The multivariate physical activity signature associated with fundamental motor skills in preschoolers.

Physical activity (PA) is essential for development of fundamental motor skills (FMS) in children, but it is uncertain which PA intensities are most influential. A limitation to current evidence is the reliance on analytic approaches that cannot handle collinearity. The aim of this study was to determine the PA signature related to FMS in preschoolers, by investigating the association pattern for the whole spectrum of PA intensities using multivariate pattern analysis. We used a sample of N = 1081 Norwegian preschoolers (4.7 yr; 52% boys) who provided valid accelerometer (ActiGraph GT3X+) and FMS data (TGMD-3, modified version). We created 33 PA variables (from 0-100 to ≥15,000 counts per minute [cpm]), and used partial least squares regression to analyse the associations between PA and FMS, after controlling for potential covariates. PA was positively associated with locomotor- and object control skills (explained variances for vertical axes; R2 = 9.7% and 3.9%, respectively). The strongest associations were found for PA between 5000-8000 cpm. No association pattern was found for PA and balance skills. This study is the first to determine the multivariate PA intensity signature related to FMS. This approach shows that PA within the vigorous range is strongest related to FMS in preschoolers.Abbreviations: FMS: fundamental motor skills; PA: Physical activity; TPA: total physical activity; SED: Sedentary behaviour; LPA: Light physical activity; MPA: Moderate physical activity; VPA: Vigorous physical activity; MVPA: Moderate-to-vigorous physical activity; Min: minutes; cpm: counts per minute; SD: standard deviation; SES: Socioeconomic status; BMI: Body Mass Index.

Children With Developmental Coordination Disorder.

This study tested the effect of task-specific training of a perceptual ability for children with Developmental Coordination Disorder (DCD) compared to control children. A manual matching task (target location and pointing task) was used, which required the children to locate target pins either visually (seen target) or proprioceptively (felt target), while matching to the located target was always carried out without vision. Thirty-one children (11-12 years) were selected based on teacher statements regarding everyday motor skill performance, the DSM-IV criteria, and the Movement ABC test. Based on this, 10 children with obvious motor problems were placed in the DCD group (Trg-DCD), 9 children with no identified motor problems were placed in a training group (Trg-N), and 12 children also with no identified motor problems were placed in a control group. All the children were tested pre and post to training on a manual matching task. In the pretest, the children in the DCD group were significantly inferior to the control groups in the proprioceptive condition with both the preferred and nonpreferred hands. In the posttest, after the training periode was completed, the DCD subjects showed significant improvement in the proprioceptive condition for both preferred and nonpreferred hands. For the other groups, no significant training effects were observed across the training period. It is concluded that children in the DCD group may benefit from specific training of perceptual abilities, because they have motor control resources not exploited due to a lack of relevant experience.

Development of proprioceptive sensitivity.

The development of proprioceptive sensitivity was studied in 140 children between the ages of 5.8 and 11.8 years using a so-called foot-hand task. Ten boys and ten girls were included in each age group. The task required the children to locate a target pin with the "big toe" (felt target) and match the located target position with the hand, without vision. There were four conditions: location of targets by the right big toe: matching located target position with the right hand (RfRh) and left hand (RfLh); and location of targets by the left big toe: matching located target position with the left hand (LfLh) and right hand (LfRh). The results showed a significant developmental trend in proprioceptive sensitivity, when the absolute error scores for boys and girls were combined, with most of the improvement occurring between the ages of 5.8 and 7.8 years. The most interesting and novel finding seems to be the significant two-way interaction between age and sex--the clearest differences manifesting themselves in the age group 9.9 years. Separate within-sex group analyses showed the trend to be determined by the results for the girls, the trend being absent in the results for the boys. Furthermore only the boys showed a significant difference between the intra- and inter-hemispheric conditions. We propose that these differences may only manifest themselves in particular tasks, i.e. there may be a sex-task interaction. The implications of this proposal for theoretical interpretations of the phenomenon of inter-hemispheric processing as well as possible sources of the task differences are briefly discussed.