Search Results

Motor competence is associated with psychological and physical health outcomes. A reciprocal relationship between motor competence and perceptions of physical competence exists, but the developmental trajectory of the motor competence/perceived competence relationship is not well understood. Standardized assessments take a product- or process-oriented approach, but research concerning the motor competence/perceived competence relationship is limited to using process-oriented assessments. It is unknown whether boys and girls use product and process information differentially in the development of perceived competence. Children (N = 411) were aggregated into age groups. Perceived competence and product and process aspects of motor competence were assessed. Older children were more skillful than younger children but reported lower perceived competence. The motor competence/perceived competence association increased for both motor competence measures across age groups. Girls demonstrated stronger associations between process measures of motor competence and perceived competence, while boys indicated stronger associations between product measures of motor competence and perceived competence. When both motor competence measures were used to predict perceived competence, more variance in perceived competence was explained, compared with using independent predictors. The strength of the prediction increased across age groups, indicating that motor competence is a stronger predictor of perceived competence in older children.

Context: A variety of gait retraining interventions are available to modify running mechanics associated with musculoskeletal injuries. These often require specialized equipment and/or personnel to prompt the runner toward specific strategies. Objective: To determine whether instructing female recreational runners to “run quietly” could decrease impact force characteristics. Design: Cohort. Setting: Research laboratory. Participants: Fifteen healthy female recreational runners (24 [7] y) volunteered. Interventions: Baseline testing occurred on day 1 (baseline), a posttraining assessment occurred on day 2 (training), and a final assessment occurred 1 week after training on day 3 (follow-up). A smartphone decibel measuring app was used to provide biofeedback on the decibel level of foot strike on day 2 (training). Main Outcomes: Peak vertical force, impact transient, peak and average vertical loading rate, ground contact time, and running economy were collected on each day and compared via repeated-measures analyses of variance. Results: Vertical ground reaction force was lower at follow-up (2.30 bodyweights [BW]) versus baseline (2.39 BW, P = .023) and training (2.34 BW, P = .047). Maximal loading rate decreased from baseline (69.70 BW·s⁻¹) to training (62.24 BW·s⁻¹, P = .021) and follow-up (60.35 BW·s⁻¹, P = .031). There was no change in running economy. Conclusions: Our findings demonstrate that simple instructions to “run quietly” can yield immediate and sustained reductions in impact force profiles, which do not influence running economy.

Context: Previous work has demonstrated an improvement in running economy during sustained running on a lower body positive pressure treadmill, but neuromuscular and spatiotemporal measures have only been investigated during short-duration running bouts on these devices. The current study sought to replicate the noted metabolic response and investigate whether neuromuscular and/or spatiotemporal adaptations underlie the noted improvements in running economy. Design: Cross-sectional. Methods: Fifteen trained runners (11 males and 4 females) ran three 15-minute trials with 30% bodyweight support at 70% of the speed that elicited their peak oxygen consumption while running on a standard treadmill. A series of 1-way analyses of variance with repeated measures were used to explore differences in dependent variables over the 45 minutes of running. Dependent variables included oxygen consumption, root-mean-square electromyography of the vastus medialis and medial gastrocnemius during stance, and spatiotemporal parameters. Results: Oxygen consumption decreased after the initial exposure, with no further reductions after 20 minutes. Root-mean-square electromyography of the vastus medialis and medial gastrocnemius also decreased over time, with no further reductions after 20 and 10 minutes, respectively. No differences in spatiotemporal parameters were found. Conclusions: Future research should provide sufficient time for runners to develop a more economical gait pattern prior to collecting dependent variables, and previous findings using lower body positive pressure treadmills may need to be reconsidered. Athletes using these devices for training or rehabilitation should note that increased economy will lower the intensity of a given treadmill setting over time.