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Dual-task walking and cell phone usage, which is associated with high cognitive load and reduced situational awareness, can increase risk of a collision, a fall event, or death. The objective of this study was to quantify the effect of dual-task cell phone talking, texting, and reading while walking on spatiotemporal gait parameters; minimum foot clearance; and dynamic stability of the lower limb joints, trunk, and head. Nineteen healthy male participants walked on an instrumented treadmill at their self-selected speed as well as walking while simultaneously (1) reading on a cell phone, (2) texting, and (3) talking on a cell phone. Gait analyses were performed using an optical motion analysis system, and dynamic stability was calculated using the Maximum Lyapunov Exponent. Dual-task cell phone usage had a significant destabilizing influence on the lower limb joints during walking. Cell phone talking while walking significantly increased step width and length and decreased minimum foot clearance height (P < .05). The findings suggest that dual-task walking and cell phone conversation may present a greater risk of a fall event than texting or reading. This may be due to the requirements for more rapid information processing and cognitive demand at the expense of motor control of joint stability.

We previously showed that perceived effort during visually guided reaching was altered as task demand varied. Further, self-reported subjective fatigue correlated with perceived effort and reach performance under visually guided conditions. Memory-guided reaching often leads to performance deterioration and can provide insights about the planning and control of reach actions. It is unclear how perceived effort changes during memory-guided reaching and whether self-reported subjective fatigue is associated with perceived effort of memory-guided reaching. Twenty-three young adults performed reach actions under visually- and memory-guided conditions. Perceived effort, reaction time, and endpoint error increased significantly from the visually- to the memory-guided condition. Self-reported subjective fatigue was associated with perceived effort and reach distance error during memory-guided reaching; those with higher levels of fatigue reported greater perceived effort and tended to reach farther when visual information was not available. These findings establish a foundation to examine relationships between subjective fatigue, perceived effort, and reach control.

Load carriage experiments are typically performed from a linear perspective that assumes that movement variability is equivalent to error or noise in the neuromuscular system. A complimentary, nonlinear perspective that treats variability as the object of study has generated important results in movement science outside load carriage settings. To date, no systematic review has yet been conducted to understand how load carriage dynamics change from a nonlinear perspective. The goal of this systematic review is to fill that need. Relevant literature was extracted and reviewed for general trends involving nonlinear perspectives on load carriage. Nonlinear analyses that were used in the reviewed studies included sample, multiscale, and approximate entropy; the Lyapunov exponent; fractal analysis; and relative phase. In general, nonlinear tools successfully distinguish between unloaded and loaded conditions in standing and walking, although not in a consistent manner. The Lyapunov exponent and entropy were the most used nonlinear methods. Two noteworthy findings are that entropy in quiet standing studies tends to decrease, whereas the Lyapunov exponent in walking studies tends to increase, both due to added load. Thus, nonlinear analyses reveal altered load carriage dynamics, demonstrating promise in applying a nonlinear perspective to load carriage while also underscoring the need for more research.

Quality experiences in sport programming for children with autism spectrum disorder (ASD) can promote physical and psychosocial benefits and long-term quality participation (QP). Unfortunately, children with ASD often experience sport participation barriers and, consequently, participate less in sport compared with children without disabilities. This study investigated QP priorities and strategies that could foster QP for children with ASD. Caregivers (n = 13), volunteers (n = 26), and staff (n = 14) involved in sport programming for children with ASD rated experiential elements of QP using the Measure of Experiential Aspects of Participation. In addition , a two-round Delphi survey with staff (Round 1: n = 11; Round 2: n = 13) generated 22 strategies for promoting QP—each rated highly with regard to importance (5.69–6.85 on a 7-point scale). Strategies were substantiated with published research evidence. Findings informed the development of a QP tool designed to help instructors implement identified strategies in hopes of improving sport experiences for children with ASD.

Sport psychology scholars have long called for the field to take intersectional approaches to research and applied practice. Missing from this call is the study of intersectionality in the classroom. Therefore, the purpose of this practice paper is to provide a resource for sport psychology practitioners to take an intersectional approach in their teaching. First, the author provides a brief overview of intersectional theory and approaches to using anti-oppressive practices in the classroom. The author then reflects on their experience utilizing an intersectional lens as a neophyte instructor. Finally, the author discusses lessons learned from this teaching experience. This practice paper serves as a resource for sport psychology scholars and practitioners to integrate the study of intersectionality in their roles. While this paper is written for the higher education classroom, all readers will gain knowledge on intersectional theory and how it can be integrated in their scholarship or applied practice.

Altering running cadence is commonly done to reduce the risk of running-related injury/reinjury. This study examined how altering running cadence affects joint kinetic patterns and stride-to-stride kinetic variability in uninjured female runners. Twenty-four uninjured female recreational runners ran on an instrumented treadmill with their typical running cadence and with a running cadence that was 7.5% higher and 7.5% lower than typical. Ground reaction force and kinematic data were recorded during each condition, and principal component analysis was used to capture the primary sources of variability from the sagittal plane hip, knee, and ankle moment time series. Runners exhibited a reduction in the magnitude of their knee extension moments when they increased their cadence and an increase in their knee extension moments when they lowered their cadence compared with when they ran with their typical cadence. They also exhibited greater stride-to-stride variability in the magnitude of their hip flexion moments and knee extension moments when they deviated from their typical running cadence (ie, running with either a higher or lower cadence). These differences suggest that runners could alter their cadence throughout a run in an attempt to limit overly repetitive localized tissue stresses.

The purpose of study was to compare the kinematic patterns of the thoracic, lumbar, and pelvis segments and hip joints between 2 low back pain subgroups and healthy women during sit-to-stand and stand-to-sit. Kinematic data of 44 healthy women and 2 subgroups of females with low back pain in 2 subgroups of movement system impairment model (rotation-extension [Rot.Ext] and rotation-flexion [Rot.Flex]) were recorded. Participants performed sit-to-stand and stand-to-sit at a preferred speed. Each task was divided into a pre buttock lifted off/on (pre-BO_ff/n) phase and a post-BO_ff/n phase. The Rot.Ext subgroup showed greater range of motion in the thoracic during pre-BO_ff phase of sit-to-stand (P < .001) and pre-BO_n phase of stand-to-sit (P = .01) compared to the other 2 groups. The Rot.Flex subgroup displayed limited left hip joint excursion during sit-to-stand pre-BO_ff (P = .04) and stand-to-sit post-BO_n phases (P = .02). The Rot.Flex subgroup showed greater pelvis tilt excursion during sit-to-stand post-BO_ff (P = .04) and stand-to-sit pre-BO_n (P = .01) and post-BO_n phases (P = .01). In subgroups of women with chronic low back pain, there were kinematic changes in adjacent body segments/joints of lumbar spine during sit-to-stand and stand-to-sit tasks.