Jump-Rope Training: Improved 3-km Time-Trial Performance in Endurance Runners via Enhanced Lower-Limb Reactivity and Foot-Arch Stiffness.

CONTEXT: Plyometric training promotes a highly effective neuromuscular stimulus to improve running performance. Jumping rope (JR) involves mainly foot muscles and joints, due to the quick rebounds, and it might be considered a type of plyometric training for improving power and stiffness, some of the key factors for endurance-running performance. PURPOSE: To determine the effectiveness of JR during the warm-up routine of amateur endurance runners on jumping performance, reactivity, arch stiffness, and 3-km time-trial performance. METHODS: Athletes were randomly assigned to an experimental (n = 51) or control (n = 45) group. Those from the control group were asked to maintain their training routines, while athletes from the experimental group had to modify their warm-up routines, including JR (2-4 sessions/wk, with a total time of 10-20 min/wk) for 10 weeks. Physical tests were performed before (pretest) and after (posttest) the intervention period and included jumping performance (countermovement-jump, squat-jump, and drop-jump tests), foot-arch stiffness, and 3-km time-trial performance. Reactive strength index (RSI) was calculated from a 30-cm drop jump. RESULTS: The 2 × 2 analysis of variance showed significant pre-post differences in all dependent variables (P < .001) for the experimental group. No significant changes were reported in the control group (all P ≥ .05). Pearson correlation analysis revealed a significant relationship between Δ3-km time trial and ΔRSI (r = -.481; P < .001) and ΔStiffness (r = -.336; P < .01). The linear-regression analysis showed that Δ3-km time trial was associated with ΔRSI and ΔStiffness (R2 = .394; P < .001). CONCLUSIONS: Compared with a control warm-up routine prior to endurance-running training, 10 weeks (2-4 times/wk) of JR training, in place of 5 minutes of regular warm-up activities, was effective in improving 3-km time-trial performance, jumping ability, RSI, and arch stiffness in amateur endurance runners. Improvements in RSI and arch stiffness were associated with improvements in 3-km time-trial performance.

Agreement between the spatiotemporal gait parameters from two different wearable devices and high-speed video analysis.

This study aimed to evaluate the concurrent validity of two different inertial measurement units for measuring spatiotemporal parameters during running on a treadmill, by comparing data with a high-speed video analysis (VA) at 1,000 Hz. Forty-nine endurance runners performed a running protocol on a treadmill at comfortable velocity (i.e., 3.25 ± 0.36 m.s-1). Those wearable devices (i.e., Stryd™ and RunScribe™ systems) were compared to a high-speed VA, as a reference system for measuring spatiotemporal parameters (i.e. contact time [CT], flight time [FT], step frequency [SF] and step length [SL]) during running at comfortable velocity. The pairwise comparison revealed that the Stryd™ system underestimated CT (5.2%, p < 0.001) and overestimated FT (15.1%, p < 0.001) compared to the VA; whereas the RunScribe™ system underestimated CT (2.3%, p = 0.009). No significant differences were observed in SF and SL between the wearable devices and VA. The intra class correlation coefficient (ICC) revealed an almost perfect association between both systems and high-speed VA (ICC > 0.81). The Bland-Altman plots revealed heteroscedasticity of error (r2 = 0.166) for the CT from the Stryd™ system, whereas no heteroscedasticity of error (r2 < 0.1) was revealed in the rest of parameters. In conclusion, the results obtained suggest that both foot pods are valid tools for measuring spatiotemporal parameters during running on a treadmill at comfortable velocity. If the limits of agreement of both systems are considered in respect to high-speed VA, the RunScribe™ seems to be a more accurate system for measuring temporal parameters and SL than the Stryd™ system.

Creativity and physical fitness in primary school-aged children.

BACKGROUND: The aim of this study was to analyze the relationship between creativity and physical fitness in elementary school children. METHOD: Data were collected from 308 primary school students in southern Spain, ranging in age from 8 to 12 years (mean, 9.72 ± 1.25 years). They completed a fitness test battery, and the Prueba de Imaginación Creativa para Niños (PIC-N; Creative Imagination Test for Children) to analyze creativity. RESULTS: Significant differences were found between the sexes. Boys had better physical fitness but there were no sex differences in creativity. On clusters analysis, the highly creative groups had better physical fitness. Creativity was correlated with physical fitness. Aerobic capacity was a predictor of creativity. CONCLUSION: There is an association between creativity and physical fitness in primary school children that may have important implications for academic achievement.

Factores psicoeducativos que determinan la propensión al accidente deportivo en escolares: Diseño y validación de un cuestionario de evaluación / Psychoeducational factors that determine the propensity to school sports accidents: Design and validation of an assessment questionnaire

El propósito de este estudio ha sido el diseño y validación de una escala de propensión al accidente deportivo en escolares. La muestra ha estado formada por 254 niños (M = 14.20, DT = 1.3). Las propiedades psicométricas de la escala se obtuvieron mediante un proceso de validez de contenido y un análisis factorial de los componentes principales. Como resultados obtuvimos un cuestionario de 27 ítems formado por cinco factores y ajustado a los tópicos de validez y fiabilidad científica. Se encontraron diferencias en todos los factores de la escala entre niños y niñas y sólo en el factor búsqueda de sensaciones al considerar la edad de los sujetos. Como conclusión, esta escala es un instrumento inédito que permite la organización de los recursos materiales y didácticos en el deporte de acuerdo a aspectos psicoeducativos relacionados con la propensión al accidente de los niños, lo que es esencial en la prevención de lesiones (AU)

The purpose of this study has been the design and validation of a propensity scale of sports injuries in schools. The sample for the study has been formed of 254 children (M = 14.20, DT = 1.3). Psychometric properties of the scale were obtained through a process of content validity and a factorial analysis of main components. As a result, we obtained a questionnaire of 27 items consisting of 5 factors and adjusted to validity topics and scientific reliability. Significant differences were found in all factors of the scale in relation to sex, whilst significant differences were only observed in relation to the sensation seeking factor when considering the age of the subjects. This scale is an essential tool for preventing accidents and injuries in school sport by allowing the identification of sports accident-prone students (AU)

Diseño y validación de un cuestionario de propensión al accidente deportivo (PAD-22) / Design and validation of a propensity to sports accident questionnaire (PAD-22) / Desenho e validação de um questionário de propensão ao acidente esportivo (PAD-22)

El propósito de este estudio ha sido el diseño y validación de una escala de propensión al accidente deportivo en deportistas. La muestra ha estado formada por 118 deportistas (22.42±4.01 años). Las propiedades psicométricas de la escala se obtuvieron mediante un proceso de validez de contenido, concurrente con escala SSS-V y un análisis factorial de los componentes principales. Como resultados obtuvimos un cuestionario de 22 ítems formado por cinco factores y ajustado a los tópicos de validez y fiabilidad científica. Se encuentran diferencias significativas (p<.05) por deporte practicado y sexo en la escala PAD-22 y SSS-V (AU)

The purpose of this study was to design and validate a scale of the accident prone sports athletes. The sample has been formed by 118 athletes (22.42 ± 4.01 years old). The psychometric properties of the scale were obtained through a content validity´s process, concurrent validity with the scale SSS-V and factorial analysis of main components. As a result we obtained a 22-item questionnaire formed by five factors and adjusted to scientific validity and reliability´s topics. They found significant differences (p <.05) and gender in sport practiced on the scale PAD-22 and SSS-V (AU)

O propósito desse estudo foi de desenhar e validar uma escala de propensão ao acidente esportivo em esportistas. A mostra foi formada por 118 esportistas (22.42±4.01 anos de idade). As propriedades psicrométricas da escala foram obtidas mediante um processo de validação do conteúdo, concorrente com a escala de SSS-V e um analise fatorial dos componentes principais. Como resultado obtivemos um questionário de 22 itens formado por cinco fatores e ajustado aos propósitos da validez e fiabilidade cientifica. Foram encontradas diferenças significativas (p<.05) por esporte praticado e sexo, na escala PAD-22 e SSS-V (AU)

Intervention for spanish overweight teenagers in physical education lessons.

Physical education is a favourable educational framework for the development of programmes aimed at increasing physical activity in children and thus reducing sedentarism. The progressive increase of overweight students demands global control and follow-up measurement of these behaviours in both in and out of school. The pedometer can be a useful tool in this field. It is easy to use and allow Physical Education (PE) departments to quantify their students' number of steps/day. The aim of this study was to determine the effect of a pedometer intervention on body fat and BMI levels in overweight teenagers. Besides, the effects of the programme are analysed according to two other variables: pedometer ownership and gender, distinguishing between out-of-school and school hours, weekdays and weekends. The sample comprises 112 overweight students (49 boys and 63 girls) from 5 secondary schools. Participants were asked to follow a physical activity programme consisting on a minimum of 12000 and 10000 steps/day for boys and girls, respectively. It also allowed them to get up to 2 extra points in their PE marks. Results were measured after 6 weeks of programme application as well as after 6 weeks of retention. Results revealed significantly reduced BMI in the teenagers with their own pedometer (p < 0.05). The difference observed in the number of steps/day between boys (12050) and girls (9566) was significant in all measured time periods (p < 0.05). Besides, both overweight boys and girls were observed to take 1000 steps/day less at weekends than in weekdays. Therefore, it is concluded that the proposal of 12000 and 10000 steps for overweight boys and girls, respectively, accompanied by a reinforcement programme in their final PE marks, seems sufficient to obtain significant BMI reductions. Besides, PE is shown a favourable framework for the proposal of pedometer-impelled weight loss programmes in overweight youth. Key pointsA programme of 12000 and 10000 steps for overweight boys and girls, respectively with reinforcement in physical education marks, the body mass index improves.Body mass index more reduced was in Spanish adolescent overweight that used their own pedometer.The steps/day between boys (12050) and girls (9566) with overweight was different (p < 0.05).Overweight boys and girls were observed to take 1000 steps/day less at weekends than in weekdays.In physical education is possible to apply a programme of steps in obese youth of secondary education schools.