Ambulatory children and youth with cerebral palsy have limitations in locomotor capacities and in community mobility. The ability of three locomotor tests to predict community mobility in this population (N = 49, 27 boys, 6–16 years old) was examined. The tests were a level ground walking test, the 6-min-Walk-Test (6MWT), and two tests of advanced locomotor capacities, the 10-meter-Shuttle-Run-Test (10mSRT) and the Timed-Up-and-Down-Stairs-Test (TUDS). Community mobility was measured with the Assessment of Life Habits mobility category. After age and height were controlled, regression analysis identified 10mSRT and TUDS values as significant predictors of community mobility. They explained about 40% of the variance in the Life Habits mobility category scores. The 10mSRT was the strongest predictor (standardized Beta coefficient = 0.48, p = 0.002). The 6MWT was not a significant predictor. Thus, advanced locomotor capacity tests may be better predictors of community mobility in this population than level ground walking tests.
Chantale Ferland, Hélène Moffet and Désirée B. Maltais
The principles of direct dynamics and oscillating systems have been used to study the development of gait parameters in children, with respect to their kinetic consequences on the oscillations of body center of mass (CM). In particular the equations established (a) a natural body frequency (NBF), a body parameter specific to oscillating movements which is invariant for adults and decreases with age for children, and (b) the amplitude ratio of CM to center-of-foot pressure (CP) oscillations as a parametric function of the step frequency, whose parameter is the NBF. This function was used to analyze the development of gait locomotors with respect to their kinetic effects on balance in the frontal plane. Five children were examined longitudinally during their first 5 years of independent walking (IW), and two cross-sectional groups between 5 and 7 years of IW were also considered. The results showed a shift toward the low end of step frequency bands as the NBF decreased along with in variances in the amplitudes of CM oscillation in both the frontal and sagittal planes, regardless of age and gait velocity. The biomechanical meaning of the NBF, of its decrease and of postural invariances associated with the decrease of the frequency, are discussed as well how the programming of locomotor parameters adapts to changes in body structure during gait development.
Sofiya Alhassan, Ogechi Nwaokelemeh, Manneh Ghazarian, Jasmin Roberts, Albert Mendoza and Sanyog Shitole
This pilot study examined the effects of a teacher-taught, locomotor skill (LMS)- based physical activity (PA) program on the LMS and PA levels of minority preschooler-aged children. Eight low-socioeconomic status preschool classrooms were randomized into LMS-PA (LMS-oriented lesson plans) or control group (supervised free playtime). Interventions were delivered for 30 min/day, five days/week for six months. Changes in PA (accelerometer) and LMS variables were assessed with MANCOVA. LMS-PA group exhibited a significant reduction in during-preschool (F (1,16) = 6.34, p = .02, d = 0.02) and total daily (F (1,16) = 9.78, p = .01, d = 0.30) percent time spent in sedentary activity. LMS-PA group also exhibited significant improvement in leaping skills, F (1, 51) = 7.18, p = .01, d = 0.80). No other, significant changes were observed. The implementation of a teacher-taught, LMS-based PA program could potentially improve LMS and reduce sedentary time of minority preschoolers.
Isaac Estevan, Javier Molina-García, Ana Queralt, Octavio Álvarez, Isabel Castillo and Lisa Barnett
The Test of Gross Motor Development (TGMD) is a process-oriented scale that provides qualitative information on children’s motor competence. The aim of the current study was to analyze the psychometric properties by examining the internal consistency and construct validity of the Spanish version of the TGMD-3. A sample of 178 typically developing children (47.5% girls) between the ages 3 and 11 years participated in this study. Reliability and the within-network psychometric properties of TGMD-3 were examined by using internal consistency and confirmatory factor analysis. Reliability indexes were excellent (> 0.89). A two-factor structure model was hypothesized and an alternative unifactorial model was also tested. Adequate fit indexes in both a two-factor model [ball skills seven items and locomotor skills six items (χ2 (64) = 139.200, p < .010, RMSEA = 0.073, SRMR = 0.050, NNFI = 0.964, CFI = 0.970)] and a one-factor model [(χ2 (65) = 157.666, p < .010, RMSEA = 0.084, SRMR = 0.055, NNFI = 0.956, CFI = 0.963)] were found. The Spanish version of the TGMD-3 is thus suitable for studying children’s actual motor competence level in terms of locomotor and ball skills and also in terms of fundamental movement skills.
Mark L. Shik
Microstimulation of the brain stem was performed in the mesencephalic mudpuppy. Repetitive (8-15 pps) stimulation of the lateral mesencephalic tegmentum elicited cyclic side-to-side movements of the tail or the body and stepping of the hindlimbs or forelimbs in different combinations. The association of all four components was most common, followed by the combined movements of the tail and the body; the tail, the hindlimbs, and the body; and the tail and the hindlimbs. Movements of the tail and the hindlimbs also occurred separately, but lateral undulation of the body was observed only in combinations, as was mainly stepping of the forelimbs. The cycle durations varied in different patterns: In particular, a cycle lasted 5 to 7 s for tail movements and 1.3 to 2 s for complete locomotion. Usually only one pattern was evoked by stimulating a particular site in the brain stem, but sometimes increasing the strength or frequency of stimulation involved an additional elementary synergy, thus forming a more complex pattern. Similar patterns could arise from stimulation of different sites. The order of involvement of components in the same complex pattern varied when stimuli were applied to different sites. The combinatorial composition and morphological specification are possible mechanisms of the broad repertoire of elicited locomotor patterns in the mudpuppy.
Benjamin Pageaux, Jean Theurel and Romuald Lepers
knee extensors. 23 Our results demonstrate that completion of prolonged cycling and uphill walking exercises increases perception of effort during a subsequent running exercise. This higher perceived exertion is in accordance with previous studies demonstrating that locomotor muscle fatigue increases
Martin Gérin-Lajoie, Carol L. Richards and Bradford J. McFadyen
This article introduces a novel, ecological, obstructed walking paradigm. Gait adaptations to circumvent obstacles undergoing uncertain displacements, and the effect of revealing the obstacle’s action beforehand, were investigated in young adults. The personal space (PS) maintained during walking was quantified for the first time under different environmental factors including auditory distractions. Obstacle movement and its uncertainty resulted in gait adjustments aimed at gaining time to assess the situation. Early gait adaptations and constant clearances around the obstacle suggest that anticipation and preplanning are involved in such navigational tasks. Participants systematically maintained an elliptical PS during circumvention, but they adjusted its size according to different environmental factors. There was a relationship between the size of PS and level of attention, which suggests that the regulation of PS is used to control locomotion. This novel paradigm has important implications for the assessment and training of locomotor ability within real world environments.
Karin G.M. Gerritsen, Anton J. van den Bogert, Manuel Hulliger and Ronald F. Zernicke
The purpose of this study was to investigate, theoretically, to what extent muscle properties could contribute to recovery from perturbations during locomotion. Four models with different actuator properties were created: the FLVT model, which encompassed force-length (FL) and force-velocity (FV) characteristics of human muscles as well as muscle stimulation inputs as functions of time (T); the FLT model, which had muscles without force-velocity characteristics; the FVT model, which had muscles without specific force-length characteristics; and the MT model, which had no muscles but was driven by joint moments (M) as a function of time. Each model was exposed to static and dynamic perturbations and its response was examined. FLVT showed good resistance to both static and dynamic perturbations. FLT was resistant to static perturbation but could not counteract dynamic perturbation, whereas the opposite was found for FVT. MT could not counteract either of the perturbations. Based on the results of the simulations, skeletal muscle force-length-velocity properties, although interactively complex, contribute substantially to the dynamic stability of the musculoskeletal system.
Christopher McCrum, Katrin Eysel-Gosepath, Gaspar Epro, Kenneth Meijer, Hans H.C.M. Savelberg, Gert-Peter Brüggemann and Kiros Karamanidis
Posturography is used to assess balance in clinical settings, but its relationship to gait stability is unclear. We assessed if dynamic gait stability is associated with standing balance in 12 patients with unilateral vestibulopathy. Participants were unexpectedly tripped during treadmill walking and the change in the margin of stability (MoSchange) and base of support (BoSchange) relative to nonperturbed walking was calculated for the perturbed and first recovery steps. The center of pressure (COP) path during 30-s stance with eyes open and closed, and the distance between the most anterior point of the COP and the anterior BoS boundary during forward leaning (ADist), were assessed using a force plate. Pearson correlations were conducted between the static and dynamic variables. The perturbation caused a large decrease in the BoS, leading to a decrease in MoS. One of 12 correlations was significant (MoSchange at the perturbed step and ADist; r = −.595, P = .041; nonsignificant correlations: .068 ≤ P ≤ .995). The results suggest that different control mechanisms may be involved in stance and gait stability, as a consistent relationship was not found. Therefore, posturography may be of limited use in predicting stability in dynamic situations.
Lisa M. Barnett, Leah E. Robinson, E. Kipling Webster and Nicola D. Ridgers
The purpose was to determine the reliability of an instrument designed to assess young children’s perceived movement skill competence in 2 diverse samples.
A pictorial instrument assessed 12 perceived Fundamental Movement Skills (FMS) based on the Test of Gross Motor Development 2nd edition. Intra-Class Correlations (ICC) and internal consistency analyses were conducted. Paired sample t tests assessed change in mean perceived skill scores. Bivariate correlations between the intertrial difference and the mean of the trials explored proportional bias.
Sample 1 (S1) were culturally diverse Australian children (n = 111; 52% boys) aged 5 to 8 years (mean = 6.4, SD = 1.0) with educated parents. Sample 2 (S2) were racially diverse and socioeconomically disadvantaged American children (n = 110; 57% boys) aged 5 to 10 years (mean = 6.8, SD = 1.1). For all children, the internal consistency for 12 FMS was acceptable (S1 = 0.72, 0.75, S2 = 0.66, 0.67). ICCs were higher in S1 (0.73) than S2 (0.50). Mean changes between trials were small. There was little evidence of proportional bias.
Lower values in S2 may be due to differences in study demographic and execution. While the instrument demonstrated reliability/internal consistency, further work is recommended in diverse samples.