The purpose of this study was to examine the kinetics of the walk-to-run transition (WRT) and run-to-walk transition (RWT), when accelerating or decelerating across transition speed (a = 0.17 m·s−2). Nine women performed gait transitions on a 50-m-long walkway. Vertical ground reaction forces (GRFs) and the center of pressure (COP) were examined in the range from 3 steps before to 3 steps after transition in order to identify the possible occurrence of a transition process, in order to facilitate the actual realization of transition. The actual transition is realized in one step, during WRT and RWT. This transition step was characterized by an outlying vertical GRF and COP trajectory (deviating from walking and running). Despite this clear discontinuity, a transitional adaptation period (process) appeared in both transitions. In the WRT, transition was prepared and kinetic adaptations were found in the last step before transition. The RWT was pre- and “post”-pared and only completed during the first walking step after transition. Thus, the WRT and RWT are two distinct phenomena, with different kinetics.
Veerle Segers, Peter Aerts, Matthieu Lenoir, and Dirk De Clercq
Eva D’Hondt, Fotini Venetsanou, Antonis Kambas, and Matthieu Lenoir
The targeted continent and/or country driven promotion of physical activity and health from an early age onwards requires more insight into cross-cultural differences in motor competence. Using the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition Short Form (BOT-2 SF), this study assessed and compared both fine and gross motor skill performances of 5- and 6-year-old children from Belgium (n = 325) and Greece (n = 245). Linear mixed effect models and a χ2 test analyzed between-country differences in BOT-2 SF scores and the distribution across descriptive performance categories. Overall, Belgian and Greek participants displayed quite similar levels of motor competence, with fewer children performing (well-)below average than could be expected. On test item level, however, several significant differences emerged. Large effect sizes were found for knee push-ups (Hedges’ g = 1.46) and copying a square (Hedges’ g = 2.59), which demonstrated a better outcome for Belgian and Greek preschoolers, respectively. These findings might be attributed to different (physical) education practices in both European countries. The present study also highlights the importance of using an assessment tool covering the entire range of motor skills as well as a focusing primarily on raw performance scores, containing and explaining more variance, for international comparative research purposes.
Jorge Cottyn, Dirk de Clercq, Geert Crombez, and Matthieu Lenoir
Preparatory heart rate deceleration occurs in tasks with an external focus of attention and is often assumed to facilitate balance performance. However, its effects upon sport-related complex balance movements have not been studied. Heart rate patterns during the preparation period of an acrobatic element (flic-flac) on the balance beam were studied in 14 female gymnasts (M age 13.2 years). A significant heart rate deceleration was found in attempts with a fall in the consecutive acrobatic element, but not in attempts without a fall. These data suggest that preparatory heart rate deceleration may be detrimental to the performance of complex movements on the balance beam.
Fabian Ducheyne, Ilse De Bourdeaudhuij, Matthieu Lenoir, and Greet Cardon
This study examined the reliability of a newly developed child and parental questionnaire on specific determinants of cycling to school among 10–12 year olds. Validity of child reported distance, bicycle equipment and basic bicycle skills was also investigated. In total 211 children and 33 parents participated in this study. The reliability of the questionnaires was acceptable with results indicating reliability ranging from fair to perfect agreement. Therefore, the questionnaires appear to be reliable tools for assessing specific determinants of cycling to school. Furthermore, it was found that children overestimate their abilities to perform basic bicycle skills. This suggests that objectively measuring bicycle skills is preferred to child reported skills assessment.
Brigit De Wit, Dirk De Clercq, and Matthieu Lenoir
The purpose of this study was to investigate the influence of midsole hardness on both impact forces and rearfoot motion. Seven trained male long-distance runners were assessed with a Kistler force plate and with high-speed video, while running at 4.5 ± 0.1 m · s"1 with soft and hard shoe soles (EVA; soft shore Asker C40; hard shore Asker C65). The results showed smaller initial vertical impact peaks, occurring with a higher loading rate, and a significantly larger and faster initial eversion when subjects ran with hard shoes. Support is given to the concept that a more pronounced initial eversion offers an additional deceleration mechanism (Stacoff, Denoth, Kaelin, & Stuessi, 1988) also increasing the eccentric loading of the inverting muscles. On the other hand, during midstance soft shoe soles were found to produce a larger maximum eversion and pronation, also imposing an increased load on the same muscles. So, a good running shoe should be focused on a balance between reducing impact forces and reducing overpronation.
Eva D’Hondt, Benedicte Deforche, Ilse De Bourdeaudhuij, and Matthieu Lenoir
The purpose of this study was to investigate gross and fine motor skill in overweight and obese children compared with normal-weight peers. According to international cut-off points for Body Mass Index (BMI) from Cole et al. (2000), all 117 participants (5–10 year) were classified as being normal-weight, overweight, or obese. Level of motor skill was assessed using the Movement Assessment Battery for Children (MABC). Scores for balance (p < .01) and ball skills (p < .05) were significantly better in normal-weight and overweight children as compared with their obese counterparts. A similar trend was found for manual dexterity (p < .10). This study demonstrates that general motor skill level is lower in obese children than in normal-weight and overweight peers.
Roel Vaeyens, Matthieu Lenoir, A. Mark Williams, Liesbeth Mazyn, and Renaat M. Philippaerts
We examined differences in visual search behaviors and decision-making skill across different microstates of offensive play in soccer using youth participants (13.0-15.8 years) varying in skill and experience. We used realistic film simulations of offensive play, movement-based response measures, and an eye movement registration technique. Playing experience, skill level, and the unique constraints of the task, expressed by the number of players and relative proportion of offensive and defensive players, determined both the observed search behavior and processing requirements imposed on players in dynamic offensive team simulations. Significant differences in performance were observed between players and nonplayers and across three groups of soccer players who differed in skill level. Implications for talent identification and development are considered.
Liesbeth I.N. Mazyn, Gilles Montagne, Geert J.P. Savelsbergh, and Matthieu Lenoir
In the present study, the limits of human catching behavior were challenged to investigate quantitative and qualitative adaptations of the catching movement when performing under varying ball speeds, implying minor as well as severe temporal constraints. Nine male participants caught balls approaching at speeds ranging from 8.5 to 19.7 m/s with their preferred hand. Although a decrease in catching performance was undeniable, several quantitative adaptations provided the catcher with extra time and allowed to compensate the decrease in spatial accuracy with increasing speed. More importantly, changes in the coordination between hand, elbow, and shoulder emerged with increasing movement velocity. More demanding temporal constraints lead to a shift from relatively independent activity of each joint towards a mode in which several joints act as one unit. This reorganization of the coordination pattern of the catch is discussed in the context of Bernstein’s degrees of freedom problem.
Philip W. Fink, Sarah P. Shultz, Eva D’Hondt, Matthieu Lenoir, and Andrew P. Hills
Multifractal analyses have been used in recent years as a way of studying balance, with the goal of understanding the patterns of movement of the center of pressure at different spatial scales. A multifractal detrended fluctuation analysis was used to compare obese and nonobese children to investigate the cause of previously demonstrated deficiencies in balance for obese children. Twenty-two children (11 obese and 11 nonobese), aged 8–15 years, performed 30-s trials of bilateral static balance on a plantar pressure distribution measuring device. Both the obese and nonobese groups demonstrated greater persistence for small fluctuations, but the effect was greater in the obese group. This was particularly evident with the eyes closed, where significant differences between the obese and nonobese were observed for small fluctuations. These results demonstrate that balance deficiencies in obese children may be the result of decreased proprioceptive abilities in obese children.
Pieter Tijtgat, Jos Vanrenterghem, Simon J. Bennett, Dirk De Clercq, Geert J.P. Savelsbergh, and Matthieu Lenoir
The purpose of this study was to investigate postural adjustments in one-handed ball catching. Specifically, the functional role of anticipatory postural adjustments (APA) during the initial arm raising and subsequent postural adjustments (SPA) for equilibrium control and ball-hand impact were scrutinized. Full-body kinematics and kinetics allowed an analysis of the mechanical consequences of raising up the arm and preparing for ball-hand impact. APA for catching were suggested to be for segment stabilization. SPA had a functional role for equilibrium control by an inverted pendulum mechanism but were also involved in preparing for the impact of the ball on the hand, which was illustrated by an increased postural response at the end of the movement. These results were compared with raising up the arm in a well-studied reaction-time task, for which an additional counter rotation equilibrium mechanism was observed. Together, our findings demonstrate that postural adjustments should be investigated in relation to their specific functional task constraints, rather than generalizing the functional role of these postural adjustments over different tasks.