Risk Factors for Non-Contact Lower-Limb Injury: A Retrospective Survey in Pediatric-Age Athletes.

BACKGROUND: Risk factors for non-contact lower-limb injury in pediatric-age athletes and the effects of lateral dominance in sport (laterally vs. non-laterally dominant sports) on injury have not been investigated. PURPOSE: To identify risk factors for non-contact lower-limb injury in pediatric-age athletes. METHODS: Parents and/or legal guardians of 2269 athletes aged between 6-17 years were recruited. Each participant completed an online questionnaire that contained 10 questions about the athlete's training and non-contact lower-limb injury in the preceding 12 months. RESULTS: The multivariate logistic regression model determined that lateral dominance in sport (adjusted OR (laterally vs. non-laterally dominant sports), 1.38; 95% CI, 1.10-1.75; p = 0.006), leg preference (adjusted OR (right vs. left-leg preference), 0.71; 95% CI, 0.53-0.95; p = 0.023), increased age (adjusted OR, 1.21; 95% CI, 1.16-1.26; p = 0.000), training intensity (adjusted OR, 1.77; 95% CI, 1.43-2.19; p = 0.000), and training frequency (adjusted OR, 1.36; 95% CI, 1.25-1.48; p = 0.000) were significantly associated with non-contact lower-limb injury in pediatric-age athletes. Length of training (p = 0.396) and sex (p = 0.310) were not associated with a non-contact lower-limb injury. CONCLUSIONS: Specializing in laterally dominant sports, left-leg preference, increase in age, training intensity, and training frequency indicated an increased risk of non-contact lower-limb injury in pediatric-age athletes. Future research should take into account exposure time and previous injury.

The Pen Is Not Always Mightier: Different Ways of Measuring Handedness With the Edinburgh Handedness Inventory Yield Different Handedness Conclusions.

Although consistency of handedness (the strength of dominant hand preference) is increasingly recognized as an important individual difference, there are questions about how to best measure it. A recent meta-analysis showed that researchers have often failed to report details of responses and response formats to handedness test items. In addition to measuring handedness direction (i.e., left versus right handedness), there can be utility to dichotomizing the Edinburgh Handedness Inventory (EHI) into consistent and inconsistent dominant handedness, despite controversy over the best means of doing so. In this study, we performed a discriminant function analysis of EHI items to determine which items best predicted handedness consistency versus handedness direction. Although the same discriminant function accounted for most of the variance for both dependent measures, writing and drawing EHI items were the strongest predictors of handedness direction and combing and opening jars items were the strongest predictors of handedness consistency. As different items on the EHI predicted these different handedness dimensions, we discuss the implications of dichotomizing EHI items into both relevant dimensions for both biological and environmental theories of the basis of handedness and for future handedness research.

COLLEGIATE MALE SOCCER PLAYERS EXHIBIT BETWEEN-LIMB SYMMETRY IN BODY COMPOSITION, MUSCLE STRENGTH, AND RANGE OF MOTION.

BACKGROUND: Functional and structural asymmetries attributed to limb dominance are equivocal in soccer players. Previous authors hypothesize the existence of between-limb asymmetry secondary to the repetitive unilateral nature of kicking. However, symmetry is often present, particularly in measures of muscle strength. PURPOSE: The purpose of the present study was to determine if lateral dominance is accompanied by corresponding between-limb asymmetries in a comprehensive assessment of body composition, muscle strength, and range of motion in healthy soccer players. STUDY DESIGN: Cross-sectional, observational. METHODS: 17 healthy male NCAA Division One collegiate soccer players participated (age 19.6 ± 1.5 years; BMI 23.9 ± 1.4 kg/m2). Footedness was attained via participant self-report. Lower limb muscle strength (hand held dynamometry), range of motion (goniometry), and body composition (dual energy x-ray absorptiometry scan) were measured. Lower-leg symmetry was analyzed comparing the dominant versus non-dominant limb using paired t-tests. RESULTS: Comparisons revealed no statistically different differences in outcomes, indicating remarkable symmetry in all measures of body composition, muscle strength, and range of motion (p>0.05) between the dominant and non-dominant lower limbs. CONCLUSIONS: The authors speculate the prevalence of running versus kicking, the longitudinal effects of playing careers, and/or functional compensation attenuates the expected asymmetries in healthy male collegiate soccer players. LEVEL OF EVIDENCE: 2b.

Relationships between Bat Swing Speed and Muscle Thickness and Asymmetry in Collegiate Baseball Players.

The purpose of the present study was to examine the relationships between bat swing speed (BSS), muscle thickness, and muscle thickness asymmetry in collegiate baseball players. Twenty-four collegiate baseball players participated in this study. Maximum BSS in hitting a teed ball was measured using a motion capture system. The muscle thicknesses of the trunk (upper abdominal rectus, central abdominal rectus, lower abdominal rectus, abdominal wall, and multifidus lumborum), upper limb, and lower limb were measured using a B-mode ultrasonography. Lateral asymmetry between each pair of muscles was determined as the ratio of the thickness of the dominant side to that of the non-dominant side. Statistically significant positive correlations were observed between BSS and muscle thicknesses of the abdominal wall and multifidus lumborum on the dominant side (r = 0.426 and 0.431, respectively; p < 0.05), whereas only trends against this significance were observed between BSS and muscle thicknesses on the non-dominant side. No statistical correlations were found between BSS and the lateral asymmetry of any muscles. These findings indicate the importance of the trunk muscles for bat swing, and the lack of association between BSS and lateral asymmetry of muscle size.

The effect of stopping before turning on the direct observational measure of whole body turning bias.

Turning bias, the preferential tendency to turn toward a given direction has been reported in both rodents and human participants. The observational gait method of determining turning bias in humans requires a stop prior to turning. This study removed the stop and hypothesised that turning bias would remain the same between stop and non-stop conditions if bias was solely under the control of neurochemical asymmetries. The results showed that statistically turning bias remained the same (to the left) regardless of method used but there was no agreement between the methods thus rejecting the hypothesis. It is likely that when not stopping biomechanical factors related to gait when turning influence the direction of turn rather than solely neurochemical asymmetries.

Framing effects: the influence of handedness and access to right hemisphere processing.

Changing how information is framed, such that the same critical information is cast in a positive or negative light, has a powerful impact on judgements and decision making. Research indicates that the influence of frames may be driven by participants' initial affective response and that the right hemisphere is sensitive to the emotional connotation of stimuli. While previous research tested the effects of hemispheric differences on framing effects by inducing asymmetrical activation, the current study explored how stable brain differences may account for differences in susceptibility to framing effects. Because mixed degree of handedness is associated with increased access to right hemisphere processes, mixed-handed participants were expected to be more susceptible to the effects of framing than strong-handed participants. Participants responded to the Asian disease problem and completed as assessment of handedness. Although mixed- and strong-handed participants were affected differently, the results were not consistent with the hypothesis. Mixed-handed participants conformed to risky choice framing effects when options were framed negatively and showed no effect of the positive frame. Strong-handed participants conformed to positively framed options and showed no effect of the negative frame. Possible explanations are discussed.

Especialização hemisférica cerebral e assimetrias comportamentais: o lado da cama tem gênero? / Cerebral hemispheric specialization and behavioral asymmetries: does the side of bed have a gender?

Dados acerca do lado da cama onde as mulheres dormem foram coletados para subsidiar a validade de um projeto amplo para determinar se esta atividade é lateralizada. Informações a respeito do lado que ocupam na cama de casal, sua lateralidade manual, o tempo de convívio do casal e outros itens adicionais foram coletados em amostra de 229 mulheres com idades de 20 a 65 anos. As frequências totais de ocupação nos lados da cama se mostraram estatisticamente equivalentes, porém o lado esquerdo mostrou ser significantemente (Χ² = 5,44, 1 g.l., p<0,05) mais escolhido (70 por cento) nos casos em que a escolha foi feita espontaneamente (i.e, não determinada por fatores impositivos). Conclui-se que os dados indicam a validade da pesquisa proposta que se insere na linha de estudos dedicados à compreensão dos mecanismos de funcionamento do sistema nervoso central.

Data relative on the side occupied by females in double beds were collected in order to evaluate the feasebility to carry-out a more extensive study to determine if this behavioral pattern is lateralized. Information relative to the side occupied in the bed, manual lateralization, how long lived togheter, and other related questions were collected in a sample of 229 women aged from 20 to 65 years old. Total frequencies of the bed side occupied showed to be equivalent, however, the left side showed to be chosen significantly more (70 percent)(Χ² = 5.4; 1 d.f.; p<0.05) when the choice was stated to be spontaneous (i.e, not determined by an impositive factor). It is concluded that the obtained data give favourable support to an extensive study on the subject, which inserts into the area of research devoted to the understanding of the functional characteristics of central nervous functioning.

Especialização hemisférica cerebral e assimetrias comportamentais: o lado da cama tem gênero? / Cerebral hemispheric specialization and behavioral asymmetries: does the side of bed have a gender?

Dados acerca do lado da cama onde as mulheres dormem foram coletados para subsidiar a validade de um projeto amplo para determinar se esta atividade é lateralizada. Informações a respeito do lado que ocupam na cama de casal, sua lateralidade manual, o tempo de convívio do casal e outros itens adicionais foram coletados em amostra de 229 mulheres com idades de 20 a 65 anos. As frequências totais de ocupação nos lados da cama se mostraram estatisticamente equivalentes, porém o lado esquerdo mostrou ser significantemente (Χ² = 5,44, 1 g.l., p<0,05) mais escolhido (70 por cento) nos casos em que a escolha foi feita espontaneamente (i.e, não determinada por fatores impositivos). Conclui-se que os dados indicam a validade da pesquisa proposta que se insere na linha de estudos dedicados à compreensão dos mecanismos de funcionamento do sistema nervoso central.(AU)

Data relative on the side occupied by females in double beds were collected in order to evaluate the feasebility to carry-out a more extensive study to determine if this behavioral pattern is lateralized. Information relative to the side occupied in the bed, manual lateralization, how long lived togheter, and other related questions were collected in a sample of 229 women aged from 20 to 65 years old. Total frequencies of the bed side occupied showed to be equivalent, however, the left side showed to be chosen significantly more (70 percent)(Χ² = 5.4; 1 d.f.; p<0.05) when the choice was stated to be spontaneous (i.e, not determined by an impositive factor). It is concluded that the obtained data give favourable support to an extensive study on the subject, which inserts into the area of research devoted to the understanding of the functional characteristics of central nervous functioning.(AU)

Sobre a relação entre filogenia e ontogenia no desenvolvimento da lateralidade na infância / The relationship between phylogeny and ontogeny in the development of infant laterality

A lateralidade humana tem sido concebida como sendo predominantemente o resultado de fatores filogenéticos do desenvolvimento humano, enquanto que apenas importância secundária tem sido atribuída à interação indivíduo-ambiente. Neste estudo é apresentada uma revisão crítica da literatura com indicadores da influência de fatores filo e ontogenéticos no desenvolvimento da lateralidade, com particular ênfase aos primeiros anos de vida. A partir dos resultados discutidos, propomos que a lateralidade humana é um processo dinâmico, com efeitos marcantes das experiências sensório-motoras lateralizadas sobre a preferência manual e assimetrias interlaterais de desempenho motor.

Human laterality has been conceived as resulting, predominantly, from phylogenetic factors in human development, whereas individual-environment interaction is thought to play only a minor role. This study aims at presenting a critical review of literature showing evidence of the effect of phylogenetic and ontogenetic factors on the development of laterality, with particular emphasis on the first years of life. From the results presented, we propose that human laterality is a dynamic process, with sharp effects of lateralized sensorimotor experiences over manual preference and interlateral asymmetry of motor performance.

Sobre a relação entre filogenia e ontogenia no desenvolvimento da lateralidade na infância / The relationship between phylogeny and ontogeny in the development of infant laterality

A lateralidade humana tem sido concebida como sendo predominantemente o resultado de fatores filogenéticos do desenvolvimento humano, enquanto que apenas importância secundária tem sido atribuída à interação indivíduo-ambiente. Neste estudo é apresentada uma revisão crítica da literatura com indicadores da influência de fatores filo e ontogenéticos no desenvolvimento da lateralidade, com particular ênfase aos primeiros anos de vida. A partir dos resultados discutidos, propomos que a lateralidade humana é um processo dinâmico, com efeitos marcantes das experiências sensório-motoras lateralizadas sobre a preferência manual e assimetrias interlaterais de desempenho motor.(AU)

Human laterality has been conceived as resulting, predominantly, from phylogenetic factors in human development, whereas individual-environment interaction is thought to play only a minor role. This study aims at presenting a critical review of literature showing evidence of the effect of phylogenetic and ontogenetic factors on the development of laterality, with particular emphasis on the first years of life. From the results presented, we propose that human laterality is a dynamic process, with sharp effects of lateralized sensorimotor experiences over manual preference and interlateral asymmetry of motor performance.(AU)

Lateralidade manual, ocular e dos membros inferiores e sua relação com déficit de organização espacial em escolares / Hand-eye-foot laterality and its relation to spatial organization deficit in schoolchildren

Este estudo teve por objetivos: 1) verificar se existe associação entre lateralidade manual, ocular e dos membros inferiores e déficit de organização espacial em escolares; 2) categorizar as variações de lateralidade nesta população. A amostra foi constituída de 400 crianças na faixa etária de 6 a 10 anos de escolas públicas e privadas da cidade de João Pessoa (PB). A lateralidade e a organização espacial foram avaliadas, respectivamente, por meio do Harris Test of Lateral Dominance e da Bateria de Piaget-Head. Os resultados evidenciaram 23 tipos de lateralidade mão-olho-pé, observando-se maior percentual (48,75 por cento) de destralidade completa (dominância manual, ocular e dos membros inferiores direita). Houve associação significativa (p<0,05) entre sinistralidade completa e déficit de organização espacial. Os resultados atentam para a importância de se inserirem no cotidiano escolar programas de estimulação motora voltados à lateralidade e à organização espacial das crianças, como forma de prevenir distorções no seu processo de aprendizagem.

The purposes of this study were 1) to verify the relationship between hand-eye-foot laterality and spatial organization deficit in schoolchildren, and 2) to categorize the variations in laterality in this population. The sample comprised 400 children aged 6-10 from public and private schools in João Pessoa (Paraíba state, Brazil). Laterality and spatial organization were assessed using the Harris Test of Lateral Dominance and the Piaget-Head Battery, respectively. The results demonstrated 23 types of hand-eye-foot laterality, with the highest proportion (48.75 percent) showing pure dextrality (right-handedness, right-eyedness and right-footedness). Pure sinistrality was significantly (p<0.05) associated with spatial organization deficit. The results point to the importance of implementing motor stimulation programs which focus on children's laterality and spatial organization during the daily school routine, as a means to preventing and intervening in distortions in their learning process.

Lateralidade manual, ocular e dos membros inferiores e sua relação com déficit de organização espacial em escolares

Este estudo teve por objetivos: 1) verificar se existe associação entre lateralidade manual, ocular e dos membros inferiores e déficit de organização espacial em escolares; 2) categorizar as variações de lateralidade nesta população. A amostra foi constituída de 400 crianças na faixa etária de 6 a 10 anos de escolas públicas e privadas da cidade de João Pessoa (PB). A lateralidade e a organização espacial foram avaliadas, respectivamente, por meio do Harris Test of Lateral Dominance e da Bateria de Piaget-Head. Os resultados evidenciaram 23 tipos de lateralidade mão-olho-pé, observando-se maior percentual (48,75 por cento) de destralidade completa (dominância manual, ocular e dos membros inferiores direita). Houve associação significativa (p<0,05) entre sinistralidade completa e déficit de organização espacial. Os resultados atentam para a importância de se inserirem no cotidiano escolar programas de estimulação motora voltados à lateralidade e à organização espacial das crianças, como forma de prevenir distorções no seu processo de aprendizagem.(AU)

The purposes of this study were 1) to verify the relationship between hand-eye-foot laterality and spatial organization deficit in schoolchildren, and 2) to categorize the variations in laterality in this population. The sample comprised 400 children aged 6-10 from public and private schools in João Pessoa (Paraíba state, Brazil). Laterality and spatial organization were assessed using the Harris Test of Lateral Dominance and the Piaget-Head Battery, respectively. The results demonstrated 23 types of hand-eye-foot laterality, with the highest proportion (48.75 percent) showing pure dextrality (right-handedness, right-eyedness and right-footedness). Pure sinistrality was significantly (p<0.05) associated with spatial organization deficit. The results point to the importance of implementing motor stimulation programs which focus on children's laterality and spatial organization during the daily school routine, as a means to preventing and intervening in distortions in their learning process.(AU)

Memória de longo prazo modulada pela memória de curto prazo / Memoria a largo plazo modulada por la memoria a corto plazo / Long term memory modulated by short term memory

Quando um estímulo ocorre aleatoriamente à esquerda ou à direita, a resposta é mais rápida quando estímulo e resposta estão no mesmo lado (condição compatível) do que em lados opostos (condição incompatível). Na tarefa de Simon, embora a resposta seja selecionada pela forma (ou cor) do estímulo, a posição deste influencia o Tempo de Reação Manual (TRM). O efeito Simon corresponde à diferença entre as médias dos TRMs nas duas condições (incompatível e compatível). Neste trabalho, estudamos como uma tarefa prévia de compatibilidade realizada com um dedo indicador modula o efeito Simon. Vinte e oito voluntários realizaram uma tarefa de compatibilidade seguida pela tarefa de Simon. No grupo compatível (14 voluntários), encontramos um efeito Simon de 24 ms. No incompatível (14 voluntários), ocorreu um efeito Simon inverso de -16 ms. Estes resultados mostram uma modulação da memória de longo prazo por uma tarefa envolvendo a memória de curto prazo.

When a stimulus randomly occurs at left or right, the response is faster when stimulus and response are on the same side (compatible condition) than on opposite sides (incompatible condition). In the Simon task, color or shape determines the correct response but it is faster when there is correspondence between stimulus and response key positions. In this research, we studied the Simon effect modulation through a previous spatial compatibility task in which just one index finger presses the keys. Twenty-eight volunteers run compatibility tasks (14 compatible and 14 incompatible). Then, they performed a Simon task in which the correct response was selected by shape. A Simon effect of 24 ms was found in the compatible group. An inverse Simon effect of -16 ms occurred in the incompatible group. These results show long-term memory modulation by task involving short-term memory.

Cuando un estimulo ocurre aleatoriamente a la izquierda o a la derecha, la respuesta es más rápida cuando el estimulo y la respuesta están del mismo lado (condición compatible), de que cuando están en lados opuestos (condición incompatible). En la prueba de Simon, el color o la forma del estímulo determina la respuesta, pero éste es más rápido cuando hay una correlación espacial entre el estímulo y la respuesta. En este trabajo, estudiamos la modulación del efecto Simon por la tarea de la compatibilidad espacial en la cual uno dedo índice respondió. Veintiocho voluntarios realizaron la prueba de compatibilidad (14 la compatible y 14 la incompatible). Después el voluntario realizó la prueba de Simon. En el grupo compatible, encontramos efecto de Simon de 21 ms. Sin embargo, en el grupo incompatibles, ocurrió un efecto de Simon inverso de -16 ms. Estos resultados demuestran una modulación de la memoria a largo plazo por la memoria a corto plazo.