Artigos de revistas
Permanent URI for this collection
Browse
Browsing Artigos de revistas by Issue Date
Now showing 1 - 10 of 63
Results Per Page
Sort Options
- A systematic review on dry-land strength and conditioning training on swimming performancePublication . Amaro, Nuno; Morouço, Pedro; Marques, M.C.; Batalha, N.; Neiva, H.; Marinho, D.A.Objectives. — The objective of this review was to examine the effects of dry-land strength and conditioning (S&C) training on swimming, and starts and turns performances. News. — S&C training is a common practice in swimming aiming to enhance performance or to prevent injuries. However, studies regarding the effects of S&C on swimming performance are scarce; the influence of age, gender or competitive level is even scarcer. Prospects and projects. — After a structured literature search, sixteen studies were included in the current review. Of those, seven did not report any positive or negative effects on swimming performance. Contrarily, most studies with positive effects were conducted with older swimmers whereas maximal strength was the most effective methodology for improving swimming performance. S&C plyometric training is suggested to be the most effective method to improve starts and turns. Future Randomized Controlled Trials should be conducted to explore the effects of S&C induced by age and gender, on different swimming distances and techniques, and long-term training effects. Conclusion. — It is recommended that S&C training should be based on maximal strength, ranging from six to twelve weeks of 2 to 4 sessions per week (approximately 24 sessions altogether). In each session, coaches should vary from 2 to 3 sets and 3 to 5 repetitions, according to prescribed intensity. Rest intervals should range between 2 to 5 minutes and the intensity should be from 80 to 90% of 1RM. Particularly regarding improving starts and turns, a S&C training regime ranging from 6 to 8 weeks and with 2 sessions per week is suggested. In each session, swimmers should perform between 1 and 6 sets and 1 and 10 repetitions, according to the established intensity. Rest between sets should range from 60 to 90 seconds. The swimmers in the included studies are mostly men which do not allow to say if the recommendations made are gender-dependent.
- Sport injuries in Portuguese female and male karateka: a retrospective studyPublication . VencesBrito, António M.; Rodrigues-Ferreira, Mário; Castro, Maria Antonio; Polak, Ewa; Valente, Eduardo Jorge; Romero, Felix; Figueiredo, AbelBackground. Karate is a combat sport in which, as in all sports, there are risk factors that lead to injuries to its practitioners. Problem and Aim. Little is known about injuries in Portuguese karateka. Thus, the purpose of this study was to investigate the type and incidence of injury in both female and male Portuguese karate practitioners. Material and Methods. The sample was composed of 490 karate practitioners from nine different karate styles, 105 females and 385 males. In this retrospective study a questionnaire of morbidity was applied, in which participants recorded their demographic data and injury episodes occurring in the last three sports seasons. Results. Of the full sample, 51.8% (n=254) reported one or more injuries. No statistical differences were found between the sexes. Most frequent injuries were fractures (16.1%) and trauma (15.6%) in both sexes and occurred in the lower limb (64.3% in females and 52.0% in males). The mechanism responsible for most of injuries in females were falls (12.5%), while in males it was punch actions (10.3%). Injuries were reported as moderate to severe, causing inactivity of practice of between 8 and 21 days and higher, respectively. Most injuries occurred in the preparatory period (63.6% females, males 53.2%), and mainly occurred in training (85.5% in females and 84.5% in males). Conclusions. Coaches should analyse the specificity of the gender training process to prevent the appearance of injuries, and increase the use of preventive processes, such as the use of protection or practice in place, and with safe equipment.
- A Brief Review on Processes for Cartilage RepairPublication . Moura, Carla; Santos-Rocha, RA; Franco, Susana; Malça, Cândida; Galhano, Cristina; Henriques, Marta; Morouço, PedroThe aim of the present review was to highlight some of the available processes for cartilage repair and regeneration. Considering the high impact that cartilage degeneration has in the quality of life, in an aging society, efforts to promote better treatments are crucial. The current available processes have advantages and drawbacks, that should be further investigated, aiming to obtain tailored and successful repair. Finally, some suggestions for tissue engineering strategies are presented, so that the scientific community can debate pros and cons to be investigated.
- Fadiga e qualidade de vida em bailarinos profissionais de dança de salão no BrasilPublication . Cardoso, Allana; Martins Reis, Nycolle; Da Silva, Jaqueline; Borgatto, Adriano; Folle, Alexandra; Resende, Rui; Coutinho De Azevedo Guimarães, AdrianaObjetivou-se analisar a relação entre a qualidade de vida, a fadiga e as lesões em bailarinos brasileiros profissionais de dança de salão. Participaram 320 profissionais das cinco regiões do Brasil, sendo a coleta de dados realizada por meio de um questionário online autoaplicável acerca das informações gerais, WHOQOL-bref, Questionário de Fadiga de Yoshitake e Questionário de Identificação de Lesões em Bailarinos. Para análise dos dados utilizou-se a estatística descritiva, seguida da análise inferencial e do teste de Regressão Linear Múltipla. Os resultados demonstram que uma maior fadiga está associada a uma qualidade de vida negativa, evidenciando-se que, a cada valor a mais na fadiga total, espera-se que a qualidade de vida diminuísse 0.218 pontos no domínio físico; 0.226 pontos no domínio psicológico; 0.420 pontos no domínio social; e 0.304 pontos no domínio ambiental. Em contrapartida, a incidência e a intensidade de lesões não foram associadas com a qualidade de vida. Conclui-se que o contexto da dança de salão profissional pode influenciar tanto na presença de fadiga quanto na qualidade de vida. Sugere-se aos profissionais de saúde que atuam com estes bailarinos através de intervenções multifatoriais objetivando diminuir a fadiga, atenuando os efeitos desta na qualidade de vida
- Perceptions of Parenting Practices and Psychological Variables of Elite and Sub-Elite Youth AthletesPublication . Teques, Pedro; Calmeiro, Luis; Rosado, António; Silva, Carlos Manuel Marques; Serpa, SidónioDrawing from the model of parental involvement in sport, the overall purpose was to examine the associations of perceptions of parenting practices (encouragement, reinforcement, instruction, and role modeling) and athletes’ psychological variables (self-efficacy, social self-efficacy, self-regulation, and intrinsic motivation) of elite and sub-elite youth athletes. Participants were elite (n = 210) and sub-elite (n = 635) athletes aged between 14 and 18 years (Mage = 16.58, SD = 1.33). Structural equation modeling analysis revealed that young elite athletes’ perceptions of sport-related parenting practices are associated with their psychological skills and performance level in sport. Specifically, in comparison with their sub-elite peers, perceptions of parental encouragement had a significantly different strong effect on intrinsic motivation. Moreover, perceptions of parental modeling revealed different effects on performance level, as well as on intrinsic motivation, and self-regulation. These perceptions of parenting practices may promote a positive learning environment, resulting in an increased likelihood of achieving a high level of sport performance in comparison with their sub-elite peers.
- How best to quantify home advantage in team sports: an investigation involving male senior handball leagues in Portugal and Spain. [La mejor manera de cuantificar la ventaja de jugar en casa en deportes de equipo: una investigación con ligas de Balonmano senior masculino en Portugal y España]Publication . Matos, Rui; Amaro, Nuno; Pollard, RichardHome advantage (HA), or the effect of match location, has been shown to play an important role in determining the result of a game. A method introduced over 30 years ago has enjoyed wide use. However, there is a possible problem with its interpretation. Although this can be overcome by rescaling the original value for HA, this paper introduces a somewhat different approach to quantifying HA, one that is derived by expressing home performance specifically as a function of away performance. The various methods are illustrated by analyzing HA for teams in the men’s professional handball leagues in Portugal and Spain for the 2016-17 season. Results show that the traditional and rescaled methods both ensure a maximum value of 100% for HA, while the new method can produce values well above 100%. Also, when HA is small, as in the case of goals scored and conceded, then values from the new method are about twice those from the rescaled method. However, when HA is larger, as in the case of most of the teams in the lower half of the Spanish league table, when based on points, the new method produces HA values which are much higher that the rescaled. This method provides a new dimension to consider when trying to quantify HA. It has the advantage of also being appropriate for the difference between goals scored and goals conceded. Choice of methodology will depend on the specific objective being sought when studying the effect of HA on performance
- Ensinar o treinador a ser um treinador de futebol: Uma abordagem teórica com implicações práticas.Publication . Rodrigues, Filipe; Rita, Rita; Cid, Luis; Teixeira, Diogo; Monteiro, DiogoThis study aimed at analyzing the effect of the motivational climate induced by coaches in young athletes’ effort perception, through a hybrid model, developed based on the Achievement Goal Theory and the SelfDetermination Theory. Data from 803 male athletes aged between 14 and 20 years (M=17.60; SD=2.21), with a weekly training frequency between 2 to 6 times a week (M=3.56; SD=.85) and workout duration between 60 to 300 minutes (M=99.75; SD=21.08) was analyzed. Participants completed four questionnaires previously translated and validated for Portuguese in the context of sport. Goodness-of-fit indexes of the measurement model and the structural model showed acceptable fit. All regressions proved to be significant, taking into account theoretical assumptions. The indirect effects show that the task-oriented climate positively predicts the perceived effort, both through autonomous motivation and through controlled motivation. Conversely, ego-oriented climates had a negative and significant indirect effect on perceived effort, regardless of the motivational regulation. In practical terms, young athletes’ coaches should focus on the learning process and on developing new skills among the athletes, value progress and effort, individually and as a team, and creating a balanced and harmonious engagement between athletes.
- A Rapidly Incremented Tethered-Swimming Maximal Protocol for Cardiorespiratory Assessment of SwimmersPublication . Pessôa Filho, Dalton M.; Massini, Danilo A.; Siqueira, Leandro O. C.; Santos, Luiz Gustavo A.; Vasconcelos, Camila M. T.; Almeida, Tiago A. F.; Espada, Mário; Reis, Joana F.; Alves, Francisco B.; DiMenna, Fred J.Incremental exercise testing is the standard means of assessing cardiorespiratory capacity of endurance athletes. While the maximal rate of oxygen consumption is typically used as the criterion measurement in this regard, two metabolic breakpoints that reflect changes in the dynamics of lactate production/consumption as the work rate is increased are perhaps more relevant for endurance athletes from a functional standpoint. Exercise economy, which represents the rate of oxygen consumption relative to performance of submaximal work, is also an important parameter to measure for endurance-athlete assessment. Ramp incremental tests comprising a gradual but rapid increase in work rate until the limit of exercise tolerance is reached are useful for determining these parameters. This type of test is typically performed on a cycle ergometer or treadmill because there is a need for precision with respect to work-rate incrementation. However, athletes should be tested while performing the mode of exercise required for their sport. Consequently, swimmers are typically assessed during free-swimming incremental tests where such precision is difficult to achieve. We have recently suggested that stationary swimming against a load that is progressively increased (incremental tethered swimming) can serve as a "swim ergometer" by allowing sufficient precision to accommodate a gradual but rapid loading pattern that reveals the aforementioned metabolic breakpoints and exercise economy. However, the degree to which the peak rate of oxygen consumption achieved during such a protocol approximates the maximal rate that is measured during free swimming remains to be determined. In the present article, we explain how this rapidly incremented tethered-swimming protocol can be employed to assess the cardiorespiratory capacity of a swimmer. Specifically, we explain how assessment of a short-distance competitive swimmer using this protocol revealed that his rate of oxygen uptake was 30.3 and 34.8 mL∙min 1∙kg-1BM at his gas-exchange threshold and respiratory compensation point, respectively.
- How To Prepare a Technical Coordination in Youth Development Soccer AcademyPublication . Teixeira, Eduardo; Loureiro, Nuno; Costa, João PauloIt’s consensual that the sports training provided by clubs must respond to a demanding process of preparation, development and consolidation of a methodological and pedagogical scope. So, we expose the concerns inherent to one of the four dimensions of a Technical Coordination(TC) modulation work in a football training entity, specifically at the level of its conceptualization.
- V̇O2 kinetics and energy contribution in simulated maximal performance during short and middle distance-trials in swimmingPublication . Almeida, Nalvo F; Pessôa Filho, Dalton; Espada, Mário; Reis, Joana F.; Simionato, Astor R.; Siqueira, Leandro O. C.; Alves, Francisco B.Purpose: This study aims to analyze swimmers' oxygen uptake kinetics ([Formula: see text]K) and bioenergetic profiles in 50, 100, and 200 m simulated swimming events and determine which physiological variables relate with performance. Methods: Twenty-eight well-trained swimmers completed an incremental test for maximal oxygen uptake (Peak-[Formula: see text]) and maximal aerobic velocity (MAV) assessment. Maximal trials (MT) of 50, 100, and 200-m in front crawl swimming were performed for [Formula: see text]K and bioenergetic profile. [Formula: see text]K parameters were calculated through monoexponential modeling and by a new growth rate method. The recovery phase was used along with the blood lactate concentration for bioenergetics profiling. Results: Peak-[Formula: see text] (57.47 ± 5.7 ml kg-1 min-1 for male and 53.53 ± 4.21 ml kg-1 min-1 for female) did not differ from [Formula: see text]peak attained at the 200-MT for female and at the 100 and 200-MT for male. From the 50-MT to 100-MT and to the 200-MT the [Formula: see text]K presented slower time constants (8.6 ± 2.3 s, 11.5 ± 2.4 s and 16.7 ± 5.5 s, respectively), the aerobic contribution increased (~ 34%, 54% and 71%, respectively) and the anaerobic decreased (~ 66%, 46% and 29%, respectively), presenting a cross-over in the 100-MT. Both energy systems, MAV, Peak-[Formula: see text], and [Formula: see text] peak of the MT's were correlated with swimming performance. Discussion: The aerobic energy contribution is an important factor for performance in 50, 100, and 200-m, regardless of the time taken to adjust the absolute oxidative response, when considering the effect on a mixed-group regarding sex. [Formula: see text]K speeding could be explained by a faster initial pacing strategy used in the shorter distances, that contributed for a more rapid increase of the oxidative contribution to the energy turnover