Individuals with multiple sclerosis (MS) often have poor balance control that is especially apparent during dynamic tasks such as gait initiation (GI). The purpose of this study was to investigate how balance symptoms due to MS alter spatiotemporal variables, coordination, and temporal margins within the stability boundary during gait initiation. Twelve women with MS (Expanded Disability Status Scale [EDSS] mean = 4.0, SD = 1.4) and 12 women without MS (control group) initiated gait at their preferred speed. MS participants attained a slower anterior velocity because of smaller anterior center of mass displacements and took longer to complete the initiation of gait than the control group. MS participants exhibited a smaller posterior shift in center of pressure during GI and stepped with a longer dual support time than the control group. However, these changes may be due to differences in initiation velocity. Relative timing analysis showed invariance in postural and locomotor phases of gait initiation between groups. The MS group showed different coordination between anterior-posterior and medio-lateral center of pressure components while increasing temporal margins to the posterior and lateral stability boundaries in comparison with the control group. Overall, during gait initiation at their preferred speed the MS participants adopted a functional strategy that produces lower speed and reduced proximity to the stability boundaries prior to stepping.
Jebb G. Remelius, Joseph Hamill, Jane Kent-Braun and Richard E.A. Van Emmerik
Kara K. Palmer and Ali Brian
The Test of Gross Motor Development, 2nd edition (TGMD-2), is one of the most widely used measures of motor skill competence. The purpose of this study was to examine if differences in scores exist between expert and novice coders on the TGMD-2 (Ulrich, 2000).
Three coders, one expert and two novices, reviewed and scored young children’s (N = 43; Boys = 57%; Mage = 4.88, SD = 0.28) TGMD-2 data. The kappa statistic was used to determine agreement between expert and novice coders on the locomotor and object control subscale of the TGMD-2. Independent samples t tests and percent differences were then used to examine scoring differences for each of the twelve skills.
Results support that expert and novice coders do not demonstrate significant agreement when scoring the TGMD-2 except for when scoring the kick (t 41 = –1.3, p = .2) and the gallop (t 41= –1.7, p = .09).
This work demonstrates that more stringent or consistent training regimens are needed before allowing novices to code TGMD-2 data.
David I. Anderson, Audun Dahl, Joseph J. Campos, Kiren Chand, Minxuan He and Ichiro Uchiyama
This report describes a novel test of the prediction that locomotion-induced changes in an infant’s functional utilization of peripheral lamellar optic flow (PLOF) for postural stability contributes to avoidance of the deep side of a visual cliff. To test the prediction, a corridor, with either low-textured or high-textured walls, was constructed to run the length of a visual cliff. The infants, 9.5-month-olds with varying amounts of hands-and-knees crawling experience, were randomly assigned to the low-texture (n = 30) or the high-texture condition (n = 32). Consistent with predictions, the findings revealed significant interactions between crawling experience and texture condition for the probability of crossing and the latency to venture onto the deep side of the cliff. Most notably, more experienced crawlers, but not less experienced crawlers, were significantly more likely to cross the visual cliff to the parents and ventured onto the cliff faster in the high-texture condition than in the low-texture condition. The availability of PLOF thus had an effect on infants’ crossing behavior on the visual cliff. We interpret these findings as evidence for a three-step process in which locomotor-induced changes in visual proprioception play a central role in the development of wariness of heights.
Moeko Ueno, Ichiro Uchiyama, Joseph J. Campos, David I. Anderson, Minxuan He and Audun Dahl
Infants show a dramatic shift in postural and emotional responsiveness to peripheral lamellar optic flow (PLOF) following crawling onset. The present study used a novel virtual moving room to assess postural compensation of the shoulders backward and upward and heart rate acceleration to PLOF specifying a sudden horizontal forward translation and a sudden descent down a steep slope in an infinitely long virtual tunnel. No motion control conditions were also included. Participants were 53 8.5-month-old infants: 25 prelocomotors and 28 hands-and-knees crawlers. The primary findings were that crawling infants showed directionally appropriate postural compensation in the two tunnel motion conditions, whereas prelocomotor infants were minimally responsive in both conditions. Similarly, prelocomotor infants showed nonsignificant changes in heart rate acceleration in the tunnel motion conditions, whereas crawling infants showed significantly higher heart rate acceleration in the descent condition than in the descent control condition, and in the descent condition than in the horizontal translation condition. These findings highlight the important role played by locomotor experience in the development of the visual control of posture and in emotional reactions to a sudden optically specified drop. The virtual moving room is a promising paradigm for exploring the development of perception–action coupling.
Viviene A. Temple and John T. Foley
The development of motor skill proficiency during childhood is cumulative and influenced by physical growth and maturation, genetic potential, affordances in the physical and social environment, and the interactions between these factors. Therefore, typically during childhood, the trajectory of change in motor proficiency is positive. To lend developmental validity to the revision of the Test of Gross Motor Development—3rd edition (TGMD-3), this longitudinal study examined whether the skills and subtests of the TGMD-3 changed as might be expected from grade 3 to grade 4 among 277 children. The findings of this study lend support to the developmental validity of the TGMD-3 in that (1) there was within-individual change in the expected direction for both locomotor and ball skills, (2) consistent with the majority of research, boys had significantly higher ball skills scores than girls in both grade 3 and grade 4, and (3) the mean percent of maximum possible scores were in the range of approximately 60–75, which demonstrates that the majority of 8- and 9-year-old children had not reached a ceiling on this test.
Martin Buchheit and Ben Michael Simpson
With the ongoing development of microtechnology, player tracking has become one of the most important components of load monitoring in team sports. The 3 main objectives of player tracking are better understanding of practice (provide an objective, a posteriori evaluation of external load and locomotor demands of any given session or match), optimization of training-load patterns at the team level, and decision making on individual players’ training programs to improve performance and prevent injuries (eg, top-up training vs unloading sequences, return to play progression). This paper discusses the basics of a simple tracking approach and the need to integrate multiple systems. The limitations of some of the most used variables in the field (including metabolic-power measures) are debated, and innovative and potentially new powerful variables are presented. The foundations of a successful player-monitoring system are probably laid on the pitch first, in the way practitioners collect their own tracking data, given the limitations of each variable, and how they report and use all this information, rather than in the technology and the variables per se. Overall, the decision to use any tracking technology or new variable should always be considered with a cost/benefit approach (ie, cost, ease of use, portability, manpower/ability to affect the training program).
James J. Malone, Ric Lovell, Matthew C. Varley and Aaron J. Coutts
Athlete-tracking devices that include global positioning system (GPS) and microelectrical mechanical system (MEMS) components are now commonplace in sport research and practice. These devices provide large amounts of data that are used to inform decision making on athlete training and performance. However, the data obtained from these devices are often provided without clear explanation of how these metrics are obtained. At present, there is no clear consensus regarding how these data should be handled and reported in a sport context. Therefore, the aim of this review was to examine the factors that affect the data produced by these athlete-tracking devices and to provide guidelines for collecting, processing, and reporting of data. Many factors including device sampling rate, positioning and fitting of devices, satellite signal, and data-filtering methods can affect the measures obtained from GPS and MEMS devices. Therefore researchers are encouraged to report device brand/model, sampling frequency, number of satellites, horizontal dilution of precision, and software/firmware versions in any published research. In addition, details of inclusion/exclusion criteria for data obtained from these devices are also recommended. Considerations for the application of speed zones to evaluate the magnitude and distribution of different locomotor activities recorded by GPS are also presented, alongside recommendations for both industry practice and future research directions. Through a standard approach to data collection and procedure reporting, researchers and practitioners will be able to make more confident comparisons from their data, which will improve the understanding and impact these devices can have on athlete performance.
Anthony D. Okely, Michael L. Booth and John W. Patterson
This study investigated a possible relationship between cardiorespiratory endurance and fundamental movement skill proficiency among adolescents. Locomotor (run and jump) and object-control (catch, throw, kick, and strike) skills and cardiorespiratory endurance, indirectly measured using the Multistage Fitness Test (MFT) or PACER, were assessed in 2,026 boys and girls in Grade 8 (mean age = 13.3 years) and Grade 10 (mean age = 15.3 years), who were part of a randomly selected sample who agreed to participate in the New South Wales Schools Fitness and Physical Activity Survey, 1997. Boys had higher levels of cardiorespiratory endurance and were more competent than girls on 5 out of 6 skills. Grade 10 students were better on all skills and were aerobically fitter than Grade 8 students. All six skills and a skills index were related to the number of laps completed on the MFT. The six skills explained 20% and 26% of the variance in the number of laps completed on the MFT for Grade 8 and Grade 10 girls, respectively, and 12% and 17% for Grade 8 and Grade 10 boys, respectively. This finding can be interpreted as evidence of a relationship between cardiorespiratory endurance and fundamental movement skills among adolescents. Further studies are recommended to determine if improved movement skills in adolescents can promote cardiorespiratory endurance.
Samuel W. Logan, E. Kipling Webster, Nancy Getchell, Karin A. Pfeiffer and Leah E. Robinson
The purpose of this review is to synthesize the evidence of the relationship between fundamental motor skills (FMS) competence and physical activity by qualitatively describing results from 13 studies that met rigorous inclusion criteria. Inclusion criteria: (a) published in a peer-review journal, (b) participants were between the ages of 3–18, (c) participants were typically developing, (d) FMS was measured by a process-oriented assessment, (e) assessed physical activity, (f) related FMS and physical activity through statistical procedures, and (g) printed in English. Databases were searched for relevant articles using key terms related to FMS and physical activity. Evidence suggested low to moderate relationships between FMS competence and physical activity in early childhood (r = .16 to .48; R 2 = 3–23%, 4 studies), low to high relationships in middle to late childhood (r = .24 to .55; R 2 = 6–30%, 7 studies), and low to moderate relationships in adolescence (r = .14 to .35; R 2 = 2–12.3%, 2 studies). Across ages, object control skills and locomotor skills were more strongly related to physical activity for boys and girls, respectively. Future research should emphasize experimental and longitudinal research designs to provide further understanding of the relationship between FMS competence and physical activity.
Andrew A. Dingley, David B. Pyne and Brendan Burkett
To characterize relationships between propulsion, anthropometry, and performance in Paralympic swimming.
A cross-sectional study of swimmers (13 male, 15 female) age 20.5 ± 4.4 y was conducted. Subject locomotor categorizations were no physical disability (n = 8, classes S13–S14) and low-severity (n = 11, classes S9–S10) or midseverity disability (n = 9, classes S6–S8). Full anthropometric profiles estimated muscle mass and body fat, a bilateral swim-bench ergometer quantified upper-body power production, and 100-m time trials quantified swimming performance.
Correlations between ergometer mean power and swimming performance increased with degree of physical disability (low-severity male r = .65, ±0.56, and female r = .68, ±0.64; midseverity, r = .87, ±0.41, and r = .79, ±0.75). The female midseverity group showed nearperfect (positive) relationships for taller swimmers’ (with a greater muscle mass and longer arm span) swimming faster, while for female no- and low-severity-disability groups, greater muscle mass was associated with slower velocity (r = .78, ±0.43, and r = .65, ±0.66). This was supported with lighter females (with less frontal surface area) in the low-severity group being faster (r = .94, ±0.24). In a gender contrast, low-severity males with less muscle mass (r = -.64, ±0.56), high skinfolds (r = .78, ±0.43), a longer arm span (r = .58, ±0.60) or smaller frontal surface area (r = -.93, ±0.19) were detrimental to swimming-velocity production.
Low-severity male and midseverity female Paralympic swimmers should be encouraged to develop muscle mass and upper-body power to enhance swimming performance. The generalized anthropometric measures appear to be a secondary consideration for coaches.