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Small-sided games are used to improve tactical-technical and physical performances in team sports. This study compared the physical, physiological, and tactical-technical responses during 3 versus 3 basketball small-sided games performed in full and half-court: numerical equality (3 vs. 3), numerical superiority (4 vs. 3), and with a non-scorer floater (3 vs. 3 + 1). A total of 45 U-14 and U-15 male athletes participated in the study. They were divided into three-player teams and played one 4-minute bout of each small-sided game type. Heart rate and the time spent in four acceleration zones (0.0–0.5, 0.5–1.0, 1.0–1.5, and 1.5–2.0 g) were recorded using heart rate monitors and triaxial accelerometers. Small-sided games were filmed for the analysis of tactical-technical behavior. Results showed a higher frequency of space creation without the ball, and a mean number of passes per offense in the formats 4 versus 3 and 3 versus 3 + 1, and a lower frequency of space creation with the ball dribbled in 3 versus 3 + 1 compared with 3 versus 3. Physical and physiological responses were higher in the full-court regardless of format and in numerical equality regardless of court area; only the time spent in the highest acceleration zone was higher in half-court small-sided games. We concluded that additional players increase group tactical actions and decrease physical and physiological responses in 3 versus 3 basketball small-sided games.

We examined the association between 50 m freestyle performance (50FS) and average speed (AS), peak speed (PS), minimum speed (MS) and intracyclic speed variation (ISV) and compared the speed curves from swimmers with different performance levels using functional analysis of variance (FANOVA). Fourteen male swimmers (50FS: 22.50 ± 0.58 s) performed a maximal sprint with a speedometer and AS, PS, MS, and IVV were assessed for correlational analysis. 50FS were obtained in official competitions. Swimmers were assigned to three groups based on actual 50FS: G21 (n = 2, 21.99 ± 0.04 s), G22 (n = 6, 22.82 ± 0.10 s) or G23 (n = 6, 23.55 ± 0.18 s). FANOVA compared the average curves. 50FS correlated to AS (r = −0.781, p = 0.001) and PS (ρ = −0.766, p = 0.001), but not to MS (r = −0.185, p = 0.527) or IVV (r = −0.323, p = 0.259). FANOVA showed that faster swimmers achieved higher PS and stayed longer at the upper part of the curve. 50FS performance is related to average and peak speed assessed with the speedometer. Swimmers should seek techniques to maintain the speed at the upper part of the curve as long as possible.

This study followed a cross-sectional design and aimed to compare the offensive and defensive tactical-technical actions and the physical and physiological responses between four 3vs.3 basketball small-sided games (SSGs) played on the half-court: with regular rules (3vs.3REGULAR), with defensive pressure (3vs.3DEFPRESS), with the close-shot rule (3vs.3CLOSESHOT), and with offensive numerical superiority (4vs.3). Fifty-one U-14 and U-15 male athletes participated in the study. They were divided into 3-player teams and played one 4-min bout of each SSG type. Heart rate and the time spent in four acceleration zones (0.0–0.5, 0.5–1.0, 1.0–1.5, and 1.5–2.0 g) were recorded using heart rate monitors and triaxial accelerometers. SSGs were filmed for the analysis of Space Creation Dynamics and defensive tactical-technical actions. Results showed a higher frequency of space creation without the ball and a mean number of passes per offense in the 4vs.3, with this SSG showing higher offensive performance than the 3vs.3CLOSESHOT (large effect sizes). Defensive behavior was significantly impacted by all rules: in general, 4vs.3 presented the highest frequency of closeouts, 3vs.3DEFPRESS increased the frequency of close off-ball marking and the 3vs.3CLOSESHOT increased the frequency of double-teaming, all differences presenting large effect sizes. Heart rate and the time spent in moderate and high accelerations (zones 2 and 3) were the highest with defensive pressure and the lowest with numerical superiority; heart rate and accelerations in the close-shot rule are higher than in numerical superiority but similar to the 3vs.3REGULAR. We concluded that the SSGs investigated in this study can stimulate different offensive and defensive actions and be used to develop the performance of basketball athletes.

Background To investigate the effect of different fixation strategies of the intramedullary interlocking nail (IIN) on the mechanical behavior of a polymeric implant applied for femoral fracture fixation in calves, and to evaluate the performance of a glass fiber-reinforced polymer applied in a bovine femoral fracture reduction system, five Holstein male animals with a mean weight (±SD) of 62.8 ± 20.4 kg and aged 74 ± 15 were used to generate biomechanical parameters for this study. Twelve models of the fractured bovine femur, simulating a simple oblique fracture, were developed for use during the simulations. The models were divided into three groups, with each group of four models being associated with a different fixation strategy. Models were used to simulate the loading conditions corresponding to a calf in the transition (decubitus position to static position) condition. The maximum stresses found in each set (bone/implant) were compared with the reference stresses of each nail material. Results Maximum implant stresses were found in the screws and at the interface between the screw and the nail. The performance of implants was influenced by the material and fixation strategy, which can be confirmed by the stress values found in the set. The analysis indicated that the composite nail is able to withstand the loading demands in all fixation strategies. Conclusions The finite element analysis (FEA) demonstrated that all polymeric materials analyzed provided sufficient resistance to withstand the loading forces imposed to the femur when an adequate blocking strategy was applied.

Pedaling asymmetry is claimed as a factor of influence on injury and performance. However, the evidence is still controversial. Most previous studies determined peak torque asymmetries, which in our understanding does not consider the pattern of movement like torque profiles. Here we demonstrate that asymmetries in pedaling torque at different exercise intensities can be better described when the torque profiles are considered using functional analysis of variance than when only the peak values are analyzed. We compared peak torques and torque curves recorded while cyclists pedaled at submaximal intensities of 60%, 80%, and 95% of the maximal power output and compared data between the preferred and non-preferred legs. ANOVA showed symmetry or rather no difference in the amount of peak torque between legs, regardless of pedaling intensity. FANOVA, on the other hand, revealed significant asymmetries between legs, regardless of cycling intensity, apparently for different sections of the cycle, however, not for peak torque, either. We conclude that pedaling asymmetry cannot be quantified solely by peak torques and considering the analysis of the entire movement cycle can more accurately reflect the biomechanical movement pattern. Therefore, FANOVA data analysis could be an alternative to identify asymmetries. A novel approach as described here might be useful when combining kinetics assessment with other approaches like EMG and kinematics and help to better understand the role of pedaling asymmetries for performance and injury risks.

Asymmetries compromise performance in powerlifting and Paralympic powerlifting, but its quantification can be complex. Previous studies consider average or peak values to quantify asymmetries, however this approach does not consider the pattern of movement like velocity profiles. Here we demonstrate that conducting a functional analysis of variance (FANOVA) permits to quantify asymmetries in bench press performance by Paralympic powerlifting at different submaximal intensities. Kinematic data were collected from 10 Paralympic powerlifting athletes performing in bench press at submaximal intensities (50% and 90% of the one-repetition maximum). Linear velocity was quantified considering mean values and the entire waveform. Mean values were compared by analysis of variance (ANOVA) and the waveforms were compared by FANOVA. FANOVA identified asymmetry profiles that ANOVA did not recognize at the highest intensity, which is the closest to a competition. This way, FANOVA can bring advantages to the analysis of competitive performance. FANOVA data analysis identifies asymmetries at higher intensity of effort considering the whole pattern of movement. Therefore, we consider that the FANOVA's approach may benefit the biomechanical assessment of the Paralympic powerlifting.

O tratamento de fraturas ósseas são procedimentos corriqueiros na clínica ortopédica humana e veterinária. As fraturas em ossos longos (p. ex. fêmur, úmero, tíbia) ocorrem com frequência tanto em humanos como em animais domésticos e demandam técnicas específicas de estabilização. Hastes intramedulares, confeccionadas com materiais biocompatíveis, têm sido reconhecidas como adequadas no tratamento de fraturas de ossos longos. O desenvolvimento de artefatos, que apresentem as necessárias características de biocompatibilidade e resistência mecânica às demandas de estabilização óssea, exige o entendimento do comportamento biomecânico do sistema músculo-esquelético. Este trabalho investigou o efeito de diferentes estratégias de fixação, de uma haste intramedular, sobre o comportamento mecânico de um implante polimérico aplicado na redução de uma fratura femoral em bezerros. Avaliou-se ainda o desempenho de quatro materiais poliméricos utilizados para a fabricação das hastes intramedulares. Foram utilizados neste estudo cinco animais machos Holstein com peso médio (± DP) de 62,8 ± 20,4 kgf e idade 74 ± 15 dias. Com base no modelo sólido do fêmur, foram construídos dezesseis modelos para simular uma fratura simples oblíqua. Os modelos foram divididos em quatro grupos, sendo cada grupo de quatro modelos associado a uma estratégia de fixação diferente. Os modelos foram testados sob a mesma condição de carregamento que simulavam um bezerro na condição de transição (posição de decúbito para a posição estática). As tensões máximas do osso e do implante foram comparadas com as tensões de escoamento e ruptura dos materiais utilizados para a construção das hastes (poliacetal, polipropileno, poliamida VI e material compósito com matriz de poliéster reforçado com fibra de vidro). As maiores tensões no implante foram encontradas nos parafusos e na interface entre o parafuso e a haste. O desempenho dos implantes foi influenciado pelo material e pela estratégia de fixação. As análises do modelo de elementos finitos demonstraram que todos os materiais poliméricos analisados forneceram resistência suficiente para tolerar as cargas impostas ao fêmur, quando uma estratégia de fixação adequada foi aplicada The treatment and the reduction of bone fractures are usual procedures in human and veterinary orthopedic clinics. Fractures of long bones (e.g., femur, humerus, tibia) occur frequently both in humans and domestic large animals, requiring specific techniques of stabilization. Intramedullary nails, made from biocompatible materials, have been recognized as suitable for the treatment of long bone fractures. The development of prosthesis, presenting the necessary biocompatibility and mechanical strength to support bone stabilization demands, requires the understanding of the biomechanical behavior of the musculoskeletal system. To investigate the effect of different fixation strategies of the intramedullary interlocking nail (IIN) on the mechanical behavior of a polymeric implant applied for femoral fracture fixation in calves. It was also evaluated the performance of four polymeric materials used for the manufacture of intramedullary nails. Five Holstein male animals with a mean weight (± SD) of 62.8 ± 20.4 kgf and aged 74 ± 15 days were used in this study. Based on the solid model of the femur, sixteen models were built to simulate an oblique simple fracture. The models were divided into four groups, with each group of four models being associated with a different fixation strategy. Models were tested under the same loading condition that simulated a calf in the transition (decubitus position to static position) condition. Maximum bone and implant stresses were compared to yield and rupture stresses of specific materials (polyacetal, polypropylene, polyamide VI and a glass fiber-reinforced polymer). The largest stresses in the implant were found in the screws and at the interface between the screw and the nail. The performance of implants was influenced by the material and fixation strategy. The finite element method (FEM) model analyses demonstrated that all polymeric materials analyzed provided sufficient resistance to tolerate the loading forces imposed on the femur when an adequate fixation strategy was applied.

Considering the hypothesis that laminitic horses display changes in the kinematics of their forelimbs and clog type orthopedic devices can be beneficial in such cases, the objectives of this study were to compare the stride pattern of healthy horses versus that of horses with chronic laminitis and to assess the kinematic effects of three types of clog shoes on the stride of laminitic horses. Six healthy and six laminitic mares were subjected to a kinematic evaluation at a walk. The horses with laminitis were evaluated before and after the use of three different models of clog type orthopedic shoes on the hooves of both their forelimbs. The treatment types that were administered were the application of no shoes, wooden shoes, leather and ethylene-vinyl acetate (EVA) shoes, and wooden and EVA shoes. The horses with laminitis have a stride length that is reduced by 11% (P = 0.03), and in the swing phase, by 18% (P = 0.004), and the relative stance phase of each limb is prolonged by 6% (P = 0.02) when compared with the healthy group. However, values associated with the stride duration, stance phase duration, breakover duration, speed, and frequency were not significantly different among the laminitic groups. Further, no statistical differences were found in the comparison of the outcomes among the treatments administered to the horses with laminitis, except in their stride length, which was longer in the horses shod with wooden clogs when compared with in the unshod laminitic horses (P = 0.04). It was concluded that horses with stable chronic laminitis display changes in the kinematics of their forelimbs while walking. Immediate and remarkable beneficial effects were not observed with the use of all the types of orthoses; however, the wooden clog resulted in a significant improvement in the length of the stride. Further studies are needed to verify the prolonged effects of clog shoe-type ortheses in the different phases of equine laminitis.

The aim of this study was to present a new training algorithm using artificial neural networks called multi-objective least absolute shrinkage and selection operator (MOBJ-LASSO) applied to the classification of dynamic gait patterns. The movement pattern is identified by 20 characteristics from the three components of the ground reaction force which are used as input information for the neural networks in gender-specific gait classification. The classification performance between MOBJ-LASSO (97.4%) and multi-objective algorithm (MOBJ) (97.1%) is similar, but the MOBJ-LASSO algorithm achieved more improved results than the MOBJ because it is able to eliminate the inputs and automatically select the parameters of the neural network. Thus, it is an effective tool for data mining using neural networks. From 20 inputs used for training, MOBJ-LASSO selected the first and second peaks of the vertical force and the force peak in the antero-posterior direction as the variables that classify the gait patterns of the different genders.

Treatment of long bone fractures in bovines has been an objective of recent veterinary research. Accurate estimates of body segment inertial parameters (BSIP) play an important role in an appropriate prosthesis development. The aim of the present study is to develop a geometric model of bovine pelvic limb based on the mass distribution properties. Computer tomography images were used to obtain a computational model of bovine limb. This model provided information for geometric model construction. Measures of segmental mass, positions of segmental center of mass (CoM), and longitudinal moment of inertia (MoI zz ) of segments of the right pelvic limb were estimated based on the geometric model. These estimates were compared with the computational model’s measurements and showed consistent accuracy. The segment mass decreased with distance from the pelvis with mean relative error (Er) less than −5.87 ± 1.2%, as did the segment MoI zz with Er(%) less than −16.40 ± 7.61% for segments predominantly consisting of bony tissue. The MoI zz was overestimated for segment with more soft tissue with Er(%) = 10.95 ± 19.08. The CoM zz was located 36–50% distal to the proximal segment end. The more proximal segment showed the largest Er(%) = −11.21 ± 2.41%, while the more distal showed the smallest Er(%) = 1.82 ± 0.87% for CoM zz . This study not only presents a technique that may be applied to other body segments, but also provides insight into bovine musculoskeletal system necessary to improve the biomechanical models applied to dynamic analysis of bovine movement.

Lower extremity kinetic data during walking of 12 people with chronic poststroke were reanalyzed, using functional analysis of variance (FANOVA). To perform the FANOVA, the whole curve is represented by a mathematical function, which spans the whole gait cycle and avoids the need to identify isolated points, as required for traditional parametric analyses of variance (ANOVA). The power variables at the ankle, knee, and hip joints, in the sagittal plane, were compared between two conditions: With and without walking sticks at comfortable and fast speeds. For the ankle joint, FANOVA demonstrated increases in plantar flexion power generation during 60–80% of the gait cycle between fast and comfortable speeds with the use of walking sticks. For the knee joint, the use of walking sticks resulted in increases in the knee extension power generation during 10–30% of the gait cycle. During both speeds, the use of walking sticks resulted in increased power generation by the hip extensors and flexors during 10–30% and 40–70% of the gait cycle, respectively. These findings demonstrated the benefits of applying the FANOVA approach to improve the knowledge regarding the effects of walking sticks on gait biomechanics and encourage its use within other clinical contexts.

Este trabalho visou comparar a influência de dois padrões de entrada, coeficientes de Fourier versus Legendre, sobre o desempenho de classificação de padrões da marcha. Para distinguir a marcha de indivíduos, foram aplicados aos padrões de entrada, o método dos Quadrados Mínimos (MQ) e o Least Absolute Shrinkage and Selector Operator (LASSO). O desempenho dos métodos foi testado para identificar marcha descalça e marcha calçada de quarenta e três indivíduos, 19 homens e 24 mulheres, com idade média de 24,8 anos. Os indivíduos caminharam sobre uma plataforma de força à velocidade auto-selecionada e de 1,3 m.s-1. Cada indivíduo realizou 80 (oitenta) tentativas, sendo 40 (quarenta) descalço e 40 (quarenta) utilizando seu próprio calçado. A componente vertical da força de reação do solo foi registrada à freqüência de amostragem de 1kHz. Os coeficientes de Legendre e de Fourier foram utilizados como dados de entrada para o classificador de MQ. Os resultados, utilizando-se a componente vertical (Fy), mostram que, para a situação (marcha descalça versus marcha calçada), as taxas de classificação foram maiores do que 99,0% para os dois diferentes tipos de dados de entrada. A taxa de classificação, ao utilizar a componente vertical (Fy) com a aplicação do LASSO foi maior do que 98,0%, com os coeficientes de Fourier e maior do que 99% quando foram utilizados os coeficientes de Legendre como parâmetros de entrada. O número de coeficientes necessários, para atingir essas taxas de classificação, foi menor com o LASSO, comparado ao número de coeficientes utilizados pelo método dos MQ. The influence of different input data (Fourier versus Legendrecoefficients), on gait patterns classification performance were analyzed byOrdinary Least Squared Method (OLS) and Least Absolute Shrinkage andSelector Operator (LASSO). The classification performance was tested inbarefoot gait and shod gait of forty-three individuals, 19 men and 24 women, 24,8 years old, walking on a force platform at a self-determined velocity and 1,3 m.s-1. Every individual performed 40 trials barefoot and 40 trials with their own shoe wear. The vertical component of the ground reaction force was registered at frequency of 1 kHz. The Legendre coefficients and the Fourier coefficients were applied as a standard entry for the OLS and the LASSO. The OLS analysis of vertical component of ground reaction force (Fy), suggested the recognition rates (e.g. barefoot gait versus shod gait) were higher than 99,0% for both types of input data. The recognition rate with the Lasso, for vertical component of ground reaction force (Fy), was higher than 98,0% using Fourier coefficients and higher than 99% for Legendre coefficients. The coefficient number used by the LASSO is smaller than OLS coefficient number.