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- The effectiveness of pilates training interventions on older adults’ balance: a systematic review and meta-analysis of randomized controlled trialsPublication . Sampaio, Tatiana; Encarnação, Samuel; Santos, Olga Maria; Narciso, Diogo; Oliveira, João P.; Teixeira, José Eduardo; Forte, Pedro; Morais, J.E.; Vasques, Catarina; Monteiro, A.M.Pilates training intervention programs have gained attention as a potential approach to enhancing balance in older adults, thereby reducing the risk of falls. In light of these considerations, this systematic review and meta-analysis aimed to critically evaluate the existing evidence and determine the effect of Pilates training intervention programs on older adults’ balance. Materials and Methods: The literature was searched through the PubMed, Web of Science, and Scopus databases from inception until July 2023. The primary keywords used for the literature search included “elderly” or “older adults” and “pilates training” and “balance”. Results: The systematic review through qualitative analysis showed robust evidence about the efficacy of Pilates intervention programs in improving older adults’ balance. The pooled meta-analysis of static and dynamic balance showed that eight (53%) out of a total fifteen analyzed interventions presented a significant effect of Pilates in improving the participants’ balance, without between-study heterogeneity. In addition, the meta-analysis regarding dynamic balance showed that six (67%) out of nine analyzed interventions presented a significant effect of Pilates in improving the participants’ balance, without heterogeneity between studies. Similarly, the meta-analysis regarding static balance showed that four (50%) out of eight analyzed studies presented significant effects on the older adults’ balance, where moderate between-study heterogeneity was found. Sensitivity analysis showed that three studies reduced the between-study heterogeneity (19, 17.6, and 17%), regressing from moderate to low heterogeneity, p < 0.05. Conclusions: This systematic review and meta-analysis underscores the potential of Pilates training as a valuable intervention to enhance balance in the elderly population
- Editorial: Coaches' role in youth sports performance: early specialization versus long-term developmentPublication . Morais, J.E.; Marinho, D.A.; Castro, Flávio A. de Souza; Barbosa, Tiago M.Youth sports are planned sports programs for children and adolescents with designated coaches, organized practices, and scheduled competitions. Such programs can be organized and implemented at schools (by physical education teachers instead of coaches), as well as in other sports organizations (i.e., federations, associations, local clubs). Primary aim should be to focus on providing young athletes with fundamental motor skills in tandem to their maturation stage. Indeed, these programs are aimed at mass participation rather than on developing elite athletes. The participation in such programs during childhood and adolescence showed to have major benefits in children’s and adolescent’s physical, psychological, and social development. On the other hand, youth sports programs can also serve as a link to talent identification and development programs aiming to identify young athletes with potential for success in adult/elite sport. As they aremass orientated,many youth athletes can be observed which will increase the likelihood of talent identification. Afterwards, these athletes can be guided to high-performance programs aiming to achieve eventually an elite level.
- Efeitos de um programa de 12 semanas de Hidroginástica na postura corporal de mulheres de meia-idadePublication . Matias, Paula; Morais, J.E.; Costa, M.J.; Barbosa, Tiago M.À medida que a população mundial envelhece, sérias preocupações são levantadas sobre o efeito do exercício físico e de aptidão física para a saúde pública, especialmente na meia e terceira idade (Cruz-Ferreira et al., 2011). Os programas de exercícios aquáticos ganharam popularidade devido à diminuição de hipotéticos pacientes (i.e. ajudam na prevenção de patologias), e até mesmo entre indivíduos saudáveis (Costa et al., 2011). Ambos os programas, terrestres e aquáticos, baseiam-se no objetivo de alcançar e manter um nível adequado de aptidão física (incluindo a postura corporal) e, portanto, melhorar a qualidade de vida. A postura corporal tem em consideração a oscilação e/ou o alinhamento do corpo. O alinhamento do corpo representa a posição do corpo e a relação espacial entre os seus segmentos anatómicos para manter o equilíbrio, em condições estáticas ou dinâmicas, de acordo com os requisitos do ambiente e da tarefa motora. Um alinhamento adequado do corpo envolve o menor esforço (i.e. gasto energético) e sobrecarga mecânica, para otimizar a eficiência do sistema biológico. Uma postura corporal incorreta pode estar relacionada com alguma desordem a nível ortopédico (Kristensen, Bandholm, Holm, Ekdahl, & Kehlet, 2009), músculo-esquelético (Oyarzo, Villagrán, Silvestre, Carpintero, & Berral, 2013) ou neurológico (Busse, Zimdars, Zalewski, & Steffen, 2005), mas também associada com uma maior probabilidade de quedas (Sakamoto et al., 2006).
- Longitudinal modeling in sports: young swimmers' performance and biomechanics profilePublication . Morais, J.E.; Marques, Mário C.; Marinho, D.A.; Silva, A.J.; Barbosa, Tiago M.The aims was to model a latent growth curve of young swimmers' performance over a season and its relationship with biomechanics, quantify the direct effect of the exogenous variables selected on performance across a season and analyze the sex effect on the performance growth. Fourteen boys (12.33±0.65 years) and 16 girls (11.15±0.55 years) were evaluated. Performance, stroke frequency, speed fluctuation, arm's propelling efficiency, active drag, active drag coefficient and power to overcome drag were collected in four different moments of the season. Latent growth curve modeling was computed to understand the longitudinal variation of performance (endogenous variables) over the season according to the biomechanics (exogenous variables). Latent growth curve modeling showed a high inter- and intra-subject variability in the performance growth. Sex had a significant effect at the baseline and during the performance growth. In each evaluation moment, different variables had a meaningful effect on performance (M1: Da, β=-0.62; M2: Da, β=-0.53; M3: ηp, β=0.59; M4: SF, β=-0.57; all P<0.001). The models' good-of-fit was 1.40≤x2/df≤3.74 (good-reasonable). Latent modeling is a comprehensive way to gather insight about young swimmers' performance over time. Different variables were the main responsible for the performance improvement. A gender gap, intra- and inter-subject variability was verified.
- Modelling the relationship between biomechanics and performance of young sprinting swimmersPublication . Morais, J.E.; Silva, A.J.; Marinho, D.A.; Marques, Mário C.; Batalha, Nuno; Barbosa, Tiago M.The aim of this study was to compute a swimming performance confirmatory model based on biomechanical parameters. The sample included 100 young swimmers (overall: 12.3 ± 0.74 years; 49 boys: 12.5 ± 0.76 years; 51 girls: 12.2 ± 0.71 years; both genders in Tanner stages 1-2 by self-report) participating on a regular basis in regional and national-level events. The 100 m freestyle event was chosen as the performance indicator. Anthropometric (arm span), strength (throwing velocity), power output (power to overcome drag), kinematic (swimming velocity) and efficiency (propelling efficiency) parameters were measured and included in the model. The path-flow analysis procedure was used to design and compute the model. The anthropometric parameter (arm span) was excluded in the final model, increasing its goodness-of-fit. The final model included the throw velocity, power output, swimming velocity and propelling efficiency. All links were significant between the parameters included, but the throw velocity-power output. The final model was explained by 69% presenting a reasonable adjustment (model's goodness-of-fit; x(2)/df = 3.89). This model shows that strength and power output parameters do play a mediator and meaningful role in the young swimmers' performance.
- Young swimmers’ classification based on performance and biomechanical determinants: determining similarities through cluster analysisPublication . Morais, J.E.; Barbosa, Tiago M.; Neiva, Henrique P.; Marques, Mário C.; Marinho, D.A.The aim of this article has been to classify swimmers based on kinematics, hydrodynamics, and anthropometrics. Sixty-seven young swimmers made a maximal 25 m front-crawl to measure with a speedometer the swimming velocity (v), speed-fluctuation (dv) and dv normalized to v (dv/v). Another two 25 m bouts with and without carrying a perturbation device were made to estimate active drag coefficient (CDa). Trunk transverse surface area (S) was measured with photogrammetric technique on land and in the hydrodynamic position. Cluster 1 was related to swimmers with a high speed fluctuation (ie, dv and dv/v), cluster 2 with anthropometrics (ie, S) and cluster 3 with a high hydrodynamic profile (ie, CDa). The variable that seems to discriminate better the clusters was the dv/v (F = 53.680; P < .001), followed by the dv (F = 28.506; P < .001), CDa (F = 21.025; P < .001), S (F = 6.297; P < .01) and v (F = 5.375; P = .01). Stepwise discriminant analysis extracted 2 functions: Function 1 was mainly defined by dv/v and S (74.3% of variance), whereas function 2 was mainly defined by C Da (25.7% of variance). It can be concluded that kinematics, hydrodynamics and anthropometrics are determinant domains in which to classify and characterize young swimmers' profiles
- The effect of ball compression and scale court sizes on learning tennis skills of beginner adult tennis playersPublication . Kilit, Bulent; Arslan, Ersan; Soylu, Yusuf; Morais, J.E.Numerous studies have demonstrated the positive impact of scaled equipment on the playing performance of young tennis players. Nonetheless, there is a need for further research to explore the impact of scaled equipment on the skill development of beginner adult tennis players. Objective: This study aimed to assess the effects of ball compression and scale court sizes on the learning of tennis skills of beginner adult tennis players. Methods: Twenty-four beginner players (age 20.9 ± 1.2 years) were randomly divided into a regular ball group (RB, n = 12) and a low-compression ball group (LCB, n = 12) on-court training twice per week for six weeks. The RB played with standard yellow tennis balls, while the LCB used low-compression balls (red, orange, and green) during the intervention. Pre and post-tests included the Tennis-Specific Skills Tes (TSST) and the International Tennis Number test (ITN). Results: The results demonstrated that the LCB showed higher technical characteristics after training (p < .05, ηp 2 between .18 and .36) except for the mobility assessment (p > .05, ηp 2 = .02) and the TSST scores in terms of forehand, backhand, and rally length (p < .05, ηp 2 = .16–.19). Conclusions: This study indicates that the LCB might be more suitable equipment to improve technical skills and hitting performances. Practitioners can use the LCB to design an effective training plan, especially for young and adult beginner tennis players.
- Estimation of an elite road cyclist resistive forces and performance wearing standard and aero helmets: an analytical procedure and numerical simulations approachPublication . Forte, Pedro; Marinho, D.A.; Barbosa, Tiago M.; Morais, J.E.The aim of this study was to assess and compare by numerical simulations and analytical models the resistive forces, mechanical power, energy cost and velocity using two different types of road helmets (standard vs aero road helmet). An elite cyclist was scanned on the racing bicycle, wearing his competition gear and helmets. Numerical simulations by Computational Fluid Dynamics were carried-out at 11.11 m/s (40 km/h) and 20.83 m/s (75 km/h) to extract the drag force. The mechanical power and energy cost were estimated by analytical procedures. The drag forces were between 9.93 N and 66.96 N across the selected speeds and helmets. The power to overcome drag were 182.19 W and 1121.40 W. The total power lower and higher values were 271.05 W and 1558.02 W. The energy cost estimation was between 106.89 J/m and 381.40 J/m across the different speeds and helmets. The standard helmet imposed higher drag and demanded more power.
- Estimation of an elite road cyclist performance in different positions based on numerical simulations and analytical proceduresPublication . Forte, Pedro; Marinho, D.A.; Barbosa, Tiago M.; Morouço, Pedro; Morais, J.E.The aim of this study was to use numerical simulations and analytical procedures to compare a cyclist's performance in three different cycling positions. An elite level road cyclist competing at a national level was recruited for this research. The bicycle was 7 kg and the cyclist 55 kg. A 3D scan was taken of the subject on the competition bicycle, wearing race gear and helmet in the upright position, in the handlebar drops (dropped position) and leaning on the elbows (elbows position). Numerical simulations by computer fluid dynamics in Fluent CFD code assessed the coefficient of drag at 11.11 m/s. Following that, a set of assumptions were employed to assess cycling performance from 1 to 22 m/s. Drag values ranged between 0.16 and 99.51 N across the different speeds and positions. The cyclist mechanical power in the elbows position differed from the upright position between 0 and 23% and from the dropped position from 0 to 21%. The cyclist's energy cost in the upright position differed 2 to 16% in comparison to the elbows position and the elbows position had less 2 to 14% energy cost in comparison to the dropped position. The estimated time of arrival was computed for a 220,000 m distance and it varied between 7,715.03 s (2 h:8 min:24 s) and 220,000 s (61 h:6 min:40 s) across the different speeds and positions. In the elbows position, is expected that a cyclist may improve the winning time up to 23% in comparison to he upright and dropped position across the studied speeds
- Analysis of a normal and aero helmet on an elite cyclist in the dropped positionPublication . Forte, Pedro; Marinho, D.A.; Barbosa, Tiago M.; Morais, J.E.Cyclists use to wear different helmets and adopt different body positions on the bicycle to minimize resistance. The aim of this study was to compare a standard helmet with the new aero road helmets in a bicycle-cyclist system by CFD on the dropped position. An elite level road cyclist volunteered to this research. The cyclist was scanned on his racing bicycle on the dropped position wearing competition gear and a standard helmet and an aero road helmet. A three-dimensional domain around the cyclist with 7 m of length, 2.5 m of width and 2.5 m of height and meshed with more than 43 million of prismatic and tetrahedral elements. The numerical simulations were conducted at 11.11 m/s. The numerical simulations outputs were viscous, pressure and total drag and coefficient of drag. The standard helmet presented a viscous drag of 10.52 N, a pressure drag of 16.51 N and a total drag of 21.98 N. The aero road helmet presented a pressure drag of 7.40 N, a viscous drag of 12.56 N and a total drag of 19.96 N. Moreover, the aero road helmet presented a lower viscous, pressure and total drag coefficient in comparison to the standard helmet. It is possible to conclude that an aero road helmet imposes less drag in comparison to a standard helmet.