Effects of releasing ankle joint during electrically evoked cycling in persons with motor complete spinal cord injury.

Literature has shown that simulated power production during conventional functional electrical stimulation (FES) cycling was improved by 14% by releasing the ankle joint from a fixed ankle setup and with the stimulation of the tibialis anterior and triceps surae. This study aims to investigate the effect of releasing the ankle joint on the pedal power production during FES cycling in persons with spinal cord injury (SCI). Seven persons with motor complete SCI participated in this study. All participants performed 1 min of fixed-ankle and 1 min of free-ankle FES cycling with two stimulation modes. In mode 1 participants performed FES-evoked cycling with the stimulation of quadriceps and hamstring muscles only (QH stimulation), while Mode 2 had stimulation of quadriceps, hamstring, tibialis anterior, and triceps surae muscles (QHT stimulation). The order of each trial was randomized in each participant. Free-ankle FES cycling offered greater ankle plantar- and dorsiflexion movement at specific slices of 20° crank angle intervals compared to fixed-ankle. There were significant differences in the mean and peak normalized pedal power outputs (POs) [F(1,500) = 14.03, p < 0.01 and F(1,500) = 7.111, p = 0.008, respectively] between fixed- and free-ankle QH stimulation, and fixed- and free-ankle QHT stimulation. Fixed-ankle QHT stimulation elevated the peak normalized pedal PO by 14.5% more than free-ankle QH stimulation. Releasing the ankle joint while providing no stimulation to the triceps surae and tibialis anterior reduces power output. The findings of this study suggest that QHT stimulation is necessary during free-ankle FES cycling to maintain power production as fixed-ankle.

Moderate-to-vigorous intensity physical activity levels of children with intellectual disability during physical education classes.

Background: Physical education (PE) class is an excellent way to improve moderate-to-vigorous intensity physical activity (MVPA). Increasing number of research has explored the children's PA based on movement during PE classes, but data for children with intellectual disability (ID) is still lacking. Purpose: The purpose of this study was to investigate the current status of MVPA levels of children with ID during PE classes in China, as well as differences of MVPA levels according to gender and grade. Methods: Accelerometers were used to record MVPA levels of fifty-three children with severe ID from 9 to 16 years of age (mean age: 12.60 ± 1.66 years) during standard PE classes. Results: The mean time spent in MVPA during PE classes was 8.00 ± 2.10 min, meaning only 22.88% of PE class time was spent in MVPA. As grade levels progresses, time spent in MVPA during PE classes tended to decrease; the fourth-grade children tended to spend more time in MVPA during PE classes compared with the fifth-grade and the sixth-grade (9.15 vs. 7.61 vs. 7.25 min, all p < 0.05). Boys spend significantly more time in MVPA during PE classes than girls; both in the entire sample (9.20 vs. 5.70 min) as well as in each grade (9.76 vs. 6.09 min, 9.35 vs. 5.68 min, 8.31 vs. 5.59 min, all p < 0.05). Conclusion: Findings from this study indicate that the proportion of PE class spent in the MVPA of children with ID was lower than the 50% recommended by the U.S. Department of Health and Human Services (DHHS) and U.K. Association for Physical Education (AfPE). And the amount of MVPA participation varied by the grade and gender as well as by the activity performed. Therefore, in order to help children with ID achieve MVPA goals, educators need to reevaluate the PE curriculum as well as take due consideration of grade and gender when devising new content.

Test-retest reliability of the single leg stance on a Lafayette stability platform.

The validity and reliability of the Lafayette stability platform are well-established for double leg testing. However, no evaluation of single leg (SL) stance on the platform was discovered yet. Therefore, this study aimed to investigate the reliability of conducting the SL stance on the Lafayette platform. Thirty-six healthy and active university students (age 23.2 ± 3.2 years; BMI 21.1 ± 3.1 kg/m2) were tested twice, one week apart (week 1; W1, week 2; W2). They stood on their dominant leg with eyes-open (EO) and eyes-closed (EC) in random order. Three successful trials of 20 seconds each were recorded. The duration during which the platform was maintained within 0° of tilt was referred to as time in balance (TIB). At all-time points, TIB was consistently longer in EO (EOW1: 17.02 ± 1.04s; EOW2: 17.32 ± 1.03s) compared to EC (ECW1: 11.55 ± 1.73s; ECW2: 13.08 ± 1.82s). A ±10 seconds difference was demonstrated in the Bland-Altman analysis in both EO and EC. Lower standard error of measurement (SEM) and coefficient of variation (CV) indicated consistent output. High intraclass correlation coefficient (ICC) values were seen between weeks (EO = 0.74; EC = 0.76) and within weeks (EOW1 = 0.79; EOW2 = 0.86; ECW1 = 0.71; ECW2 = 0.71). Although statistical measures (i.e., SEM, CV, and ICC) indicated good reliability of Lafayette for SL tasks, the wide agreement interval is yet to be clinically meaningful. Factors underlying the wide variation need to be identified before Lafayette is used for TIB assessment.

The effect of high and low velocity-based training on the throwing performance of collegiate handball players.

Background: The intensity of strength training exercise is generally regarded to be the most essential element in developing muscle strength and power. The exercise intensity of strength training is known as one-repetition maximum (1RM). Velocity-based training (VBT) has been proposed as a different approach for determining training intensity. VBT relies on the use of linear position transducers and inertial measurement units, providing real-time feedback to objectively adjust the exercise intensity based on an athlete's velocity zone. Methods: This study investigated the effects of two different training interventions based on individualized load velocity profiles (LVP) on maximal bench press strength (i.e., 1RM), maximum throwing velocity (TV), and skeletal muscle mass (SKMM). Twenty-two university handball players were randomly assigned to Group 1 (low-movement speed training) or Group 2 (high-movement speed training). Group 1 exercised with a bar speed of 0.75-0.96 m/s, which corresponds to a resistance of approximately 60% 1RM, whereas Group 2 trained at 1.03-1.20 m/s, corresponding to a resistance of approximately 40% 1RM. Both groups exercised three times a week for five weeks, with strength and throwing tests performed at baseline and post-intervention. Results: A two-way repeated measures ANOVA was applied, and the results showed the interaction between group and time was not statistically significant for SKMM (p = 0.537), 1RM (p = 0.883), or TV (p = 0.774). However, both groups significantly improved after the five weeks of training: SKMM (3.1% and 3.5%, p < 0.01), 1RM (15.5% and 15.0%, p < 0.01), and throwing velocity (18.7% and 18.3%, p < 0.01) in Group 1 and 2 respectively. Training at both prescribed velocities in this study elicited similar changes in strength, muscle mass, and throwing velocity.

Family factors associated with physical activity in children with intellectual disability: A systematic review.

This systematic review aimed to explore the influence of family factors on physical activity in children with intellectual disability. How and what family factors that specifically influence physical activity has not been compiled and reviewed previously. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic search was performed for articles published in English and Chinese without any year limits in six databases. Ten studies met the eligibility criteria and were included in the review. All studies were qualitatively integrated to identify and compare positive and negative family factors. A total of 1135 participants, of which 497 were children with intellectual disability while the other 638 participants were family members (parents, siblings and caregivers). The family factors of 6 themes and 18 sub-themes (10 positive, 7 negative and 1 inconclusive factors) were extracted. Overall, these results highlight the importance of encouragement, support and involvement by family members, concurrently it points out that parental psychological factors, socioeconomic status, responsibilities and electronic devices could both promote and hinder engagement in physical activity for children with intellectual disability. The findings accentuate the role of the family unit in helping determine the activity levels of children with intellectual disability. Future studies should include a wider range of participants and be longitudinal in nature, utilizing more accurate monitoring tools.

Pressure Sensor System for Customized Scoliosis Braces.

Hard-shell thoracolumbar sacral orthoses (TLSOs) are used for treating idiopathic scoliosis, a deformation of the spine with a sideways curvature. The pressure required inside the TLSO for ideal corrective results remains unclear. Retrofitting TLSOs with commercially available pressure measurement systems is expensive and can only be performed in a laboratory. The aim of this study was to develop a cost-effective but accurate pressure sensor system for TLSOs. The sensor was built from a piezoresistive polymer, placed between two closed-cell foam liners, and evaluated with a material testing machine. Because foams are energy absorbers, the pressure-conductance curve was affected by hysteresis. The sensor was calibrated on a force plate with the transitions from loading to unloading used to establish the calibration curve. The root mean square error was 12% on average within the required pressure range of 0.01-0.13 MPa. The sensor reacted to the changing pressure during breathing and different activities when tested underneath a chest belt at different tensions. The peak pressure reached 0.135 MPa. The sensor was further tested inside the scoliosis brace during different activities. The measured pressure was 0.014-0.124 MPa. The results from this study enable cheaper and mobile systems to be used for clinical studies on the comfort and pressure of braces during daily activities.

Investigating the Contextual Interference Effect Using Combination Sports Skills in Open and Closed Skill Environments.

This study attempted to present conditions that were closer to the real-world setting of team sports. The primary purpose was to examine the effects of blocked, random and game-based training practice schedules on the learning of the field hockey trap, close dribble and push pass that were practiced in combination. The secondary purpose was to investigate the effects of predictability of the environment on the learning of field hockey sport skills according to different practice schedules. A game-based training protocol represented a form of random practice in an unstable environment and was compared against a blocked and a traditional random practice schedule. In general, all groups improved dribble and push accuracy performance during the acquisition phase when assessed in a closed environment. In the retention phase, there were no differences between the three groups. When assessed in an open skills environment, all groups improved their percentage of successful executions for trapping and passing execution, and improved total number of attempts and total number of successful executions for both dribbling and shooting execution. Between-group differences were detected for dribbling execution with the game-based group scoring a higher number of dribbling successes. The CI effect did not emerge when practicing and assessing multiple sport skills in a closed skill environment, even when the skills were practiced in combination. However, when skill assessment was conducted in a real-world situation, there appeared to be some support for the CI effect. Key pointsThe contextual interference effect was not supported when practicing several skills in combination when the sports skills were assessed in a closed skill environment.There appeared to be some support for the contextual interference effect when sports skills were assessed in an open skill environment, which were similar to a real game situation.A game-based training schedule can be used as an alternative practice schedule as it displayed superior learning compared to a blocked practice schedule when assessed by the game performance test (real-world setting). The game-based training schedule also matched the blocked and random practice schedules in the other tests.

Spotlight on Athletes With a Disability: Malaysian Newspaper Coverage of the 2012 London Paralympic Games.

This study analyzed newspaper coverage of the 2012 London Paralympic Games by 8 Malaysian newspapers. Articles and photographs from 4 English-language and 4 Malay-language newspapers were examined from August 28 (1 day before the Games) to September 10, 2012 (1 day after the Games closing). Tables, graphs, letters, fact boxes, and lists of events were excluded from analysis. A total of 132 articles and 131 photographs were analyzed. Content analysis of the newspaper articles revealed that most (62.8%) of the articles contained positive reference to the athletes with a disability. There were equal numbers (39.1%) of action and static shots of athletes. More articles and photographs of Malaysian (58%) than non-Malaysian (42%) athletes with a disability were identified. Only 14.9% of the articles and photographs were related to female athletes with a disability.

Practicing field hockey skills along the contextual interference continuum: a comparison of five practice schedules.

To overcome the weakness of the contextual interference (CI) effect within applied settings, Brady, 2008 recommended that the amount of interference be manipulated. This study investigated the effect of five practice schedules on the learning of three field hockey skills. Fifty-five pre-university students performed a total of 90 trials for each skill under blocked, mixed or random practice orders. Results showed a significant time effect with all five practice conditions leading to improvements in acquisition and learning of the skills. No significant differences were found between the groups. The findings of the present study did not support the CI effect and suggest that either blocked, mixed, or random practice schedules can be used effectively when structuring practice for beginners. Key pointsThe contextual interference effect did not surface when using sport skills.There appears to be no difference between blocked and random practice schedules in the learning of field hockey skills.Low (blocked), moderate (mixed) or high (random) interference practice schedules can be used effectively when conducting a multiple skill practice session for beginners.