RESUMEN
Most people with intellectual disabilities have comorbid health conditions, which will impact optimization of sporting performance. Classification is used in Paralympic events to ensure that those with similar levels of functional ability compete fairly against each other. An evidence-based approach needs to be developed for athletes with intellectual disabilities to be classified in relation to their overall functional capacity into competition groups of similar ability. This research builds on previous work using the taxonomy of The International Classification of Functioning, Disability and Health (ICF) to group athletes with intellectual disabilities into comparable competition groups as an approach to Paralympic classification. Three groups of athletes-Virtus, Special Olympics, and Down syndrome-are compared using the ICF questionnaire indicating functional health status in relation to sporting performance. The questionnaire was found to discriminate between athletes with Down syndrome and other athletes, and an approach to using a cutoff score to develop competition classes is explored.
Asunto(s)
Síndrome de Down , Discapacidad Intelectual , Humanos , Clasificación Internacional del Funcionamiento, de la Discapacidad y de la Salud , Atletas , Estado de SaludRESUMEN
Background and Objectives: Double poling is an important fundamental skill required for cross-country skiing in able-bodied athletes and in those with physical disabilities. Meanwhile, the performance improvement and injury prevention related to double poling requires a thorough assessment, whereas the scapular and shoulder kinematics in different postural conditions remain to be clarified. The main purpose of this study was to evaluate the biomechanics during cross-country ski double poling in the standing and sitting positions. Materials and Methods: Eleven participants underwent kinematic assessments of the shoulder girdle during double poling on a ski ergometer with an electromagnetic tracking device. The cycle rate, stroke length, stroke speed, thorax motion relative to pelvis, scapular motions relative to thorax, humeral motions relative to thorax, and humeral motions relative to scapula were calculated for five double-poling cycles. Results: In the sitting position, the angles of humerothoracic elevation were 18 degrees larger and glenohumeral elevation 13 degrees larger than in the standing position at the upward point and range of motion. Conclusions: The study revealed that double poling in the sitting condition increased the humerothoracic and glenohumeral elevation angle to secure the poling margin. If these are excessive, there is a risk of shoulder injuries such as subacromial impingement.
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Sedestación , Esquí , Fenómenos Biomecánicos , Estudios Transversales , Humanos , Masculino , Esquí/lesiones , Posición de PieRESUMEN
The inherent hydrodynamic resistance force, or passive drag, of a swimmer directly influences how they move through the water. For swimmers with physical impairments, the strength of association between passive drag and swimming performance is unknown. Knowledge on this factor could improve the World Para Swimming classification process. This study established the relationship between passive drag and 100 m freestyle race performance in Para swimmers with physical impairments. Using a cross-sectional study design, an electrical-mechanical towing device was used to measure passive drag force in 132 international-level Para swimmers. There was a strong, negative correlation between normalized passive drag force and 100 m freestyle race speed in the combined participant cohort (ρ = -0.77, p < 0.001). Type of physical impairment was found to affect the relationship between passive drag and 100 m freestyle race speed when included in linear regression (R2 = 0.65, χ2 = 11.5, p = 0.025). These findings contribute to the body of evidence that passive drag can provide an objective assessment of activity limitation in Para swimmers with physical impairments. The effect of physical impairment type on the relationship between passive drag and swimming performance should be accounted for in Para swimming classification.
Asunto(s)
Rendimiento Atlético/fisiología , Deportes para Personas con Discapacidad/clasificación , Deportes para Personas con Discapacidad/fisiología , Natación/fisiología , Adolescente , Adulto , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
This study examined the reliability of instrumented trunk assessment methods across two experiments to develop and improve evidence-based classification in Para swimming. Trunk coordination, range of motion (ROM), and strength were assessed in 38 non-disabled participants. Each test battery was completed on two occasions to determine inter-session reliability. Intra-session reliability was also determined in Experiment Two. Absolute agreement of two-way mixed intraclass correlation coefficients (ICC 3,1) was calculated to assess reliability. Standard errors of measurement (SEMs) were also reported to facilitate comparisons between different outcomes. Trunk coordination measures had low-to-moderate reliability (inter-session ICCs = 0.00-0.60; intra-session ICCs = 0.14-0.65) and variable SEMs (5-60%). Trunk ROM demonstrated moderate-to-excellent reliability (inter-session ICCs = 0.61-0.93; intra-session ICCs = 0.87-0.95) and good SEMs (<10%). Trunk strength measures demonstrated good-to-excellent reliability (ICCs = 0.87-0.98) and good SEMs (<10%). The strength values obtained for the load cell and hand-held dynamometer (HHD) were significantly different from each other with the HHD underestimating strength. Modifications provided in Experiment Two improved the reliability of strength and ROM assessments but did not improve coordination measures. Further research involving para swimmers is required to establish the validity of the methods.
Asunto(s)
Fuerza Muscular/fisiología , Desempeño Psicomotor/fisiología , Rango del Movimiento Articular/fisiología , Natación/fisiología , Torso/fisiología , Adulto , Fenómenos Biomecánicos/fisiología , Voluntarios Sanos , Humanos , Dinamómetro de Fuerza Muscular , Paratletas/clasificación , Reproducibilidad de los Resultados , Sedestación , Columna Vertebral , Deportes para Personas con Discapacidad/clasificación , Deportes para Personas con Discapacidad/fisiología , Natación/clasificación , Adulto JovenRESUMEN
A fundamental aspect of classification systems in Paralympic sport is having valid and reliable measures of impairment. However, minimal consensus exists for assessing impaired strength, coordination and range of motion. This review aimed to systematically identify measures of upper body strength, coordination and range of motion impairments that meet the requirements for use in evidence-based classification systems in wheelchair sports. Three electronic databases were searched from 2003 until 31 August 2019 for studies that assessed upper body function of participants and used a measurement tool that assessed strength, coordination or range of motion. The body of evidence for each identified measure was appraised using the Grading of Recommendations Assessment, Development and Evaluation framework. Twenty-three studies were included: ten measured strength and coordination, and six measured range of motion. There was "moderate" confidence in using isometric strength for assessing strength impairment. Tapping tasks for the assessment of coordination impairment received a "low" confidence rating. All other identified measures of coordination and range of motion impairment received a "very low" confidence rating. Several potential measures were identified for assessing upper body strength, coordination and range of motion impairments. Further research is warranted to investigate their use for classification in Paralympic wheelchair sports.
Asunto(s)
Rendimiento Atlético/clasificación , Evaluación de la Discapacidad , Paratletas/clasificación , Deportes para Personas con Discapacidad/clasificación , Ataxia/clasificación , Ataxia/diagnóstico , Sesgo , Fuerza de la Mano , Humanos , Contracción Isométrica , Fuerza Muscular , Equilibrio Postural , Desempeño Psicomotor , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Natación/fisiología , Silla de RuedasRESUMEN
This study examined the relationship between proximal arm strength and mobility performance in wheelchair rugby (WR) athletes and examined whether a valid structure for classifying proximal arm strength impairment could be determined. Fifty-seven trained WR athletes with strength impaired arms and no trunk function performed six upper body isometric strength tests and three 10 m sprints in their rugby wheelchair. All strength measures correlated with 2 m and 10 m sprint times (r ≥ -0.43; p ≤ 0.0005) and were entered into k-means cluster analyses with 4-clusters (to mirror the current International Wheelchair Rugby Federation [IWRF] system) and 3-clusters. The 3-cluster structure provided a more valid structure than both the 4-cluster and existing IWRF system, as evidenced by clearer differences in strength (Effect sizes [ES] ≥ 1.0) and performance (ES ≥ 1.1) between adjacent clusters and stronger mean silhouette coefficient (0.64). Subsequently, the 3-cluster structure for classifying proximal arm strength impairment would result in less overlap between athletes from adjacent classes and reduce the likelihood of athletes being disadvantaged due to their impairment. This study demonstrated that the current battery of isometric strength tests and cluster analyses could facilitate the evidence-based development of classifying proximal arm strength impairment in WR.
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Brazo/fisiología , Fútbol Americano/fisiología , Movimiento/fisiología , Fuerza Muscular/fisiología , Paratletas , Prueba de Estudio Conceptual , Adulto , Ataxia/clasificación , Ataxia/fisiopatología , Rendimiento Atlético/fisiología , Análisis por Conglomerados , Femenino , Fútbol Americano/clasificación , Humanos , Contracción Isométrica/fisiología , Masculino , Paratletas/clasificación , Valores de Referencia , Traumatismos de la Médula Espinal/complicaciones , Deportes para Personas con Discapacidad/fisiología , Silla de RuedasRESUMEN
The purpose of this study was to examine the interrater reliability of a new evidence-based classification system for Para Va'a. Twelve Para Va'a athletes were classified by three classifier teams each consisting of a medical and a technical classifier. Interrater reliability was assessed by calculating intraclass correlation for the overall class allocation and total scores of trunk, leg, and on-water test batteries and by calculating Fleiss's kappa and percentage of total agreement in the individual tests of each test battery. All classifier teams agreed with the overall class allocation of all athletes, and all three test batteries exhibited excellent interrater reliability. At a test level, agreement between classifiers was almost perfect in 14 tests, substantial in four tests, moderate in four tests, and fair in one test. The results suggest that a Para Va'a athlete can expect to be allocated to the same class regardless of which classifier team conducts the classification.
Asunto(s)
Paratletas , Deportes para Personas con Discapacidad/fisiología , Deportes , Deportes Acuáticos/clasificación , Humanos , Reproducibilidad de los ResultadosRESUMEN
This study aimed to investigate the association between the optimum power load in the bench press (BP), shoulder press (SP), and prone bench pull (PBP) exercises and acceleration (ACC) and speed performances in 11 National Team wheelchair basketball (WB) players with similar levels of disability. All athletes were previously familiarized with the testing procedures that were performed on the same day during the competitive period of the season. First, athletes performed a wheelchair 20-m sprint assessment and, subsequently, a maximum power load test to determine the mean propulsive power (MPP) in the BP, SP, and PBP. A Pearson product-moment correlation was used to examine the relationships between sprint velocity (VEL), ACC, and the MPP in the three exercises. The significance level was set as p < .05. Large to very large significant associations were observed between VEL and ACC and the MPP in the BP, SP, and PBP exercises (r varying from .60 to .77; p < .05). The results reveal that WB players who produce more power in these three exercises are also able to accelerate faster and achieve higher speeds over short distances. Given the key importance of high and successive ACCs during wheelchair game-related maneuvers, it is recommended that coaches frequently assess the optimum power load in BP, SP, and PBP in WB players, even during their regular training sessions.
Asunto(s)
Aceleración , Rendimiento Atlético , Baloncesto , Paratletas , Silla de Ruedas , Adolescente , Adulto , Fenómenos Biomecánicos , Brasil , Femenino , Humanos , MasculinoRESUMEN
The classification system for handcycling groups athletes into five hierarchical classes, based on how much their impairment affects performance. Athletes in class H5, with the least impairments, compete in a kneeling position, while athletes in classes H1 to H4 compete in a recumbent position. This study investigated the average time-trial velocity of athletes in different classes. A total of 1,807 results from 353 athletes who competed at 20 international competitions (2014-2018) were analyzed. Multilevel regression was performed to analyze differences in average velocities between adjacent pairs of classes, while correcting for gender, age, and event distance. The average velocity of adjacent classes was significantly different (p < .01), with higher classes being faster, except for H4 and H5. However, the effect size of the differences between H3 and H4 was smaller (d = 0.12). Hence, results indicated a need for research in evaluating and developing evidence-based classification in handcycling, yielding a class structure with meaningful performance differences between adjacent classes.
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Ciclismo/clasificación , Personas con Discapacidad , Paratletas/clasificación , Adulto , Atletas , Ciclismo/fisiología , Femenino , Humanos , Masculino , Análisis Multinivel , Estudios RetrospectivosRESUMEN
Little is known about the factors influencing Paralympic athletes' journey to expertise and whether these athletes have trajectories similar to those of their able-bodied (AB) peers. The purpose of this project was to compare the developmental trajectories of wheelchair and AB basketball players. A total of 150 participants completed the Developmental History of Athletes Questionnaire. Results revealed that while AB athletes reached early career milestones at a significantly younger age, athletes with congenital impairments reached midcareer milestones at similar ages to AB athletes. In addition, athletes with acquired impairments were able to reach key late-career performance milestones (i.e., national and international debuts) at a similar age to the other two groups. The findings from this study suggest complex developmental pathways that may not be reflected in current developmental models. Therefore, the authors suggest that scientists and practitioners be cognizant of context-specific needs when providing training recommendations.
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Atletas/psicología , Baloncesto , Paratletas/psicología , Deportes para Personas con Discapacidad , Silla de Ruedas , Adolescente , Personas con Discapacidad , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
Initiatives have been designed to attract novice athletes and to enable transfer for experienced athletes. However, the authors have very little knowledge of the effectiveness of these programs. To further improve our understanding, this study explored the demographic and sporting careers of 225 participants attending one of the 10 Paralympian Search events held between 2016 and 2018. The sample consisted of participants with a wide range of impairments and sport experiential backgrounds. The majority of the participants reported having some experience in sports, suggesting that either the promotions reached athletes involved in sports already or the advertising appealed especially to this cohort. Athletes with impairments acquired at various stages of their lives (congenital, before adolescence, adolescence, early adulthood, and adulthood) displayed differences in their sporting trajectories, suggesting considerations for current developmental models. Furthermore, it should be considered to vary the testing locations of future events to increase the reach to rural areas and implement new methods to attract novice participants.
Asunto(s)
Paratletas , Deportes , HumanosRESUMEN
PURPOSE: Although sprinters with unilateral (UTF) and bilateral transfemoral (BTF) amputations and functional impairments (FIs) without amputation were allocated into different classifications because of the recent revision of the International Paralympic Committee Athletics Rules and Regulations, it is unclear whether running mechanics differ among the three groups. The aim of this study was to investigate the differences in the spatiotemporal parameters of the three groups during 100-m sprint in official competitions. METHODS: Using publicly available Internet broadcasts, we analyzed 11 elite-level sprinters with UTF amputation, 4 sprinters with BTF amputation, and 5 sprinters with FI without amputation. The best personal times for nearly all individuals were included. For each sprinter's race, the average speed, step frequency, and step length were calculated using the number of steps in conjunction with the official race time. RESULTS: Although there were no significant differences in the average speed among the UTF, BTF, and FI groups (7.95 ± 0.22, 7.90 ± 0.42, and 7.93 ± 0.14 m/s, respectively, p = 0.87), those with BTF amputation showed significantly lower step frequency (UTF: 4.20 ± 0.20 Hz, BTF: 3.71 ± 0.32 Hz, FI: 4.20 ± 0.10 Hz, p < 0.05) and longer step length (UTF: 1.90 ± 0.08 m, BTF: 2.14 ± 0.02 m, FI: 1.89 ± 0.06 m, p < 0.05) than the other two groups. CONCLUSION: These results suggest that the step characteristics during sprinting are not the same among sprinters with UTF amputation, BTF amputations, or FI without amputations.
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Amputados/clasificación , Rendimiento Atlético , Carrera , Miembros Artificiales , Atletas , Fenómenos Biomecánicos , Humanos , Grabación en VideoRESUMEN
Para Va'a is a new Paralympic sport in which athletes with trunk and/or leg impairment compete over 200 m. The purpose of this study was to examine the impact of impairment on kinematic and kinetic variables during Va'a ergometer paddling. Ten able-bodied and 44 Para Va'a athletes with impairments affecting: trunk and legs (TL), legs bilaterally (BL) or leg unilaterally (UL) participated. Differences in stroke frequency, mean paddling force, and joint angles and correlation of the joint angles with paddling force were examined. Able-bodied demonstrated significantly greater paddling force as well as knee and ankle flexion ranges of movement (ROM) on the top hand paddling side compared to TL, BL and UL. Able-bodied, BL and UL demonstrated greater paddling force and trunk flexion compared to TL, and UL demonstrated larger bottom hand paddling side knee and ankle flexion ROM compared to BL. Significant positive correlations were observed for both male and female athletes between paddling force and all trunk flexion angles and ROM in the trunk and pelvis rotation and bottom hand paddling side hip, knee and ankle flexion. The results of this study are important for creating an evidence-based classification system for Para Va'a.
Asunto(s)
Fenómenos Biomecánicos , Rango del Movimiento Articular , Deportes para Personas con Discapacidad/fisiología , Deportes Acuáticos/fisiología , Adulto , Articulación del Tobillo , Atletas , Ergometría , Femenino , Humanos , Cinética , Articulación de la Rodilla , Masculino , Persona de Mediana Edad , Pelvis , TorsoRESUMEN
This study examined the validity of isometric strength tests for evidence-based classification in Para swimming. Thirty non-disabled participants and forty-two Para swimmers with physical impairment completed an isometric strength test battery designed to explain activity limitation in the freestyle discipline. Measures pertaining to dominant and non-dominant limb strength and symmetry were derived from four strength tests that were found to be reliable in a cohort of non-disabled participants (ICC = 0.85-0.97; CV = 6.4-9.1%). Para swimmers had lower scores in strength tests compared with non-disabled participants (d = 0.14-1.00) and the strength test battery successfully classified 95% of Para swimmers with physical impairment using random forest algorithm. Most of the strength measures had low to moderate correlations (r = 0.32 to 0.53; p ≤ 0.05) with maximal freestyle swim speed in Para swimmers. Although, fewer correlations were found when Para swimmers with hypertonia or impaired muscle power were analysed independently, highlighting the impairment-specific nature of activity limitation in Para swimming. Collectively, the strength test battery has utility in Para swimming classification to infer loss of strength in Para swimmers, guide minimum eligibility criteria, and to define the impact that strength impairment has on Para swimming performance.
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Rendimiento Atlético/fisiología , Evaluación de la Discapacidad , Prueba de Esfuerzo , Fuerza Muscular , Deportes para Personas con Discapacidad/fisiología , Natación/fisiología , Adulto , Atletas/clasificación , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Adulto JovenRESUMEN
Identifying as a regular exerciser has been found to effectively alter stereotypes related to warmth and competence for adults with a physical disability; however, it remains unclear how sport participation can influence this trend. Therefore, this study aimed to examine warmth and competence perceptions of adults with a physical disability portrayed as elite and nonelite athletes relative to other athletic and nonathletic subgroups of adults with and without a physical disability in the context of the stereotype content model. Using survey data from able-bodied participants (N = 302), cluster analyses were applied to a behaviors from intergroup affect and stereotypes map for displaying the intersection of warmth and competence perceptions. The results demonstrated that adults with a physical disability who are described as elite athletes (i.e., Paralympians) are clustered with high warmth and high competence, similar to their able-bodied athletic counterparts (i.e., Olympians). The findings suggest that perceiving athletic and elite sport statuses for adults with a physical disability may counter the stereotypes commonly applied to this group.
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Atletas , Personas con Discapacidad , Estereotipo , Adolescente , Adulto , Anciano , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Trunk, pelvis, and leg movements are important for performance in sprint kayaking. Para-kayaking is a new Paralympic sport in which athletes with trunk and/or leg impairment compete in 3 classification groups. The purpose of this study was to identify how physical impairments impact on performance by examining: differences in 3-dimensional joint range of motion (RM) between 10 (4 females and 6 males) elite able-bodied kayakers and 41 (13 females and 28 males) elite para-kayakers from the 3 classification groups, and which joint angles were correlated with power output during high-intensity kayak ergometer paddling. There were significant differences in RM between the able-bodied kayakers and the 3 para-kayak groups for the shoulders (flexion, rotation: able-bodied kayakers < para-kayakers); trunk and pelvis (rotation: able-bodied kayakers > para-kayakers); and legs (hip, knee, and ankle flexion: able-bodied kayakers > para-kayakers) during paddling. Furthermore, athletes with greater impairment exhibited lower trunk and leg RM compared with those with less impairment. Significant positive correlations were observed for both males and females between power output and peak shoulder and trunk flexion; trunk and pelvis rotation RM; and hip, knee, and ankle flexion RM. This information is important for understanding how key kinematic and kinetic variables for para-kayaking performance vary between athletes from different classification groups.
Asunto(s)
Atletas , Personas con Discapacidad , Fuerza Muscular , Rango del Movimiento Articular , Deportes Acuáticos/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Pierna , Masculino , Rotación , Hombro , Deportes para Personas con Discapacidad , TorsoRESUMEN
The purpose of this study was to gain an understanding of the career development and learning pathways of Paralympic head coaches who previously competed as Paralympic athletes. Each coach participated in a semistructured interview. A thematic analysis of the data revealed three higher order themes, which were called becoming a coach, learning to coach, and lifelong learning and teaching. Across these themes, participants discussed interactions with other coaches and athletes with a disability, learning from mentors and coaching clinics, as well as limited formal educational opportunities they experienced transitioning from athlete to head coach. The findings revealed that they acquired most of their knowledge from a combination of knowledge gained as athletes and informal sources, including trial and error. They also stressed the need for enhanced recruiting of parasport coaches and parasport coach education opportunities that would enhance programs for athletes with physical disabilities, from grassroots to Paralympic levels.
Asunto(s)
Movilidad Laboral , Personas con Discapacidad , Aprendizaje , Tutoría , Mentores , Deportes para Personas con Discapacidad/educación , Adulto , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , EnseñanzaRESUMEN
In cross-country sit-skiing, the trunk plays a crucial role in propulsion generation and balance maintenance. Trunk stability is evaluated by automatic responses to unpredictable perturbations; however, electromyography is challenging. The aim of this study was to identify a measure to group sit-skiers according to their ability to control the trunk. Seated in their competitive sit-ski, 10 male and 5 female Paralympic sit-skiers received 6 forward and 6 backward unpredictable perturbations in random order. k-means clustered trunk position at rest, delay to invert the trunk motion, and trunk range of motion significantly into 2 groups. In conclusion, unpredictable perturbations might quantify trunk impairment and may become an important tool in the development of an evidence-based classification system for cross-country sit-skiers.
RESUMEN
This paper demonstrates how a qualitative methodology can be used to gain novel insights into the demands of wheelchair racing and the impact of particular racing chair configurations on optimal sport performance via engagement with expert users (wheelchair racers, coaches, and manufacturers). We specifically explore how expert users understand how wheels, tires, and bearings impact sport performance and how they engage, implement, or reject evidence-based research pertaining to these components. We identify areas where participants perceive there to be an immediate need for more research especially pertaining to the ability to make individualized recommendations for athletes. The findings from this project speak to the value of a qualitative research design for capturing the embodied knowledge of expert users and also make suggestions for "next step" projects pertaining to wheels, tires, and bearings drawn directly from the comments of participants.
Asunto(s)
Diseño de Equipo , Equipo Deportivo , Deportes para Personas con Discapacidad , Silla de Ruedas , Rendimiento Atlético , Conducta de Elección , Toma de Decisiones , Femenino , Humanos , Entrevistas como Asunto , Masculino , Percepción , Investigación Cualitativa , InvestigaciónRESUMEN
On curves, non-amputees' maximum running speed is slower on smaller radii and thought to be limited by the inside leg's mechanics. Similar speed decreases would be expected for non-amputees in both counterclockwise and clockwise directions because they have symmetric legs. However, sprinters with unilateral leg amputation have asymmetric legs, which may differentially affect curve-running performance and Paralympic competitions. To investigate this and understand the biomechanical basis of curve running, we compared maximum curve-running (radius 17.2 m) performance and stride kinematics of six non-amputee sprinters and 11 sprinters with a transtibial amputation. Subjects performed randomized, counterbalanced trials: two straight, two counterclockwise curves and two clockwise curves. Non-amputees and sprinters with an amputation all ran slower on curves compared with straight running, but with different kinematics. Non-amputees ran 1.9% slower clockwise compared with counterclockwise (P<0.05). Sprinters with an amputation ran 3.9% slower with their affected leg on the inside compared with the outside of the curve (P<0.05). Non-amputees reduced stride length and frequency in both curve directions compared with straight running. Sprinters with an amputation also reduced stride length in both curve-running directions, but reduced stride frequency only on curves with the affected leg on the inside. During curve running, non-amputees and athletes with an amputation had longer contact times with their inside compared with their outside leg, suggesting that the inside leg limits performance. For sprinters with an amputation, the prolonged contact times of the affected versus unaffected leg seem to limit maximum running speed during both straight running and running on curves with the affected leg on the inside.