Objective: Despite the common occurrence of lower levels of physical activity and physical fitness in youth with spina bifida (SB) who use a wheelchair, there are very few tests available to measure and assess these levels. The purpose of this study was to determine reliability and the physiologic response of the 6-minute push test (6MPT) in youth with SB who self-propel a wheelchair. Methods: In this reliability and observational study, a sample of 53 youth with SB (5-19 years old; mean age = 13 years 7 months; 32 boys and 21 girls) who used a wheelchair performed 2 exercise tests: the 6MPT and shuttle ride test. Heart rate, minute ventilation, respiratory exchange ratio, and oxygen consumption were measured using a calibrated mobile gas analysis system and a heart rate monitor. For reliability, intraclass correlation coefficients (ICCs), SE of measurement, smallest detectable change for total covered distance, minute work, and heart rate were calculated. Physiologic response during the 6MPT was expressed as percentage of maximal values achieved during the shuttle ride test. Results: The ICCs for total distance and minute work were excellent (0.95 and 0.97, respectively), and the ICC for heart rate was good (0.81). The physiologic response during the 6MPT was 85% to 89% of maximal values, except for minute ventilation (70.6%). Conclusions: For most youth with SB who use a wheelchair for mobility or sports participation, the 6MPT is a reliable, functional performance test on a vigorous level of exercise. Impact: This is the first study to investigate physiologic response during the 6MPT in youth (with SB) who are wheelchair using. Clinicians can use the 6MPT to evaluate functional performance and help design effective exercise programs for youth with SB who are wheelchair using. Keywords: 6-minute push test; adolescent; disabled children; spinal diseases; wheelchairs.
Purpose: To evaluate the effects of a combination of wheelchair mobility skills (WMS) training and exercise training on physical activity (PA), WMS, confidence in wheelchair mobility, and physical fitness. Methods: Youth using a manual wheelchair (n = 60) participated in this practice-based intervention, with a waiting list period (16 weeks), exercise training (8 weeks), WMS training (8 weeks), and follow-up (16 weeks). Repeated measures included: PA (Activ8), WMS (Utrecht Pediatric Wheelchair Mobility Skills Test), confidence in wheelchair mobility (Wheelchair Mobility Confidence Scale), and physical fitness (cardiorespiratory fitness, (an)aerobic performance) and were analysed per outcome parameter using a multilevel model analyses. Differences between the waiting list and training period were determined with an unpaired sample t-test. Results: Multilevel model analysis showed significant positive effects for PA (p = 0.01), WMS (p < 0.001), confidence in wheelchair mobility (p < 0.001), aerobic (p < 0.001), and anaerobic performance (p < 0.001). Unpaired sample t-tests underscored these effects for PA (p < 0.01) and WMS (p < 0.001). There were no effects on cardiorespiratory fitness. The order of training (exercise before WMS) had a significant effect on confidence in wheelchair mobility. Conclusions: A combination of exercise and WMS training appears to have significant positive long-term effects on PA, WMS, confidence in wheelchair mobility, and (an)aerobic performance in youth using a manual wheelchair.Implications for rehabilitationExercise training and wheelchair mobility skills (WMS) training can lead to a sustained improvement in physical activity (PA) in youth using a manual wheelchair.These combined trainings can also lead to a sustained increase in WMS, confidence in wheelchair mobility, and (an)aerobic performance.More attention is needed in clinical practice and in research towards improving PA in youth using a manual wheelchair.
An important performance determinant in wheelchair sports is the power exchanged between the athletewheelchair combination and the environment, in short, mechanical power. Inertial measurement units (IMUs) might be used to estimate the exchanged mechanical power during wheelchair sports practice. However, to validly apply IMUs for mechanical power assessment in wheelchair sports, a well-founded and unambiguous theoretical framework is required that follows the dynamics of manual wheelchair propulsion. Therefore, this research has two goals. First, to present a theoretical framework that supports the use of IMUs to estimate power output via power balance equations. Second, to demonstrate the use of the IMU-based power estimates during wheelchair propulsion based on experimental data. Mechanical power during straight-line wheelchair propulsion on a treadmill was estimated using a wheel mounted IMU and was subsequently compared to optical motion capture data serving as a reference. IMU-based power was calculated from rolling resistance (estimated from drag tests) and change in kinetic energy (estimated using wheelchair velocity and wheelchair acceleration). The results reveal no significant difference between reference power values and the proposed IMU-based power (1.8% mean difference, N.S.). As the estimated rolling resistance shows a 0.9–1.7% underestimation, over time, IMU-based power will be slightly underestimated as well. To conclude, the theoretical framework and the resulting IMU model seems to provide acceptable estimates of mechanical power during straight-line wheelchair propulsion in wheelchair (sports) practice, and it is an important first step towards feasible power estimations in all wheelchair sports situations.
