Convergent and divergent validity between the KTK and MOT 4-6 motor tests in early childhood

The aim of this study was to investigate the convergent and divergent validity between the Body Coordination Test for Children (KTK) and the Motor Proficiency Test for 4- to 6-Year-Old Children (MOT 4-6). A total of 638 children (5-6 yr old) took part in the study. The results showed a moderately positive association between the total scores of both tests (r = .63). Moreover, the KTK total score correlated more highly with the MOT 4-6 gross motor score than with the MOT 4-6 fine motor score (r = .62 vs. .32). Levels of agreement were moderate when identifying children with moderate or severe motor problems and low at best when detecting children with higher motor-competence levels. This study provides evidence of convergent and divergent validity between the KTK and MOT 4-6. However, given the moderate to low levels of agreement, either measurement may lead to possible categorization errors. Children's motor competence should therefore not be judged based on the result of a single test

The positive effect of mirror visual feedback on arm control in children with Spastic Hemiparetic Cerebral Palsy is dependent on which arm is viewed

Mirror visual feedback has previously been found to reduce disproportionate interlimb variability and neuromuscular activity in the arm muscles in children with Spastic Hemiparetic Cerebral Palsy (SHCP). The aim of the current study was to determine whether these positive effects are generated by the mirror per se (i.e. the illusory perception of two symmetrically moving limbs, irrespective of which arm generates the mirror visual feedback) or by the visual illusion that the impaired arm has been substituted and appears to move with less jerk and in synchrony with the less-impaired arm (i.e. by mirror visual feedback of the less-impaired arm only). Therefore, we compared the effect of mirror visual feedback from the impaired and the less-impaired upper limb on the bimanual coupling and neuromuscular activity during a bimanual coordination task. Children with SHCP were asked to perform a bimanual symmetrical circular movement in three different visual feedback conditions (i.e. viewing the two arms, viewing only one arm, and viewing one arm and its mirror image), combined with two head orientation conditions (i.e. looking from the impaired and looking from the less-impaired body side). It was found that mirror visual feedback resulted in a reduction in the eccentric activity of the Biceps Brachii Brevis in the impaired limb compared to the condition with actual visual feedback from the two arms. More specifically, this effect was exclusive to mirror visual feedback from the less-impaired arm and absent when mirror visual feedback from the impaired arm was provided. Across conditions, the less-impaired arm was the leading limb, and the nature of this coupling was independent from visual condition or head orientation. Also, mirror visual feedback did not affect the intensity of the mean neuromuscular activity or the muscle activity of the Triceps Brachii Longus. It was concluded that the positive effects of mirror visual feedback in children with SHCP are not just the result of the perception of two symmetrically moving limbs. Instead, in order to induce a decrease in eccentric neuromuscular activity in the impaired limb, mirror visual feedback from the ‘unaffected’ less-impaired limb is required

Assessing fundamental motor skills in Belgian children aged 3-8 years highlights differences to US reference sample

AIM: This study aimed to understand the fundamental motor skills (FMS) of Belgian children using the process-oriented Test of Gross Motor Development, Second Edition (TGMD-2) and to investigate the suitability of using the United States (USA) test norms in Belgium. METHODS: FMS were assessed using the TGMD-2. Gender, age and motor performance were examined in 1614 Belgian children aged 3-8 years (52.1% boys) and compared with the US reference sample. RESULTS: More proficient FMS performance was found with increasing age, from 3 to 6 years for locomotor skills and 3 to 7 years for object control skills. Gender differences were observed in object control skills, with boys performing better than girls. In general, Belgian children had lower levels of motor competence than the US reference sample, specifically for object control skills. The score distribution of the Belgian sample was skewed, with 37.4% scoring below average and only 6.9% scoring above average. CONCLUSION: This study supported the usefulness of the TGMD-2 as a process-oriented instrument to measure gross motor development in early childhood in Belgium. However, it also demonstrated that caution is warranted when using the US reference norms

The effectiveness of a fundamental motor skill intervention in pre-schoolers with motor problems depends on gender but not environmental context

This study evaluated the effect of a 10-week fundamental motor skill programme in pre-schoolers with motor problems. Alongside the general effect of the intervention, we also explored possible gender differences and the role of the environmental context (living community, socio-economic status, and recreational space inside/outside the house). The intervention group (n=47; 20 ♂ and 27 ♀) received twenty 60-min motor skill sessions (2 per week) in addition to the regular physical education curriculum for pre-schoolers; the control group (n=46; 21 ♂ and 25 ♀) did not receive additional practice. General motor competence, and locomotor and object control subscales, were assessed before and after the intervention using the Test of Gross Motor Development 2nd edition (TGMD-2). Data regarding environmental factors were gathered through a questionnaire. A Group×Gender×Time ANOVA revealed that the intervention group benefited significantly from the intervention and scored better than the control group at the post-test for general motor competence and both sub-categories (locomotor and object control skill). Moreover, the intervention programme was found to be effective in helping 49% of the intervention group to achieve an average motor skill level, according to the TGMD-2 norms, while a further decline in motor competence was observed in the control group. Interestingly, the effect appeared to be gender-specific, since object control skill improved only in girls of the intervention group. Considering the environmental context, none of the above-mentioned factors was found to have an influence on the effectiveness of the intervention. The present study highlights the need for an early motor skill programme with a gender-specific approach in order to help low skilled boys and girls master a diverse set of motor skills

Is developmental coordination disorder a motor imagery deficit?

This study investigated the notion that children with developmental coordination disorder (DCD) show a reduced capacity of internally simulating movements of their own body or motor imagery. Using a mental rotation paradigm the contribution of hand posture to laterality/mirror judgments of bodily and alphanumeric stimuli was studied in 13 children with DCD and 13 matched typically developing (TD) children. Children were asked to judge whether the stimulus on display, rotated over -90 degrees, -30 degrees, +30 degrees, or +90 degrees, was a right or left hand or a canonical or mirror-reversed letter. Analysis of accuracy (ACC) and response times (RTs) demonstrated that children with DCD were generally slower and made more errors. RTs to letter stimuli were faster than those to hand stimuli in both DCD and TD children. For both groups RTs profiles were influenced by the orientation of the stimulus, showing longer response times for larger rotations. Clockwise rotations of right hands resulted in slower judgments than did counterclockwise rotations, whereas the reverse was true for left hands. Moreover, the results also indicate a contribution of hand posture to the laterality judgments of hands, with longer RTs when the posture of the participants' hands was opposite to the posture of the hands on display. Importantly, these effects that suggest an imagery strategy engaging motor processes were present in both groups. Apparently, the children with DCD of the present study did rely on motor imagery to solve the mental rotation task; however, their judgments seem to be compromised by a less well-defined internal model

Identification of elite performance characteristics in a small sample of taekwondo athletes

Along with the increasing popularity of taekwondo, there is a need of evidence-based talent identification (TID) and development programs based upon profiles of future elite athletes. This study first aims to investigate the differences between elite and non-elite taekwondo athletes in anthropometry, physical performance and motor coordination. The second aim is to demonstrate the applicability of z-scores in TID research. A total of 98 Taekwondo athletes between 12 and 17 years old were tested using a generic test battery consisting of four anthropometrical (Height, Weight, Fat Percentage, BMI), six physical performance (Sit & Reach, Sprint 5m, Sprint 30m, Counter Movement Jump, Squat Jump, Endurance Shuttle Run) and three motor coordination tests (Moving Sideways, Jumping Sideways, Walking Backwards). Based on the individual success at international competition level, 18 were categorised as elite athletes and 80 were considered as non-elite. T-tests (step 1) on raw test scores and MANOVAs on z-scores (step 2) were conducted to examine differences between the elite and non-elite taekwondo athletes for anthropometry, physical performance and motor coordination tests. Finally, z-scores were reconverted to raw scores to demonstrate practical significance for coaches. Overall, elite taekwondo athletes score better compared to the non-elite group. The MANOVA analysis better scores for elites on fat percentage (-0.55 versus 0.12;p = 0.006), BMI (-0.37 versus 0,08;p = 0.067) sprint speed 30m (-0.48 versus 0.11;p = 0.029), counter movement jump (0.79 versus -0.18;p = 0.000), squat jump (0.42 versus -0.11;p = 0.041), moving sideways (0.79 versus -0.18;p = 0.000) and walking backwards (0.54 versus -0.12;p = 0.006). This study confirms our knowledge on physical profiles of elite taekwondo athletes and expands our knowledge to the domain of motor coordination. This study showed how the z-score method can be used to distinguish between elite and non-elite athletes, the former being low in number by definition

Reduced motor competence in children with obesity is associated with structural differences in the cerebellar peduncles

Previous studies have suggested that neurological factors partly explain the reduced motor competence found in many children with obesity. Accordingly, the aim of this study was to compare motor competence and white matter organization of important pathways for motor control (cerebellar peduncles) in children with and without obesity. Nineteen children with obesity and 25 children with a healthy weight, aged 7–11 years old, were included. Anthropometric measurements were taken and the level of motor competence was assessed using the Movement Assessment Battery for Children (2nd Edition). Children’s brain was scanned using diffusion weighted imaging preceded by a standard anatomical scan. Fractional anisotropy and mean diffusivity were extracted from the cerebellar peduncles. Obese children’s level of motor competence was significantly lower than that in healthy weight peers (p  <  0.05). Additionally, significant group differences (p  <  0.05) were found for values of fractional anisotropy, but not for mean diffusivity. Further analyses revealed that lower values of fractional anisotropy in the inferior (p = 0.040) and superior (p = 0.007) cerebellar peduncles were present in children with obesity compared to children with a healthy weight. After controlling for multiple comparisons (p  <  0.0167), only significant differences in the superior cerebellar peduncle remained significant. Our results showed that childhood obesity is accompanied by reduced motor competence and alterations in white matter organization. This suggests that the motor difficulties of children with obesity are not solely due to carrying excess weight, which may have implications for prevention and intervention programs

Role of motor competence and executive functioning in weight loss: A study in children with obesity

Objective: This study aimed to compare motor competence and executive functioning (EF) between children with obesity and peers with healthy weight. Additionally, the predictive value of motor competence and EF in weight loss after a 5-month multidisciplinary residential treatment program was examined. Methods: Thirty-two children with obesity (7–11 years, 14 boys) and 32 age-matched controls (18 boys) performed 8 motor skill tasks and 4 tasks of EF (only at baseline). In the group of children with obesity, anthropometric measurements were performed at baseline and 5 months after the start of their treatment program. Also in control children, there was a time span of 5 months in between anthropometric measurements. Results: Lower levels of motor competence and reduced updating abilities, inhibition control, and planning skills were observed in children with obesity compared with healthy-weight controls. Within the total group, better general motor competence and balance skills were significantly associated with better updating, inhibition control, and planning. Finally, hierarchical regression analyses revealed that ball skills, balance skills, and inhibition/updating at baseline predicted 14% to 17% of the variance in weight loss after a 5-month treatment program in children with obesity. Conclusion: These results suggest that motor competence and EF are both relevant factors associated with childhood obesity. Moreover, these factors seem to be significant predictors of weight loss. Future (intervention) studies are needed to understand the impact of the difficulties in motor and EF on obesity-related behaviors as well as on short-term and, especially, longterm weight loss and maintenance

The effects of age, biological maturation and sex on the development of executive functions in adolescents

The development of executive functions (EF) has been widely investigated and is associated with various domains of expertise, such as academic achievement and sports performance. Multiple factors are assumed to influence the development of EF, among them biological maturation. Currently the effect of biological maturation on EF performance is largely unexplored, in contrast to other domains like physical development or sports performance. Therefore, this study aimed (a) to explore the effect of chronological age on EF performance and (b) to investigate to what extent age-related changes found in EF are affected by biological maturation on both sexes. To this end, EF performance and degree of maturity, indexed by percentage of predicted adult height (%PAH), of 90 adolescents (11-16 years old, 54% males) were measured on three occasions in a time frame of 12 months. A Generalized Estimating Equation (GEE) approach was used to examine the association between chronological age and %PAH and the weighted sum scores for each EF component (i.e., inhibition, planning, working memory, shifting). All models were run separately for both sexes. The males' results indicated that EF performance improved with age and degree of maturity on all four components. Interaction effects between age and %PAH on inhibition showed that at a younger age, males with a higher %PAH had a lower chance of performing well on inhibition, whereas at later ages, males with a higher %PAH had a higher chance to have a good inhibition performance. For working memory, it seems that there is no maturity effect at a younger age, while at later ages, a disadvantage for later maturing peers compared to on-time and earlier maturing male adolescents emerged. Females showed slightly different results. Here, age positively influenced EF performance, whereas maturity only influenced inhibition. Interaction effects emerged for working memory only, with opposite results from the males. At younger ages, females with lower %PAH values seem to be scoring higher, whereas at later ages, no maturity effect is observed. This study is one of the first to investigate the effect of biological maturation on EF performance, and shows that distinct components of EF are influenced by maturational status, although the effects are different in both sexes. Further research is warranted to unravel the implications for maturation-driven effects on EF that might significantly affect domains of human functioning like academic achievement and social developmen