The execution distance is a tactic factor that affects mechanical performance and execution technique in taekwondo. This study analyzes the roundhouse kick to the head by comparing the maximum impact force, execution time, and impact time in 3 distances according to the athletes' competition level. It also analyzes the relationship between impact force and weight in each group. It examines whether the execution distance affects the maximum impact force, execution time, and impact time, in each level group or 2 different competition levels. Participants were 27 male taekwondo players (13 medallists and 14 nonmedallists). The medallists executed the roundhouse kick to the head with greater impact force and in a shorter execution time than did the nonmedallists when they kicked from any distance different to their combat distance. However, the results showed that the execution distance is influential in the execution time and impact time in the nonmedallist group. It is considered appropriate to orientate the high-level competitors to train for offensive actions from any distance similar to the long execution distance because it offers equally effectiveness and a greater security against the opponent. Also, practitioners should focus their training to improve time performance because it is more affected by distance than impact force.

In the context of education, this study examined the relationship between perceiving a transformational physical education (PE) teacher and student’s leisure-time physical activity (PA). Furthermore, we tested the potential mediation role of motivational learning climate, passion and self-determined motivation in this relationship. The sample was composed of 2210 high-school PE students (1145 males, 1065 females) between 16 and 20 years of age. Results of structural equation modeling revealed that the perceived transformational PE teacher–PA outcomes relationship was stronger when students perceived a task-involving climate, when they were harmoniously passionate, and when they were self-determined. We conclude that students’ health-enhancing behaviours could be improved if their PE teachers use transformational teaching style and created a task-oriented learning climate.

The aim of this study was to investigate the effects of target distance on temporal and impact force parameters that are important performance factors in taekwondo kicks. Forty-nine taekwondo athletes (age = 24.5 ± 5.9 years; mass = 79.9 ± 10.8 kg) were recruited: 13 male experts, 21 male novices, 8 female experts, and 6 female novices. Impact force, reaction time, and execution time were computed. Three-way repeated measure ANOVAs revealed significant ‘distance’ effect on impact force, reaction time, and execution time (p = 0.001). Comparisons between distance conditions revealed that taekwondo athletes kicked with higher impact force from short distance (17.6 ± 7.5 N/kg) than from long distance (13.1 ± 5.7 N/kg) (p < 0.001), had lower reaction time from short distance (498 ± 90 ms) and normal distance (521 ± 111 ms) than from long distance (602 ± 121 ms) (p < 0.001), and had lower execution time from short distance (261 ± 69 ms/m) than from normal distance (306 ± 105 ms/m) or from long distance (350 ± 106 ms/m) (p = 0.003 and p < 0.001, respectively). In conclusion, target distance affected the kick performance; as distance increases, impact force decreased and reaction time increased. Therefore, when reaction to a simple visual stimulus is needed, kicking from a long distance is not recommended, as longer time is required to respond.

ResumenObjetivoExaminar la fiabilidad y la validez de una escala para evaluar las barreras percibidas en el desplazamiento activo al centro escolar en jóvenes españoles.MétodoLa validez de la escala fue evaluada en una muestra de 465 adolescentes (14-18 años de edad) mediante un análisis factorial confirmatorio y a través de la asociación con el transporte activo autorreportado. Una submuestra completó la escala dos veces, con una separación de una semana, a fin de evaluar su fiabilidad.ResultadosLos resultados mostraron que la escala tenía índices de ajuste satisfactorios con dos factores. Un factor incluyó los ítems relativos a ambiente y seguridad (α=0,72), y otro los ítems sobre planificación y aspectos psicosociales (α=0,64). El transporte activo se relacionó significativamente con la puntuación total de la escala de barreras (rho=−0,27; p <0,001), con las barreras ambientales/seguridad (rho=−0,22; p <0,001) y con las barreras de planificación/psicosociales (rho=−0,29; p <0,001). Los test-retest (coeficiente de correlación intraclase) para las barreras mostraron valores entre 0,68 y 0,77.ConclusiónLa escala muestra una validez aceptable y una fiabilidad adecuada para evaluar las barreras en el transporte activo al centro educativo en jóvenes españoles.AbstractObjectiveTo examine the reliability and validity of a scale to measure perceived barriers to active commuting to school among Spanish young people.MethodThe validity of the scale was assessed in a sample of 465 adolescents (14–18 years) using a confirmatory factor analysis and studying its association with self-reported active commuting to school. The reliability of the instrument was evaluated in a sub-sample that completed the scale twice separated by a one-week interval.ResultsThe results showed that the barriers scale had satisfactory fit indices, and two factors were determined. The first included environment- and safety-related items (α=0.72), while the other concerned planning and psychosocial items (α=0.64). Active commuting to school showed significant correlations with the total score of the barriers scale (rho=−0.27; p <0.001), with the environmental/safety barriers (rho=−0.22; p <0.001), as well as with the planning/psychosocial barriers (rho=−0.29; p <0.001). Test-retest ICCs for the barriers ranged from 0.68 to 0.77.ConclusionThe developed scale has acceptable validity and good reliability to assess barriers to active commuting to school among Spanish young people