Sprints with changes of direction (COD) have been traditionally associated with performance in team sports. Jumping tests have been used as predictors of COD; however, there are not too many studies analyzing how dominance affects the best performance of the turn. The purpose of this study was to explore the relationship between tests pertaining to jumps (1 and 2 legs) and COD (right and left turns). Forty-two male students were selected at the Faculty of Physical Education (age: 20.1 ± 3.7 years; weight: 73.4 ± 8.4 kg; body mass index: 23.1 ± 2.6 kg·m(-2); and fat mass: 17.1 ± 8.8%). All the subjects had right leg dominance. The COD tests were assessed using three 10-m sprint tests (90° right and left turns and 180° turn). Jumps were countermovement jumps (CMJs with 1 and 2 legs) and the drop jump (DJ). Pearson coefficient correlation and stepwise regression analyses were performed. Our results showed that both CMJs and DJs were associated with COD. The CMJ with the right leg had the best coefficient correlation with left COD time (r = -0.64; p < 0.01). Also, the CMJ was associated with COD180° time (r = -0.60; p < 0.01). After regression analysis, only right one-leg CMJ and CMJ were predictors of left COD time (adjusted R2 = 0.46; p < 0.01). The main finding of this study was that the CMJ, but not the DJ, was the best predictor of dominant side COD. Jumps are an important component of team sport training because they improve COD performance. However, coaches use several types of jumps during training; our results suggest that jumps similar to the CMJ should be useful tools to improve COD, which helps to specify better training prescription.

Soccer players undergo an evolution in their body composition throughout the growth and passage through the different base stages, that is, childhood, puberty and adolescence. The aim of this study was to analyze the morphology and body composition of U14, U16, and U19 soccer players, taking into account in addition, their sport success endorsed through the regularity participation and their relation with the different playing positions occupied during competition (goalkeeper, external defender, central defender, midfielder and forward/extreme). For that, a total of 174 male young soccer players were evaluated anthropometrically. Dominant somatotype of the players was, according to their playing position: meso-endomorphic in goalkeepers, central for external defenders, balanced ectomorph in central defenders, balanced mesomorph in the case of midfielders, and meso-ectomorph in forwards/extremes. Taking into account that sport performance is directly mediated by the body composition of athletes, the differences found suggest a marked specialization between the goalkeepers and forwards, establishing significant differences between them. Further studies would be needed to evaluate the influence of individual maturation development versus sports training on the conformation of a certain anthropometric profile of a soccer player and its relation with the different playing positions occupied on the pitch during the game.

The period of adolescence stands out as a critical and decisive phase, first because it leaves its mark on personality development, which is affected by psychosocial factors, and second because the healthy lifestyle habits acquired during this stage form a foundation for adulthood. The objective of the present study was first to evaluate the levels of participation in physical activities (PA) and of self-concept in high school and university students, and second to find relationships between these psycho-physical variables. Four hundred and forty adolescents ranging in age from 16 to 20 years, from Spain and Portugal, participated in this study (cross-sectional design). The IPAQ and Self-Concept Form-5 questionnaires were used. The results demonstrated some differences; the Portuguese university students had lower scores in the academic, emotional and physical dimensions and vigorous PA but higher sitting time, walking and moderate PA compared to Portuguese high school students. In addition, Spanish university students had lower self-concept scores although higher practice of PA and lower sitting time than Spanish high school students ( p < 0.05). On the other hand, a positive relationship was found between different dimensions of self-concept and levels of PA, while the relationship between these dimensions and the time the adolescent spent sitting was negative. In conclusion, the university students have lower scores of self-concept dimensions (in general), and the practice of PA is higher in Spanish university students, confirming the clear presence of differences between both educational stages. The relationship between the dimensions of self-concept in general and the level of PA was positive (following the contributions of Marsh).

The aim of this study was to analyze the level of satisfaction in three municipal sports centers in the city of Malaga and to learn and analyze the characteristics of users older than 40 years of age in these centers. A total of 303 persons (123 men and 180 women) from three sports centers in the city of Malaga participated in this study (M = 58.14, SD = 7.16 years). The Evaluation of Perceived Quality in Sports Services test (CECASDEP) was used, and the results demonstrated that the different dimensions studied—sports center, activity space, locker rooms, program of activities, and trainer—were very positively correlated. The level of customer loyalty increased with user satisfaction and perceived quality of services as well as the age of the person. Users were also found to be more motivated to take part in physical activities due to greater satisfaction. The highest scores were given to the trainers, who played a key role in all three sports centers. In conclusion, we gathered important insights into perceived quality in different sports centers. This information can be used by sports managers to strengthen dimensions with lower scores and improve those with higher scores. In addition, the study confirms that the level of customer loyalty is related to the perceived quality scores. Therefore, the use of measuring instruments is recommended to optimize the quality of sports services.

Physical activity (PA) can bring incalculable benefits to people throughout the aging process. The objective of this study was to determine the relationships between the leg and arm strength, body composition and balance of elderly people. Twenty-one people (9 men and 12 women) over 60 years of age voluntarily participated in this study. Bioimpedance tests were carried out to obtain body mass data, manual dynamometer tests and the lower limbs test were conducted to obtain strength values, and the stork balance stand test was conducted to assess static balance. As a result, medium-high correlation coefficients were obtained between the aforementioned dependent variables. The highest value corresponded to the relationship between the results of the dominant hand strength test (right hand in all participants) and the lean body mass (LBM) of the participant (R 2 = 75%, p < 0.001). The results indicated that strength capacity, recorded by dynamometry, and balance ability have a direct relationship with the body composition of the subject, especially with their lean body mass. These data suggest that a greater lean body mass can provide greater strength and balance in the elderly, so it would improve or have greater duration the functionality and independence of the person, thereby justifying direct benefits in people and indirect benefits in public administrations that finance these social issues.