399 research outputs found

    Practice-based skill acquisition of pushrim-activated power-assisted wheelchair propulsion versus regular handrim propulsion in novices

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    BACKGROUND: Regular handrim wheelchair (RHW) propulsion is straining for the upper extremities and wheelchair users often experience overuse problems. A recent advancement in wheelchair technology that could assist users is the pushrim-activated power-assisted wheelchair (PAPAW). PAPAWs are challenging to control, yet it is unclear how people learn to use a PAPAW. The purpose of this study is to examine early skill acquisition through practice in PAPAWs and compare it with RHWs. METHODS: Twenty-four able-bodied novices were randomly allocated to either the RHW group or the PAPAW group. The experiment consisted of five sessions with three blocks of 4 min steady-state practice at 1.11 m/s and 0.21 W/kg. Finally, a transfer to the other mode was made. Data were collected with a drag-test, breath-by-breath spirometry, and a motion capture system. The last minute of each four-minute block was used for analysis. A mixed analysis of variance (ANOVA) was used to test for group, time, and interaction effects. RESULTS: Both groups improved their (assisted) mechanical efficiency, reduced their stroke rate, right-left and forward-backward deviation on the treadmill, and had a lower rate of perceived exertion (RPE) over time. (Assisted) mechanical efficiency was higher for the PAPAW group than for the RHW group and RPE was lower. However, left-right and forward-backward deviation was also found to be higher in the PAPAW group. CONCLUSIONS: At the group level the energetic cost of RHW and PAPAW propulsion can be lowered through low-intensity practice in novice users. The PAPAW is more 'efficient' than the RHW given the reduced energy requirement of the user from the motor assist, but more difficult to control. Future studies on PAPAWs should focus on the control needs of the user and their interaction with the power-assist technology

    Learning of Wheelchair Racing Propulsion Skills Over Three Weeks of Wheeling Practice on an Instrumented Ergometer in Able-Bodied Novices

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    The acquisition of daily handrim wheelchair propulsion skill as a multi-layered phenomenon has been studied in the past. Wheelchair racing, however, is considerably different from daily handrim wheelchair propulsion in terms of propulsion technique, as well as the underlying equipment and interface. Understanding wheelchair racing skill acquisition is important from a general motor learning and skill acquisition perspective, but also from a performance and injury prevention perspective. The aim of the current lab-based study was 2-fold: to investigate the evolution of racing wheelchair propulsion skill among a sample of novices and to compare them with an experienced wheelchair racer under similar conditions. A convenience sample of 15 able-bodied novices (8 male, 7 female) completed a standardized three-week submaximal uninstructed practice protocol (3 weeks, 3 sessions per week, 3x4 min per session) in a racing wheelchair on an ergometer. Required wheeling velocity was set at 2.78 m/s (10 km/h) and a rolling friction coefficient of 0.011 (resulting in a mean target load of 21W) was used. For comparison, an experienced T54 Paralympic athlete completed one block of the same protocol. Kinetics, kinematics, and physiological data were captured. A mixed effects regression analysis was used to examine the effect of practice for the novices, while controlling for speed. All participants finished the protocol successfully. However, not all participants were able to achieve the target speed during the first few sessions. Statistically significant improvements over time were found for all outcome measures (i.e., lower metabolic strain, longer push and cycle times) with the exception of mean power and torque per push. The athlete used a significantly greater contact angle and showed “better” outcomes on most metabolic and kinetic variables. While the athlete used a semi-circular propulsion technique, most participants used a double looping over technique. Three weeks of uninstructed wheelchair racing practice significantly improved efficiency and skill among a group of novices, in line with previous studies on daily handrim wheelchair propulsion. The comparison with an experienced athlete expectedly showed that there is still a large performance (and knowledge) gap to be conquered

    Learning of Wheelchair Racing Propulsion Skills Over Three Weeks of Wheeling Practice on an Instrumented Ergometer in Able-Bodied Novices

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    The acquisition of daily handrim wheelchair propulsion skill as a multi-layered phenomenon has been studied in the past. Wheelchair racing, however, is considerably different from daily handrim wheelchair propulsion in terms of propulsion technique, as well as the underlying equipment and interface. Understanding wheelchair racing skill acquisition is important from a general motor learning and skill acquisition perspective, but also from a performance and injury prevention perspective. The aim of the current lab-based study was 2-fold: to investigate the evolution of racing wheelchair propulsion skill among a sample of novices and to compare them with an experienced wheelchair racer under similar conditions. A convenience sample of 15 able-bodied novices (8 male, 7 female) completed a standardized three-week submaximal uninstructed practice protocol (3 weeks, 3 sessions per week, 3x4 min per session) in a racing wheelchair on an ergometer. Required wheeling velocity was set at 2.78 m/s (10 km/h) and a rolling friction coefficient of 0.011 (resulting in a mean target load of 21W) was used. For comparison, an experienced T54 Paralympic athlete completed one block of the same protocol. Kinetics, kinematics, and physiological data were captured. A mixed effects regression analysis was used to examine the effect of practice for the novices, while controlling for speed. All participants finished the protocol successfully. However, not all participants were able to achieve the target speed during the first few sessions. Statistically significant improvements over time were found for all outcome measures (i.e., lower metabolic strain, longer push and cycle times) with the exception of mean power and torque per push. The athlete used a significantly greater contact angle and showed “better” outcomes on most metabolic and kinetic variables. While the athlete used a semi-circular propulsion technique, most participants used a double looping over technique. Three weeks of uninstructed wheelchair racing practice significantly improved efficiency and skill among a group of novices, in line with previous studies on daily handrim wheelchair propulsion. The comparison with an experienced athlete expectedly showed that there is still a large performance (and knowledge) gap to be conquered

    Development of a new scale for perceived self-efficacy in manual wheeled mobility:a pilot study

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    Objective: To study the psychometric qualities of a perceived self-efficacy in wheeled mobility scale. Design: Questionnaires. Subjects: Forty-seven wheelchair users with spinal cord injury (elite athletes n= 25, recreational n= 22, from 6 different countries). Method: Based on the literature, and expert's and wheelchair user's comments, a new Self-Efficacy in Wheeled Mobility Scale (SEWM(1)) was developed. Internal consistency (split-half and Cronbach's alpha) and concurrent validity (correlating the Self-Efficacy in Wheeled Mobility Scale with the Generalized Perceived Self-efficacy Scale (GSE) and the spinal cord injury Exercise Self-Efficacy Scale (ESES)) were assessed. To evaluate the construct validity, age, lesion level and completeness and time since injury between groups of participants and their total scores were compared statistically. Results: Cronbach's alpha for the SEWM was 0.91, internal consistency was r=0.90. Significant correlations between pairs of scales of the entire sample (SEWM-ESES: 0.60; SEWM-GSE: 0.50 (p <0.05; n=47, 2-tailed) and of the subgroup comparison (SEWM-ESES recreational r= 0.61; elite r=0.73), demonstrated fair construct and concurrent validity of the SEWM. Conclusion: The SEWM was found to be reliable and valid in active spinal cord injury. A larger more diverse sample is needed to support the psychometric qualities of the SEWM scale

    Effects of offloading devices on static and dynamic balance in patients with diabetic peripheral neuropathy:A systematic review

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    Patients with diabetic peripheral neuropathy (DPN) usually have reduced somatosensory information and altered perception in feet and ankles. Somatosensory information acts as feedback for movement control and loss of somatosensation leads to altered plantar pressure patterns during gait and stance. Offloading devices are used to reduce peak plantar pressure and prevent diabetic foot ulcers. However, offloading devices can unfortunately have negative effects on static and dynamic balance. It is important to investigate these unwanted effects, since patient with DPN already are at high risk of falling and offloading devices could potentially increase this risk. The aim of this systematic review is to investigate the effects of plantar offloading devices used for ulcer prevention on their role in static and dynamic balance control in patients with DPN. PubMed and Embase were systematically searched using relevant search terms. After title selection, abstract selection, and full-text selection only five articles could be included for further analysis. Two articles included static balance measurements, two articles included dynamic balance measurements, and one article included both. Results suggested that static balance control is reduced when rocker bottom shoes and different insole configurations are used, however, toe-only rockers showed less evidence for reduced static balance control. There was no evidence for reduced dynamic balance control in combination with offloading devices. However, these results should be interpreted with care, since the number of studies was very small and the quality of the studies was moderate. Future research should evaluate balance in combination with different offloading devices, so that clinicians subscribing them are more aware of their potential unwanted consequences

    Effects of 7-week Resistance Training on Handcycle Performance in Able-bodied Males

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    The effect of an upper body resistance training program on maximal and submaximal handcycling performance in able-bodied males was explored. Eighteen able-bodied men were randomly assigned to a training group (TG: n=10) and a control group (CG: n=8). TG received 7 weeks of upper body resistance training (60% of 1 repetition maximum (1RM), 3×10 repetitions, 6 exercise stations, 2 times per week). CG received no training. Peak values for oxygen uptake (V˙O2peak), power output (POpeak), heart rate (HRpeak), minute ventilation (V˙OEpeak) and respiratory exchange ratio (RERpeak), submaximal values (HR, V˙O2, RER, PO, and gross mechanical efficiency (GE)), and time to exhaustion (TTE) were determined in an incremental test pre- and post-training. Maximal isokinetic arm strength and 1RM tests were conducted. Ratings of perceived exertion (RPE) were assessed. A two-way repeated measures ANOVA and post-hoc comparisons were performed to examine the effect of time, group and its interaction (p&lt;0.05). TG improved on POpeak (8.55%), TTE (10.73%), and 1RM (12.28-38.98%). RPE at the same stage during pre- and post-test was lower during the post-test (8.17%). Despite no improvements in V˙O2peak, training improved POpeak, muscular strength, and TTE. Upper body resistance training has the potential to improve handcycling performance.</p

    A portable isometric knee extensor strength testing device:test-retest reliability and minimal detectable change scores of the Q-Force II in healthy adults

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    Abstract Background Although knee extensors are essential in daily activities (e.g. walking, climbing stairs), knee extensor strength is often not measured in clinical settings. Existing devices to test muscle strength are not always suitable to accurately measure the high forces of this muscle group. Therefore, a device to test muscle strength that is convenient, feasible, reliable, and valid in clinical settings is required. This study evaluated the reliability, responsiveness, and level of discomfort of the newly developed Q-Force ӀӀ (i.e. a portable device to measure isometric knee extensor strength) in healthy middle-aged and elderly adults. Methods Participants (n = 22) conducted two standardized test sessions on the Q-Force ӀӀ (five to ten days apart). Each session consisted of one familiarisation trial followed by three trials of peak isometric knee extension per each leg. Per trial, peak and mean knee extension force (N) and torque (Nm) were measured at 90° flexion. The level of discomfort was determined using a visual analog scale (VAS: 0-100). Intra Class Correlation (ICC, model: two-way mixed with absolute agreement), Standard Error of Measurement (SEM), and minimal detectable change (MDC) were determined. A repeated measures ANOVA was used to determine between-test variation. Results Excellent test-retest (ICC > 0.95) and inter-trial (ICC > 0.91) reliability for both legs were shown. No significant differences were found in peak and mean knee forces and torques between test and retest of both legs, indicating good test-retest reliability (P-value range: 0.360-0.538; F(1,21) range: 0.4-0.9). The SEM of the peak and mean forces and torques ranged from 28.0 to 30.4 N (6.0-6.8%) and from 9.2 to 10.4 Nm (6.4-7.7%), respectively. The MDC for these outcomes ranged respectively from 77.6 to 84.1 N (16.5-18.8%) and from 25.5 to 28.9 Nm (17.6-21.4%). The level of discomfort was low (median range: 7-10, IQR: 4-18). Conclusion The portable Q-Force ӀӀ is a comfortable, responsive, and relatively cheap device with excellent test-retest reliability. This device would be potentially suitable to measure isometric knee extensor strength in clinical settings

    The implementation of a physical activity counseling program in rehabilitation care:findings from the ReSpAct study

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    Purpose: This study aimed to evaluate the implementation of a physical activity counseling program in rehabilitation and to study heterogeneity in received counseling and investigate its association with changes in patients? physical activity outcomes. Methods: This prospective cohort study was conducted in 18 rehabilitation institutions. Data were collected using surveys completed by professionals (n= ?70) and patients (n?=?1719). Implementation was evaluated using different process outcomes: reach, dosage, satisfaction, maintenance. Patients? physical activity outcomes included changes in total minutes/week of physical activity. Latent class analyses were conducted to identify profiles of received counseling characteristics and multilevel models were used to investigate associations with physical activity outcomes. Results: 5873 Patients were provided with motivational interviewing-based counseling after rehabilitation. Professionals and patients were positive about the program. Sixteen institutions (89%) formally agreed to continue the program. The four identified profiles of counseling characteristics illustrate a large variation in received counseling among patients. No substantial differences in physical activity outcomes were found between profiles. Conclusion: After a three-year program period, the physical activity counseling centers were sustainably implemented in Dutch rehabilitation care. This study illustrated an innovative approach to assess heterogeneity in implementation outcomes (e.g., counseling profiles) in relation to program outcomes (e.g., physical activity)

    Implementing lifestyle-related treatment modalities in osteoarthritis care:Identification of implementation strategies using the Consolidated Framework for Implementation Research-Expert Recommendations for Implementing Change matching tool

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    Aims: Despite recommendations in international clinical guidelines, lifestyle-related treatment modalities (LRTMs) are currently underutilised in the conservative treatment of patients with hip and/or knee osteoarthritis. This study aimed to identify implementation strategies in order to address barriers to implementing LRTMs from the perspective of healthcare professionals (HCPs). Methods: The Consolidated Framework for Implementation Research (CFIR)-Expert Recommendations for Implementing Change (ERIC) Implementation Strategy Matching Tool was applied. First, previously identified influencing factors among primary and secondary HCPs were mapped onto the corresponding CFIR constructs/subconstructs by two researchers. Second, the CFIR-based barriers relevant for all HCPs were entered into the tool. Third, the CFIR-based barriers specific to one or more subgroups of HCPs served as additional input for the tool. Finally, a selection of ERIC implementation strategies was made based on the tool's output. Results: Fourteen implementation strategies were selected. The strategy most endorsed by the tool was ‘build a coalition’. Eight of the selected strategies belonged to the ERIC cluster ‘develop stakeholder interrelationships’. Other strategies were part of the clusters ‘use evaluative and iterative strategies’ (n = 3), ‘utilise financial strategies’ (n = 2), and ‘engage consumers’ (n = 1). Conclusions: The findings emphasise the importance of an interdisciplinary approach when addressing the implementation of LRTMs in osteoarthritis care. The final selection of implementation strategies forms the basis for a tailored implementation plan. Future work should focus on further operationalising the implementation strategies and evaluating the effectiveness of the resulting implementation plan.</p

    Natural Gas Compressibility Factor Measurement and Evaluation for High Pressure High Temperature Gas Reservoirs

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    The Natural gas compressibility factor is an important reservoir fluid property used in reservoir engineering computations either directly or indirectly in material balance calculations, well test analysis, gas reserve estimates, gas flow in lines and in numerical reservoir simulations. Existing gas compressibility factor correlations were derived using measured data at low to moderate pressures(less than 8, 000 psia) and temperatures (less than 212oF), and an extrapolation to High Pressure High temperature (HPHT) is doubtful. The need to understand and predict gas compressibility factor at HPHT has become increasingly important as exploration and production has moved to ever deeper formations where HPHT conditions are to be encountered. This paper presents laboratory measurement of gas compressibility factors at HPHT natural gas systems and the evaluation of some selected gas compressibility factors correlations. Samples of gas mixtures were collected from the high pressure gas reservoirs from the Niger Delta region of Nigeria. Vinci PVT Cell was used to measure the gas compressibility factors for a pressures ranging from 6,000 to 14,000 psia and temperatures at 270oF and 370oF. The new laboratory data was compared to some of the gas compressibility factor correlations/ models used in the petroleum industry. Results showed that majority of the correlations studied overestimated the gas compressibility factor at HPHT. Mean relative and absolute error analysis were done based on the temperature difference; it was found that the total mean relative and absolute errors for the 370o F cases are higher than those for 270oF. Among all the correlations assessed, Hall and Yarborough equation performed better than other existing correlations with a mean absolute error of 3.545 and relative error of -2.668 at 270oF. At 370oF, Beggs and Brills correlation predicted better than other correlations studied with a mean relative error of -4.77 and absolute error of 7.18
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