Evaluating the Validity of Tests to Predict Sprint and Change of Direction Speed in Para-Athletes With Brain Impairments.

Maximum running speed is a performance determinant in para-athletics and cerebral palsy football. Sixty international para-athletes with brain impairments completed five activity-limitation tests (standing broad jump, four bounds for distance, split jumps, 10-m speed skip, and running in place) and two criterion tests (40-m sprint and modified agility test). The same three tests (standing broad jump, four bounds for distance, and 10-m speed skip) that correlated with running performance in nondisabled runners (.67 < r < -.82; p < .05; 75% of variance) also correlated in para-athletes with brain impairments (.41 < r < -.62; p < .01; 55% of variance). Standing broad jump, four bounds for distance, split jumps, and running in place also correlated with change-of-direction speed (.43 < r < -.63; p < .01; 58% of variance). Results indicate that methods of classification for para-athletics with nondisabled runners are also valid with para-athletes with brain impairments, and new sport-specific relationships were found for assessing the performance of rapid and short sprints toward different directions, specific of a team para-sport like cerebral palsy football.

Does sports-specific training improve measures of impairment developed for para sport classification? A multiple-baseline, single-case experiment.

Conceptually, sports-specific training should not influence measures of impairment used to classify Para athletes. This study evaluated the extent to which measures of strength, range of movement and coordination developed for Para swimming classification changed in response to a performance-focused swimming programme. A five-phase multiple-baseline, single-case experimental research design was utilized. Three participants with cerebral palsy and high support needs completed the 64-week study, which included two 16-week performance-focused swimming training blocks. Swimming speed, isometric shoulder extension strength, shoulder flexion range of movement and upper limb coordination were monitored throughout.Interrupted Time-Series Simulation Method analysis demonstrated large, significant changes in swimming speed (m/s) during the first (d = 2.17; 95% CI 0.45-3.88; p = 0.01) and second (d = 2.59; 95% CI 1.66-3.52; p = 0.00) training blocks. In contrast, changes in strength, range of movement and coordination were predominantly trivial and non-significant. This was the first study to investigate training responsiveness of measures developed for Para sport classification. Results indicate that despite significantly improved swimming performance, impairment measures remained relatively stable, and therefore these measures of impairment may be valid for the purposes of Para swimming classification. Further research is required in elite athletes, different sports and different impairment types.

Validity of Two Wheelchair-Mounted Devices for Estimating Wheelchair Speed and Distance Traveled.

This study evaluated the validity of two wheelchair-mounted devices-the Cateye® and Wheeler-for monitoring wheelchair speed and distance traveled. Speed estimates were validated against a calibrated treadmill at speeds from 1.5 to 10 km/hr. Twenty-five wheelchair users completed a course of known distance comprising a sequence of everyday wheelchair activities. Speed estimate validity was very good (mean absolute percentage error ≤ 5%) for the Wheeleri at all speeds and for the Cateye at speeds >3 km/hr but not speeds <3 km/hr (mean absolute percentage error > 20%). Wheeleri distance estimates were good (mean absolute percentage error < 10%) for linear pushing activities and general maneuvering but poor for confined-space maneuvering. Cateye estimates were good for continuous linear propulsion but poor for discontinuous pushing and maneuvering (both general and confined space). Both devices provided valid estimates of speed and distance for typical wheelchair-based exercise activities. However, the Wheeleri provided more accurate estimates of speed and distance during typical everyday wheelchair activities.

Cluster analysis of novel isometric strength measures produces a valid and evidence-based classification structure for wheelchair track racing.

BACKGROUND: The Para athletics wheelchair-racing classification system employs best practice to ensure that classes comprise athletes whose impairments cause a comparable degree of activity limitation. However, decision-making is largely subjective and scientific evidence which reduces this subjectivity is required. AIM: To evaluate whether isometric strength tests were valid for the purposes of classifying wheelchair racers and whether cluster analysis of the strength measures produced a valid classification structure. METHODS: Thirty-two international level, male wheelchair racers from classes T51-54 completed six isometric strength tests evaluating elbow extensors, shoulder flexors, trunk flexors and forearm pronators and two wheelchair performance tests-Top-Speed (0-15 m) and Top-Speed (absolute). Strength tests significantly correlated with wheelchair performance were included in a cluster analysis and the validity of the resulting clusters was assessed. RESULTS: All six strength tests correlated with performance (r=0.54-0.88). Cluster analysis yielded four clusters with reasonable overall structure (mean silhouette coefficient=0.58) and large intercluster strength differences. Six athletes (19%) were allocated to clusters that did not align with their current class. While the mean wheelchair racing performance of the resulting clusters was unequivocally hierarchical, the mean performance of current classes was not, with no difference between current classes T53 and T54. CONCLUSIONS: Cluster analysis of isometric strength tests produced classes comprising athletes who experienced a similar degree of activity limitation. The strength tests reported can provide the basis for a new, more transparent, less subjective wheelchair racing classification system, pending replication of these findings in a larger, representative sample. This paper also provides guidance for development of evidence-based systems in other Para sports.

Relative Age Affects Marathon Performance in Male and Female Athletes.

Marathon runners are ranked in 5-year age groups. However the extent to which 5-year groupings facilitates equitable competition has not been evaluated. The aim of this study was to evaluate the effect of relative age in male and female marathon running. Marathon finishing times for the top ten male (aged 20-69 years) and female athletes (aged 20-64 years) were obtained from the 2013 New York and Chicago marathons. Intra-class and inter-class validity were evaluated by comparing performances within (intra-class) and between (inter-class) the 5-year age groups. Results showed intra-class effects in all male age groups over 50 years, in all female age groups over 40 years, and in male and female 20-24 age groups (p < 0.05). Inter-class differences existed between the 20-24 and 25-29 age groups in both males and females, between all male age groups over 50 years, and between all female age groups over 40 years (p < 0.05). This study provided the first evaluation of the effects of relative age in male and female marathon running. The results provide preliminary but compelling evidence that the relatively older male athletes in age groups over 50 years and the relatively older females in age groups over 40 years are competitively disadvantaged compared to the younger athletes in these age groups. Key pointsResults showed a curvilinear relationship between age and marathon running performance with the negative effect of age becoming more pronounced in older runners.Relative age effects were found in all age groups over age 50 years in males and over age 40 years in females indicating that the relatively older runners were competitively disadvantaged compared to the relatively younger runners in these age groups.Relative age affected the 20-24 age classification which is consistent with the hypothesis that marathon performance improves until peak performance occurs in the 25-29 age classification.

Dietary Patterns of Competitive Swimmers with Moderate-to-Severe Cerebral Palsy: A 3-Year Longitudinal Evaluation.

AIM: To evaluate the longitudinal dietary patterns of three adolescents with moderate-to-severe cerebral palsy (CP) participating in a performance-focused swimming training intervention. METHOD: Participants were three previously inactive adolescents with CP (15-16 years, GMFCS IV) who had recently (<6 months) enrolled in a swimming training program. Diet quality from diet histories was calculated at 10-time points over 3.25 years using the Dietary Guidelines Index for Children and Adolescents (DGI-CA) and the Healthy Eating Index for Australian Adults (HEIFA-2013). A food group analysis was compared to the Australian Guide to Healthy Eating recommendations. Trends were considered in the context of dietary advice given and the training load. RESULTS: Longitudinal diet quality scores were consistent and ranged from 40 to 76 (DGI-CA) and 33 to 79 (HEIFA-2013). Food group intake remained stable; participants rarely met the recommendations for fruit, vegetables, dairy, grain, and meat but frequently achieved discretionary serves. CONCLUSIONS: Participants with moderate-to-severe CP who were enrolled in a performance-focused swimming training intervention and were monitored frequently maintained diet quality throughout a period where it conventionally declined. Scores were higher than the general population and were maintained irrespective of the training load. Participants frequently met food group recommendations for discretionary foods and were comparable to the general population for other food groups.

Bicycling and Tricycling Road Race Performance in International Para-Cycling Events Between 2011 and 2019.

ABSTRACT: This study described bicycling (C classes) and tricycling (T classes) performance in the International Cycling Federation road race events between 2011 and 2019. A total of 3243 race results from 33 events were analyzed. Race velocity was calculated for each result. Bicycling and tricycling data were separately modeled using a linear mixed-effects model. Bicycling velocity was statistically different between all adjacent men's classes (Cohen d = 0.14-0.73) and between the women's C1 and C2 (d = 1.15) and C3 and C4 (d = 0.48) classes. The absence of statistical differences between some women's bicycling classes may be due to a limited number of observations in these classifications. As expected, velocity was statistically different between men's (d = 1.64) and women's (d = 1.38) T1 and T2 classes. Road race performance was hierarchical within the disciplines of bicycling and tricycling, although not all adjacent women's bicycling classes were statistically different. The existence of a performance hierarchy does not necessarily validate the classification system. The integration of information regarding athlete impairment type and severity, with performance data, would provide greater insight into the validity of the classification system and should be prioritized as an area of future research.

Evaluation of a physical activity promotion intervention for adults with whiplash associated disorders: a single-case experimental design study.

PURPOSE: There is considerable variation in the physical and psychological presentations of people with whiplash-associated disorder (WAD). Optimal treatment continues to be a challenge. This research evaluated the efficacy of a community-located, theory-based intervention designed to promote physically active behaviour in people with persistent WAD, and thereby improve perceptions of pain interference and confidence completing activities in the presence of neck pain. MATERIALS AND METHODS: A multiple-baseline, single-case experimental design was used to evaluate the 16-week intervention across six participants. RESULTS: Weighted Tau-U showed significantly increased accelerometer-measured physical activity in three participants with large effect sizes (>0.5), with increased confidence in one participant (ES > 0.5), and reduced pain interference in another participant (ES > 0.7). Changes in other behaviours included clinically important improvements in quality of life for five participants and, in those participants with baseline symptom levels outside threshold levels, improvements in pain catastrophizing and pain self-efficacy. CONCLUSIONS: Participation in a theory-based intervention resulted in significant improvements in physical and psychological health for five of six participants. Providing this type of community-located physical activity promotion strategy, to individuals with persistent WAD, may help address physical impairments and psychological distress commonly experienced in WAD. Trial registration: The trial was registered with the Australia and New Zealand Clinical Trials Registry (ACTRN: ACTRN12617001261303p) and ClinicalTrials.gov (Protocol Number: 2018000349/2017/743).Implications for rehabilitationRehabilitation professionals should consider recommending theory-based physical activity promotion strategies to reduce physical impairments and psychological distress in individuals with persistent WAD.Individually tailored physical activity promotion strategies may help individuals with persistent WAD become more physically active thereby reducing their risk of diseases associated with inactivity which may compound the effects of WADImprovements in physical and psychological health may occur independently of increasing habitual physical activity.Rehabilitation professionals may find that other community-located strategies which aim to promote physically active behaviour confer similar benefits for individuals with persistent WAD.

Measurement of habitual physical activity performance in adolescents with cerebral palsy: a systematic review.

AIM: This systematic review compares the validity, reliability, and clinical use of habitual physical activity (HPA) performance measures in adolescents with cerebral palsy (CP). METHOD: Measures of HPA across Gross Motor Function Classification System (GMFCS) levels I-V for adolescents (10-18 y) with CP were included if at least 60% of items reported HPA performance in the domains of intensity, frequency, duration, and mode. RESULTS: Seven measures of HPA performance met the criteria: StepWatch, pedometers, Uptimer, heart rate flex method, accelerometers, and self-report measures including the Children's Activity Participation and Enjoyment (CAPE) scale and the Physical Activity Questionnaire for Adolescents. The CAPE scale had the strongest validity and reliability but was limited by its inability to measure activity intensity. No study was identified that evaluated the psychometric properties of physical activity measures in non-ambulant adolescents with CP (GMFCS levels IV and V). INTERPRETATION: When deciding on an appropriate measure of HPA in adolescents with CP, clinicians need to consider their research question including the domains of HPA they are evaluating and the population they wish to assess. Accelerometers provide the most robust information about the patterns of HPA, with some evidence of validity but limited data on reliability. Further research is needed to compare the use of tri- and uniaxial accelerometers.

Validity of accelerometry in ambulatory children and adolescents with cerebral palsy.

To evaluate the validity of the ActiGraph accelerometer for the measurement of physical activity intensity in children and adolescents with cerebral palsy (CP) using oxygen uptake (VO(2)) as the criterion measure. Thirty children and adolescents with CP (mean age 12.6 ± 2.0 years) wore an ActiGraph 7164 and a Cosmed K4b(2) portable indirect calorimeter during four activities; quiet sitting, comfortable paced walking, brisk paced walking and fast paced walking. VO(2) was converted to METs and activity energy expenditure and classified as sedentary, light or moderate-to-vigorous intensity according to the conventions for children. Mean ActiGraph counts min(-1) were classified as sedentary, light or moderate-to-vigorous (MVPA) intensity using four different sets of cut-points. VO(2) and counts min(-1) increased significantly with increases in walking speed (P < 0.001). Receiver operating characteristic (ROC) curve analysis indicated that, of the four sets of cut-points evaluated, the Evenson et al. (J Sports Sci 26(14):1557-1565, 2008) cut-points had the highest classification accuracy for sedentary (92%) and MVPA (91%), as well as the second highest classification accuracy for light intensity physical activity (67%). A ROC curve analysis of data from our participants yielded a CP-specific cut-point for MVPA that was lower than the Evenson cut-point (2,012 vs. 2,296 counts min(-1)), however, the difference in classification accuracy was not statistically significant 94% (95% CI = 88.2-97.7%) vs. 91% (95% CI = 83.5-96.5%). In conclusion, among children and adolescents with CP, the ActiGraph is able to differentiate between different intensities of walking. The use of the Evenson cut-points will permit the estimation of time spent in MVPA and allows comparisons to be made between activity measured in typically developing adolescents and adolescents with CP.

Is increased residual shank length a competitive advantage for elite transtibial amputee long jumpers?

The purpose of this study was to evaluate the extent to which residual shank length affects long jump performance of elite athletes with a unilateral transtibial amputation. Sixteen elite, male, long jumpers with a transtibial amputation were videoed while competing in major championships (World Championships 1998, 2002 and Paralympic Games, 2004). The approach, take-off, and landing of each athlete's best jump was digitized to determine residual and intact shank lengths, jump distance, and horizontal and vertical velocity of center of mass at touchdown. Residual shank length ranged from 15 cm to 38 cm. There were weak, nonsignificant relationships between residual shank length and (a) distance jumped (r = 0.30), (b) horizontal velocity (r = 0.31), and vertical velocity (r = 0.05). Based on these results, residual shank length is not an important determinant of long jump performance, and it is therefore appropriate that all long jumpers with transtibial amputation compete in the same class. The relationship between residual shank length and key performance variables was stronger among athletes that jumped off their prosthetic leg (N = 5), and although this result must be interpreted cautiously, it indicates the need for further research.

Differentiating maximal and submaximal voluntary strength measures for the purposes of medico-legal assessments and para sport classification: A systematic review.

Measurement of maximum voluntary muscle contractions are effort-dependent - valid measurement requires maximal voluntary effort (MVE) from participants. Submaximal efforts (SMEs) yield invalid and potentially misleading results. This is particularly problematic in medico-legal and Para sport assessments where low strength scores may confer a personal advantage. Therefore, objective methods for accurately differentiating MVE and SME are required. This systematic review aimed to identify, appraise and synthesise evidence from scientific studies evaluating the validity of objective methods for differentiating MVE from SME during maximal voluntary contractions. Four electronic databases were searched for original research articles published in English and secondary references appraised for relevance yielding 25 studies for review. Methods were categorised based on eight distinct underlying theories. For isokinetic strength assessment, methods based on two theories - Strength-measure Ratios and Inter-Trial Strength Consistency - correctly classified 100% MVE and > 92% SME. Consequently, research evaluating the relative suitability of these methods for translation into practice is warranted. During isometric strength assessments, methods based on Deceptive Visual Feedback and Force-length properties warrant further investigation. Both methods yielded statistically significant differences between MVE and SME, with minimal overlap in values, but their sensitivity and specificity have not been evaluated.

Validity of the Apple Watch® for monitoring push counts in people using manual wheelchairs.

Objective: A recent Apple Watch® activity-monitoring innovation permits manual wheelchair users to monitor daily push counts. This study evaluated the validity of the Apple Watch® push count estimate.Design: Criterion validity.Setting: Southern Finland and Southeast Queensland, Australia.Participants: Twenty-six manual wheelchair users from Finland and Australia were filmed completing a standardized battery of activities while wearing the Apple Watch® (dominant wrist).Outcome Measures: Wheelchair pushes as determined by the Apple Watch® were compared to directly observed pushes.Results: Agreement between Apple Watch® push counts and directly observed pushes was evaluated using Intraclass correlation coefficients (ICC), Pearson correlations and Bland-Altman analyses. Apple Watch® pushes and directly observed push counts were strongly correlated (ICC = 0.77, P < 0.01) (r = 0.84, P < 0.01). Bland Altman plots indicated that the Apple Watch® underestimated push counts (M = -103; 95% ULoA = 217; LLoA = -423 pushes). Mean absolute percentage error was 13.5% which is comparable to studies evaluating agreement between pedometer-based step counts and directly observed steps.Conclusion: Apple Watch® push-count estimates are acceptable for personal, self-monitoring purposes and for research entailing group-level analyses, but less acceptable where accurate push-count measures for an individual is required.

A prospective, longitudinal study of growth, nutrition and sedentary behaviour in young children with cerebral palsy.

BACKGROUND: Cerebral palsy is the most common cause of physical disability in childhood, occurring in one in 500 children. It is caused by a static brain lesion in the neonatal period leading to a range of activity limitations. Oral motor and swallowing dysfunction, poor nutritional status and poor growth are reported frequently in young children with cerebral palsy and may impact detrimentally on physical and cognitive development, health care utilisation, participation and quality of life in later childhood. The impact of modifiable factors (dietary intake and physical activity) on growth, nutritional status, and body composition (taking into account motor severity) in this population is poorly understood. This study aims to investigate the relationship between a range of factors - linear growth, body composition, oral motor and feeding dysfunction, dietary intake, and time spent sedentary (adjusting for motor severity) - and health outcomes, health care utilisation, participation and quality of life in young children with cerebral palsy (from corrected age of 18 months to 5 years). DESIGN/METHODS: This prospective, longitudinal, population-based study aims to recruit a total of 240 young children with cerebral palsy born in Queensland, Australia between 1st September 2006 and 31st December 2009 (80 from each birth year). Data collection will occur at three time points for each child: 17 - 25 months corrected age, 36 +/- 1 months and 60 +/- 1 months. Outcomes to be assessed include linear growth, body weight, body composition, dietary intake, oral motor function and feeding ability, time spent sedentary, participation, medical resource use and quality of life. DISCUSSION: This protocol describes a study that will provide the first longitudinal description of the relationship between functional attainment and modifiable lifestyle factors (dietary intake and habitual time spent sedentary) and their impact on the growth, body composition and nutritional status of young children with cerebral palsy across all levels of functional ability.

Biomechanics of starting, sprinting and submaximal running in athletes with brain impairment: A systematic review.

OBJECTIVES: Para athletes with brain impairment are affected by hypertonia, ataxia and athetosis, which adversely affect starting, sprinting and submaximal running. The aim was to identify and synthesise evidence from studies that have compared the biomechanics of runners with brain impairments (RBI) and non-disabled runners (NDR). DESIGN: Systematic review. METHODS: Five journal databases were systematically searched from inception to March 2020. Included studies compared the biomechanics of RBI (aged>14 years) and NDR performing either block-starts, sprinting, or submaximal running. RESULTS: Eight studies were included, analysing a total of 100 RBI (78M:22F; 18-38 years) diagnosed with either cerebral palsy (n=44) or traumatic brain injury (n=56). Studies analysed block-starts (n=3), overground sprinting (n=3) and submaximal running (n=2), and submaximal treadmill running (n=1). Horizontal velocity during starts, sprinting and self-selected submaximal speeds were lower in RBI. During sprinting and submaximal running, compared with NDR, RBI had shorter stride length, step length, and flight time, increased ground-contact time, increased cadence, and reduced ankle and hip range of motion. In submaximal running, RBI had decreased ankle-power generation at toe-off. CONCLUSIONS: There is limited research and small sample sizes in this area. However, preliminary evidence suggests that RBI had lower sprint speeds and biomechanical characteristics typical of submaximal running speeds in NDR, including increased ground-contact times and reduced stride length, step length, and flight times. Meaningful interpretation of biomechanical findings in RBI is impeded by impairment variability (type, severity and distribution), and methods which permit valid, reliable impairment stratification in larger samples are required.

Evaluation of a novel intervention to improve physical activity for adults with whiplash associated disorders: Protocol for a multiple-baseline, single case experimental study.

Half of individuals with a whiplash injury experience ongoing pain and disability. Many are insufficiently active for good health, increasing their risk of preventable morbidity and mortality, and compounding the effects of the whiplash injury. This paper describes a protocol for evaluating the efficacy of a physical activity promotion intervention in adults with whiplash associated disorders. A multiple-baseline, single case experimental design will be used to evaluate the effects of a physical activity (PA) intervention that includes evidence-based behaviour change activities and relapse prevention strategies for six adults with chronic whiplash. A structured visual analysis supplemented with statistical analysis will be used to analyse: accelerometer-measured PA, confidence completing PA in the presence of neck pain, and pain interference.