularis longus during a sudden inversion perturbation in male athletes (soccer, team handball, basketball). BACKGROUND: Ankle sprains are common in sports, and the fibularis muscles play a role in providing functional stability of the ankle. Prophylactic ankle taping with nonelastic sports tape has been used to restrict ankle inversion. Kinesio Tape, an elastic sports tape, has not been studied for that purpose. METHODS: Fifty-one male premier-league athletes were tested for functional stability of both ankles with the Star Excursion Balance Test. Based on the results, those with the 15 highest and those with the 15 lowest stability scores were selected for further testing. Muscle activity of the fibularis longus was recorded with surface electromyography during a sudden inversion perturbation. Each participant was tested under 3 conditions: ankle taped with nonelastic white sports tape, ankle taped with Kinesio Tape, and no ankle taping. Differences in mean muscle activity were evaluated with a 3-way mixed-model analysis of variance (ANOVA) for the 3 conditions, across four 500-millisecond time frames, and between the 2 groups of stable versus unstable participants. Differences in peak muscle activity and in the time to peak muscle activity were evaluated with a 2-way mixed-model ANOVA. RESULTS: Significantly greater mean muscle activity was found when ankles were taped with nonelastic tape compared to no tape, while Kinesio Tape had no significant effect on mean or maximum muscle activity compared to the no-tape condition. Neither stability level nor taping condition had a significant effect on the amount of time from perturbation to maximum activity of the fibularis longus muscle. CONCLUSION: Nonelastic sports tape may enhance dynamic muscle support of the ankle. The efficacy of Kinesio Tape in preventing ankle sprains via the same mechanism is unlikely, as it had no effect on muscle activation of the fibularis longus.

Effect of Sex on Anterior Cruciate Ligament Injury-Related Biomechanics During the Cutting Maneuver in Preadolescent Athletes.

BACKGROUND: There are 2 movement patterns associated with an anterior cruciate ligament (ACL) injury: dynamic valgus and stiff landing. Although sex-dependent differences have been identified for adults, less is known for preadolescent athletes regarding movement patterns known to load the ACL. HYPOTHESIS: We hypothesized that girls would demonstrate greater vertical ground reaction forces and knee valgus angles. We further hypothesized that the exercise intervention would affect girls more than boys and that this would primarily be demonstrated in less sagittal plane excursions, increased vertical ground reaction forces and knee valgus moments for girls than for boys. STUDY DESIGN: Controlled laboratory study. METHODS: Male and female soccer and handball players (n = 288; age range, 9-12 years) were recruited. A motion capture system synchronized to a force platform was used to record 5 trials of a cutting maneuver before and after a 5-minute fatigue intervention. Linear mixed models were constructed, and analysis of variance was used to analyze differences in outcomes associated with the sex of the athletes. RESULTS: Boys showed greater peak knee valgus moment (0.26 vs 0.22 N·m/kg, respectively; P = .048), peak knee internal rotation moment (-0.13 vs -0.10 N·m/kg, respectively; P = .021), knee rotation excursion (-7.9° vs -6.9°, respectively; P = .014), and knee extension excursion (2.7° vs 1.4°, respectively; P < .001) compared with that in girls. A significant sex × fatigue intervention interaction (F = 7.6; P = .006) was found, which was caused by a greater increase in first peak vertical ground-reaction force (vGRF) from before to after the fatigue intervention for girls (15.3 to 16.0 N/kg) compared with boys (16.4 to 16.5 N/kg). CONCLUSION: Differences detected for biomechanical factors during the cutting maneuver do not point to a greater ACL injury risk for prepubescent or early pubescent girls than for boys. Nonetheless, girls go on to develop more detrimental movement patterns in adolescence than those in boys in terms of biomechanical risk factors. CLINICAL RELEVANCE: Early adolescence is a good target age to learn and develop muscular control; balance, strength; flexibility; and jumping, running, and landing control. This time of physical and athletic growth may therefore be an appropriate period to influence biomechanical factors and thereby task execution and the injury risk.

Preferred posture in lying and its association with scoliosis and windswept hips in adults with cerebral palsy.

Objective: The aim of this study was to clarify the association of scoliosis and windswept hips with immobility, lying position, and time in lying, in adults with cerebral palsy (CP).Methods: This cross-sectional study included 830 adults (469 males and 361 females) with a diagnosis of CP, 16-73 years, and classified at levels I-V according to the Gross Motor Function Classification System (GMFCS). Subjects' Gross motor function classification system level, presence and severity of scoliosis, hip and knee joint range of movement, lying position, postural ability in lying, and time in lying were used to identify connections between them.Results: Adults who are immobile in the lying position have higher odds of both scoliosis and windswept hips. Spending more than 8 h daily in the same lying position, increased the odds of having scoliosis, while lying solely in a supine position, resulted in higher odds of windswept hips.Conclusions: The "preferred" habitual posture frequently observed in immobile adults with CP, leads to established distortion of their body shape. The results indicate the need for early introduction of appropriate posture control, in immobile individuals with CP, from a young age.Implications for rehabilitationThe preferred posture, observed in immobile adults with cerebral palsy, leads to a distortion of their body shape.One in four adults with cerebral palsy use only one position when in bed.The results indicate the need for early introduction of appropriate posture control in individuals unable to change position.