This study compared accelerometer-assessed habitual physical activity (PA), sedentary time, and meeting PA recommendations among 102 youth with disabilities (7–20 years) in four subgroups—physical/visual impairments, intellectual disability, autism spectrum disorders, and hearing impairment—and 800 youth with typical development (8–16 years). Low proportions of youth with disabilities met PA recommendations, and they generally were less physically active and more sedentary than youth with typical development. The hearing impairment and autism spectrum disorder groups were the most and least physically active, respectively. Older age and to some extent female sex were related to less PA and more sedentary time. Considering the suboptimal levels of PA in youth with disabilities, effective interventions directed at factors associated with PA among them are needed.
Karin Lobenius-Palmér, Birgitta Sjöqvist, Anita Hurtig-Wennlöf and Lars-Olov Lundqvist
Kelly P. Arbour-Nicitopoulos, Viviane Grassmann, Krystn Orr, Amy C. McPherson, Guy E. Faulkner and F. Virginia Wright
The objective of this study was to comprehensively evaluate inclusive out-of-school time physical activity programs for children/youth with physical disabilities. A search of the published literature was conducted and augmented by international expertise. A quality appraisal was conducted; only studies with quality ratings ≥60% informed our best practice recommendations. Seventeen studies were included using qualitative (n = 9), quantitative (n = 5), or mixed (n = 3) designs. Programs had a diversity of age groups, group sizes, and durations. Most programs were recreational level, involving both genders. Rehabilitation staff were the most common leaders. Outcomes focused on social skills/relationships, physical skill development, and psychological well-being, with overall positive effects shown in these areas. The best practice recommendations are consistent with an abilities-based approach emphasizing common group goals and interests; cooperative activities; mastery-oriented, individualized instruction; and developmentally appropriate, challenging activities. Results indicate that inclusive out-of-school time physical activity programs are important for positive psychosocial and physical skill development of children/youth with physical disabilities.
Tomomasa Nakamura, Yuriko Yoshida, Hiroshi Churei, Junya Aizawa, Kenji Hirohata, Takehiro Ohmi, Shunsuke Ohji, Toshiyuki Takahashi, Mitsuhiro Enomoto, Toshiaki Ueno and Kazuyoshi Yagishita
The aim of this study was to analyze the effect of teeth clenching on dynamic balance at jump landing. Twenty-five healthy subjects performed jump-landing tasks with or without teeth clenching. The first 3 trials were performed with no instruction; subsequently, subjects were ordered to clench at the time of landing in the following 3 trials. We collected the data of masseter muscle activity by electromyogram, the maximum vertical ground reaction force (vGRFmax) and center of pressure (CoP) parameters by force plate during jump-landing. According to the clenching status of control jump-landing, all participants were categorized into a spontaneous clenching group and no clenching group, and the CoP data were compared. The masseter muscle activity was correlated with vGRFmax during anterior jump-landing, while it was not correlated with CoP. In comparisons between the spontaneous clenching and the no clenching group during anterior jump-landing, the spontaneous clenching group showed harder landing and the CoP area became larger than the no clenching group. There were no significant differences between pre- and postintervention in both spontaneous clenching and no clenching groups. The effect of teeth clenching on dynamic balance during jump-landing was limited.
Matthew C. Hoch, David R. Mullineaux, Kyoungkyu Jeon and Patrick O. McKeon
Single joint kinematic alterations have been identified during gait in those with chronic ankle instability (CAI). The purpose of this study was to compare sagittal plane hip, knee, and ankle kinematics during walking in participants with and without CAI. Twelve individuals with CAI and 12 healthy individuals walked on a treadmill at 1.5 m/s. Three-dimensional kinematics were analyzed using mean ensemble curves and independent t tests. Participants with CAI demonstrated less lower extremity flexion during the absorption phase of stance and the limb placement phase of swing, which may have implications for limb placement at initial contact.
Bente R. Jensen, Line Hovgaard-Hansen and Katrine L. Cappelen
Running on a lower-body positive-pressure (LBPP) treadmill allows effects of weight support on leg muscle activation to be assessed systematically, and has the potential to facilitate rehabilitation and prevent overloading. The aim was to study the effect of running with weight support on leg muscle activation and to estimate relative knee and ankle joint forces. Runners performed 6-min running sessions at 2.22 m/s and 3.33 m/s, at 100%, 80%, 60%, 40%, and 20% body weight (BW). Surface electromyography, ground reaction force, and running characteristics were measured. Relative knee and ankle joint forces were estimated. Leg muscles responded differently to unweighting during running, reflecting different relative contribution to propulsion and antigravity forces. At 20% BW, knee extensor EMGpeak decreased to 22% at 2.22 m/s and 28% at 3.33 m/s of 100% BW values. Plantar flexors decreased to 52% and 58% at 20% BW, while activity of biceps femoris muscle remained unchanged. Unweighting with LBPP reduced estimated joint force significantly although less than proportional to the degree of weight support (ankle).It was concluded that leg muscle activation adapted to the new biomechanical environment, and the effect of unweighting on estimated knee force was more pronounced than on ankle force.
Jennifer M. Medina McKeon, Patrick O. McKeon and Marjorie A. King
Kristen Couper Schellhase, Jennifer L. Plant and Carey E. Rothschild
Nathan Millikan, Dustin R. Grooms, Brett Hoffman and Janet E. Simon
Context: Functional tests are limited primarily by measuring only physical performance. However, athletes often multitask, and deal with complex visual-spatial processing while being engaged in physical activity. Objective: To present the development and reliability of 4 new neurocognitive single-leg hop tests that provide more ecological validity to test sport activity demands than previous functional return to sport testing. Design: Cross-sectional. Setting: Gymnasium. Participants: Twenty-two healthy participants (9 males and 13 females; 20.9 [2.5] y, 171.2 [11.7] cm, 70.3 [11.0] kg) were recruited. Interventions: Maximum distance (physical performance) and reaction time (cognitive performance) were measured for 3 of the neurocognitive hop tests all testing a different aspect of neurocognition (single-leg central-reaction hop—reaction time to 1 central stimulus, single-leg peripheral-reaction crossover hop—reaction time between 2 peripheral stimuli, and single-leg memory triple hop—reaction to memorized stimulus with distractor stimuli). Fastest time (physical performance) and reaction time (cognitive performance) were measured for the fourth neurocognitive hop test (single-leg pursuit 6m hop—requiring visual field tracking [pursuit] and spatial navigation). Main Outcome Measures: Intraclass correlation coefficients were calculated to assess reliability of the 4 new hop tests. Additionally, Bland–Altman plots and 1-sample t tests were conducted for each single-leg neurocognitive hop to evaluate any systematic changes. Results: Intraclass correlation coefficients based on day 1 and day 2 scores ranged from .87 to .98 for both legs for physical and cognitive performance. The Bland–Altman plots and 1-sample t tests (P > .05) indicated that all 4 single-leg neurocognitive hop tests did not change systematically. Conclusions: These data provide evidence that a neurocognitive component can be added to the traditional single-leg hop tests to provide a more ecologically valid test that incorporates the integration of physical and cognitive function for return to sport. The test–retest reliability of the 4 new neurocognitive hop tests is highly reliable and does not change systematically.
Kayla E. Boehm and Kevin C. Miller
Clinical Scenario: Exertional heat stroke (EHS) is a medical emergency characterized by body core temperatures >40.5°C and central nervous system dysfunction. An EHS diagnosis should be immediately followed by cold-water immersion (CWI). Ideally, EHS victims cool at a rate >0.15°C/min until their temperature reaches 38.9°C. While generally accepted, these EHS treatment recommendations often stem from research that examined only males. Since gender differences exist in anthropomorphics (eg, body surface area, lean body mass) and anthropomorphics impact CWI cooling rates, it is possible that CWI cooling rates may differ between genders. Clinical Question: Do CWI rectal temperature (T rec) cooling rates differ between hyperthermic males and females? Summary of Findings: The average T rec cooling rate across all examined studies for males and females was 0.18 (0.05) and 0.24 (0.03)°C/min, respectively. Hyperthermic females cooled ∼33% faster than males. Clinical Bottom Line: Hyperthermic females cooled faster than males, most likely because of higher body surface area to mass ratios and less lean body mass. Regardless of gender, CWI is highly effective at lowering T rec. Clinicians must be able to treat all EHS victims, regardless of gender, with CWI, given its high survival rate when implemented appropriately. Strength of Recommendation: Moderate evidence (2 level 3 studies) suggests that females cool faster than males when treated with CWI following severe hyperthermia. Despite gender differences, cooling rates exceeded cooling rate recommendations for EHS victims (ie, 0.15°C/min).
Timothy M. Wohlfert and Kevin C. Miller
Clinical Scenario: Exertional heat stroke (EHS) is a potentially deadly heat illness and poses a significant health risk to athletes; EHS survival rates are near 100% if properly recognized and treated. Whole-body cold water immersion (CWI) is the most effective method for lowering body core temperature. Precooling (PC) with CWI before exercise may prevent severe hyperthermia or EHS by increasing the body’s overall heat storage capacity. However, PC may also alter athletes’ perception of how hot they feel or how hard they are exercising. Consequently, they may be unable to accurately perceive their body core temperature or how hard they are working, which may predispose them to severe hyperthermia or EHS. Clinical Question: Does PC with whole-body CWI affect thermal sensation (TS) or rating of perceived exertion (RPE) during exercise in the heat? Summary of Key Findings: In 4 studies, RPE during exercise ranged from 12 (2.0) to 20 (3.0), with no clinically meaningful differences between PC and control trials. TS scores ranged from 2 (1.0) to 8 (0.5) in control trials and from 2 (1.0) to 7.5 (0.5) during PC trials. Clinical Bottom Line: PC did not cause clinically meaningful differences in RPE or TS during exercise. It is unlikely that PC would predispose athletes to EHS by altering perceptions of exercise intensity or body core temperature. Strength of Recommendation: None of the reviewed studies (all level-2 studies with Physiotherapy Evidence Database scores ≥ 5) suggest that PC with CWI influences RPE or TS in exercising males.