2022, Article / Letter to editor (CHILDREN-BASEL, vol. 9, iss. 7, (2022))Gross motor coordination (GMC) is essential for the development of specific motor skills and long-term participation in physical activities and sports. Group analysis reveals that, on average, children develop these skills gradually; however, how individuals develop GMC is less clear. The main aim of this study is to increase the understanding of developmental patterns within one school year, and whether children's grade, gender, or baseline GMC proficiency are associated with these developmental patterns. In total, 2594 Dutch children aged 6-12 years performed the modified Korper Koordinations Test fur Kinder (KTK3+) twice in one school year (autumn and spring). The KTK3+ includes four subtests: walking backwards, moving sideways, jumping sideways, and eye-hand coordination (EHC) test. On average, children developed significantly on all subtests (p < 0.001). At baseline, children in higher grades scored significantly higher than children in lower grades, and children in grades 5 and 6 (age 9 and 10 years) showed most development (raw scores on average, p < 0.001). Boys outperformed girls on EHC across all grades, whereas girls outperformed boys on walking backwards. Nevertheless, both boys and girls developed similarly. Children with lower scores at baseline developed more quickly across all grades. Noteworthy is that 12.1-24% (depending on the test item) of the children scored lower in the spring than in the autumn tests. On average, children develop their GMC; however, we report large differences in their individual trajectories and note that a substantial number did not show a positive GMC development. Further research should examine GMC development with more possible influencing factors as well as over a longer time span to better understand differences in children's GMC development. This may result in more individualized programs in PE lessons, enabling children to optimally develop their GMC, and better use of GMC assessment tools to monitor children's development.
2021, Article / Letter to editor (European Journal of Sport Science, vol. 21, iss. 6, (2021), pp. 871-878)Purpose: Dietary nitrate has been shown to enhance muscle contractile function and has, therefore, been linked to increased muscle power and sprint exercise performance. However, the impact of dietary nitrate supplementation on maximal strength, performance and muscular endurance remains to be established. Methods: Fifteen recreationally active males (25 ±4 y, BMI 24 ±3 kg/m(2)) participated in a randomized double-blinded cross-over study comprising two 6-d supplementation periods; 140 mL/d nitrate-rich (BR; 985 mg/d) and nitrate-depleted (PLA; 0.37 mg/d) beetroot juice. Three hours following the last supplement, we assessed countermovement jump (CMJ) performance, maximal strength and power of the upper leg by voluntary isometric (30° and 60° angle) and isokinetic contractions (60, 120, 180 and 300°•s(-1)), and muscular endurance (total workload) by 30 reciprocal isokinetic voluntary contractions at 180°•s(-1). Results: Despite differences in plasma nitrate (BR: 879 ±239 vs. PLA: 33 ±13 μmol/L, Pn<n0.001) and nitrite (BR: 463 ±217 vs. PLA: 176 ±50 nmol/L, Pn<n0.001) concentrations prior to exercise testing, CMJ height (BR: 39.3 ±6.3 vs. PLA: 39.6 ±6.3 cm; Pn=n0.39) and muscular endurance (BR: 3.93 ±0.69 vs. PLA: 3.90 ±0.66 kJ; Pn=n0.74) were not different between treatments. In line, isometric strength (Pn>n0.50 for both angles) and isokinetic knee extension power (Pn>n0.33 for all velocities) did not differ between treatments. Isokinetic knee flexion power was significantly higher following BR compared with PLA ingestion at 60°•s(-1) (Pn=n0.001), but not at 120°•s(-1) (Pn=n0.24), 180°•s(-1) (Pn=n0.066), and 300°•s(-1) (Pn=n0.36). Conclusion: Nitrate supplementation does not improve maximal strength, countermovement jump performance and muscular endurance in healthy, active males.
2016, Article / Letter to editor (Perceptual and Motor Skills, vol. 122, iss. 3, (2016), pp. 871-885)Relatively little is known about how practice relates to children's improvement in gross motor skill performance. The aim of this study is to determine to what extent 6- and 7-year-old children improve their gross motor skill performance in a four-week period, in which goal-directed learning is stimulated and to determine whether differences between boys and girls occur. Groups of 6 year olds (nn=n167) and 7 year olds (nn=n140) practiced their gross motor skill for four weeks. Physical education teachers stimulated goal-directed learning by their instruction, skill-specific exercises, and individual practice. The week before and after, gross motor skill performance was assessed, using the Körper Koordinations Test für Kinder, and compared with a control group (nn=n131). Both 6 and 7 year olds in the intervention group improved their gross motor skill performance significantly more than the control group. The results show the relevance of goal-directed learning for the improvement of gross motor skill performance.
2020, Part of book or chapter of book (Baker, J.; Cobley, S.; Schorer, J. (ed.), Talent Identification and Development in Sport: International Perspectives)
2020, Part of book or chapter of book (Baker, J.; Cobley, S.; Schorer, J. (ed.), Talent Identification and Development in Sport: International Perspectives)
2016, Article / Letter to editor (International Journal of Sports Medicine, vol. 37, iss. 7, (2016), pp. 531-538)The aim of the present study was to identify anthropometric, physical, coordinative and ice-skating specific characteristics that discriminate young elite ice skaters from non-elite skaters and their non-skating peers. 32 skaters aged 9-12 years old (11 elites and 21 non-elites) voluntarily participated in the study. They were submitted to 5 anthropometric, 7 physical, 3 coordination and 5 ice-skating specific tests. Reference values of a representative healthy non-skating sample were taken from the Flemish Sports Compass dataset. Figure skaters appeared to be predominantly average mature (93.8%), were lighter and leaner than the reference sample, and demonstrated better physical characteristics and motor coordination. There was no difference between the elite and non-elite group regarding maturity status and anthropometric or physical parameters. Still, elite skaters scored better than non-elites on the coordination tests jumping sideways and tended to do so on the moving sideways test. Profiles of figure skaters differ clearly from a reference population, while non-sport-specific motor coordination tests allow discrimination between elite and non-elite skaters. The relevance of these findings with respect to talent detection and identification in young ice skaters are discussed.