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Mulching (crushing capoeira) is an alternative system for the use of fire for cultivation in the Northern region of Brazil. Cowpea is c onsidered an important food crop in this region; however, weeds might limit its productivity. This study aimed to evaluate the population dynamics of weeds and the productivity of cowpea with different habit of growth inoculated with Bradyrhizobium sp in m ulching. The experiment was carried out in randomized blocks with the cultivars BRS Guariba and BR 17 Gurgueia, w ith and without inoculation of Bradyrhizobium sp and nitrogen fertilization as a control. Twenty seven species and three genera of weeds were i dentified, distributed into 12 botanical families in the BRS Guariba cultivar and 25 species in ten families in B R 17 Gurgueia cultivar. The results revealed that the significative species were Vismia guianensis (Aubl.) Cyperus sp, Scleria melaleuca Rchb. ex Schltdl. & Cham, and Spermacoce verticillata L. Inoculation with Bradyrhizobium sp reduced the infestati on of the most important species and presented higher productivity (1965.09 kg ha 1 ) than the treatment without inoculation (987.14 kg ha 1 T he growth habit of cowpea cultivars in mulching (crushing capoeira) system did not affect crop yield, but longer studies are needed to validate the information obtained. Made available in DSpace on 2022-05-04T14:12:45Z (GMT). No. of bitstreams: 1 Weed-Dynamics-and-Yield-of-Cowpea-Inoculated.pdf: 928916 bytes, checksum: 3464f85753ceb2b2db1a239c72e3390e (MD5) Previous issue date: 2022

Made available in DSpace on 2020-11-18T09:12:34Z (GMT). No. of bitstreams: 1 Bovine-chilled-semen-2020.pdf: 103026 bytes, checksum: caf3ac5cb2ffd919af9d012e30a4f8b4 (MD5) Previous issue date: 2020 Physiology of reproduction in male and semen technology. Abstracts 34th Annual Meeting of the Brazilian Embryo Technology Society (SBTE), 13 a 15 de agosto de 2020.

To LEN (Ligue Européenne de Natation) and Spiideo AB for providing the videos. We would like to thank the support of the University of Beira Interior and Santander Universities (Bolsa BIPD/ICI-FCSH-Santander Universidades-UBI/2017) The aim of this study was to examine the performance characteristics of male and female finalists in the 100-m distance at the 2016 European Championships in swimming (long-course-metre). The performances of all 64 (32-males and 32-females) were analysed (8 swimmers per event; Freestyle, Backstroke, Breaststroke and Butterfly). A set of start and turn parameters were analysed. In the start main outcome, male swimmers were faster in Butterfly (5.71 ± 0.14s) and females in Freestyle (6.68 ± 0.28s). In the turn main outcome, male and female swimmers were faster in Freestyle (males: 9.55 ± 0.13s; females: 10.78 ± 0.28s). A significant and strong stroke effect was noted in the start and turn main outcome, in both sexes. In the start plus the turn combined, males and females were faster in Freestyle (males: 15.40 ± 0.20s; females: 17.45 ± 0.54s). The start and the turn combined accounted almost one-third of the total race time in all events, and non-significant differences (p > 0.05) were noted across the four swim strokes. Once this research made evident the high relevance of start and turns, it is suggested that coaches and swimmers should dedicate an expressive portion of the training perfecting these actions To LEN (Ligue Européenne de Natation) and Spiideo AB for providing the videos. We would like to thank the support of the University of Beira Interior and Santander Universities (Bolsa BIPD/ICIFCSH-Santander Universidades-UBI/2017). info:eu-repo/semantics/acceptedVersion

The aims of this study were to assess over a full season: (i) the effect of a combined dry-land strength and conditioning and in-water program on the swimming performance of young swimmers; (ii) the effect of such program on the performance determinants; (iii) the effect of the training periodization designed. A longitudinal research design assessing an age-group of young swimmers over a season was carried out. Methods: Twenty-seven young swimmers (12 boys: 13.55±0.72-y; 15 girls: 13.16±0.93-y; both sexes in Tanner stages 2-3) were evaluated in three moments over 40 weeks. The 100-m freestyle performance, body mass, height, arm span (anthropometrics), stroke frequency, stroke length, swimming velocity, intracyclic swimming velocity (kinematics), stroke index, propelling efficiency (efficiency), squat jump, countermovement jump, and throw velocity (strength and conditioning) were assessed. A cluster analysis was computed to classify the swimmers. For the “talented” swimmers, the performance and all determinants, but the squat and countermovement jumps improved between the first and last evaluation moments. Both in-water and dry-land strength and conditioning features were responsible for the cluster discrimination in each one of the evaluation moments. All three clusters were also characterized by a mix of technical and strength & conditioning features. This highlights swimming performance as a holistic phenomenon (i.e. multiple determinants) where shifting occur in the interplay among the performance determinant according to the training periodization. info:eu-repo/semantics/publishedVersion

Problem Statement: The aim of this study was to compare the ball velocity in different kicking conditions with dominant and non-dominant leg in junior soccer players.Approach: Sixteen junior soccer players (age 17.6±0.6yr, height 1.76±0.06m, and weight 67.9±5.2kg) participated in this study. All participants kicked a soccer ball three times in seven conditions with the dominant and non-dominant leg. 1) Kicking the ball from 11m straight forwards, 2 and 3) kicking the ball from 11m to the left and right side of the goal, 4 and 5) kicking the ball straight forwards from 11m after a pass from the left and right side, 6 and 7) kicking the ball straight forwards from 11m after a pass that came from a diagonal position (45º) from the left and right side. The highest ball velocity was used for analysis.Results: Significant differences were found in ball velocity between the dominant and non-dominant leg in all conditions (p

Introduction In competitive swimming, performance relies in the good combination of force and technique. The relative contribution of each of these components is still a controversial issue. Therefore, the aim of this study was to verify if force metrics obtained through tethered swimming can be explanatory of free swimming performance. Methods 22 age-group swimmers (male n=14, age: 14.6±1.2years of age, body mass: 53.1±9.0kg, height: 1.66±0.1m; female n=8, age: 13.9±2.1years of age, body mass: 46.3±9.2kg, height: 1.57±0.1m) took part in the study. Each participant performed a 30 s maximal front crawl tethered swimming test (described in detail by Morouço et. al, 2011). After normality assumption checked, force metrics (average force – Favg; maximum force – Fmax; and impulse of force – Fimp) were correlated with 50m in-water maximal bout performance (t50). Results Both in male and female swimmers Favg presented strong negative correlations with t50 (r=-0.81 and r=-0.95; p

Swimming performance differences are notorious among male and female post-puberty swimmers. Previous studies point that, in adolescence, boys are taller and heavier than girls; taking advantage in swimming performance with that anthropometric difference (Morouço et al., 2012). Therefore, the aim of this study was to identify possible differences between performance (personal best at 50m freestyle) and parameters obtained in tethered swimming tests (force and impulse), between genders. Methods One group of 14 male adolescent swimmers (age: 14.6±1.2years of age, body mass: 53.1±9.0kg, height: 1.66±0.1m, arm span: 1.69±0.1m) and other of 8 female adolescent swimmers (age: 13.9±2.1years of age, body mass: 46.3±9.2kg, height: 1.57±0.1m, arm span: 1.59±0.1m) took part in the study. Each participant performed a 30 s maximal front crawl tethered swimming test (described in detail by Morouço et. al, 2011) and a 50m in-water maximal bout. After normality assumption checked, speed in 50m in-water maximal bout (s50) and force metrics (average force – Favg; maximum force – Fmax; and impulse of force – Fimp) were assessed for each group. Results 50m swimming speed was significantly higher for the males group comparing with females cohort (1.69±0.11 vs. 1.52±0.13 m/s, p=0.004; respectively). The same superiority was observed in tethered swimming metrics (Favg: 78.1±17.1 vs. 56.0±14.5 N, p=0.006; Fmax: 200.8±51.4 vs. 141.4±35.48 N, p=0.009; Fimp: 74.7±15.6 vs. 52.8±16.3 N.s, p=0.006; respectively). No differences were found in body mass, height and arm span (p>0.05). Discussion It is assumed that body mass and height differences among males and females intensively increase after puberty (Kraemer et al., 1989). Thus, it is pointed that at these ages males are capable to produce more strength (Schneider & Meyer, 2005). However, in the present study no anthropometrical differences were noticed, and still performance and force exertion in-water were higher for the males group. These results suggest that other variables, rather than body constitution, should be considered when evaluating adolescent swimmers. The higher values in tethered swimming metrics may imply that male swimmers had higher muscle strength levels and/or a greater capacity to apply propulsive force to water. References Bencke J, Damsgaard R, Saekmose A, Jorgensen P, Jorgensen K, & Klausen K, (2002).Scand J Med Sci Sport. ; 12:171-178. Kraemer WJ, Fry AC, Frykman PN, Conroy B, Hoffman J, (1989) Pediatric Exercise Science, v.1, p.336-350. Morouço P, Vilas-Boas JP, Fernandes R, (2012).Pediatric Exercise Science,v 24, 312-321 Schneider P, Meyer F,(2005).Revista Brasileira de Medicina do Esporte,v.11, p.209-13.

The aim of this study was to compare the speed fluctuation and the drag force in young swimmers between genders. Twenty-three young pubertal swimmers (12 boys and 11 girls) volunteered as subjects. Speed fluctuation was measured using a kinematical mechanical method (i.e., speedo-meter) during a maximal 25-m front crawl bout. Active drag, active drag coefficient and power needed to overcome drag were measured with the velocity perturbation method for another two maximal 25 m front crawl bouts with and without the perturbation device. Passive drag and the passive drag coefficient were estimated using the gliding decay velocity method after a maximal push-off from the wall while being fully immersed. The technique drag index was also assessed as a ratio between active and passive drag. Boys presented meaningfully higher speed fluctuation, active drag, power needed to overcome drag and technique drag index than the girls. There were no significant gender differences for active drag coefficient, passive drag and passive drag coefficient. There were positive and moderate- strong associations between active drag and speed fluctuation when controlling the effects of swim velocity. So, increasing speed fluctuation leads to higher drag force values and those are even higher for boys than for girls.

O meio aquático é um dos ambientes mais ricos e diversos para a estimulação psicomotora de crianças. Os programas de actividades aquáticas na primeira infância têm se voltado de forma crescente para estilos de ensino menos rígidos e formais, com uma maior preponderância da componente lúdica. Comparativamente com as restantes actividades aquáticas de índole educativa, as que se reportam à primeira infância apresentam claramente uma lacuna na apresentação de propostas alternativas e lúdicas para o desenrolar das sessões. Foi objectivo deste trabalho propor uma selecção de jogos aquáticos de índole educativa para serem apresentados num programa de actividades aquáticas na primeira infância tomando em consideração: (i) os conteúdos e progressão pedagógica deste tipo de programas; (ii) os seus objectivos; (iii) os estilos de ensino possíveis de serem implementados e; (iv) a taxionomia dos jogos aquáticos educativos.

Apenas está disponível um resumo

Apenas está disponível um resumo.

Os objetivos deste estudo foram: i) caracterizar o nado submáximo e máximo do ponto de vista cinemático; ii) verificar a influência das variáveis cinemáticas na prova máxima de 200 metros crawl. Nove nadadores de elite nacionais realizaram dois testes: um submáximo, descontínuo de intensidade progressiva; outro máximo, que consistiu em uma simulação de uma prova de 200 m crawl. Foram estudados os parâmetros cinemáticos gerais da mecânica da braçada, a duração de cada fase do ciclo gestual, a velocidade do centro de massa e a variação intracíclica da velocidade horizontal. Verificaram-se diferenças cinemáticas significativas da frequência gestual, velocidade de deslocamento do centro de massa, duração total do ciclo gestual, duração da ação subaquática propulsora e da velocidade do centro de massa na fase de recuperação entre os testes. Identificou-se associações significativas entre o teste máximo e algumas variáveis cinemáticas como a velocidade do centro de massa e índice de nado. Palavras-chave: nado crawl; cinemática; prova submáxima; prova máxima. The main aims of this study were i) to perform a kinematic characterization of sub and maximal swimming speed; ii) to investigate the associations between the kinematic profiles and the 200 m front crawl style. Nine national level male swimmers performed two speed tests: a submaximal discontinuous speed trial of progressive speed intensity, and a maximal one, simulating a 200 m front crawl style. The stroke general kinematic parameters, the phases duration of the stroke cycle, the velocity of the centre of mass and the intra cyclic variation of the horizontal velocity were herein studied. Significant kinematic differences in relation to stroke rate, horizontal velocity of the centre of mass, total cycle duration, absolute and relative duration of the propulsive sub aquatic action and the velocity of the centre of mass during the arms recovery were compared between the speed tests. Significant correlations between the performance in the maximal speed and some kinematic variables were observed.

The aim of this study was to compute and validate trunk transverse surface area (TTSA) estimation equations to be used assessing the swimmer’s drag force according to competitive level by gender. One group of 130 swimmers (54 females and 76 males) was used to compute the TTSA estimation equations and another group of 132 swimmers (56 females and 76 males) were used for its validations. Swimmers were photographed in the transverse plane from above, on land, in the upright and hydrodynamic position. The TTSA was measured from the swimmer’s photo with specific software. It was also measured the height, body mass, biacromial diameter, chest sagital diameter (CSD) and the chest perimeter (CP). With the first group of swimmers it was computed the TTSA estimation equations based on stepwise multiple regression models from the selected anthropometrical variables. The TTSA prediction equations were significant and with a prediction level qualitatively considered as moderate. All equations included only the CP and the CSD in the final models. In all prediction models there were no significant differences between assessed and estimated mean TTSA. Coefficients of determination for the linear regression models between assessed and estimated TTSA were moderate and significant. More than 80% of the plots were within the 95% interval confidence for the Bland-Altman analysis in both genders. So, TTSA estimation equations that are easy to be computed by coached and researchers were developed. All equations accomplished the validation criteria adopted.

Background: The identification of the variables that are able to predict swimming performance is one of the main purposes of the “swimming science” community. Research question: The aims of the study were: (i) to compare the anthropometric and physiological profiles of 100m and 200m front crawl swimmers and; (ii) to identify anthropometric and physiological variables that account for the prediction of the swimming performance at the 100m and 200m front crawl events. Methods: Twenty-six male swimmers were divided in two groups (12 for 100m group and 14 to 200m group). The swimmers’ personal best performance for the 100m and the 200m front crawl was converted to FINA points. The subjects performed a graded swimming test and an all-out test (100 or 200m maximal swims) in different days, in which physiological measures were evaluated. Forward step-by-step linear regression models were computed to predict swimming performance. The subjects’ performances (season best and all-out test) were taken as dependent variables. The age, physiological and anthropometric measures were selected as independent variables. Results: Anthropometric and physiological profiles of 100 and 200m swimmers are different and the mean oxygen uptake during exercise combined with training experience may explain 200m front crawl best season performance with a high precision (≈2% error). The models computed were able to predict from 44 % (i.e. 200m all-out bout) to 61 % (i.e. 200m season best) swimming performance. Predictive power of the models was less accurate in the 100m event (error > 10%). Conclusions: The authors conclude that the extent to which the physiological and anthropometric variables combine to predict performance probable is group-specific.

Quer no contexto educativo quer no contexto competitivo, grande parte do tempo das sessões de natação é despendida no ensino e aperfeiçoamento do momento de nado. No entanto, o contributo da partida e das viragens para o rendimento final também é significativo. Adicionalmente, a aplicação constante das tarefas denominadas “clássicas” tendem a originar constrangimentos que poderão afetar um saudável processo de ensino-aprendizagem. Assim, tem sido vulgar a criação de tarefas “alternativas” que facilitem a assimilação dos conteúdos propostos. Pretendeu-se com este trabalho apresentar uma seleção de exercícios “alternativos” para o ensino e aperfeiçoamento das partidas e das viragens em natação.

Online first Submitted by Tiago Manuel Barbosa (barbosa@ipb.pt) on 2012-06-29T10:27:55Z No. of bitstreams: 1 PMS-June-2012_0020.pdf: 1247210 bytes, checksum: 21f640e486a81c4236999a19673e3317 (MD5) Made available in DSpace on 2012-07-06T15:41:28Z (GMT). No. of bitstreams: 1 PMS-June-2012_0020.pdf: 1247210 bytes, checksum: 21f640e486a81c4236999a19673e3317 (MD5) Previous issue date: 2012

The aim of the study was to assess deep and shallow water teaching methods in swimming lessons for preschool children and identify variations in the basic aquatic skills acquired. The study sample included 32 swimming instructors (16 from deep water programs and 16 from shallow water programs) and 98 preschool children (50 from deep water swimming pool and 48 from shallow water swimming pool). The children were also studied regarding their previous experience in swimming (6, 12 and 18 months or practice). Chi-Square test and Fisher's exact test were used to compare the teaching methodology. A discriminant analysis was conducted with Λ wilk's method to predict under what conditions students are better or worse (aquatic competence). Results suggest that regardless of the non-significant variations found in teaching methods, the water depth can affect aquatic skill acquisition - shallow water lessons seem to impose greater water competence particularly after 6 months of practice. The discriminant function revealed a significant association between groups and all predictors for 6 months of swimming practice (p

The aim of this study was to analyze the relationships between “Sailor’s jigs” kinematics and increasing music cadence. Six young women, non-pregnant, with at least one year of experience conducting this type of head-out aquatic program, with no kind of skeletal muscle injury reported in the last six months were evaluated. The exercise was recorded on video, in the frontal plane, using a pair of cameras, enabling a double projection, from above and underwater body motions, at five increasing cadences (120 b.min-1, 135 b.min-1, 150 b.min-1, 165 b.min-1 and 180 b.min-1). Images were thereafter digitized in specific software (Ariel Performance Analysis Systems). The cycle period decreased through the incremental protocol. Cycle period decrease is done decreasing joint range of motion and increasing the limbs segmental velocity as well. Although these combined kinematical strategy, a deeper analysis reveals that subjects decrease the cycle period mainly decreasing the range of motion.

O objectivo do estudo foi desenvolver e validar equações preditivas da área de secção transversa do tronco humano, Os modelos foram desenvolvidos para o sexo masculino e de acordo com o nível competitivo, A amostra foi composta por 152 sujeitos, todos praticantes de Natação Pura desportiva, com idades entre os 10 e os 32 anos de idade. Para o desenvolvimento dos modelos foi utilizado um grupo de sujeitos para estimar a equação e um outro para validar. Foram avaliadas as seguintes características antropométricas: (i) massa corporal; (ii) estatura; (iii) diâmetro bi-acromial; (iv) diâmetro tóraco-sagital; (v) perímetro peitoral e (vi) área de secção transversal do tronco. Os modelos preditivos foram desenvolvidos através de análise de regressão linear múltipla passo-a-passo e num dos casos, com recurso ao nível competitivo enquanto variável dummy. Todos os modelos desenvolvidos incluíram como variáveis independentes o diâmetro tóraco-sagital e o perímetro peitoral (0,32 ≤ R2 ≤ 0,48; P < 0,01). No processo de validação entre as áreas de secção transversal do tronco medida e estimada, não se verificaram diferenças significativas entre valores médios (P > 0,05), as regressões lineares simples foram moderadas (0,23 ≤ R2 ≤ 0,39; 0,01 ≤ P ≤ 0,001) e o critério de Bland Altman foi em todos os casos cumprido. Pode concluir-se que os modelos desenvolvidos para nadadores masculinos, e de acordo com o nível competitivo, predizem com validade a área de secção transversa do tronco de nadadores.

Submitted by Tiago Manuel Barbosa (barbosa@ipb.pt) on 2011-06-29T15:41:26Z No. of bitstreams: 1 Biomechanics in Sports 29 - swimmer's cap.pdf: 229813 bytes, checksum: d76626cc8a086aec11d7c41424a85ede (MD5) Made available in DSpace on 2011-09-09T10:56:26Z (GMT). No. of bitstreams: 1 Biomechanics in Sports 29 - swimmer's cap.pdf: 229813 bytes, checksum: d76626cc8a086aec11d7c41424a85ede (MD5) Previous issue date: 2011

Submitted by Tiago Manuel Barbosa (barbosa@ipb.pt) on 2011-06-29T15:45:25Z No. of bitstreams: 1 Biomechanics in Sports 29 - hydrodynamics female swimmers.pdf: 79923 bytes, checksum: b481dfe85c3d196b7a11159b5d1a98ae (MD5) Made available in DSpace on 2011-07-07T09:17:47Z (GMT). No. of bitstreams: 1 Biomechanics in Sports 29 - hydrodynamics female swimmers.pdf: 79923 bytes, checksum: b481dfe85c3d196b7a11159b5d1a98ae (MD5) Previous issue date: 2011

As tarefas “clássicas” de ensino das técnicas da Natação Pura Desportiva tendem a criar uma sobrecarga sobre algumas estruturas do aparelho locomotor, monotonia nas sessões, bem como, induzir uma menor plasticidade e riqueza no domínio motriz ou do controlo motor. Daí ser vulgar propor-se aos alunos tarefas de ensino diferenciadas, “alternativas”. As técnicas de nado de Bruços e de Mariposa são tidas como das mais complexas de ensinar por manifestas dificuldades coordenativas e/ou cineantropométricas dos alunos. É objectivo deste trabalho propor um modelo taxionómico para o ensino das técnicas simultâneas de nado, apresentar uma selecção de tarefas “alternativas” para o ensino das técnicas em causa, apontando as principais vantagens e desvantagens de cada uma.

The aim of the current study was to develop a structural equation modeling (i.e., path-flow analysis model) for active drag force based on anthropometric, hydrodynamic and biomechanical variables in young swimmers. The theoretical model was developed according to main review papers about these determinants. Sixteen male swimmers (12.50±0.51 years-old; Tanner stages’ 1-2) were evaluated. It was assessed: (i) anthropometrical variables such as body mass, height, frontal surface area; (ii) hydrodynamic variables including drag coefficient and active drag with the velocity perturbation method; (iii) the biomechanical variables stroke length, stroke frequency and swimming velocity after a maximal 25-m bout. Path-flow analysis was performed with the estimation of linear regression standardized coefficients between exogenous and endogenous variables. To verify the model fit, root mean square residual was computed. The active drag presented significant association with all exogenous variables, except for stroke length and stroke frequency. Confirmatory model excluded the frontal surface area (RMSR>0.1). Even so, 95% of active drag was explained by remaining variables in the model. Confirmatory path-flow model can be considered as not suitable of the theory. In order to increase the model fit, in a near future it is advice to develop new frontal surface area estimation equations specific for young swimmers rather than using models developed with adult/elite swimmers.