Reliability and Validity of the Polar V800 Sports Watch for Estimating Vertical Jump Height.

This study aimed to assess the reliability and validity of the Polar V800 to measure vertical jump height. Twenty-two physically active healthy men (age: 22.89 ± 4.23 years; body mass: 70.74 ± 8.04 kg; height: 1.74 ± 0.76 m) were recruited for the study. The reliability was evaluated by comparing measurements acquired by the Polar V800 in two identical testing sessions one week apart. Validity was assessed by comparing measurements simultaneously obtained using a force platform (gold standard), high-speed camera and the Polar V800 during squat jump (SJ) and countermovement jump (CMJ) tests. In the test-retest reliability, high intraclass correlation coefficients (ICCs) were observed (mean: 0.90, SJ and CMJ) in the Polar V800. There was no significant systematic bias ± random errors (p > 0.05) between test-retest. Low coefficients of variation (<5%) were detected in both jumps in the Polar V800. In the validity assessment, similar jump height was detected among devices (p > 0.05). There was almost perfect agreement between the Polar V800 compared to a force platform for the SJ and CMJ tests (Mean ICCs = 0.95; no systematic bias ± random errors in SJ mean: -0.38 ± 2.10 cm, p > 0.05). Mean ICC between the Polar V800 versus high-speed camera was 0.91 for the SJ and CMJ tests, however, a significant systematic bias ± random error (0.97 ± 2.60 cm; p = 0.01) was detected in CMJ test. The Polar V800 offers valid, compared to force platform, and reliable information about vertical jump height performance in physically active healthy young men.

Efectos regulares en la cognición de los descansos activos / Chronic effects in cognition of actives-breaks

En el presente artículo se investigaron los efectos de un programa de entrenamiento físico de una duración de ocho semanas sobre la cognición del alumnado de 1º de Bachillerato. Para lograr nuestro objetivo, dispusimos de dos grupos (Grupo control Vs Grupo experimental). Mientras, que el grupo control no realizó el entrenamiento, el grupo experimental realizó dos descansos activos a lo largo de una jornada escolar (1º A las 10:00 a.m. y 2º A las 12:30 p.m.). Antes de comenzar la intervención, en la primera semana, se tomaron los datos ambos grupos (pre). La intervención demostró su eficacia a nivel cognitivo, concretamente en atención sostenida. Por tanto, los resultados fueron coincidentes con la mayor parte investigaciones encontradas en la literatura sobre ejercicio físico regular y efectos positivos sobre las funciones cognitivas

The present paper investigated the effect of a physical training program of 8-weeks on cognition of students of firs of high school To achieve or goal, we work with two groups (Control Group Vs Experimental Group). Control group did not to the intervention, the experimental group performed two active breaks during the school day (1 at 10:00 a.m. and 2 12:30 a.m.). Before to start the intervention, in first week, both groups (pre-intervention) data were registered. The intervention demonstrated its effectiveness at cognitive level, concretely in sustained attention. Therefore, results were consistent with most research found in the literature on regular physical exercise and positive effects on cognitive functions