Inter-rater reliability and test-retest reliability of the Performance and Fitness (PERF-FIT) test battery for children: a test for motor skill related fitness.

BACKGROUND: The Performance and Fitness (PERF-FIT) test battery for children is a recently developed, valid assessment tool for measuring motor skill-related physical fitness in 5 to 12-year-old children living in low-income settings. The aim of this study was to determine: (1) inter-rater reliability and (2) test-retest reliability of the PERF-FIT in children from 3 different countries (Ghana, South Africa and the Netherlands). METHOD: For inter-rater reliability 29 children, (16 boys and 13 girls, 6-10 years) were scored by 2 raters simultaneously. For test-retest reliability 72 children, (33 boys and 39 girls, 5-12 years) performed the test twice, minimally 1 week and maximally 2 weeks apart. Relative and absolute reliability indices were calculated. ANOVA was used to examine differences between the three assessor teams in the three countries. RESULTS: The PERF-FIT demonstrated excellent inter-rater reliability (ICC, 0.99) and good test-retest reliability (ICC, ≥ 0.80) for 11 of the 12 tasks, with a poor ICC for the Jumping item, due to low spread in values. A significant difference between first and second test occasion was present on half of the items, but the differences were small (Cohen's d 0.01-0.17), except for Stepping, Side jump and Bouncing and Catching (Cohen's d 0.34, 0.41 and 0.33, respectively). Overall, measurement error, Limits of Agreement and Coefficient of Variation had acceptable levels to support clinical use. No systematic dissimilarities in error were found between first and second measurement between the three countries but for one item (Overhead throw). CONCLUSIONS: The PERF-FIT can reliably measure motor skill related fitness in 5 to 12-year-old children in different settings and help clinicians monitor levels of fundamental motor skills (throwing, bouncing, catching, jumping, hopping and balance), power and agility.

Feasibility and content validity of the PERF-FIT test battery to assess movement skills, agility and power among children in low-resource settings.

BACKGROUND: Numerous movement skills and physical fitness tests have been developed for children in high-income countries. However, adaptation of these tests to low-resource settings has been slow and norms are still unavailable for children living in low-income communities. The aim of this paper was to describe the development and validation of the Performance and Fitness (PERF-FIT) test battery, a new test to assess motor skill-related physical fitness in children in low-resource settings. METHOD: The PERF-FIT test was developed in a stepwise manner. This involved defining the relevant domains of the construct of interest and selecting and evaluating test items. The Content Validity Index (CVI) was used to estimate content validity. Following development of the PERF-FIT test, a preliminary study was performed to validate items and to examine the feasibility of implementing the test in a low-resource community. Structural validity was also determined based on data from eighty (n = 80) children (aged 7-12 years) using principal component analysis. RESULTS: The CVI for the throw and catch item was 0.86 and 1.00 for the other nine items, leading to a total CVI score of 0.99. The hierarchical sequence of the item series was demonstrated by highly significant (p < 0.001) linear trends, confirming the increase in difficulty of subsequent items. Principal component analysis revealed three factors; the first component is represented by locomotor skills that require static and dynamic balance, the second component by throwing and catching items and the third component by agility and power items. These findings suggest that it is feasible to implement the PERF-FIT in low-resource settings. CONCLUSION: The PERF-FIT test battery is easy to administer and may be suitable for measuring skill-related physical fitness in in low-resource settings. It has excellent content validity and good structural validity. After minor adaptions, further studies should be conducted to establish normative values, evaluate reliability, and document criterion and cross-cultural validity of this test.

Relearning of Writing Skills in Parkinson's Disease After Intensive Amplitude Training.

BACKGROUND: Micrographia occurs in approximately 60% of people with Parkinson's disease (PD). Although handwriting is an important task in daily life, it is not clear whether relearning and consolidation (ie the solid storage in motor memory) of this skill is possible in PD. The objective was to conduct for the first time a controlled study into the effects of intensive motor learning to improve micrographia in PD. METHODS: In this placebo-controlled study, 38 right-handed people with PD were randomized into 2 groups, receiving 1 of 2 equally time-intensive training programs (30 min/day, 5 days/week for 6 weeks). The experimental group (n = 18) performed amplitude training focused at improving writing size. The placebo group (n = 20) received stretch and relaxation exercises. Participants' writing skills were assessed using a touch-sensitive writing tablet and a pen-and-paper test, pre- and posttraining, and after a 6-week retention period. The primary outcome was change in amplitude during several tests of consolidation: (1) transfer, using trained and untrained sequences performed with and without target zones; and (2) automatization, using single- and dual-task sequences. RESULTS: The group receiving amplitude training significantly improved in amplitude and variability of amplitude on the transfer and automatization task. Effect sizes varied between 7% and 17%, and these benefits were maintained after the 6-week retention period. Moreover, there was transfer to daily life writing. CONCLUSIONS: These results show automatization, transfer, and retention of increased writing size (diminished micrographia) after intensive amplitude training, indicating that consolidation of motor learning is possible in PD. © 2016 International Parkinson and Movement Disorder Society.

Motor imagery training for children with developmental coordination disorder--study protocol for a randomized controlled trial.

BACKGROUND: Previous studies have shown that the predictive control of movements is impaired in children with Developmental Coordination Disorder (DCD), most likely due to a deficit in the internal modeling of movements. Motor imagery paradigms have been used to test this internal modeling deficit. The aim of the present study is to examine whether a training focused on the mental imagery of motor skills, can help to improve the motor abilities of children with DCD. METHODS/DESIGN: A pre-post design will be used to examine the motor performance, motor imagery and motor planning abilities before and after a training of 9 weeks. Two groups will be included in this study (1) one receiving motor imagery (MI) training focused on the forward modeling of purposive actions, (2) one receiving Cognitive Orientation to daily Occupational Performance (CO-OP) training focused on identifying effective cognitive strategies that will increase motor competence. MI training will be given with the use of instruction videos of the motor skill that will be trained. Both groups will participate in 9 individual sessions of 45 min (once a week) with a paediatric physical or occupational therapist, added with homework sessions. Inclusion criteria are: (1) aged 7-12 years, (2) meeting the DSM-V criteria for DCD (motor performance substantially low (score on the m-ABC ≤ 16th percentile) and motor problems that interfere with daily life (DCDQ, and request for help at a paediatric physical or occupational therapist)). Exclusion criteria are IQ < 70 and other medical conditions causing the motor impairment. DISCUSSION: The results of this study will help to make treatment protocols for children with DCD more evidence-based. This study will increase our knowledge about the efficacy of both the MI training and CO-OP training, and both children with DCD and therapists will benefit from this knowledge. TRIAL REGISTRATION: www.trialregister.nl/NTR5471.

Health Promotion in a Low-income Primary School: Children with and Without DCD Benefit, but Differently.

UNLABELLED: Poor motor performance and reduced physical fitness are characteristic of children with Developmental Coordination Disorder (DCD). These features have also been identified more frequently among children living in low socio-economic circumstances. AIMS: To evaluate the outcomes of a nine-week health promotion program (HPP) on the motor performance and fitness levels of children (6-10 years) with and without DCD attending a low-income primary school. METHODS: The HPP was designed and implemented by undergraduate physiotherapy students using guidelines from the World Health Organization School Health Initiative and their physiotherapy curriculum. Children with DCD (n = 22) and a control group without DCD (n = 19) participated in the evaluation. Motor skill, functional strength, aerobic capacity, and anaerobic power were measured at baseline and after nine weeks. RESULTS: Both groups of children improved on all measures at the conclusion of the HPP. Children with DCD showed greater improvement than the control group in motor performance and the control group showed greater improvement on one of the anaerobic fitness outcomes. CONCLUSIONS: A school-based HPP that focuses on increasing opportunities for physical activity may be effective in improving motor performance in children with DCD and can increase fitness levels in general.

Intensive training programme improves handwriting in a community cohort of people with Parkinson's disease.

BACKGROUND: People with Parkinson's disease (PwP) often report problems with their handwriting before they receive a formal diagnosis. Many PwP suffer from deteriorating handwriting throughout their illness, which has detrimental effects on many aspects of their quality of life. AIMS: To assess a 6-week online training programme aimed at improving handwriting of PwP. METHODS: Handwriting samples from a community-based cohort of PwP (n = 48) were analysed using systematic detection of writing problems (SOS-PD) by two independent raters, before and after a 6-week remotely monitored physiotherapy-led training programme. Inter-rater variability on multiple measures of handwriting quality was analysed. The handwriting data was analysed using pre-/post-design in the same individuals. Multiple aspects of the handwriting samples were assessed, including writing fluency, transitions between letters, regularity in letter size, word spacing, and straightness of lines. RESULTS: Analysis of inter-rater reliability showed high agreement for total handwriting scores and letter size, as well as speed and legibility scores, whereas there were mixed levels of inter-rater reliability for other handwriting measures. Overall handwriting quality (p = 0.001) and legibility (p = 0.009) significantly improved, while letter size (p = 0.012), fluency (p = 0.001), regularity of letter size (p = 0.009), and straightness of lines (p = 0.036) were also enhanced. CONCLUSIONS: The results of this study show that this 6-week intensive remotely-monitored physiotherapy-led handwriting programme improved handwriting in PwP. This is the first study of its kind to use this tool remotely, and it demonstrated that the SOS-PD is reliable for measuring handwriting in PwP.

Awareness about developmental coordination disorder.

The present paper is designed to promote awareness of DCD outside the academic world. With a prevalence of 5-6% it is one of the most common disorders of child development. It is therefore surprising that so little is known about it among professionals in child healthcare and education. Parents have expressed frustration about this lack of awareness, including the general public. The general aim of this paper was to describe those critical aspects of DCD that will promote awareness.

Noise, variability, and motor performance in developmental coordination disorder.

Variability and noise are a natural part of the neuromuscular system, and can occur at multiple levels. However, excessive neural noise in the motor system makes the problem of control much harder. Disruption of basic sensory inputs will exacerbate the problem, impacting one's sense of position in space (or body schema) and the ability of the motor system to predict its own dynamics. So-called predictive control is fundamental to movement efficiency and accuracy, but has been shown to be poorly developed in children with motor problems like developmental coordination disorder. These children manifest a core deficit in predictive control, which is expressed by high levels of variability across tasks, and at the level of movement kinematics, for example patterns of inter-limb coordination. As such, they rely heavily on feedback mechanisms to exert control, the outcome being slower and more laboured movements, and reduced responsiveness to changes in the environment. We discuss these issues of high variability and noise in developmental coordination disorder in relation to motor prediction, and with an eye to remediation. Issues of task scheduling and use of augmented feedback are important considerations for therapists when treating these children.

Efficacy of interventions to improve motor performance in children with developmental coordination disorder: a combined systematic review and meta-analysis.

AIM: The aim of this study was to review systematically evidence about the efficacy of motor interventions for children with developmental coordination disorder (DCD), and to quantify treatment effects using meta-analysis. METHOD: Included were all studies published between 1995 and 2011 that described a systematic review, (randomized) clinical trial, or crossover design about the effect of motor intervention in children with DCD. Studies were compared on four components: design, methodological quality, intervention components, and efficacy. Twenty-six studies met the inclusion criteria for the review. Interventions were coded under four types: (1) task-oriented intervention, (2) traditional physical therapy and occupational therapy, (3) process-oriented therapies, and (4) chemical supplements. For the meta-analysis, effect sizes were available for 20 studies and their magnitude (weighted Cohen's d [d(w) ]) was compared across training types. RESULTS: The overall effect size across all intervention studies was d(w) =0.56. A comparison between classes of intervention showed strong effects for task-oriented intervention (d(w) =0.89) and physical and occupational therapies (d(w) =0.83), whereas that for process-oriented intervention was weak (d(w) =0.12). Of the chemical supplements, treatment with methylphenidate was researched in three studies (d(w) =0.79) and supplementation of fatty acids plus vitamin E in one study (no effect). The post hoc comparison between treatment types showed that the effect size of the task-oriented approach was significantly higher than the process-oriented intervention (p=0.01) and comparison (p=0.006). No significant difference in the magnitude of effect size between traditional physical and occupational therapy approaches and any of the other interventions emerged. INTERPRETATION: In general, intervention is shown to produce benefit for the motor performance of children with DCD, over and above no intervention. However, approaches from a task-oriented perspective yield stronger effects. Process-oriented approaches are not recommended for improving motor performance in DCD, whereas the evidence for chemical supplements for children with DCD is currently insufficient for a recommendation.

The relationship between joint mobility and motor performance in children with and without the diagnosis of developmental coordination disorder.

BACKGROUND: The purpose of this study was to determine whether joint mobility is associated with motor performance in children referred for Developmental Coordination Disorder (DCD-group) in contrast to a randomly selected group of children between 3-16 years of age (Random-Group). METHODS: 36 children with DCD and 352 typically developing children (Random-Group) participated. Hypermobility was classified based on the Beighton score (cut-off ≥5 for 3-9 years and ≥4 for 10-16 years) using goniometry. Motor performance was assessed with the Movement Assessment Battery for Children (MABC). RESULTS: The mean Beighton score in the DCD-group was 5.0 versus 2.6 in the Random group. Prevalence of hypermobility was higher in the DCD-group than in the Random Group (64% and 33% respectively; χ2 = 16.09, p < .001). There was a significant [negative] correlation (r(p) = -.38, p = .02) between Beighton score and total MABC scores within the DCD group, but not in the Random Group (r(p)= -0.07, p = .20). More specifically, in the DCD group we found a significant negative correlation between the MABC total score and the degree of hyperextension of the knees. CONCLUSION: The extremely high prevalence of hypermobility when applying the recommended cut-off scores stresses the need for an international agreement on firm cut-off points and the use of standardized measurement of Beighton mobility manoeuvres. The results of this study show that a cut-off of 7 is more appropriate, resulting in a prevalence of 6% in children aged 3-16 years. Although in the general population motor performance and joint mobility are not related, this is the case in children referred for DCD. We argue that more mobility of the joints may be a disadvantage when motor coordination is poorly developed.

Injuries in Physical Education Teacher Students: Differences between Sex, Curriculum Year, Setting, and Sports.

Background: Injury risk is high in Physical Education Teacher Education (PETE) students. Insights into specific injury locations per sex, setting, sports, and curriculum year are needed to develop preventive measures. Purpose: To compare injury distributions by body locations in PETE students and how these distributions differ by sex, type, onset, curriculum year, settings, or sports. Methods: In a historical cohort study over 14 years, data from 2899 students (male 76.2%, n = 1947) enlisted in the first three years of a PETE curriculum were analysed. Injuries reported at the institution's medical facility were categorised per sex, body location, onset, type, setting, sports, and curriculum year. Results: Forty-three percent (n = 1247) of all students (female 54.9%, n = 523, male 37.2%, and n = 429) reported a total of 2129 injuries (freshmen 56.4%; 2nd year 28.2%; 3rd year 15.5%). The most prevalent sudden onset injury locations (63.4% of all injuries) were the ankle (32.5%) and knee (16.6). The most prevalent gradual onset injuries were the lower leg (27.8%) and knee (25.2%). Joint/ligament injuries (45.8%) and muscle/tendon injuries (23.4%) were the most prevalent injury types. Proportions for injury locations and injury types differed significantly between curriculum years. Injury prevalence per setting and sport differed significantly between the sexes. Injury locations differed significantly between sports and between the sexes per sport. Conclusion: A differential approach per injury location, onset, type, sex, setting, sports, and curriculum year is needed to develop adequate preventive measures in PETE studies. The engagement of precurricular, intracurricular, and extracurricular stakeholders is needed in the development of these measures.

Insights on action observation and imitation abilities in children with Developmental Coordination Disorder and typically developing children.

BACKGROUND: Children with Developmental Coordination Disorder (DCD) face difficulties in motor learning. Action observation and imitation are strategies frequently used to teach motor skills. AIMS: (1) To study action observation and imitation abilities in children with DCD compared with typically developing peers with a new protocol. (2) To gain insights in the relation between action observation, imitation, motor performance and activities of daily living (ADL). METHOD: Twenty-one children with DCD (mean age 7 years 9 months, range 6-10 years) and 20 age-matched controls (mean age 7 years 8 months, range 6-10 years) were included. A newly developed protocol was used for testing action observation and imitation proficiency. Motor performance were evaluated with the Movement Assessment Battery for Children-2. ADL were investigated with DCD Questionnaire'07. RESULTS: Children with DCD presented significantly lower action observation (p = .037) and imitation abilities (p < .001) than peers. Worse action observation and imitation abilities were related to lower motor performance and ADL skills and a younger age. Non-meaningful gestures imitation proficiency had predictive value for global motor performance (p = .009), manual dexterity (p = .02) and ADL (p = .004). CONCLUSIONS: The new protocol for action observation and imitation abilities can be helpful for detecting motor learning difficulties and for delineating new opportunities for motor teaching approaches in children with DCD.

Efficacy of a Task-Oriented Intervention for Children with a Dual Diagnosis of Specific Learning Disabilities and Developmental Coordination Disorder: A Pilot Study.

BACKGROUND: Task-oriented approaches are recommended for children with developmental coordination disorder (DCD) to address deficits in motor performance and reduce activity limitations. Although this approach is used in several settings, the efficacy of these approaches in children with in dual-diagnosis of specific learning disabilities (SLD) and DCD is less widely known. This study aims to determine the effect of a group-based intervention based on neuromotor task training (NTT) principles on the motor performance of children aged 6-10 years with SLD/DCD. METHODS: A pre-post-test controlled study design was conducted in children with a primary diagnosis of specific learning disabilities (SLD). DCD status was confirmed based on clinical assessment. Children scoring ≤16th percentile on the Motor Assessment Battery for Children 2nd Edition (MABC-2), who also presented with a functional motor problem, according to the MABC checklist were considered as having DCD. Children were allocated to the NTT intervention group based on teachers' perceived notion of need and received two 45-60 min training sessions per week for nine weeks. Children allocated to the usual care (UC) group, received their planned occupational therapy and physical education. The MABC-2 was used to assess changes in motor performance. OUTCOME AND RESULTS: Our numbers confirm that it is crucial to identify the presence of motor coordination difficulties in children who have been diagnosed with SLD. A task-oriented training program based on NTT principles, presented in small groups, has a positive effect on the motor performance in learners with neurodevelopmental disorders and this effect was larger than in the usual care group. CONCLUSION AND IMPLICATIONS: Although using a small group format in children with multiple neurodevelopmental disorders may be challenging for the therapists, it may be a way of delivering services to children in schools for special education. WHAT THIS PAPER ADDS: Children with DCD plus LSD show improvement in their motor skills by performing group-based NTT in the school environment. Group-based NTT shows a significant improvement in the TSS score of the MABC-2 compared to usual care. Children with DCD plus SLD show equal effect sizes after NTT intervention as DCD without SLD.

Validity and reliability of the Movement Assessment Battery for Children-2 Checklist for children with and without motor impairments.

AIM: The aim of this study was to investigate the validity and reliability of the Movement Assessment Battery for Children-2 Checklist (MABC-2). METHOD: Teachers completed the Checklist for 383 children (age range 5-8y; mean age 6y 9mo; 190 males; 193 females) and the parents of 130 of these children completed the Developmental Disorder Coordination Questionnaire 2007 (DCDQ'07). All children were assessed with the MABC-2 Test. The internal consistency of the 30 items of the Checklist was determined to measure reliability. Construct validity was investigated using factor analysis and discriminative validity was assessed by comparing the scores of children with and without movement difficulties. Concurrent validity was measured by calculating correlations between the Checklist, Test, and the DCDQ'07. Incremental validity was assessed to determine whether the Checklist was a better predictor of motor impairment than the DCDQ'07. Sensitivity and specificity were investigated using the MABC-2 Test as reference standard (cut-off 15th centile). RESULTS: The Checklist items measure the same construct. Six factors were obtained after factor analysis. This implies that a broad range of functional activities can be assessed with the Checklist, which renders the Checklist useful for assessing criterion B of the diagnostic criteria for DCD. The mean Checklist scores for children with and without motor impairments significantly differed (p<0.001). The scores for the Checklist/Test and DCDQ'07 were significantly correlated (r(S) =-0.38 and p<0.001, and r(S) =-0.36 and p<0.001, respectively). The Checklist better predicted motor impairment than the DCDQ'07. Overall, the sensitivity was low (41%) and the specificity was acceptable (88%). INTERPRETATION: The Checklist meets standards for validity and reliability.

SOS: a screening instrument to identify children with handwriting impairments.

Poor handwriting has been shown to be associated with developmental disorders such as Developmental Coordination Disorder, Attention Deficit Hyperactivity Disorder, autism, and learning disorders. Handwriting difficulties could lead to academic underachievement and poor self-esteem. Therapeutic intervention has been shown to be effective in treating children with poor handwriting, making early identification critical. The SOS test (Systematic Screening for Handwriting Difficulties) has been developed for this purpose. A child copies a sample of writing within 5 min. Handwriting quality is evaluated using six criteria and writing speed is measured. The Dutch SOS test was administered to 860 Flemish children (7-12 years). Inter- and intrarater reliability was excellent. Test-retest reliability was moderate. A correlation coefficient of 0.70 between SOS and "Concise Assessment Methods of Children Handwriting" test (Dutch version) confirmed convergent validity. The SOS allowed discrimination between typically developing children and children in special education, males and females, and different age groups.

The effects of a visuo-motor and cognitive dual task on walking adaptability in children with and without Developmental Coordination Disorder.

BACKGROUND: Children with Developmental Coordination Disorder (DCD-C) have motor coordination deficits which lead to difficulties in sports and play activities that require adaptations of the walking pattern. Sports and play often involve performing dual tasks, which affects performance in DCD-C more than in typically developing children (TD-C). So far, testing the impact of dual tasking on walking adaptability in DCD-C has received little scientific attention. RESEARCH QUESTION: We tested the hypothesis that 6-12 year old DCD-C will show lower levels of walking adaptability than TD-C, and that due to problems with automatization this difference will increase when they are forced to divide their attention between tasks when a concurrent visuo-motor or cognitive task is added. METHODS: Twenty-six DCD-C and sixty-nine TD-C were included in this cross-sectional study. They performed a challenging walking adaptability (WA) task on a treadmill as a single, a visuo-motor dual and a cognitive dual task at a pace of 3.5 km/h. Repeated measures ANCOVAs were performed with condition (single/dual task) as within-subjects factor, group (TD/DCD) as between-subjects factor, and age as covariate. RESULTS: DCD-C performed poorer on the WA task than TD-C. The group differences increased when a concurrent visuo-motor task was added, but not when adding a concurrent cognitive task. A significant effect of age was found with younger children performing worse on all tasks. SIGNIFICANCE: The results highlight the problems DCD-C have with walking adaptability and dual tasks, which capacities are essential for full participation in sports and play activities. Future research should investigate whether DCD-C may benefit from task-specific walking adaptability training.

Reliability and construct validity of the Walking Adaptability Ladder Test for Kids (WAL-K): a new clinical test for measuring walking adaptability in children.

PURPOSE: Walking adaptability is essential for children to participate in daily life, but no objective measurement tools exist. We determined psychometric properties of the Walking Adaptability Ladder test for Kids (WAL-K) in 6-12 year old children. MATERIALS AND METHODS: In total, 122 typically developing (TD) children and 26 children with Developmental Coordination Disorder (DCD) completed the single and double run conditions of the WAL-K. Intra-rater, inter-rater and test-retest reliability were determined by ICCs and Smallest Detectable Change (SDC) in 53 TD children. Construct validity was determined by comparing WAL-K scores between 69 TD and all DCD children and correlating these scores with age and MABC-2 scores. RESULTS: ICCs for reliability varied between 0.76 and 0.99. Compared to the first test performance, WAL-K scores were lower (i.e., better) at retest. SDCs for test-retest reliability varied between 20.8 and 26.1% of the mean scores. WAL-K scores were significantly higher (i.e., worse) in DCD children compared to TD children (p < 0.001). Significant negative correlations were found with MABC-2 (-0.52 and -0.60) and age (-0.61 and -0.68). CONCLUSIONS: The WAL-K shows to be a valid, reliable and easy-to-use tool for measuring walking adaptability in children. Adding an extra practice trial may reduce the observed learning effect.Implications for rehabilitationWalking adaptability is an essential skill for children to participate in daily life, but no objective measurement tools are available.The Walking Adaptability Ladder test for Kids (WAL-K) is a new measurement tool for evaluating walking adaptability in children.The WAL-K shows to be a reliable and valid measurement tool for evaluating walking adaptability in 6-12 year old children.

Walking adaptability improves after treadmill training in children with Developmental Coordination Disorder: A proof-of-concept study.

BACKGROUND: Children with Developmental Coordination Disorder (DCD) have motor coordination deficits leading to difficulties in sports and play that require adaptations of the walking pattern. Children with DCD indeed demonstrate poorer walking adaptability (WA) compared to typically developing children, but it remains elusive whether WA can be improved by training. RESEARCH QUESTION: Does augmented-reality treadmill training lead to improvements in WA in children with DCD? METHODS: Seventeen children with DCD were included in this proof-of-concept intervention study. They received a six-session training on the C-mill, a treadmill on which gait adjustments can be evoked by projected visual context. The effect of the training was evaluated before (M1), directly after training (M2) and after 6 months follow-up (M3) using the WAL-K (single and double run) and WA-tasks on the C-mill (as a single and with concurrent visuo-motor and cognitive task). In addition, parents completed a questionnaire on their perception of the training. Linear Mixed Model analyses were performed to assess the differences in WAL-K scores and success rates on the WA-tasks between M1-M2 and M1-M3. RESULTS: Children significantly improved on the WAL-K double run and on all three WA-tasks between M1-M2 and M1-M3. Children did not improve on the WAL-K single run. Parents found the training useful and fun for their child and indicated that their child fell less frequently. SIGNIFICANCE: The results show that C-mill training had positive and task-specific effects on WA in children with DCD, which effects generalized to an overground task and were retained at 6 months follow-up. This may help children with DCD to better participate in daily activities. Future research should include a control group to examine the effectiveness of the training program compared to receiving no training and may also examine the effect of the training on participation in daily life.

Neuromuscular training improves knee kinematics, in particular in valgus aligned adolescent team handball players of both sexes.

The purpose of this study was to investigate the effects of added neuromuscular training (NMT), as compared to just regular training (RT), on lower extremity kinematics and single leg stability in adolescent team handball players of both sexes and to investigate whether these effects are more evident in valgus aligned athletes. Eighty adolescent team handball players (NMT: n = 49, RT: n = 31) were tested on knee kinematics in a drop jump and single leg stability in a 1-leg hop test. Based on the initial results in the drop jump test, both groups were subdivided into an above-average valgus aligned (AAVA; NMT: n = 27, RT: n = 22) and a below average valgus aligned (NMT: n = 22, RT: n = 9) group. All groups received 10 weeks of handball training either without (RT) or with in-season NMT. A significant interaction of training and valgus group was found for all absolute and for 2 out of 4 normalized knee distances in the drop jump test (p < 0.024) and for contact time after the first landing (p = 0.029). The AAVA-NMT group showed the largest relative progression (18-37%) for all these parameters. In the 1-leg hop test, a significant effect of NMT compared to RT was found for both legs (p < 0.042). Compared to RT alone, added in-season NMT has the greatest benefits on knee kinematics and single leg stability, in particular in AAVA adolescent team handball players of both sexes. The results of this study suggest that adolescent team handball players of both sexes should be given NMT, 20 minutes twice a week for 10 weeks to improve landing kinematics and single leg stability. "At risk" players with higher initial valgus angles will benefit most from this NMT.

Children with Poor Motor Skills Have Lower Health-Related Fitness Compared to Typically Developing Children.

Most of the current empirical evidence regarding the relationship between health-related fitness and level of motor performance is based on children from high-income countries. Yet, children from low-resource areas may have fewer opportunities to develop their fitness skills. The aim of the study was to determine if South African children from both low- and middle-income areas scoring below the 16th percentile on the Movement Assessment Battery for Children-2 (probable-Developmental Coordination Disorder (p-DCD)) have lower health-related fitness levels than typically developing (TD) children. We hypothesized that children with p-DCD would have lower overall health-related fitness than TD children. A sample of 146 participants aged 10 to 11 (10.05 years (SD = 0.41)) was collected from schools in the North West Province of South Africa, on the basis of their poverty classification. Children were tested for anaerobic capacity and strength using the Bruininks-Oseretsky test of motor proficiency second edition (BOT-2) and aerobic capacity using the Progressive Aerobic Cardiovascular Endurance Run (PACER). Body composition was evaluated using body mass index corrected for age and sex (BMI-z), body fat (BF), and waist circumference. The data was analyzed using Spearman correlations and chi-squared tests. Statistically significant differences (p < 0.05) were found between groups for running and agility, strength, and aerobic capacity. No significant differences were found between p-DCD and TD groups in terms of body mass (36.1 kg vs. 33.3 kg), waist circumference (62.2 cm vs. 59.8 cm), BMI-z (19.7 vs. 17.6), and fat percentage (20.2 vs. 18.1%). Overweight and obesity prevalence was 15% in those with low socio-economic status (SES) and 27% in high SES. In conclusion, children with p-DCD had lower muscular strength, aerobic capacity, and endurance than TD children. Although it has been reported that children with p-DCD have a higher risk for overweight/obesity than TD children, this is not (yet) the case in 10-11-year-old children living in rural areas in South Africa (North West Province).