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1.
J Sports Sci ; 38(20): 2314-2320, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32965184

RESUMO

This study was designated to investigate the kinematical differences between successful and faulty spikes, in order to identify the best strategies leading to better spike performance. Simulating a real-game condition, 13 elite youth attackers performed 6 spikes in the presence of 2 blocks. The kinematic variables of the spike performances were recorded using 6 optoelectronic cameras (Vicon Motion systems, Oxford, UK). The paired sample t-test was used to compare the kinematic variables recorded during the delivery of successful and faulty spikes. Among the successful trials, both the angular velocities of the knees (≈12.4%) and hips (≈13.3%), and the vertical velocity of the centre of mass at take-off (≈6.5%) and arm swing (≈8.2%) were considerably higher during the plant phase. Consequently, the jump (≈4.3%) and spike (≈1.5%) heights, as well as the wrist velocity (≈5.5%), were significantly higher during the jump phase of successful spikes. In successful spike performances, the attackers adopted higher hip and knee angular velocities, combined with efficient arm swings, to produce higher take-off velocities and reach higher jump heights. This approach provides them with the better position regarding the ball and the blockers to find the best path and hit the ball with higher arm velocities.


Assuntos
Destreza Motora/fisiologia , Voleibol/fisiologia , Adolescente , Braço/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Cotovelo/fisiologia , Quadril/fisiologia , Humanos , Joelho/fisiologia , Ombro/fisiologia , Estudos de Tempo e Movimento , Punho/fisiologia
2.
Phys Ther ; 100(10): 1825-1851, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32949239

RESUMO

OBJECTIVE: Children with developmental coordination disorder (DCD) are reported to have lower levels of strength and anaerobic capacity. The purpose of this study was to (1) identify field-based tests for strength and anaerobic capacity used in studies comparing children with DCD and children who were typically developing (TD), (2) examine the methodological quality of studies reporting psychometric properties and rate the psychometric properties of the examined test, and (3) summarize available evidence by combining the methodological quality of the studies and the quality of the psychometric properties of the test. METHODS: An electronic search was conducted in July 2019 in 4 electronic databases. For purpose 1, primary studies were included with no exclusion of study design in which children aged 4 to 18 years with DCD were compared with children who were TD on strength and/or anaerobic capacity measures. For purpose 2, primary studies were included with no exclusion of study design in which a psychometric property was investigated. The Consensus-Based Standards for Selection of Health Measurement Instruments (COSMIN) was used to evaluate the methodological quality of the 34 studies and rate the psychometric properties of the tests used. RESULTS: Hand-held dynamometer, bent knee push-up, vertical jump, standing long-jump, functional strength measurement, fitness test, and test battery can be recommended for TD, and the shuttle run item of the Bruininks-Oseretsky Test of Motor Proficiency-Second Edition and 10 m × 5 m sprints (straight and slalom) can be recommended for DCD. CONCLUSION: Information regarding psychometric properties of field-based tests for strength and anaerobic capacity in children with DCD is lacking. IMPACT: Information about the psychometric properties of field-based tests for strength and anaerobic capacity in children with DCD is lacking. More information is available on TD children, but it is also not complete; information regarding validity and responsiveness, especially, is missing. When using measures in children with DCD, it is important to keep in mind this lack of evidence for the validity and reliability of the outcomes for this target group.


Assuntos
Desenvolvimento Infantil , Transtornos das Habilidades Motoras/reabilitação , Destreza Motora/fisiologia , Força Muscular/fisiologia , Aptidão Física/fisiologia , Criança , Feminino , Humanos , Masculino , Atividade Motora/fisiologia , Transtornos das Habilidades Motoras/fisiopatologia , Resistência Física
3.
PLoS One ; 15(8): e0237919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841268

RESUMO

BACKGROUND: Fundamental Movement Skills (FMS) play a critical role in ontogenesis. Many children have insufficient FMS, highlighting the need for universal screening in schools. There are many observational FMS assessment tools, but their psychometric properties are not readily accessible. A systematic review was therefore undertaken to compile evidence of the validity and reliability of observational FMS assessments, to evaluate their suitability for screening. METHODS: A pre-search of 'fundamental movement skills' OR 'fundamental motor skills' in seven online databases (PubMed, Ovid MEDLINE, Ovid Embase, EBSCO CINAHL, EBSCO SPORTDiscus, Ovid PsycINFO and Web of Science) identified 24 assessment tools for school-aged children that: (i) assess FMS; (ii) measure actual motor competence and (iii) evaluate performance on a standard battery of tasks. Studies were subsequently identified that: (a) used these tools; (b) quantified validity or reliability and (c) sampled school-aged children. Study quality was assessed using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklists. RESULTS: Ninety studies were included following the screening of 1863 articles. Twenty-one assessment tools had limited or no evidence to support their psychometric properties. The Test of Gross Motor Development (TGMD, n = 34) and the Movement Assessment Battery for Children (MABC, n = 37) were the most researched tools. Studies consistently reported good evidence for validity, reliability for the TGMD, whilst only 64% of studies reported similarly promising results for the MABC. Twelve studies found good evidence for the reliability and validity of the Bruininks-Oseretsky Test of Motor Proficiency but poor study quality appeared to inflate results. Considering all assessment tools, those with promising psychometric properties often measured limited aspects of validity/reliability, and/or had limited feasibility for large scale deployment in a school-setting. CONCLUSION: There is insufficient evidence to justify the use of any observational FMS assessment tools for universal screening in schools, in their current form.


Assuntos
Destreza Motora/fisiologia , Movimento/fisiologia , Psicometria/métodos , Instituições Acadêmicas , Criança , Humanos , Reprodutibilidade dos Testes
4.
PLoS One ; 15(8): e0221668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776927

RESUMO

BACKGROUND: Animal models of brain recovery identify the first days after lesioning as a time of great flux in sensorimotor function and physiology. After rodent motor system lesioning, daily skill training in the less affected forelimb reduces skill acquisition in the more affected forelimb. We asked whether spontaneous human motor behaviors of the less affected upper extremity (UE) early after stroke resemble the animal training model, with the potential to suppress clinical recovery. METHODS: This prospective observational study used a convenience sample of patients (n = 25, mean 4.5 ±1.8) days after stroke with a wide severity range; Controls were hospitalized for non-neurological conditions (n = 12). Outcome measures were Accelerometry, Upper-Extremity Fugl-Meyer (UEFM), Action Research Arm Test (ARAT), Shoulder Abduction/ Finger Extension Test (SAFE), NIH Stroke Scale (NIHSS). RESULTS: Accelerometry indicated total paretic UE movement was reduced compared to controls, primarily due to a 44% reduction of bilateral UE use. Unilateral paretic movement was unchanged. Thus, movement shifted early after stroke; bilateral use was reduced and unilateral use of the non-paretic UE was increased by 77%. Low correlations between movement time and motor performance prompted an exploratory factor analysis (EFA) revealing a 2-component solution; motor performance tests load on one component (motor performance) whereas accelerometry-derived variables load on a second orthogonal component (quantity of movement). CONCLUSIONS: Early after stroke, spontaneous overall UE movement is reduced, and movement shifts to unilateral use of the non-paretic UE. Two mechanisms that could influence motor recovery may already be in place 4.5 ± 1.8 days post stroke: (1) the overuse of the less affected UE, which could set the stage for learned non-use and (2) skill acquisition in the non-paretic limb that could impede recovery. Accurate UE motor assessment requires two independent constructs: motor performance and quantity of movement. These findings provide opportunities and measurement methods for studies to develop new behaviorally-based stroke recovery treatments that begin early after onset.


Assuntos
Atividade Motora/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Acelerometria/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Destreza Motora/fisiologia , Movimento/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Paresia/fisiopatologia , Paresia/terapia , Estudos Prospectivos , Recuperação de Função Fisiológica/fisiologia , Fatores de Tempo , Estados Unidos , Extremidade Superior/fisiologia
5.
Neuron ; 107(3): 580-589.e6, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32778224

RESUMO

To induce brain plasticity in humans, we casted the dominant upper extremity for 2 weeks and tracked changes in functional connectivity using daily 30-min scans of resting-state functional MRI (rs-fMRI). Casting caused cortical and cerebellar regions controlling the disused extremity to functionally disconnect from the rest of the somatomotor system, while internal connectivity within the disused sub-circuit was maintained. Functional disconnection was evident within 48 h, progressed throughout the cast period, and reversed after cast removal. During the cast period, large, spontaneous pulses of activity propagated through the disused somatomotor sub-circuit. The adult brain seems to rely on regular use to maintain its functional architecture. Disuse-driven spontaneous activity pulses may help preserve functionally disconnected sub-circuits.


Assuntos
Córtex Motor/diagnóstico por imagem , Plasticidade Neuronal/fisiologia , Restrição Física , Atividades Cotidianas , Moldes Cirúrgicos , Feminino , Lateralidade Funcional , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/fisiologia , Destreza Motora/fisiologia , Força Muscular/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Extremidade Superior
6.
PLoS One ; 15(8): e0238197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841286

RESUMO

The aim of this study was to compare artistic swimmers (ASs) and water polo players (WPs) in their polyrhythmic production ability and entrainment between arm and leg motion frequency. Nine ASs and nine WPs participated in the study. First, we assessed the natural eggbeater kick frequency of each participant without any additional motion for 20 s. We then required the participants to perform a circular arm movement in synchronization with two sequences of metronome rhythms (either 100%, 80% and 120% or100%, 120% and 80% of their natural eggbeater kick frequency) while maintaining their natural eggbeater kick frequency. All tasks were repeated three times. The participants' performances were recorded by a motion capture system synchronized with the metronome. A two-way mixed-design ANOVA was performed on the coefficient of variation of natural eggbeater kick frequency obtained from the first task to confirm the consistency of participants' kicking motion. In the second task, a three-way mixed-design ANOVA was performed on the average frequency of the arm and leg motions to assess the entrainment between the two. In the first task, there were no significant main effects and interaction between group and trial in the coefficient of variation of eggbeater kick frequency, suggesting that both WPs and ASs maintained their natural eggbeater kick frequency equally consistently. In the second task, however, WPs were not able to maintain their natural eggbeater kick frequency when they were required to do circular arm movements at 120% tempo (p < .01). On the other hand, ASs successfully maintained their natural eggbeater kick frequency with all metronome rhythms, suggesting that they have a better polyrhythmic production ability than WPs.


Assuntos
Música , Natação/fisiologia , Esportes Aquáticos/fisiologia , Adolescente , Adulto , Braço/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Destreza Motora/fisiologia , Movimento/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto Jovem
7.
J Sports Sci ; 38(17): 1975-1983, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32654588

RESUMO

This paper examined effects of two interventions on cardiorespiratory fitness and motor skills, and whether these effects are influenced by baseline levels, and dose of moderate-to-vigorous physical activity (MVPA) during the intervention. A cluster randomized controlled trial was implemented in 22 schools (n = 891; 9.2 ± 07 years). Intervention groups received aerobic or cognitively engaging exercise (14-weeks, four lessons per week). Control groups followed their regular physical education programme. Cardiorespiratory fitness, motor skills and MVPA were assessed. Multilevel analysis showed no main effects on cardiorespiratory fitness and motor skills although the amount of MVPA was higher in the aerobic than in the cognitively engaging and control group. Intervention effects did not depend on baseline cardiorespiratory fitness and motor skills. Children with a higher dose of MVPA within the intervention groups had better cardiorespiratory fitness after both interventions and better motor skills after the cognitively engaging intervention. In conclusion, the interventions were not effective to enhance cardiorespiratory fitness and motor skills at a group level, possibly due to large individual differences and to a total dose of MVPA too low to find effects. However, the amount of MVPA is an important factor that influence the effectiveness of interventions.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Aptidão Cardiorrespiratória/psicologia , Cognição/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Destreza Motora/fisiologia , Criança , Feminino , Humanos , Masculino , Países Baixos , Educação Física e Treinamento/métodos , Instituições Acadêmicas , Fatores de Tempo
8.
PLoS One ; 15(7): e0236254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687520

RESUMO

Muscle activity changes quantitatively and temporally during the motor learning process. However, the association between variability in muscle electrical activity and the learning and performance of dexterous hand movements is not well understood. Therefore, we undertook this study to investigate the relationships between temporal and quantitative variabilities in muscle activity and the learning of motor skills. Thirty-eight healthy participants performed 30 trials of a task that measured the time taken to rotate two cork balls 20 times using their non-dominant hand. The electromyographic (EMG) activities of the abductor pollicis brevis (APB), first dorsal interosseous, and extensor digitorum (ED) muscles were recorded. Temporal and quantitative variabilities in the EMG activity were evaluated by calculating the coefficient of variation of the duration and area of EMG activation. As motor learning proceeded, the task was completed more quickly and the EMG variability decreased. For all three muscles, significant correlations were observed between individual participants' ball rotation time and EMG variability. Furthermore, significant positive correlations were observed between improvement in ball rotation time and reduction in EMG variability for the APB and ED muscles. These novel findings provide important insights regarding the relationships between temporal and quantitative variabilities in muscle activity and the learning of fine motor skills.


Assuntos
Variação Biológica Individual , Mãos/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia , Feminino , Humanos , Masculino , Movimento/fisiologia , Contração Muscular/fisiologia , Fatores de Tempo , Adulto Jovem
9.
J Sports Sci ; 38(20): 2367-2373, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32608344

RESUMO

The lateral tilt of the arms accompanied by trunk lateral tilt is a typical blocking manoeuvre in volleyball. However, during this unanticipated blocking movement, an associated risk of ACL injury may result. The aim of the present study was to compare associative ACL risk factors at the initial contact and the first and second peak of VGRF during an unanticipated blocking movement with different arm positions. Synchronized kinematic and kinetic data were collected for each trial of each condition. Student paired t-tests and effect size were used to determine differences between two conditions (S - with arms straight up from the body) and (T - with the arms and trunk laterally tilted). The results showed that the T condition significantly decreases knee flexion, increases VGRF at the foot contact, first peak force and increases the valgus moment at the first peak force. The values of the associated risk factors for a non-contact ACL injury appear to be related to the tilted arm position accompanied by trunk tilt towards to right lower limb during landing. The players should be taught to land with greater knee flexion and, if possible, a double-leg landing to decrease right lower limb loading during the blocking manoeuvre.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Movimento/fisiologia , Voleibol/fisiologia , Adolescente , Braço/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Cinética , Joelho/fisiologia , Tutoria , Destreza Motora/fisiologia , Condicionamento Físico Humano/fisiologia , Fatores de Risco , Estudos de Tempo e Movimento , Tronco/fisiologia
10.
J Sports Sci ; 38(11-12): 1432-1440, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32627682

RESUMO

We study the developmental and professional activities engaged in by 86 female adult soccer players from the senior national teams of Australia, Canada, England, Sweden, and the United States of America. Players completed the Participation History Questionnaire (PHQ) to elicit the amount and type of activities engaged in across their developmental and professional years, including milestones, soccer-specific activity and engagement in other sport activity. Greater specialisation than diversification characterised their childhood developmental activities, including all players starting in soccer in childhood and accumulating more hours in soccer activity than other sports during this period. However, interindividual variation further characterised these childhood activities, with a proportion of players diversifying into other sports and/or soccer play to a greater or lesser degree during childhood when compared to the other players. The amount of coach-led soccer practice increased for all players across their development culminating in an average of 15-16 h/wk across a 40-week season in early adulthood. In contrast, the amount of engagement in other sports and soccer peer-led play varied between players but generally decreased across adolescence to negligible amounts in late adolescence. Findings are commensurate with the deliberate practice framework and early engagement.


Assuntos
Aptidão , Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Destreza Motora/fisiologia , Futebol/fisiologia , Adulto , Austrália , Canadá , Inglaterra , Feminino , Humanos , Condicionamento Físico Humano , Especialização , Suécia , Estados Unidos
11.
BMC Neurol ; 20(1): 243, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532249

RESUMO

BACKGROUND: Cerebral palsy (CP), which is the leading cause of motor disability during childhood, can produce sensory and cognitive impairments at different degrees. Most recent therapeutic interventions for these patients have solely focused on upper extremities (UE), although more than 60% of these patients present lower extremities (LE) deficits. Recently, a new therapeutic concept, Hand-arm Bimanual Intensive Therapy Including Lower Extremities (HABIT-ILE), has been proposed, involving the constant stimulation of UE and LE. Based on motor skill learning principles, HABIT-ILE is delivered in a day-camp setting, promoting voluntary movements for several hours per day during 10 consecutive week days. Interestingly, the effects of this intervention in a large scale of youngsters are yet to be observed. This is of interest due to the lack of knowledge on functional, neuroplastic and biomechanical changes in infants with bilateral CP. The aim of this randomized controlled study is to assess the effects of HABIT-ILE adapted for pre-school children with bilateral CP regarding functional, neuroplastic and biomechanical factors. METHODS: This international, multicentric study will include 50 pre-school children with CP from 12 to 60 months of age, comparing the effect of 50 h (2 weeks) of HABIT-ILE versus regular motor activity and/or customary rehabilitation. HABIT-ILE presents structured activities and functional tasks with continuous increase in difficulty while the child evolves. Assessments will be performed at 3 period times: baseline, two weeks later and 3 months later. The primary outcome will be the Gross Motor Function Measure 66. Secondary outcomes will include Both Hands Assessment, Melbourne Assessment-2, Semmes-Weinstein Monofilament Test, algometry assessments, executive function tests, ACTIVLIM-CP questionnaire, Pediatric Evaluation of Disability Inventory (computer adaptative test), Young Children's Participation and Environment Measure, Measure of the Process of Care, Canadian Occupational Performance Measure, neuroimaging and kinematics. DISCUSSION: The results of this study should highlight the impact of a motor, intensive, goal-directed therapy (HABIT-ILE) in pre-school children at a functional, neuroplastic and biomechanical level. In addition, this changes could demonstrated the impact of this intervention in the developmental curve of each child, improving functional ability, activity and participation in short-, mid- and long-term. NAME OF THE REGISTRY: Evaluation of Functional, Neuroplastic and Biomechanical Changes Induced by an Intensive, Playful Early-morning Treatment Including Lower Limbs (EARLY-HABIT-ILE) in Preschool Children With Uni and Bilateral Cerebral Palsy (HABIT-ILE). TRIAL REGISTRATION: NCT04017871 REGISTRATION DATE: July 12, 2019.


Assuntos
Paralisia Cerebral/reabilitação , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Canadá , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Extremidade Inferior/fisiopatologia , Masculino , Destreza Motora/fisiologia , Estudos Multicêntricos como Assunto , Extremidade Superior/fisiopatologia
12.
J Sports Sci ; 38(17): 1984-1996, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32573357

RESUMO

Previous studies investigating the relationship between motor skill, physical activity and fitness in children have not thoroughly considered the role of self-perception. Therefore, the study aim was to test a theoretical framework, which considered both actual and perceived motor skill as well as actual and perceived fitness. Potential moderating effects of sex and country were considered. Data on motor skill, fitness, as well as self-perception of motor skill and fitness were collected from 145 Australian children and 214 German children (age range 7 to 10 years). For actual motor skill and fitness, mean differences for sex, age and country were found. For perceived motor performance (perceived motor skill and perceived fitness) no mean differences were found for age. Path analyses were performed. The final model showed significant relations between actual performance (object control skill, fitness) and perceived performance (object control skill, fitness). All model paths had low to moderate regression weights with the lowest relationship reported between actual and perceived fitness. Sex and country showed no effects. This integrated approach has led to a better understanding of the relationship between children's perceived and objective performance, and cultural differences within them.


Assuntos
Exercício Físico/psicologia , Destreza Motora/fisiologia , Aptidão Física/psicologia , Autoimagem , Fatores Etários , Austrália , Criança , Teste de Esforço , Feminino , Alemanha , Humanos , Masculino , Modelos Psicológicos , Fatores Sexuais
13.
Int J Sports Med ; 41(10): 688-695, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32485775

RESUMO

The present study expands previous work on eye-hand decoupling deficits in youth with concussion history. It examines whether deficits can be linked to difficulties adapting to new task constraints or meeting ongoing task demands. Data from 59 youth with concussion history (M=11 months post-concussion) and 55 no history controls were analyzed. All 114 participants (M=12.5 yrs.) performed two touchscreen-based eye-hand coordination tasks: A standard task with vision and motor action in alignment, and an eye-hand decoupling task with both spatially decoupled, with twenty trials per task condition. First (trial 1-4), middle (trial 9-12), and last (trial 17-20) trial blocks were analyzed in each condition across groups, as well as first and last blocks only. The latter analysis showed in the first block longer response times in the concussion history group in the eye-hand decoupling condition due to a general slowdown of the reaction times across blocks and a trend for higher movement times. Our findings suggest that youth with concussion history have difficulty to adapt to new task constraints associated with complex skill performance during a short series of trials. These results are relevant for athletic trainers, therapists and coaches who work with youth with concussion history.


Assuntos
Concussão Encefálica/fisiopatologia , Destreza Motora/fisiologia , Esportes Juvenis/lesões , Adolescente , Criança , Humanos , Análise e Desempenho de Tarefas , Esportes Juvenis/fisiologia , Esportes Juvenis/psicologia
14.
J Sports Sci ; 38(17): 1943-1952, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32546052

RESUMO

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player's involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility. This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.


Assuntos
Desempenho Atlético/fisiologia , Aprendizado de Máquina , Esportes com Raquete/fisiologia , Acelerometria , Adolescente , Adulto , Algoritmos , Feminino , Humanos , Masculino , Destreza Motora/fisiologia , Análise de Componente Principal , Esportes com Raquete/classificação , Estudos de Tempo e Movimento , Adulto Jovem
15.
J Sports Sci ; 38(16): 1886-1896, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32583715

RESUMO

Motor competence (MC) in youth is associated with positive health outcomes, yet few achieve their developmental capability. Although numerous MC studies address initial intervention effectiveness, fewer consider intervention sustainability. This study aimed to investigate whether teachers continued to implement an effective MC programme targeting girls (mean age 12.4 ± 0.3 years), three years post-intervention. Ongoing implementation was examined using three domains of the UK Medical Research Council's framework: (i) implementation, (ii) mechanisms of impact, and (iii) context. Teachers (n = 18) completed self-report questionnaires and participated in focus group discussions (FGs). Descriptive statistics analysed questionnaires. FGs were audio recorded, transcribed verbatim and analysed in NVivo 11 using a framework approach. All teachers had continued to implement the programme, or elements thereof, three years post-intervention. The intervention structure, in particular alignment to the physical education context and curriculum, most notably influenced ongoing programme implementation. Improvement, both teacher practice and student performance, emerged as a driver of sustained impact. The programme demand appeared to be the most important facilitator of programme sustainability. Adaptations made to enhance contextual fit of the programme, post-intervention, extended the programme reach. Framed by implementation science, these findings provide valuable insight into programme sustainability and potential scalability.


Assuntos
Destreza Motora/fisiologia , Percepção , Educação Física e Treinamento/métodos , Professores Escolares/psicologia , Adolescente , Saúde do Adolescente , Criança , Currículo , Feminino , Grupos Focais , Humanos , Estudos Longitudinais , Avaliação de Programas e Projetos de Saúde , Autorrelato
16.
J Sports Sci ; 38(18): 2054-2062, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32475221

RESUMO

Cricket fast bowling is a dynamic activity in which a bowler runs up and repeatedly delivers the ball at high speeds. Experimental studies have previously linked ball release speed and several technique parameters with conflicting results. As a result, computer simulation models are increasingly being used to understand the effects of technique on performance. This study evaluates a planar 16-segment whole-body torque-driven simulation model of the front foot contact phase of fast bowling by comparing simulation output with the actual performance of an elite fast bowler. The model was customised to the bowler by determining subject-specific inertia and torque parameters. Good agreement was found between actual and simulated performances with a 4.0% RMS difference. Varying the activation timings of the torque generators resulted in an optimised simulation with a ball release speed 3.5 m/s faster than the evaluation simulation. The optimised technique used more extended front ankle and knee joint angles, increased trunk flexion and a longer delay in the onset of arm circumduction. These simulations suggest the model provides a realistic representation of the front foot contact phase of fast bowling and is suitable to investigate the limitations of kinematic or kinetic variables on fast bowling performance.


Assuntos
Simulação por Computador , Críquete/fisiologia , Pé/fisiologia , Destreza Motora/fisiologia , Adolescente , Articulação do Tornozelo/fisiologia , Braço/fisiologia , Fenômenos Biomecânicos , Humanos , Articulação do Joelho/fisiologia , Masculino , Tronco/fisiologia
17.
J Sports Sci ; 38(18): 2071-2079, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32508219

RESUMO

Studies that have analysed the association between the different movement behaviours and fundamental movement skills (FMS) have considered it in an independent manner, disregarding the compositional nature of 24-h movement behaviours (24-h MB). The aim of this study was to investigate the relationship between the 24-h MB and FMS in preschoolers using a compositional data analysis . Two hundred and four preschoolers (4.5 ± 0.8 years old; 101 boys) provided objectively assessed physical activity (PA) and sedentary behaviour (SB) data (Actigraph wGT3X), and FMS (TGMD-2). Sleep duration (SD) was reported by parents. Association of daily composition of movement behaviours with FMS was explored using compositional analysis and isotemporal substitution (R Core Team, 3.6.1). When considered as a 24-h MB composition (PA, SB and SD), adjusted for age, BMI and sex, the composition predicted locomotor (r2 = 0.31), object control (r2 = 0.19), and total motor score (r2 = 0.35), respectively (all P < 0.001). Reallocation of time from light to moderate-to-vigorous PA was associated with greatest positive changes in total motor score. Achieving adequate balance between movement behaviours over the 24-h period, and its relationship with locomotor and object control skills should be considered and further investigated in early childhood.


Assuntos
Destreza Motora/fisiologia , Movimento/fisiologia , Acelerometria/métodos , Brasil , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Estudos Transversais , Interpretação Estatística de Dados , Exercício Físico/fisiologia , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Pobreza , Comportamento Sedentário , Sono , Fatores de Tempo
18.
J Sports Sci ; 38(18): 2155-2160, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32543286

RESUMO

Imitation jumps are frequently used in training for ski jumping. Yet, the dynamics of these jumps differ considerably. Thus, the relevance of imitation jumps for ski jumping performance is not elucidated. The aim of this study was to investigate the relationship between the technical execution of imitation jumps and ski jumping performance level. We compared the imitation jumps of 11 ski jumpers of different performance levels using a Spearman correlation transform of time traces of the kinetics (measured using force cells and motion capture) of imitation jumps. The kinetic aspects that were related to performance centred on the moment arm of ground reaction force to the centre of mass before the onset of the push-off, angular momentum early in push-off, thigh angle during the main period of push-off and vertical velocity towards the end of push-off. We propose that the thigh angle may be a key element allowing high development of linear momentum while preparing for appropriate aerodynamic position. Furthermore, the findings suggest that the kinetic development prior to (and during) push-off is more important than the kinematic end state at take-off.


Assuntos
Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Condicionamento Físico Humano/métodos , Esqui/fisiologia , Fenômenos Biomecânicos , Comportamento Competitivo/fisiologia , Humanos , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
19.
J Sports Sci ; 38(18): 2127-2148, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32552520

RESUMO

Cross-country skiing is a complex endurance sport requiring technical skills, in addition to considerable physiological and tactical abilities. This review aims to identify biomechanical factors that influence the performance of cross-country skiers. Four electronic databases were searched systematically for original articles in peer-reviewed journals addressing the relationship between biomechanical factors (including kinematics, kinetics, and muscle activation) and performance while skiing on snow or roller skiing. Of the 46 articles included, 22 focused exclusively on the classical technique, 18 on the skating technique, and six on both. The indicators of performance were: results from actual or simulated races (9 articles); speed on specific tracts (6 articles); maximal or peak speed (11 articles); skiing economy or efficiency (11 articles); and grouping on the basis of performance or level of skill (12 articles). The main findings were that i) cycle length, most often considered as a major determinant of skiing speed, is also related to skiing economy and level of performance; ii) higher cycle rate related with maximal speed capacity, while self-selected cycle rate improves skiing economy at sub-maximal speeds; iii) cross-country skiing performance appears to be improved by joint, whole-body, ski, and pole kinematics that promote forward propulsion while minimizing unnecessary movement.


Assuntos
Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Esqui/fisiologia , Aceleração , Braço/fisiologia , Fenômenos Biomecânicos , Humanos , Cinética , Perna (Membro)/fisiologia , Músculo Esquelético/fisiologia , Equipamentos Esportivos
20.
Int J Sports Med ; 41(11): 744-750, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32492732

RESUMO

Sprinting in curvilinear trajectories is an important soccer ability, corresponding to ~85% of the actions performed at maximum velocity in a soccer league. We compared the neuromuscular behavior and foot contact-time between outside leg and inside leg during curve sprinting to both sides in soccer players. Nine soccer players (age=23±4.12 years) performed: 3×Sprint linear, 3×Sprint right curve, and 3×Sprint left curve. An ANOVA with repeated measures was used to compare the differences between inside and outside leg, and Cohen's d was used to calculate the effect-size. Considering the average data, the performance classification (from best to worst) was as follows: 1. Curve "good" side (2.45±0.11 s), 2. Linear (2.47±0.13 s), and 3. Curve "weak" side (2.56±0.17 s). Comparing linear with curve sprinting, inside leg recorded significant differences ("good" and "weak"; effect size=1.20 and 2, respectively); in contrast, for outside leg, there were no significant differences ("good" and "weak"; effect size=0.30 and 0.49, respectively). Electromyography activity showed significant differences (p≤0.05) during curve sprinting between outside (higher in biceps femoris and gluteus medius) and inside leg (higher activity in semitendinosus and adductor). In summary, inside and outside leg play different roles during curved sprints, but inside leg is more affected by the change from straight to curve sprint.


Assuntos
Perna (Membro)/fisiologia , Destreza Motora/fisiologia , Músculo Esquelético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Fenômenos Biomecânicos , Eletromiografia , Teste de Esforço , Pé/fisiologia , Humanos , Estudos de Tempo e Movimento
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