Changes in Foot Biomechanics during Pregnancy and Postpartum: Scoping Review.

(1) Background: During pregnancy, changes in foot biomechanics affect structural stability and gait. (2) Objective: To map the available evidence for changes in foot biomechanics during pregnancy and the postpartum period. (3) Methods: Scoping review according to the methodology of the Joanna Briggs Institute through the relevant databases via EBSCO, MEDLINE with full text, BioOne Complete, CINAHL Plus with full text, Academic Search Complete, and SPORT Discus with full text. The search was conducted in SCOPUS and PubMed. (4) Results: Eight studies were included in the scoping review. Two independent reviewers performed data extraction and synthesized data in narrative form. We found that changes in the length and volume of the foot occur during pregnancy and remain in the postpartum period. (5) Conclusions: During pregnancy, anatomical and biomechanical changes occur in the pregnant woman's foot, potentially contributing to the risk of musculoskeletal disorders. However, more research is needed to determine whether these biomechanical changes can lead to the risk of musculoskeletal disorders.

Predictability and Complexity of Fine and Gross Motor Skills in Fibromyalgia Patients: A Pilot Study.

BACKGROUND: Fine and gross motor tasks are usually used to evaluate behavioral dysfunctions and can be applied to diseases of the central nervous system, such as fibromyalgia (FM). Non-linear measures have allowed for deeper motor control analysis, focusing on the process and on the quality of movement. Therefore, to assess uncertainty, irregularity, and structural richness of a time series, different algorithms of entropy can be computed. The aim of this study was to (i) verify the single-scale and multiscale entropy values in fine and gross motor movements and (ii) to verify whether fine and gross motor tasks are sensitive to characterizing FM patients. METHODS: The sample consisted of 20 females (46.2 ± 12.8 years) divided in two groups, an experimental group with 10 FM subjects and a control group with 10 subjects without FM. Inertial sensors were used to collect the finger tapping test (FTT), walking, and sit-and-stand task data. RESULTS: Regarding fine motor skills, patients with FM showed a loss of structural richness (complexity), but they had information processing with greater control in the FTT, probably to simplify task execution and for correction of the movement. On the other hand, people without FM seemed to have more automatic control of the movement when performed with the preferred hand and exhibited similar difficulties to the FM group when performed with the non-preferred hand. Gross motor tasks showed similar entropy values for both groups. CONCLUSIONS: The results show that FM patients have movement controls primarily at the level of the motor cortex, whereas people without FM perform movement at the medullary level, especially in fine motor tasks, indicating that the FTT is sensitive to the presence of FM, especially when performed with the preferred hand.

Accuracy and Interpretation of the Acceleration from an Inertial Measurement Unit When Applied to the Sprint Performance of Track and Field Athletes.

In this study, we aimed to assess sprinting using a developed instrument encompassing an inertial measurement unit (IMU) in order to analyze athlete performance during the sprint, as well as to determine the number of steps, ground contact time, flight time, and step time using a high-speed camera as a reference. Furthermore, we correlated the acceleration components (XYZ) and acceleration ratio with the performance achieved in each split time obtained using photocells. Six athletes (four males and two females) ran 40 m with the IMU placed on their fifth lumbar vertebra. The accuracy was measured through the mean error (standard deviation), correlation (r), and comparison tests. The device could identify 88% to 98% of the number of steps. The GCT, flight time, and step time had mean error rates of 0.000 (0.012) s, 0.010 (0.011) s, and 0.009 (0.009) s when compared with the high-speed camera, respectively. The step time showed a correlation rate of r = 0.793 (p = 0.001) with no statistical differences, being the only parameter with high accuracy. Additionally, we showed probable symmetries, and through linear regression models identified that higher velocities result in the maximum anteroposterior acceleration, mainly over 0-40 m. Our device based on a Wi-Fi connection can determine the step time with accuracy and can show asymmetries, making it essential for coaches and medical teams. A new feature of this study was that the IMUs allowed us to understand that anteroposterior acceleration is associated with the best performance during the 40 m sprint test.

Learning to Cycle: Is Velocity a Control Parameter for Children's Cycle Patterns on the Balance Bike?

The balance bike (BB) has been pointed out as being the most efficient learning bicycle due to its inherent stimulation of balance. However, the process of acquiring the control of balance on the BB has not been explored. This study aimed to: (i) categorize the cycle patterns of children on the BB, (ii) compare the cycle patterns in different stages of learning (before and after six sessions of a BB practice program), and (iii) verify whether velocity is a control parameter leading to transitions between different cycle patterns on a BB. The data were collected during the Learning to Cycle program from 12 children aged 6.06 ± 1.25 years. The velocity was measured using an inertial sensor. Seven different movement patterns were captured and categorized through video analysis. After practice, there was an increase in the mean number of different patterns and in the global mean and maximum velocity. These were interpreted as an improvement of the motor competence in the use of the BB. The results obtained support the hypothesis that velocity is a control parameter which leads to the emergence of diverse patterns of behavior. As the speed increased, the amount of foot contact with the ground became less frequent and the locomotor modes that imply that longer flight phases began to emerge.

Accuracy of Inertial Measurement Units When Applied to the Countermovement Jump of Track and Field Athletes.

In this study, we aimed to assess the countermovement jump (CMJ) using a developed instrument encompassing an off-the-shelf Inertial Measurement Unit (IMU) in order to analyze performance during the contraction phase, as well as to determine the jump height and the modified reactive strength index (RSImod), using force plate (FP) data as reference. Eight athletes (six males and two females) performed CMJs with the IMU placed on their fifth lumbar vertebra. Accuracy was measured through mean error (standard deviation), correlation, and comparison tests. The results indicated high accuracy, high correlation (r), and no statistical differences between the IMU and the FP for contraction time (r = 0.902; ρ < 0.001), negative impulse phase time (r = 0.773; ρ < 0.001), flight time (r = 0.737; ρ < 0.001), jump time (r = 0.708; ρ < 0.001), RSImod (r = 0.725; ρ < 0.001), nor minimum force (r = 0.758; ρ < 0.001). However, the values related to the positive impulse phase did not have the expected accuracy, as we used different devices and positions. Our results demonstrated that our developed instrument could be utilized to identify the contraction phase, jump height, RSImod, and minimum force in the negative impulse phase with high accuracy, obtaining a signal similar to that of an FP. This information can help coaches and athletes with training monitoring and control, as the device has simpler applicability making it more systematic.

Learning to Cycle: A Cross-Cultural and Cross-Generational Comparison.

Background: Learning to cycle is an important milestone for children, but the popularity of cycling and the environmental factors that promote the development and practice of this foundational movement skill vary among cultures and across time. This present study aimed to investigate if country of residence and the generation in which a person was born influence the age at which people learn to cycle. Methods: Data were collected through an online survey between November 2019 and December 2020. For this study, a total of 9,589 responses were obtained for adults (self-report) and children (parental report) living in 10 countries (Portugal, Italy, Brazil, Finland, Spain, Belgium, United Kingdom, Mexico, Croatia, and the Netherlands). Participants were grouped according to their year of birth with 20-year periods approximately corresponding to 3 generations: 1960-79 (generation X; n = 2,214); 1980-99 (generation Y; n = 3,994); 2000-2019 (generation Z; n = 3,381). Results: A two-way ANOVA showed a significant effect of country, F(9,8628) = 90.17, p < 0.001, ηp2 = 0.086, and generation, F(2,8628) = 47.21, p < 0.001, ηp2 = 0.122, on the age at which individuals learn to cycle. Countries with the lowest learning age were the Netherlands, Finland and Belgium and countries with the highest learning age were Brazil and Mexico. Furthermore, the age at which one learns to cycle has decreased across generations. There was also a significant country x generation interaction effect on learning age, F(18,8628) = 2.90, p < 0.001; however, this effect was negligible ( ηp2 = 0.006). Conclusions: These findings support the socio-ecological perspective that learning to cycle is a process affected by both proximal and distal influences, including individual, environment and time.

Learning to Cycle: From Training Wheels to Balance Bike.

BACKGROUND: Learning to cycle is an important milestone in a child's life, so it is important to allow them to explore cycling as soon as possible. The use of a bicycle with training wheels (BTW) for learning to cycling is an old approach practiced worldwide. Most recently, a new approach using the balance bike (BB) has received increased attention, and several entities believe that this could be most efficient. Drawing on the work of Bronfenbrenner (1995) and Newel (1986), this study aimed to analyse the effect of BB's use on the learning process of cycling independently. METHODS: Data were collected in Portugal from an online structured survey between November 2019 and June 2020. RESULTS: A total of 2005 responses were obtained for adults and children (parental response). Results revealed that when the BB's approach was used, learning age (LA) occurred earlier (M = 4.16 ± 1.34 years) than with the BTW's approach (M = 5.97 ± 2.16 years) (p < 0.001); or than when there was only the single use of the traditional bicycle (M =7.27 ± 3.74 years) (p < 0.001). CONCLUSIONS: Children who used the BB as the first bike had a significantly lower LA than children who did not use it (p < 0.001). To maximize its effects, the BB should be used in the beginning of the learning process.

High-content image analysis to study phenotypic heterogeneity in endothelial cell monolayers.

Endothelial cells (ECs) are heterogeneous across and within tissues, reflecting distinct, specialised functions. EC heterogeneity has been proposed to underpin EC plasticity independently from vessel microenvironments. However, heterogeneity driven by contact-dependent or short-range cell-cell crosstalk cannot be evaluated with single cell transcriptomic approaches, as spatial and contextual information is lost. Nonetheless, quantification of EC heterogeneity and understanding of its molecular drivers is key to developing novel therapeutics for cancer, cardiovascular diseases and for revascularisation in regenerative medicine. Here, we developed an EC profiling tool (ECPT) to examine individual cells within intact monolayers. We used ECPT to characterise different phenotypes in arterial, venous and microvascular EC populations. In line with other studies, we measured heterogeneity in terms of cell cycle, proliferation, and junction organisation. ECPT uncovered a previously under-appreciated single-cell heterogeneity in NOTCH activation. We correlated cell proliferation with different NOTCH activation states at the single-cell and population levels. The positional and relational information extracted with our novel approach is key to elucidating the molecular mechanisms underpinning EC heterogeneity.

The influence of physical activity on the prevalence of low back pain among the portuguese population / Influência da atividade física sobre a prevalência da dor lombar na população portuguesa / La influencia de la actividad física en la prevalencia del dolor de la región lumbar en la población portuguesa

ABSTRACT Objective: I) To investigate the influence of physical activity (PA) on levels of low back pain, and II) To classify the respondents regarding low back pain. Methods: Collection of responses, through an online questionnaire, from 199 adults aged between 18 and 65 years (36.05 ± 11.90 years). The following inclusion criteria were applied: I) Suffering or have suffered pain in the spine at some point in life; and as an exclusion criterion: I) Being outside the required age range. Results: Investigating the level of pain and the risk of low back pain, there was a significant association (r = 0.481; p≤0.01) between these two factors, indicating that the higher the levels of pain, the higher the risk of low back pain. Those who presented higher levels of chronic pain either did not practice any physical activity (58.8%), or practiced formal PA (42.9%) or practiced informal PA (30.7%). Those who had practiced physical exercise for three months or more mostly did not have chronic pain (70.1%). Conclusions: There was a decrease in chronic low back pain which was associated with increased time and frequency of PA, as well as the practice of postural physical exercises. Level of Evidence I; Prognostic Studies— Investigating the Effect of a Patient Characteristic on the Outcome of Disease.

RESUMO: Objetivo: I) Verificar a influência da atividade física (AF) nos níveis de lombalgia, II) Classificar os entrevistados quanto à dor lombar. Métodos: As respostas foram obtidas por meio de um questionário on-line respondido por 199 adultos com idades entre 18 e 65 anos (36,05 ± 11,90 anos). Foram aplicados os seguintes critérios de inclusão: I) Sofrer ou ter sofrido dor na coluna em algum momento da vida e de exclusão: I) Não pertencer à faixa etária determinada. Resultados: Ao analisar o nível de dor e o risco de lombalgia verificou-se uma associação significativa (r = 0,481; p ≤ 0,01) entre esses dois fatores, o que indica que quanto maiores os índices de dor, mais alto é o risco de lombalgia. Os participantes que apresentaram valores maiores de dor crônica não praticavam atividade física (58,8%), praticavam AF formal (42,9%) ou praticavam AF informal (30,7%). A maioria dos participantes que praticavam exercício físico há 3 meses ou mais não tinha dor crônica (70,1%). Conclusões: Houve diminuição da dor lombar crônica que foi associada ao aumento do tempo e frequência de AF, bem como à prática de exercícios físicos posturais. Nível de Evidência I; Estudos prognósticos - investigação do efeito de característica de um paciente sobre o desfecho da doença.

RESUMEN: Objetivos: I) Verificar la influencia de la actividad física (AF) en los niveles de dolor de la región lumbar, II) Clasificar a los encuestados en relación con el dolor de la región lumbar. Métodos: Las respuestas se obtuvieron a través de un cuestionario online al que respondieron 199 adultos de entre 18 y 65 años (36,05 ± 11,90 años). Se aplicaron los siguientes criterios de inclusión: I) Padecer o haber padecido dolor de columna en algún momento de la vida; y como criterio de exclusión: I) No pertenecer al grupo de edad indicado. Resultados: Al analizar el nivel de dolor y el riesgo de lumbalgia se observó una asociación significativa (r = 0,481; p ≤0,01) entre estos dos factores, lo que indica que cuanto mayor es el índice de dolor, mayor es el riesgo de lumbalgia. Los participantes que presentaron valores más altos de dolor crónico o no practicaban actividad física (58,8%), practicaban AF formal (42,9%) o practicaban AF informal (30,7%). La mayoría de los participantes que practicaban ejercicio físico durante 3 o más meses no presentaba dolor crónico (70,1%). Conclusiones: Hubo una disminución del dolor de la región lumbar crónico que se asoció con el aumento del tiempo y la frecuencia de AF, así como con la práctica de ejercicios físicos posturales. Nivel de Evidencia I; Estudios de pronóstico - investigación del efecto de una característica del paciente sobre el resultado de la enfermedad.

The effect of pilates exercises on muscle electrical activation in adults with chronic low back pain: a systematic review / Efeito dos exercícios de pilates na ativação elétrica muscular em adultos com lombalgia crónica: revisão sistemática / El efecto de los ejercicios de pilates sobre la activación eléctrica muscular en adultos con lumbalgia crónica: revisión sistemática

ABSTRACT Low back pain is one of the most prevalent orthopedic conditions, affecting around 70% to 80% of the world's population at least once during their life times. Surface electromyography is an important tool for assessing the muscle function of the lumbar stabilizers. One of the best treatment options for patients with chronic low back pain (CLBP) is physical exercise, particular lyaerobic exercise and Pilates, as these can reduce short-term pain and disability, and improve balance. This review aims to identify the state of art regarding the benefits of pilates on the population with CLBP, evaluating changes in the muscular activation of the muscles of the lumbar region. Searches were conducted on the following databases: PubMed (Medline), Science Direct, Scopus, Web of Science, Cochrane, Ebsco and Scielo; including gray literature: Google Scholar, Grey Literature, Pro Quest Dissertations & Theses. The inclusion criteria were adults with low back pain for three months or more, with or without referred pain in the lower limbs; studies that used electromyographic variables; studies with a pain assessment measure at two different times; studies with physical exercise performed only using the Pilates method. Applying these criteria, the searches retrieved 439 abstracts. Of these, 44 articles were evaluated for eligibility, and three fulfilled the qualitative and quantitative synthesis criteria. The average methodological quality score on the Downs and Black checklist was 15 out of 28. It was therefore concluded that Pilates is an excellent option for the treatment of non-specific low back pain, promoting health and helping prevent low back pain among asymptomatic individuals. Level of evidence II; Systematic Review of Level II or Level I Studies with Discrepant Results.

RESUMO: A dor lombar é uma das condições ortopédicas mais prevalentes, afetando cerca de 70% a 80% da população mundial pelo menos uma vez na vida. A eletromiografia de superfície é um importante instrumento de avaliação da função muscular dos estabilizadores lombares. Uma das melhores opções de tratamento de pacientes com dor lombar crônica (DLC) é o exercício físico, principalmente exercícios aeróbicos e Pilates, considerando que podem reduzir a dor e a incapacidade a curto prazo e melhorar o equilíbrio. Esta revisão objetivou identificar o estado da arte quanto aos benefícios do pilates para a população com DLC, por meio da avaliação das alterações da ativação muscular dos músculos da região lombar. A pesquisa foi realizada nas seguintes bases de dados: PubMed (Medline), Science Direct, Scopus, Web of Science, Cochrane, Ebsco e Scielo, incluindo também literatura cinzenta: Google Acadêmico, Grey Literature, Pro Quest Dissertations & Theses. Os critérios de inclusão foram adultos com lombalgia há três meses ou mais meses, com ou sem dor referida nos membros inferiores; estudos que que usaram variáveis eletromiográficas; estudos com medida de avaliação da dor em dois momentos distintos; estudos com exercícios físicos realizados apenas com o método Pilates. Com esses critérios, foram identificados 439 resumos. Desse total, 44 artigos foram avaliados quanto à elegibilidade e três satisfizeram os critérios de síntese qualitativa e quantitativa. A pontuação média de qualidade metodológica foi 15 de 28 na lista de verificação Downs e Black. Concluiu-se, portanto, que o Pilates é uma excelente opção no tratamento de dores lombares não específicas, resultando na promoção de saúde e na prevenção desta condição para indivíduos assintomáticos. Nível de evidência II; Revisão sistemática de Estudos de Nível II ou Nível I com resultados discrepantes.

RESUMEN: La lumbalgia es una de las afecciones ortopédicas más prevalentes, que afecta a entre el 70% y 80 % de la población mundial al menos una vez en la vida. Las electromiografía de superficie es una herramienta importante para evaluar la función muscular de los estabilizadores lumbares. Una de las mejores opciones de tratamiento para pacientes con dolor lumbar crónico (DLC) es el ejercicio físico, concretamente los ejercicios aeróbicos y el pilates, ya que pueden reducir el dolor y la discapacidad a corto plazo y mejorar el equilibrio. Esta revisión tuvo como objetivo identificar el estado del arte en cuanto a los beneficios del pilates para la población con DLC, evaluando los cambios en la activación muscular de los músculos de la región lumbar. La investigación se realizó en las siguientes bases de datos: PubMed (Medline), Science Direct, Scopus, Web of Science, Cochrane, Ebsco y Scielo; incluyendo también la literatura gris: Google Scholar, Grey Literature, Pro Quest Dissertations & Theses. Los criterios de inclusión fueron adultos con lumbalgia durante 3 meses o más, con o sin dolor referido en miembros inferiores; estudios que han utilizado variables electromiográficas; estudios con medición de la evaluación del dolor en dos momentos diferentes; estudios con ejercicios físicos realizados sólo con el método Pilates. Con estos criterios, se identificaron 439 resúmenes. De este total, se evaluó la elegibilidad de 44 artículos y 3 cumplieron los criterios de síntesis cualitativa y cuantitativa. La puntuación media de calidad metodológica fue de 15 sobre 28 en la lista de verificación de Downs y Black. Por lo tanto, se concluyó que el Método Pilates es una excelente opción en el tratamiento de la lumbalgia inespecífica, lo que resulta en la promoción de la salud y prevención de este padecimiento para individuos asintomáticos. Nivel de evidencia II, Revisión sistemática de Estudios de nivel II o Nivel I con resultados discrepantes.

Analysis of Motor Behavior based on Recurrence Analysis in Adults with Autism Spectrum and Neurotypicals in a Dynamic Balance Task: a pilot study / Análisis del Comportamiento Motor basado en el Análisis de Recurrencia en Adultos con Espectro Autista y Neurotípicos en una Tarea de Equilibrio Dinámico: un estudio piloto / Análise do Comportamento Motor com base na Análise de Recorrência em Adultos com Espectro deAutismo e Neurotípicos numa Tarefa de Equilíbrio Dinâmico: um estudo piloto

Introduction: Autism spectrum disorders (ASD) refers to a range of neurodevelopmental disorders with deficits in postural control (PC), motor development and coordination. The PC deficit appears to be persistent across the spectrum and can limit the acquisition of new motor skills with severe consequences in life’s’ quality. Objectives: i) to verify if the nonlinear techniques can identify the local recurrence pattern in the phase space of the PC, in individuals with ASD, ii) to compare the PC between ASD and neurotypical individuals, during a task of dynamic rotation balance. Methods: six male adult individuals, three autistic and three neurotypicals, performed a dynamic balance task, where angular velocity data was collected from the trunk. Results: Despite the inexistence of significant differences, autistic adults revealed, for all planes of movement, higher mean values of recurrence, periodicity, stability (except for the maximum line in the transversal plane), complexity and intermittence; differences that were visually confirmed by observingthe recurrence graphs. Autistic participants also revealing lower mean values of Lyapunov exponent, meaning less divergency and variability than the neurotypicals. Conclusions: the autistic’s postural control strategy of a greater periodicity, stability and a lower divergence and variability, may result from less plasticity in the ability to adjust to momentary states of postural imbalance. This strategy could be linked to the autistic’s stereotypical behavior of continuously cyclical movements. However, this does not result in greater variability in movement, but less variability. Given the neuro-motor difficulty of these autistic adults in producing varied ranges of motion, it is recommended to introduce dynamic balance activities, starting with reduced levels of postural stability disturbance. (AU)

Introducción: Los trastornos del espectro autista (TEA) se refieren a una serie de trastornos del neurodesarrollo con déficits en el control postural (CP), el desarrollo motor y la coordinación. El déficit de CP parece estar muy extendido en todo el espectro y puede limitar la adquisición de nuevas habilidades motoras con graves consecuencias en la calidad de vida. Objetivos: i) verificar si las técnicas no lineales identifican el patrón de recurrencia local en el espacio de fase de la CP en individuos con TEA, ii) comparar la CP entre individuos con TEA y neuro típico, durante una tarea de equilibrio de rotación dinámica. Métodos: seis individuos adultos del sexo masculino, tres autistas y tres neuro típico, realizaron una tarea de equilibrio dinámico, donde se recolectaron datos sobre la velocidad angular del tronco. Resultados: A pesar de la ausencia de diferencias significativas, los adultos autistas mostraron, para todos los planos de movimiento, valores medios más altos para la recurrencia, la periodicidad, la estabilidad (excepto para la línea máxima en el plano transversal), la complejidad y la intermitencia; estas diferencias se confirmaron visualmente al observar los gráficos de recurrencia. Autistas también revelaron valores medios más bajos del exponente de Lyapunov, lo que significa menos divergencia y variabilidad en comparación con los neurotípicos. Conclusiones: La estrategia de control postural de los autistas basada en mayor periodicidad, estabilidad y menor divergencia y variabilidad en el control del equilibrio puede resultar de una menor plasticidad en la capacidad de adaptación a estados momentáneos de desequilibrio postural. (AU)

Introdução: Os transtornos do espectro do autismo (TEA) referem-se a uma gama de transtornos no neuro desenvolvimento com déficits nocontrole postural (CP), desenvolvimento motor e coordenação. O déficit no CP parece ser generalizado em todo o espectro e pode limitar a aquisição de novas habilidades motoras com graves consequências na qualidade de vida. Objetivos: i) verificar se as técnicas não lineares identificam o padrão de recorrência local no espaço de fase do CP em indivíduos com TEA, ii) comparar o CP entre indivíduos com TEA e neuro típicos, durante uma tarefa de equilíbrio dinâmico de rotação. Métodos: seis indivíduos adultos do sexo masculino, três autistas e três neuro típicos, realizaram uma tarefa de equilíbrio dinâmico, onde foram recolhidos dados da velocidade angular do tronco. Resultados: Apesar da inexistência de diferenças significativas, os adultos autistas revelaram, para todos os planos de movimento, valores médios superiores de recorrência, periodicidade, estabilidade (exceto na linha máxima no plano transversal), complexidade e intermitência; diferenças estas confirmadas visualmente pela observação dos gráficos derecorrência. Os autistas revelaram ainda valores médios mais baixos do expoente de Lyapunov, significando menor divergência e variabilidade em comparação com os neurotípicos. Conclusões: A estratégia de controle postural dos autistas baseada em maior periodicidade, estabilidade e menor divergência e variabilidade no controle do equilíbrio pode resultar de uma menor plasticidade na capacidade de se ajustar a estados momentâneos de desequilíbrio postural. Esta estratégia pode estar ligada ao comportamento estereotipado dos autistas de realização contínua de movimentos cíclicos. No entanto, isso não resulta em maior variabilidade no movimento, mas em menor variabilidade. (AU)

Learning to Cycle: Are Physical Activity and Birth Order Related to the Age of Learning How to Ride a Bicycle?

The present article aimed to verify whether the age at which children learn to ride a bicycle is related to their physical activity or birth order. Data were collected from an online structured survey between November 2019 and June 2020. A total of 8614 responses were obtained from 22 countries. The results reveal significant differences in learning age depending on the frequency of physical activity (F(5, 7235) = 35.12, p < 0.001, ηp2 = 0.24). People who engaged in physical activity less than twice a month learned to cycle later (M = 7.5 ± 5.3 years) than people who engaged in physical activity on a daily basis (M = 5.7 ± 2.2 years) (p < 0.001). There were also significant differences in learning age according to birth order (F(2, 3008) = 7.31, p = 0.00, ηp2 = 0.005). Only children had the highest learning age (M = 5.5 ± 2.4 years), whereas those who were born last had the lowest, (M = 5.1 ± 1.9 years) (p = 0.013). Creating opportunities for children to be engaged in play and physical activity and social modulation through their older siblings seem to be key conditions to encourage children to learn how to ride a bicycle from a young age and to foster their motor development.

Effect of Aging on the Lower Limb Kinematics in Karate Practitioners: Comparing Athletes and Their Senseis.

With the life expectancy increasing, older adult population has gained the attention of many researchers. Aging is known to lead to a general decline in bodily functions, which affect the quality of life. The aim of this study was to analyze how the aging process affects veteran active karate practitioners, in the kinematic and temporal structure of the frontal kick. Nine black belt karate practitioners over 50 years old and 24 black belt karate practitioners, aged between 20 and 30 years old, all male, performed the frontal kick mae-geri. Results showed that knee is the structure that holds most differences between young and veterans, both for linear and for angular variables during the mae-geri performance. Statistical differences were found in linear velocity for the knee; linear acceleration of the knee, hip, and RASIS; maximum angular velocity for knee and hip; maximum angular acceleration for ankle and hip; and in the range of motion of knee. The temporal variables show differences, between groups, in maximum linear velocity, maximum linear acceleration, and maximum angular acceleration. However, no differences were found between groups for the time before contact in the maximum linear and angular acceleration, which allow us to remark both the effects of the aging process and the effect of training. This study corroborates the ability of older people to achieve benefits from sports practice, achieving higher efficiency than the younger adults in task execution, but using different motor control strategies.

Effect of 6-month community-based exercise interventions on gait and functional fitness of an older population: a quasi-experimental study.

BACKGROUND: Gait ability in older adults has been associated with independent living, increased survival rates, fall prevention, and quality of life. There are inconsistent findings regarding the effects of exercise interventions in the maintenance of gait parameters. OBJECTIVES: The aim of the study was to analyze the effects of a community-based periodized exercise intervention on the improvement of gait parameters and functional fitness in an older adult group compared with a non-periodized program. METHODS: A quasi-experimental study with follow-up was performed in a periodized exercise group (N=15) and in a non-periodized exercise group (N=13). The primary outcomes were plantar pressure gait parameters, and the secondary outcomes were physical activity, aerobic endurance, lower limb strength, agility, and balance. These variables were recorded at baseline and after 6 months of intervention. RESULTS: Both programs were tailored to older adults' functional fitness level and proved to be effective in reducing the age-related decline regarding functional fitness and gait parameters. Gait parameters were sensitive to both the exercise interventions. CONCLUSION: These exercise protocols can be used by exercise professionals in prescribing community exercise programs, as well as by health professionals in promoting active aging.

Three-dimensional kinematic adaptations of gait throughout pregnancy and post-partum.

PURPOSE: The kinematic analysis of gait during pregnancy provides more information about the anatomical changes and contributes to exercise and rehabilitation prescription. The purposes were to describe and quantify the spatial, temporal and kinematic parameters in the joints of the lower limb during gait at the end of the first, second and third trimesters of pregnancy and in the postpartum period. METHODS: A three-dimensional analysis was performed in eleven pregnant women. Repeated measures ANOVA was performed for comparisons between periods. RESULTS: The longitudinal effect of pregnancy was not observed in spatial and temporal parameters. In joint kinematics the effect of pregnancy was observed in all joints for the three planes of motion. The hip joint and pelvis are the structures with more changes, and the results point to an increase in the anterior tilt of the pelvis as the pregnancy progresses, as well as a decrease of the amplitudes of the hip joint. The results suggested that pregnant women need to maintain the stability of the body, and become more efficient in locomotion. CONCLUSIONS: In general, the results retrieve the values from the beginning of pregnancy, indicating that the body was self-organized in order to overcome the morphological and physiological changes which women suffer during pregnancy, indicating that they have the ability to adapt depending on the demands, and after the effect of pregnancy is over, they return to values similar to those found in early pregnancy.

Influence of Body Composition on Gait Kinetics throughout Pregnancy and Postpartum Period.

Pregnancy leads to several changes in body composition and morphology of women. It is not clear whether the biomechanical changes occurring in this period are due exclusively to body composition and size or to other physiological factors. The purpose was to quantify the morphology and body composition of women throughout pregnancy and in the postpartum period and identify the contribution of these parameters on the lower limb joints kinetic during gait. Eleven women were assessed longitudinally, regarding anthropometric, body composition, and kinetic parameters of gait. Body composition and body dimensions showed a significant increase during pregnancy and a decrease in the postpartum period. In the postpartum period, body composition was similar to the 1st trimester, except for triceps skinfold, total calf area, and body mass index, with higher results than at the beginning of pregnancy. Regression models were developed to predict women's internal loading through anthropometric variables. Four models include variables associated with the amount of fat; four models include variables related to overall body weight; three models include fat-free mass; one model includes the shape of the trunk as a predictor variable. Changes in maternal body composition and morphology largely determine kinetic dynamics of the joints in pregnant women.

Three-Dimensional Kinetic Adaptations of Gait throughout Pregnancy and Postpartum.

Biomechanical adaptations that occur during pregnancy can lead to changes on gait pattern. Nevertheless, these adaptations of gait are still not fully understood. The purpose was to determine the effect of pregnancy on the biomechanical pattern of walking, regarding the kinetic parameters. A three-dimensional analysis was performed in eleven participants. The kinetic parameters in the joints of the lower limb during gait were compared at the end of the first, second, and third trimesters of pregnancy and in the postpartum period, in healthy pregnant women. The main results showed a reduction in the normalized vertical reaction forces, throughout pregnancy, particularly the third peak. Pregnant women showed, during most of the stance phase, medial reaction forces as a motor response to promote the body stability. Bilateral changes were observed in hip joint, with a decrease in the participation of the hip extensors and in the eccentric contraction of hip flexors. In ankle joint a decrease in the participation of ankle plantar flexors was found. In conclusion, the overall results point to biomechanical adjustments that showed a decrease of the mechanical load of women throughout pregnancy, with exception for few unilateral changes of hip joint moments.

Comparison between overweight due to pregnancy and due to added weight to simulate body mass distribution in pregnancy.

The assessment of biomechanical loading in the musculoskeletal system of the pregnant women is particularly interesting since they are subject to morphological, physiological and hormonal changes, which may lead to adaptations in gait. The purpose of this study was to analyze the effect of the increased mass in the trunk associated to pregnancy on the lower limb and pelvis, during walking, on temporal-distance parameters, joint range of motion and moments of force, by comparing a pregnant women group to a non-pregnant group, and to this group while carrying a 5 kg additional load located in the abdomen and breasts during walking, to understand which gait adaptations may be more related with the increased trunk mass, or if may be more associated with other factors such as the girth of the thigh. The subjects performed a previous 12 min training adaption to the added load. To calculate ankle, knee and hip joint angles and moments of force, a three-dimensional biomechanical model was developed. The inverse dynamics method was used to estimate net joint moments of force. The increased mass of the anterior trunk associated with second trimester of pregnancy may influence some gait variables such as the left step time, left and right stance times, double limb support time, maximum hip extension, maximum pelvic right obliquity, pelvic obliquity range of motion, maximum transversal left rotation and peak hip flexion moments of force.

Biomechanics of gait during pregnancy.

INTRODUCTION: During pregnancy women experience several changes in the body's physiology, morphology, and hormonal system. These changes may affect the balance and body stability and can cause discomfort and pain. The adaptations of the musculoskeletal system due to morphological changes during pregnancy are not fully understood. Few studies clarify the biomechanical changes of gait that occur during pregnancy and in postpartum period. PURPOSES: The purpose of this review was to analyze the available evidence on the biomechanical adaptations of gait that occur throughout pregnancy and in postpartum period, specifically with regard to the temporal, spatial, kinematic, and kinetic parameters of gait. METHODS: Three databases were searched and 9 studies with a follow-up design were retrieved for analysis. RESULTS: Most studies performed temporal, spatial, and kinematic analysis. Only three studies performed kinetic analysis. CONCLUSION. The adaptation strategies to the anatomical and physiological changes throughout pregnancy are still unclear, particularly in a longitudinal perspective and regarding kinetic parameters.

Kinematic analysis of gait in the second and third trimesters of pregnancy.

The kinematic analysis of gait during pregnancy provides more information about the anatomical changes and contributes to exercise and rehabilitation prescription. The purposes were to quantify the lower limb kinematics of gait and to compare it between the second and third trimesters of pregnancy and with a control group. A three-dimensional analysis was performed in twenty-two pregnant women and twelve nonpregnant. Repeated Measures and Manova tests were performed for comparisons between trimesters and between pregnant and controls. The walking speed, stride width, right-/left-step time, cycle time and time of support, and flight phases remain unchanged between trimesters and between pregnant and controls. Stride and right-/left-step lengths decreased between trimesters. Double limb support time increased between trimesters, and it increased when compared with controls. Joint kinematics showed a significant decrease of right-hip extension and adduction during stance phase between trimesters and when compared with controls. Also, an increase in left-knee flexion and a decrease in right-ankle plantarflexion were found between trimesters. The results suggested that pregnant women need to maintain greater stability of body and to become more efficient in locomotion. Further data from the beginning of pregnancy anthropometric data may contribute to the analysis.