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IPS position paper: preconditioning for the conjugate gradient method. IPS progress report. Gentzsch Eds. Cytometry , 16 , Modelling and simulation. Modelling and Simulation. Two-dimensional Crystallisation on spherical surfaces. Gruber Eds. Geneva, Switzerland: European Physical Society. Simulated Annealing for N-body Systems. Presentation on the status of Parasol. Map design report. MAP position paper. Smit, L. Zuidervaart Eds. SAD progress report. SAD technical report. BLAS: Basic linear algebra subsystems. Amsterdam: Department of Computersystems, University of Amsterdam.
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The SDC was, respectively, 5. The results are shown in tables IV and V. A secondary aim was to examine the reliability of the best test study 2. Because of this, reliability was determined for the GWPT. Best test performance and feasibility study 1 The preference for wheelchair propulsion compared with arm cranking in this study is similar to the results of a study by Verschuren et al.
Results for HR peak also remain equivocal, both higher HR peak during wheelchair propulsion27, 31 and higher HRpeak during arm cranking32 have been reported. The results of this study combined with the literature about children and adolescents support a change in functional propelling protocols, as suggested by Bar-or.
Using the Cortex Metamax during the GACT was also complicated for older children and adolescents, due to the large dimensions of the arm crank ergometer, the flow sensor and face mask, which would probably have limited their maximum effort. Since we wanted to include children aged 6 years and over, this aspect supported our preference for the GWPT. However, 1 adolescent had to stop the GWPT prematurely, due to pain in his forearms. This individual was community ambulatory; he used his wheelchair only for long distances, which may explain the pain he experienced during the GWPT.
In this study VO2peak and HR peak were the main outcome parameters. Power output is also an important outcome parameter often used during aerobic fitness testing. However, it was not possible to report power output for the GWPT on the wheelchair ergometer. Measuring the resistance of the wheelchair on the ergometer is difficult, resulting in problems with measuring power output on the wheelchair ergometer.
This problem could have been solved by using a wheelchair propulsion test on a treadmill, as is often used in adults with spinal cord injury who use a wheelchair. Wheelchair propulsion can also be measured through field tests, such as the multistage field test and the Shuttle Ride Test.
We decided, however, that we first had to determine the best laboratory test for measuring VO2peak in children and adolescents with SB who use a wheelchair, as field testing may be influenced by, for example, wheelchair skills or anaerobic performance. Also, for adults who use a wheelchair the criteria for maximal aerobic fitness testing are unclear. In this study the protocol according to Rossiter et al. No differences were found between VO2peak and VO2supramaximal, assuming that maximal effort was achieved in both tests. However, 2 participants 7 and 10 achieved both relatively low HR peak and bpm, respectively and low RERpeak values 0.
Future research should determine the criteria for maximal aerobic fitness testing in children and adolescents who use a wheelchair, so that these criteria can be used in both research and care. We also tried to apply the OMNI scale of perceived exertion35 because research indicated a relationship between the rate of perceived exertion and VO2peak.
The SDC was 5. No literature is available about intervention studies regarding VO2peak in children and adolescents with SB who use a wheelchair. Future research may provide information about progression in VO2peak after training in children and adolescents with SB and, consequently, about interpretation of the SDC. Study limitations This study has several limitations. The first part of this pilot study involved only 13 participants, which may have resulted in clinical, yet not statistically significant, differences.
However, when combining the results with those of the reliability study, the outcomes for VO2peak appear to be consistent and even higher for HR peak. Therefore, and supported by the best available evidence, we consider the choice in favour of GWPT to be justified. Another possible limitation is the use of fixed protocols for both the GACT and the GWPT for all participants, as this did not take into account differences in lesion level, age, height and physical activity level.
This may have influenced the duration of the tests, and therefore also VO2peak and HRpeak. It is important to expand our knowledge and experience regarding aerobic fitness testing in children who use a wheelchair, so that guidelines for more individual protocols may be developed in the future, comparable to the Godfrey protocols for children on a cycle ergometer. Furthermore, other clinimetric properties of the GWPT remain unclear, such as the minimal clinically important difference and responsiveness; these aspects may be the focus of future research.
In conclusion, this pilot study shows higher HR peak and VO2peak in children and adolescents with SB who are using a wheelchair when tested during wheelchair propulsion compared with arm cranking. The GWPT showed good reliability. We recommend performing a wheelchair propulsion test for aerobic fitness testing in children and adolescents who use a wheelchair. Low cardiorespiratory fitness is a strong predictor for clustering of cardiovas cular disease risk factors in children independent of country, age and sex. Eur J Cardiovasc Prev Rehabil ; — The Utrecht approach to exercise in chronic childhood conditions: the decade in review.
Pediatr Phys Ther ; 2— Accelerometry based activity spectrum in persons with chronic physical conditions. Arch Phys Med Rehabil ; — Health-related physical fitness of ambulatory adolescents and young adults with spastic cerebral palsy. J Rehabil Med ; — J Pediatr ; — J Rehabil Med ; 70— Phys Ther ; — Aerobic and anaerobic exercise capacity in children with juvenile idiopathic arthritis. Arthritis Rheum ; — Identification of a core set of exercise tests for children and adolescents with cerebral palsy: A Delphi survey of researchers and clinicians.
Dev Med Child Neurol ; — Reliability and validity of data for 2 newly developed shuttle run tests in children with cerebral palsy. Sports Med ; 77— Reproducibility and Validity of the meter shuttle ride test in wheelchairbound children and adolescents with cerebral palsy. Bar-or o. Med Sci Sports Exerc ; — Obesity across the lifespan among persons with spina bifida. Disabil Rehabil ; — Assessing change in body composition in children with duchenne muscular dystrophy: anthropometry and bioelectrical impedance analysis versus dual-energy X-ray absorptiometry. Clin Nutr ; — Examination of the Metamax I and II oxygen analysers during exercise studies in the laboratory.
Scand J Clin Lab Invest ; — Bar-or o, Rowland T. Pediatric Exercise Medicine. From physiologic principles to healthcare application. Champaign, Il: Human kinetics; A test to establish maximumO2 uptake despite no plateau in the O2 uptake response to ramp incremental exercise. J Appl Physiol ; — Supramaximal verification of peak oxygen uptake in adolescents with cystic fibrosis. Pediatr Phys Ther ; 15— Treadmill testing of children who have spina bifida and are ambulatory: does peak oxygen uptake reflect maximum oxygen uptake?
Measurement in medicine. Practical guides to biostatistics and epidemiology. New York: Cambridge University Press; When to use agreement versus reliability measures. J Clin Epidemiol ; — International standards for neurological and functional classification of spinal cord injury. American Spinal Injury Association.
Spinal Cord ; — Clin Rehabil ; — Maximal response of wheelchair-confined subjects to four types of arm exercise. Arch Phys Med Rehabil ; 10— Relationship between maximal oxygen uptake on different ergometers, lean arm volume and strength in paraplegic subjects. Bhambhani Y. Physiology of wheelchair racing in athletes with spinal cord injury. Sports Med ; 23— The maximum physiological responses during incremental wheelchair and arm cranking exercise in male paraplegics. Physical capacity in wheelchair-dependent persons with a spinal cord injury: a critical review of the literature.
Arm crank versus wheelchair treadmill ergometry to evaluate the performance of paraplegics. Paraplegia ; — Cardiorespiratory and perceptual responses to arm crank and wheelchair exercise using various handrims in male paraplegics. Res Q Exerc Sport ; — Psychosocial outcomes of children and adolescents with early-onset spinal cord injury and those with spina bifida. Pediatr Phys ther ; — The multi-stage fitness test as a predictor of endurance fitness in wheelchair athletes. J Sports Sci ; — Prediction of peak oxygen uptake from differentiated ratings of perceived exertion during wheelchair propulsion in trained wheelchair sportspersons.
Eur J Appl Physiol ; — Dennis M, Barnes MA. The cognitive phenotype of spina bifida meningomyelocele. Dev Disabil Res Rev ; 31— Executive functioning and psychological adjustment in children and youth with spina bifida. Child Neuropsychol ; — Neurorehabil Neural repair ; — Exercise training programs to improve hand rim wheelchair propulsion capacity: a systematic review. Objective To estimate validity and reliability of the Shuttle Ride Test in youth with spina bifida who use a wheelchair for mobility and sport.
Results No significant differences were found between the Graded Wheelchair Propulsion Test and Shuttle Ride Test for most cardiorespiratory responses. High correlations were found between number of shuttles completed and skill related fitness tests 0. ICCs were high 0.
Conclusion When measuring VO2peak directly by using a mobile gas analyses system, the Shuttle Ride Test is highly valid for testing VO2peak in youth with spina bifida who use a wheelchair for mobility and sport. The outcome measure shuttles represents aerobic fitness, while also being highly correlated with both anaerobic performance and agility. It is not possible to predict VO2peak accurately using the number of shuttles completed. Moreover, the Shuttle Ride Test is highly reliable in youth with spina bifida with a good smallest detectable change for the number of shuttles completed.
Valid and reliable field-based tests will contribute to evaluation of interventions and the clinical reasoning process of pediatric physical therapists concerning aerobic fitness. The Shuttle Ride Test SRiT , derived from the well-known and frequently used Shuttle Run Test in youth who are ambulatory, has been used in other clinical populations and seems to be the most appropriate maximal aerobic field test for measuring aerobic fitness in youth with SB who use a wheelchair for mobility and sport. The main outcome measure is the number of shuttles they achieved, with one shuttle corresponding to approximately one minute of wheelchair propulsion.
A shuttle is a stage with a constant speed and the speed is increased approximately every 1 minute. This principle has been used over decades in field exercise tests in children. While criterion validity concerns comparing VO2peak measures between the SRiT and the GWPT, most pediatric physical therapists and other clinicians do not have the access to a mobile gas analysis system when assessing the SRiT. They have to use the metric shuttle during their clinical reasoning process. Evidence in athletes who are wheelchairusing, showed that it is difficult to predict VO2peak using the distance travelled during the incremental SRiT.
Therefore, it is interesting to evaluate the possibility to predict VO2peak achieved during the SRiT by using the outcome measure shuttles and to test the hypotheses of moderate to high correlations between the shuttles and anaerobic performance, agility, personal factors and wheelchair features in children with SB who use a wheelchair for mobility and sport. This information will help pediatric physical therapists to interpret the outcome measure shuttles during their clinical reasoning process. Besides validity, reliability is an important measurement property and highly relevant when evaluating the effects of training.
Therefore the aims of this study are 1 to estimate the criterion validity of the SRiT by comparing cardiorespiratory responses of the SRiT to the GWPT using a mobile gas analysis system, 2 to estimate the construct validity of the metric shuttles by predicting VO2peak and correlating the shuttles with anaerobic performance, agility, personal factors and wheelchair features and 3 to estimate the reliability of the SRiT in youth with SB who use a wheelchair for mobility and sport. Participants were included if they were diagnosed with SB, years of age during enrollment, and were able to follow instructions of the measurements.
They had to self-propel a wheelchair during daily life, long distances or sports participation, meaning that they had to be experienced wheelchair-users. Participants were excluded if any medical event was present that intervened with testing outcome. Children aged 12 years and over and all parents had to sign informed consent, as this is required by the Dutch law and regulations. The participants of the validity study were measured twice one day for the GWPT and one day for the SRiT , those who also participated in the reliability study were measured three times a third day for the second SRiT , with three days to one week between testing.
All field tests were measured either in the gymnasium of the HU University of Applied Sciences or in a gymnasium nearby the participants home. The participants were always tested in similar conditions: in their own wheelchair, with the same tire pressure maximum that was allowed and on the same floor. The testing order differed between the participants, because of practical aspects like availability of the gymnasium or laboratory.
Only one maximal aerobic exercise test was performed on a single day and the maximal aerobic exercise test was always the last test of that day. Between the other short duration tests, a resting period of at least five minutes was scheduled. A standard questionnaire recorded age, gender, type of SB, lesion level, use of wheelchair and type of wheelchair. Arm span while seated as proxy for height was measured through the use of a non-stretchable tape middle finger-tip to middle finger-tip as recommended in children who are wheelchair-using, because of possible contractures in hips and knees when lying supine.
The Cortex Metamax has been used in multiple studies regarding exercise testing in youth who use a wheelchair for mobility and sport and is valid and reliable for measuring gas-exchange parameters during exercise. The participants had to maintain their self-selected comfortable wheelchair propulsion speed between rpm , while the resistance was increased by 0. The starting speed was 2. The main performance outcome measure of the SRiT is the total number of achieved shuttles ranging from 0.
The children had to continue until they failed to reach the line within 1. All participants were accompanied by the test leader to help pace themselves and to encourage them to achieve maximal effort. HR peak was defined as the highest value during the tests. The ventilator anaerobic threshold VAT was determined by the ventilatory equivalents method. When results were uncertain, the V-slope method was used to verify the VAT. They had 10 seconds to turn and prepare for the next sprint, between every sprint. The time of a 15 meter sprint was manually recorded with a stopwatch to one hundredth of a second.
Mean power MP was defined as the average power of the four sprints and was used as the outcome measure. During the slalom test, participants had to slalom between four cones that were 1. Time taken to perform the tests was manually recorded with a stopwatch to one hundredth of a second and was used as the outcome measure. Statistical analysis Power analysis We estimated the range of sample values given a hypothesized population Intraclass Correlation Coefficient ICC and sample size by a general method, prior to data collection.
First, normality of the data was checked with histograms and Q-Q plots. If there was uncertainty about the normality of the data, bootstrapping with a bias corrected accelerated BCa confidence interval was used to confirm the results. Possible independent variables were personal factors gender, age, weight, height, BMI , wheelchair features wheelchair mass, tire pressure and factors obtained during the SRiT HR peak, shuttles.
First, linearity of relationships between VO2peak and the independent variables was assessed with scatterplots and quantified with Pearson correlation coefficients. Subsequently, a weighted stepwise forward multiple regression analysis was performed to identify the independent variables that contributed to the prediction of VO2peak during the SRiT.
The correlations between the number of achieved shuttles of the SRiT and the anaerobic performance Mean Power of the MPST and agility seconds of the 10x5MST and seconds of the slalom test were established by Pearson correlation coefficients. Additionally, possible relations between the number of achieved shuttles during the SRiT and.
A,28, 29 after checking for normality. These limits of agreement give an indication of the absolute agreement between the two measurements and can be interpreted as a true change, comparable to the SDC. For the reliability part, 28 participants completed both the SRiT and the retest. A small number of participants were community or household ambulatory and thus self-propelling a wheelchair for long distances or sports participation. The majority were therapeutic or non-ambulatory, meaning that they were self-propelling a wheelchair during daily life.
Table 3. Two participants for which the GWPT was too heavy and the SRiT was too difficult were 5 years and 9 months and 6 years old respectively. Construct Validity A total of 38 participants achieved the subjective criteria for maximal effort during the first SRiT and data of these participants were used for predicting absolute VO2peak. Subsequently, height, weight and shuttles were used as independent variables in the weighted multiple linear regression analysis.
We used a weighted regression, because of heteroscedasticity during a normal multiple linear regression. Looking at individual prediction intervals, we saw a mean range of 0. The results of the weighted regression are presented in table 4. For agreement, the SDC for the number of achieved shuttles is 1. The CV for absolute and relative VO2peak is 6. Table 5. Correlation of number of achieved shuttles during the SRiT with skill-related fitness tests, personal factors and wheelchair features. To our knowledge, only one other study investigated the validity of the SRiT in youth who are wheelchair using so far.
Verschuren et al. During the GWPT, the child has to propel with a continuous speed and increasing load while during the SRiT, the child has to increase his or her speed. Future research may clarify these different physiologic responses during incremental exercise testing protocols in youth who are wheelchair using. Moreover, this would also help to understand which objective criteria for maximal aerobic exercise testing should be used in this population. In this study we used subjective criteria for maximal exercise testing17 to conclude if a child performed maximal at either the GWPT or the SRiT.
We only included data in the analyses, if the subjective criteria were met. There were no specific characteristics regarding participants who did not meet the subjective criteria, so unfortunately we were not able to conclude in which children the SRiT cannot be used for maximal cardiorespiratory exercise testing.
We also tried to use the OMNI-scale of perceived exertion, 41 unfortunately, these results were unreliable due to the cognitive impairments often present in youth with SB. To our knowledge, no study in youth who use a wheelchair for mobility and sport tried to predict VO2peak using the number of achieved shuttles during the SRiT so far. A recent meta-analysis concerning the original meter Shuttle Run Test for typically developing children showed a moderate to high criterion-related validity for estimating VO2peak. Of course, our relatively small sample size of 38 should be taken into account, so our results should be interpreted as tentative.
We then tried to clarify the construct of the outcome measure shuttle, mostly used by pediatric physical therapists because they do not have the availability of a mobile gas analyses system. Unfortunately, it was not possible to explain which independent variables contribute to the number of achieved shuttles using a multiple linear regression, due to multicollinearity between the skill-related fitness tests.
The moderate to high correlations between the number of achieved shuttles and both anaerobic performance and agility confirm the hypothesis generated by Verschuren et al. Another interesting subject would be to analyze whether the increase in VO2 is equal during every incremental shuttle of the SRiT. This might help to analyze which part of the SRiT is explained by VO2-uptake and which part may be explained by, for example, anaerobic performance or agility.
It was interesting to see the significant negative correlation between wheelchair mass and number of achieved shuttles, indicating the importance of light weight wheelchairs. In our previous study about skill related fitness tests in youth with SB,14 we also found that a lighter wheelchair mass contributed to the distance traveled during one push. Literature about adults confirm the relevance of light weight wheelchairs. Unfortunately, we were not able to take wheelchair features as rolling resistance, internal resistance and the wheelchair configuration into account.
Future research may take these wheelchair features into account. The results regarding the reliability of the achieved shuttles during the SRiT are comparable with wheelchair using youth with CP and OI. It is not possible to predict. VO2peak accurately using the number of achieved shuttles. For pediatric physical therapists using the metric shuttles, the number of achieved shuttles represents aerobic fitness and is moderately correlated with anaerobic performance and highly correlated with agility. Because the SRiT is highly reliable and has a good SDC for the number of achieved shuttles, the SRiT can be used to monitor effectiveness of interventions to improve aerobic performance in youth with SB who use a wheelchair for mobility and sport.
We would like to thank all children, adolescents and their parents for their enthusiastic participation. Also all students who participated in this study, as part of their thesis, are being acknowledged. In: Anonymous Physical activity, fitness, and health consensus statement. Champaign, IL: Human Kinetics. Limiting factors in peak oxygen uptake and the relationship with functional ambulation in ambulating children with spina bifida.
Eur J Appl Physiol ; The multistage 20 metre shuttle run test for aerobic fitness. J Sports Sci ;6: J Sports Sci ; Determinants of shuttle run performance in the prediction of peak VO2 in wheelchair users. Scand J Clin Lab Invest ; Paap D, Takken T. Reference values for cardiopulmonary exercise testing in healthy adults: a systematic review. Expert Rev Cardiovasc Ther ; Comparing four non-invasive methods to determine the ventilatory anaerobic threshold during cardiopulmonary exercise testing in children with congenital heart or lung disease.
Clin Physiol Funct Imaging ; Measurement and validity of the ventilatory threshold in patients with congenital heart disease. Pediatr Cardiol ; A new method for detecting anaerobic threshold by gas exchange. J Appl Physiol ; Reliability for running tests for measuring agility and anaerobic muscle power in children and adolescents with cerebral palsy.
Intraclass correlations: uses in assessing rater reliability. Psychol Bull ; Cohen J. Field A. Practical Guide to Biostatistics and Epidemiology. J Clin Epidemiol ; Norwalk, CT: Appleton and Lange. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet ;1: Atkinson G, Nevill AM. Statistical methods for assessing measurement error reliability in variables relevant to sports medicine. Three-dimensional digital stereophotogrammetry: a reliable and valid technique for measuring scar surface area.
Plast Reconstr Surg ; Hopkins WG. Reliability of treadmill measures and criteria to determine VO2max in prepubertal girls. Repeatability of peak oxygen uptake in children who are healthy. A practical approach to Bland-Altman plots and variation coefficients for log transformed variables. Spinal Cord ; J Sports Sci Med ; Criterion-related validity of field-based fitness tests in youth: a systematic review.
Br J Sports Med ; A multistage field test of wheelchair users for evaluation of fitness and prediction of peak oxygen consumption. J Rehabil Res Dev ; Babyak MA. What you see may not be what you get: a brief, nontechnical introduction to overfitting in regression-type models. Psychosom Med ; Manual wheeled mobility-current and future developments from the human engineering research laboratories. Biomechanics and physiology in active manual wheelchair propulsion. Med Eng Phys ; Manual wheelchairs: Research and innovation in rehabilitation, sports, daily life and health.
Validity and reliability of skill-related fitness tests for wheelchair-using youth with spina bifida Manon A. Kruitwagen, MSc,5 Janke F. Design Clinimetric study.
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Setting Rehabilitation centers, SB outpatient services, and private practices. Interventions Not applicable. Main Outcome Measures Construct validity of the MPST was determined by comparing results with the armcranking Wingate Anaerobic Test WAnT using paired t tests and Pearson correlation coefficients, while content validity was assessed using time- based criteria for anaerobic testing.
Construct validity of the 10x5MST, slalom test, and 1SPT was analyzed by hypothesis testing using Pearson correlation coefficients and multiple regression. The 10x5MST and slalom test are valid and reliable for measuring agility. For the 1SPT, both validity and reliability are questionable. In daily life of wheelchair-using youth, skill-related fitness is reflected in activities such as playing outside or playing wheelchair sports. This assessment enhances clinical reasoning and supports evaluation of training programs.
Field-based testing does not require expensive equipment, is task specific, and children use their own wheelchair, which is of great importance because it takes into account the wheelchair-user interface integration. In ambulatory youth with CP this results in 6 sprints, while for wheelchairusing youth with CP the total number of sprints is 3. However, identifying the relationships between these different skill-related fitness tests contributes to clarification of the underlying constructs. Therefore, the aims of this study were to.
Overview of testing for field-based skill-related fitness tests in wheelchair-using youth with SB. Concerning content validity, we hypothesized that the total number of sprints of the original ambulatory version of the MPST 6 sprints should be adjusted to a lower number. For construct validity, we hypothesized high correlations between the MPST and the criterion standard laboratory assessment for anaerobic power, the arm-cranking WAnT.
In addition, we hypothesized high to excellent correlations between the 10x5MST and slalom test, as both tests measure agility. Moreover, we hypothesized that wheelchair features such as wheelchair mass and physical factors such as muscle strength contribute to the 1SPT. Procedures Figure 1 presents the clinimetric properties evaluated in this study. Participants were assessed twice validity part or 3 times validity and reliability part , with 3 days to 1 week between testing moments. The tester was a pediatric physical therapist, and both the tester and the participants were unaware of previous results.
Age, sex, type of SB, lesion level, use of wheelchair, and type of wheelchair were recorded through a standard questionnaire. An electronic wheelchair scalea was used to register body mass and wheelchair mass. Arm span length middle fingertip to middle fingertip was used as an indicator for height as recommended in wheelchair-using people, using nonstretchable tape. Every test started with a habituation period during which participants were familiarized with the test, with 5 minutes of resting before starting the actual measurement.
Figure 2 presents an overview of the skill-related fitness tests. Muscle Power Sprint Test Participants were instructed to propel a distance of 15m marked by 2 lines as fast as possible. This was repeated 6 times. Between every sprint, participants had 10 seconds to turn and prepare. The main outcome measure was the manually recorded time per m sprint to. The highest power is presented as peak power PP , while the average power over the sprints is presented as mean power MP.
During the first 2 minutes warmup phase , no breaking force was applied and participants had to crank at a comfortable speed. During the last 10 seconds of the warmup, a countdown was given to allow them to maximize their pace, after which a braking force of. The main outcome measure was the manually recorded time to.
Participants had to turn at the end, sprint back, and repeat the same procedure once. The main outcome measure was the distance in centimeters measured from the starting line to the most anterior point of the front wheel furthest away. The mean distance of 3 trials was calculated. Statistical analysis Before the data collection, a sample size estimation was performed. This sample size estimation was based on the reliability part of the study. Data were analyzed for normality using quantile-quantile plots, histograms, and scatterplots.
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Consequently, this number of sprints was used for calculating the MP and PP. In addition, we analyzed the contribution of wheelchair features and physical factors to the distance covered during the 1SPT. Second, univariate analyses were quantified with Pearson correlation coefficients to select a maximum of 4 independent variables in the multiple regression analyses, to ensure stability of the parameter estimates given the sample size. Subsequently, a forward stepwise multiple regression analysis was performed.
ICCs of 0.
Table 2 lists the reasons for missing data. Therefore, the calculations of MP and PP were based on 4 sprints. Subsequently, sex, wheelchair mass, and total upper muscle strength were used as independent variables in the regression analyses. Heteroscedasticity and multicollinearity assumptions were not violated. The SEMs varied from 3. Table 2. Number of participants of the skill-related fitness tests in wheelchair-using youth with SB. Furthermore, 6 participants from our study were not able to perform the arm-cranking WAnT because the ergometer proportions did not fit the participants, while all participants were able to perform the MPST.
Moreover, the MPST is inexpensive and easy to administer, and therefore a good field-based alternative for the lab-based arm-cranking WAnT when measuring anaerobic performance in wheelchair-using youth with SB. For construct validity, the excellent correlation between the 10x5MST and slalom test supports the hypothesis that both tests measure agility. Since it was hypothesized that the 1SPT measures propelling technique, wheelchair features, and physical factors, we analyzed the contribution of various variables in relation to the distance measured.
Subsequently, total upper muscle strength physical factor also seemed to play an important role. A limitation was the inability to measure propulsion technique in biomechanical terms and the friction between the wheel and the floor; these variables appear to be important aspects contributing to the distance covered during the 1SPT. Future research may be able to take these biomechanical aspects into account and provide more insight into the different factors that contribute to the distance covered in 1 stroke. These SDCs are important for clinicians, because they provide information about the true change of an individual.
Study limitations Certain limitations should be considered when interpreting the results of this study. First, no objective criteria were available to determine whether participants performed maximally during all tests. However, this manual recording of time is highly representative of clinical practice. In addition, test and retest were performed by the same tester, so only intrarater reliability can be interpreted.
Clinics or rehabilitation centers are advised to determine the interrater reliability between therapists working at their clinic. It shows good construct validity with the arm-cranking WAnT for measuring anaerobic performance. Even though reliability of the MPST is high, its clinical use is questionable because of large measurement errors. The construct validity of the 10x5MST and slalom test is good. The reliability of the 10x5MST and slalom test is high, and both tests have an acceptable measurement error. Depending on individual patient goals, clinicians can choose which test to use for measuring agility.
The clinical use of the 1SPT is still questionable because the construct is unclear and measurement error seems quite large. Suppliers a. Lode Angio; Procare BV. Technics-Center for Innovative Technics. Pediatr Phys Ther ; Pediatr Neurosurg ; Clin Rehabil ; Phys Ther ; Physical activity, exercise, and physical fitness: definitions and distinctions for health-related research. Public Health Rep ; Manual wheelchair use: bouts of mobility in everyday life. Rehabil Res Pract ; Systematic review of the clinimetric properties of laboratory- and field-based aerobic and anaerobic fitness measures in children with cerebral palsy.
Arch Phys Med Rehabil ; Validity of the muscle power sprint test in ambulatory youth with cerebral palsy. Reproducibility of two functional field exercise tests for children with cerebral palsy who self-propel a manual wheelchair. Dev Med Child Neurol ; Reliability and validity of short-term performance tests for wheelchair-using children and adolescents with cerebral palsy. Sports Med ; The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes.
J Clin Epidemiol ; The Wingate Anaerobic Test: an update on methodology, reliability and validity. Hutzler Y. Physical performance of elite wheelchair basketball players in armcranking ergometry and in selected wheeling tasks. Paraplegia ; Measurement reliability of functional tasks for persons who self-propel a manual wheelchair.
J Rehabil Med ; Disabil Rehabil ; Reference values of maximum isometric muscle force obtained in children aged years by hand-held dynamometry. Neuromuscul Disord ; Inter-tester reliability and precision of manual muscle testing and hand-held dynamometry in lower limb muscles of children with spina bifida. Phys Occup Ther Pediatr ; Psychol Bull ; Measurement in medicine: practical guide to biostatistics and epidemiology.
New York: Cambridge Univ Pr; Statistical power analysis for the behavioural sciences. Hillsdale: Lawrence Erlbaum Associates; Med Eng Phys ; Physical behavior in wheelchair-using youth with spina bifida: an observational study Manon AT. Bloemen,1 Rita HJG. Backx,6 Marleen Vos,1 Janke F.
ABSTRACT Aim To quantify physical behavior in wheelchair-using youth with spina bifida SB and evaluate the intensity of activities Method VitaMove data of 34 and Actiheart data of 36 wheelchair-using for daily life, long distances or sports youth years with SB were collected to assess type of activity and intensity. Type of activity was presented as time spent in sedentary activities and physical activities and compared to reference data. Intensity was analyzed according to the percentage of heartrate reserve. Data of 25 participants could be used to combine type of activity and intensity.
Results Participants spent more time in sedentary activities The intensities per activity varied extensively between participants. Interpretation Wheelchair-using youth shows unfavorable physical behavior, with weekend days being even more unfavorable compared to school days. The different intensities during activities indicate the importance of individually tailored assessments and interventions. What this paper adds - Quantification of physical behavior in wheelchair-using youth with spina bifida. For example, sedentary time was associated with unfavorable body composition, decreased fitness, higher clustered cardio metabolic risk scores, and decreased academic achievement.
Different concepts can be considered when measuring physical behavior, such as type of activity which can further be analyzed in terms of duration and the physiologic response of the body to physical behavior, representing the intensity. All these dimensions require different equipment. The intensity of activities might be different in clinical populations compared to typically developing peers because of the severity of the disability. While it could seem that wheelchair-using youth is less active as defined by time spent in certain types of activities, the intensity level could show other results.
Understanding physical behavior both type of activity and intensity and the intensity. Therefore, the aims of this study were to quantify in wheelchair-using youth with SB: 1. Participants were recruited in the Netherlands and were included if they were diagnosed with SB, years of age during enrollment, used a manual wheelchair during daily life, for long distances, or for sports participation and if they were able to follow test instructions.
Participants were excluded if they had any events that might intervene with the outcomes of the testing. All parents and participants aged 12 years and older signed informed consent. The VitaMove is an ambulatory monitoring system with wireless body-fixed accelerometers Freescale MMAQ, Denver, USA which is highly valid for measuring mobility-related activities in wheelchair-using youth as well as in able-bodied people.
The following activities can be distinguished: lying, sitting, wheeling, handbiking and non-cyclic moving. Participants who were both walking and wheelchairusing wore two additional recorders, one on each thigh, to additionally distinguish standing, walking, running, and biking. Detailed descriptions of the configuration and analysis have been described elsewhere. It is a highly valid device for measuring heartrate HR and is easy to use in wheelchair-using children with SB. Protocol Participants were asked to wear both devices simultaneously for two school days and one weekend day from the moment they got dressed until they went to bed, except during bathing and swimming.
They also were asked to keep an activity diary so we could to correct for swimming and check for peculiarities in the data. To avoid measurement bias, we did not explain that we were measuring physical behavior beforehand and instructed the participants to continue their ordinary life. Data analysis A minimum duration of one day and a minimum wear time of 8 hours per day was required to be included in the analysis. Type and total duration of activities were obtained from the VitaMove.
Sitting and lying were clustered and presented as sedentary activities. Walking, running, wheeling, hand biking and non-cyclic moving were clustered and presented as physical activities. Standing was separately analyzed. All activities were expressed as a percentage of wear time, to control for differences in total wear time between participants. VitaMove data of the participants were compared to reference activity monitor data of 20 typically developing youths aged 8 — 20 years who had worn the VitaMove during two school days hour measurement.
These data were available from previous studies at the department of Rehabilitation Medicine at Erasmus University Medical Center Rotterdam. If either a higher HRpeak or a lower HR rest was measured by the Actiheart in daily life, these values were used. Statistical analyses Histograms, QQ-plots and the Shapiro Wilk test showed that data of the Vitamove and Actiheart separately were not normally distributed.
Wilcoxon Signed Rank tests showed no differences between the first and second school day, justifying the use of data when only one school day was available. When data of two school days were available, data were averaged. Differences between school days and weekend days were tested with the Wilcoxon Signed Rank test. For type of activity, the durations were presented as median, interquartile range IQR and minimum and maximum. For comparing sedentary activities and physical activities between our participants and typically developing peers, differences were analyzed using linear regression correcting for gender and age.
For intensity, we presented median, interquartile range IQR , minimum and maximum and also described how many of our participants met the physical activity guideline at least 60 minutes per day on at least moderate intensity of which at least 30 minutes at vigorous intensity. We upsampled the data of the Actiheart so the second intervals of the Actiheart could be combined with the 1-second intervals of the VitaMove.
VitaMove data of 34 participants could be used for the analysis of the type of activities and Actiheart data of 36 participants could be used for the analysis of the intensity of physical behavior. For intensity of different activities, data of 25 participants could be combined VitaMove and Actiheart Table 1. Missing data were caused by not properly functioning of the devices, wear time less than 8 hours f. Wheelchair-using participants with SB spent a significantly higher amount of time in sedentary activities This corresponds with approximately 72 minutes in physical activities on a school day for wheelchair-using youth with SB compared to minutes for typically developing peers.
Percentage of time spend in different types of activities on a school day, comparing wheelchair-using youth with SB to typically developing peers. Difference in characteristics between participants with SB and typically developing children was tested with a two sample t-test age, weight, height and chi-square gender. Differences in physical-active activities and sedentary activities were analyzed with regression analyses corrected for age and gender.
The results for intensity of physical behavior are presented in table 4. Overall, the intensity was significantly higher during a school day compared to a weekend day. Overall, the intensity varied extensively per activity as can be seen by the broad ranges reported in table 5. An example of the strain of different activities for a wheelchair-using adolescent during a school day and weekend day is presented in figure 1 and 2.
These figures illustrate the differences in type of activities and intensity during a school day and a weekend day. Duration of the types of activities in wheelchair-using youth with SB, separately presented for a school day and a weekend day. Wear time is total wear time in hours, presented as mean standard deviation. Differences between a school day and weekend day for wear time was tested with the paired samples t-test. Differences between a school day and weekend day for physical activities and sedentary activities were tested with the Wilcoxon Signed Rank test.
Table 4. Intensity of physical behavior for wheelchair-youth with SB, separately presented for school days and weekend days. Figure 1. Figure 2. Wheelchair-using youth with SB spent more time in sedentary activities and less time in physical activities compared to typically developing peers. When comparing our results to wheelchairusing adolescents and young adults with SB, similar percentages of time in sedentary activities and physical activities were reported.
Further longitudinal research may focus at the effect of age on physical behavior. When comparing our results to ambulatory youth and young adults with Cerebral Palsy CP , these latter seem to be less sedentary and more physically active than our wheelchair-using participants with SB. A recent meta-analysis in adults showed that high levels of moderate physical activity intensity attenuates increased risk of death associated with high sitting time.
Even though our participants were wheelchair-using and diagnosed with SB, there was no medical reason why they would not be able to perform physical activities. As evidence has shown that the activity levels during childhood track into adulthood, the challenge seems to be how to improve physical behavior during early childhood in wheelchair-using youth with SB. The participants might be fatigued after a whole school week and thus needing to rest during the weekend. It might also be, however, that there are not enough possibilities to be physically active during weekends or that there is not enough stimulation in the direct environment.
Recent literature showed a variety of important facilitators and barriers when aiming to improve physical activity in youth with SB. Intensity of the activities varied extensively between the wheelchair-using participants, with for example wheeling and hand biking ranging from very light intensities to near to maximal intensities. This again underlines the individual approach needed when aiming to improve physical behavior in wheelchair-using youth with SB. It seems. In general, activities as wheeling and hand biking are activities that can be adequate in achieving higher intensities.
Interestingly, the variability from very light to near to maximal intensity was also found for sitting. This might be due to the fact that HR responses during exercise are slightly delayed and thus not fully in line with the activity that is performed. Similarly, if a participant stops wheeling and thus sits according to the VitaMove , it takes time for the HR to recover and return to its resting rate. A strength of this study was that physical behavior was measured with valid objective devices, using both the VitaMove and the Actiheart simultaneously.
By doing so, we were able to measure sedentary activities and physical activities, as well as intensity. It offered the unique possibility of combining these results into intensity during several activities. Of course there are also limitations using these instruments. In some cases the devices did not function properly but there were also some participants who did not want to wear these devices. Secondly, we used the HRR for the intensity, however, the variability of the HR is also related to other aspects such as emotional stress.
There is still a huge challenge in developing valid and reliable activity monitors that can be easily used in daily clinical practice in wheelchair-using youth. This is extremely important, so clinicians will be able to individually measure physical behavior in wheelchair-using youth with SB. This will support clinicians in developing individually tailored interventions and also evaluate these interventions. In conclusion, wheelchair-using youth with SB are substantially more sedentary and less physically active both in type of activity and intensity compared to typically developing peers.
Comparison between school days and weekend days showed that physical behavior on weekend days was less favorable. The intensity of the different activities varied extensively between the participants, indicating the importance of individually tailored assessments and interventions. Letter to the editor: standardized use of the terms "sedentary" and "sedentary behaviours".
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