Visual Behaviours of Expert Padel Athletes When Playing on Court: An In Situ Approach with a Portable Eye Tracker.

Eye-tracking research has allowed the characterisation of gaze behaviours in some racket sports (e.g., tennis, badminton), both in controlled laboratory settings and in real-world scenarios. However, there are no studies about visual patterns displayed by athletes in padel. METHOD: The aim of this exploratory case study was to address the visual behaviours of eight young expert padel athletes when playing match games on a padel court. Specifically, their gaze behaviours were examined with an in situ approach while returned trays/smashes, serves, and volleys were performed by their counterparts. Gaze patterns were registered with an SMI Eye Tracking Glasses 2 Wireless. RESULTS: The participants' gaze was mainly focused on the ball-flight trajectory and on the upper body of the opponents because they were the two visual locations with a larger number of fixations and longer fixation time. No differences were found in these variables for each type of visual location when the three return situations were compared, or independently of them. CONCLUSIONS: Padel players displayed a similar gaze behaviour during different representative return situations. This visual pattern was characterised by fixating at the ball and some opponents' upper kinematics (head, shoulders, trunk, and the region of arm-hand-racket) to perform real interceptive actions while playing against them on a padel court.

Exploring Game Dynamics in Padel: Implications for Assessment and Training.

Courel-Ibáñez, J, Sánchez-Alcaraz Martinez, BJ, and Muñoz Marín, D. Exploring game dynamics in padel: implications for assessment and training. J Strength Cond Res 33(7): 1971-1977, 2019-A better understanding of in-game competition demands potentially improved coaching strategy and quality. However, there is very limited information about game patterns in padel, a very modern racket sport born in the 70s. The purpose of this study was therefore to quantify and classify game dynamics during the match in professional padel players through a multivariate decision tree approach including technical, spatial, and effectiveness indicators. The results determined 3 main game styles strongly defined by the court zone (net, middle, and baseline). In addition, particular technical, spatial, and effectiveness indicators were identified in each zone. In net and middle areas (offense) stood the use of volleys and overhead strokes on the center lane to both keep a positional advantage and solve the point. Conversely in the baseline (defense), the use of corner side walls and the domain of lobs showed to be relevant. The high rate of backhand groundstrokes, involving over 4 of 10 actions, is also remarkable. This information may have relevant implications for coaches working in padel by providing a novel hierarchically organization of game dynamics, which helps in designing training and conditioning programs close to real competitive situations.

Acute effect of a maximum incremental test until exhaustion on malondialdehyde and antioxidant vitamins in plasma and erythrocytes in athletes.

INTRODUCTION: Background: it is well known that moderate or vigorous physical exercise produces an increase in free radicals. Aim: the aims of this study were to observe changes in malondialdehyde and antioxidant vitamins after a maximum incremental test, and to relate malondialdehyde and antioxidant vitamin values to performance parameters. Methods: eighty-four male athletes participated in this study. Participants performed a maximum incremental test until exhaustion on a treadmill. Malondialdehyde in plasma and antioxidant vitamins in plasma and erythrocytes were determined before and after the test. Results: in plasma, there was a decrease in malondialdehyde after the test. In erythrocytes, results showed increases in vitamin C and decreases in vitamin E after the test. Maximal oxygen uptake values were associated positively with vitamin C and negatively with malondialdehyde levels before the test. On the other hand, maximal oxygen uptake, total test time, and total test distance were positively related to the malondialdehyde values obtained after the test. Conclusions: a maximum incremental test did not produce any changes in plasma vitamins in athletes. However, it increased the levels of vitamin C in erythrocytes and decreased malondialdehyde values in plasma and vitamin E in erythrocytes. The levels of malondialdehyde, vitamin C and vitamin E were related to performance parameters. These results may be linked to the adaptation of antioxidant systems due to regular training.

INTRODUCCIÓN: Introducción: es sabido que el ejercicio físico moderado o vigoroso produce un aumento de radicales libres. Objetivos: los objetivos del estudio fueron: observar los cambios del malondialdehído y las vitaminas antioxidantes después de un test incremental máximo y relacionar los niveles de malondialdehído y vitaminas antioxidantes con parámetros de rendimiento. Métodos: ochenta y cuatro atletas masculinos participaron en el estudio. Los participantes realizaron un test incremental hasta la extenuación en un tapiz rodante. El malondialdehído en plasma y las vitaminas antioxidantes en plasma y en eritrocitos se determinaron antes y después del test incremental. Resultados: en el plasma hubo una disminución del malondialdehído después de la prueba incremental. En los eritrocitos, los resultados mostraron un aumento de la vitamina C y un descenso de la vitamina E después de la prueba. El consumo máximo de oxígeno se asoció positivamente con la vitamina C e inversamente con el malondialdehído antes del test. Por otro lado, el consumo máximo de oxígeno, el tiempo total del test y la distancia total durante el test se asociaron positivamente con los valores de malondialdehído obtenidos tras el test máximo. Conclusión: un test incremental máximo hasta la extenuación no produjo cambios en las vitaminas antioxidantes del plasma. Sin embargo, sí aumentó los niveles de vitamina C en los eritrocitos y redujo los niveles de malondialdehído en el plasma y los de vitamina E en los eritrocitos. Los niveles de malondialdehído, vitamina C y vitamina E se relacionaron con los parámetros de rendimiento. Estos resultados podrían estar relacionados con la adaptación de los sistemas antioxidantes debido al entrenamiento regular.

[Influence of soccer training on parameters of oxidative stress in erythrocytes]. / Influencia del entrenamiento en fútbol sobre parámetros de estrés oxidativo en eritrocitos.

INTRODUCTION: Introduction: the situations of stress among which physical exercise is included imply the possibility of an excessive production of free radicals and, by their action, an oxidative stress in the cells. To combat these effects, cells have defense mechanisms called antioxidant systems. Objectives: the objective of this study is to analyze the possible physiological changes in relation to parameters related to oxidative stress (MDA) and antioxidant activity (vitamin A, vitamin C and vitamin E) in the erythrocytes of professional soccer players, in comparison with untrained subjects. Methods: forty-two men divided into 21 soccer players (SG) (24.95 ± 3.03 years) and 21 sedentary students (CG) (23.71 ± 2.42 years) participated in the study. Their basal levels of MDA, vitamin C, vitamin A and vitamin E in erythrocytes, as well as their anthropometric characteristics and VO2max, were evaluated. Results: significant differences were observed in the anthropometric characteristics (p < 0.05) and VO2max (p > 0.01). SG presented statistically lower levels of MDA (p > 0.01), vitamin C (p > 0.05), vitamin E (p > 0.05) and vitamin A (p > 0.01). Conclusions: there is higher oxidative stress in soccer players than in sedentary players and it may be necessary to supplement with antioxidants in this group.

INTRODUCCIÓN: Introducción: cualquier situación de estrés, entre las cuales se incluye la realización de ejercicio físico, implica la posibilidad de una excesiva producción de radicales libres y, por acción de estos, un estrés oxidativo en las células. Para combatir estos efectos, las células disponen de unos mecanismos de defensa denominados sistemas antioxidantes. Objetivos: el objetivo del presente estudio se basa en analizar los posibles cambios fisiológicos en relación a parámetros relacionados con el estrés oxidativo (MDA) y con la actividad antioxidante (vitamina A, vitamina C y vitamina E) en los eritrocitos de jugadores profesionales de fútbol, en comparación con sujetos no entrenados. Métodos: cuarenta y dos varones divididos en 21 jugadores de fútbol (SG) (24,95 ± 3,03 años) y 21 estudiantes sedentarios (CG) (23,71 ± 2,42 años) participaron en el estudio. Se les evaluaron los niveles basales de MDA, vitamina C, vitamina A y vitamina E en eritrocitos, así como las características antropométricas y el VO2max. Resultados: se observaron diferencias significativas en las características antropométricas (p < 0,05) y VO2max (p > 0,01). SG presentó niveles estadísticamente inferiores de MDA (p > 0,01), vitamina C (p > 0,05), vitamina E (p > 0,05) y vitamina A (p > 0,01). Conclusiones: existe un mayor estrés oxidativo en jugadores de fútbol que en sedentarios, por lo que puede ser necesaria una suplementación con antioxidantes en este grupo.

Oxidative stress, lipid peroxidation indexes and antioxidant vitamins in long and middle distance athletes during a sport season.

BACKGROUND: The main objective of this study was to observe any changes and possible adaptations produced in MDA and antioxidants vitamins on plasma and erythrocytes in endurance male athletes among an athletic season (12 months). METHODS: Twenty three long and middle distance male athletes participated in this study. Basal MDA on plasma and antioxidant vitamins in plasma and erythrocytes were measured at four moments along the season (0, 3, 6 and 9 months). Fatty acid concentrations in erythrocytes were obtained to determine lipid peroxidation indexes. RESULTS: In plasma, vitamin C suffered significant decreases at 3 and 6 months compared with the begin (P<0.01), and an increase at 9 months, compared with 3 months. On the other hand, vitamin A level was significantly lower at 9 months compared with the other periods (P<0.01 compared with 0 and 6 months; P<0.05 compared with 3 months). In erythrocytes, significant decreases were observed in vitamin E among the season at 6 months and an increase from 6 to 9 months (P<0.05). Vitamin A suffers a significant decrease in both for competitive periods, at 3 and 9 months, compared with the beginning of the season. The most of changes in lipid peroxidation indexes were produced along the firsts 3 months. CONCLUSIONS: 1) Physical training improves the antioxidant systems in order to reduce lipid peroxidation in trained athletes along the season; 2) PUFA/SFA ratios seem more reliable than MDA to observe oxidative stress.

[Comparative study of the variables of physical fitness and health among young athletes and sedentary males]. / Estudio comparativo de las variables determinantes de la condición física y salud entre jóvenes deportistas y sedentarios del género masculino.

INTRODUCTION: today, the practice of physical activity during adolescence brings important physical-health benefits that help develop a future well-being in later life. OBJECTIVES: the objective of this comparative study was to evaluate the physical condition, body composition and cardiorespiratory capacity among young athletes and sedentary people of the Autonomous Community of Extremadura (Spain). METHODS: two hundred and twenty-five male subjects, aged between 12 and 18 years, were divided into two groups: 175 athletes, divided into aerobic group (AEG), anaerobic group (ANAEG) and mixed sports group (MG); and 50 sedentary (SG) or control group. Their respiratory capacity (forced expiratory volume [FEV], peak expiratory flow [PEF], vital capacity [VC], maximum voluntary ventilation [MVV]) and body composition were assessed. They also performed the "Forest Service" step test by finding the VO2max. Also, the heart rate (HR) was recorded before the step, the maximum heart rate during the test and the HR in the subsequent recovery, as well as pre and post-test blood pressure. RESULTS: there were significant differences in body composition, blood pressure, heart rate and respiratory capacity in relation to athletes compared to the control group (p < 0.05). CONCLUSIONS: physical activity provides benefits in aspects such as body composition, and cardio-respiratory function.

Análisis nutricional en atletas de fondo y medio fondo durante una temporada deportiva.

Objetivo: el objetivo de este estudio fue analizar la ingesta nutricional de atletas de alto nivel de las especialidades de fondo y medio fondo, durante una temporada atlética, para detectar posibles deficiencias.Métodos: para llevar a cabo el estudio, se procedió a evaluar la dieta y las diferentes concentraciones de los macronutrientes (glúcidos, lípidos y proteínas) y los diferentes tipos de ácidos grasos, en cuatro momentos diferentes de la temporada: al inicio y a los 3, 6 y 9 meses de entrenamiento. La muestra estuvo constituida por un grupo formado por 23 atletas de fondo y medio fondo con un mínimo de 5 años de ntrenamiento, una carga semanal de entre 14-20 horas y un volumen de 100-120 km semanales. El procedimiento consistió en el registro nutricional durante un periodo de tres días consecutivos, en los cuatro momentos establecidos.Resultados: los resultados obtenidos muestran incrementos significativos (p < 0,05) en la ingesta de proteínas entre los 3-9 meses.Conclusión: la ingesta energética en atletas de fondo y medio fondo va aumentando a lo largo de la temporada deportiva, con cantidades de macronutrientes inferiores a las recomendadas por la comunidad científica, y con incrementos en la ingesta de proteínas en periodos de primavera y verano, coincidiendo con momentos de competición.

Efectos de un protocolo de ayuno intermitente sobre la composición corporal y perfil lipídico en estudiantes universitarios / Effects of a protocol of intermittent fasting on body composition and lipids profile in university students

El ayuno intermitente es una estrategia nutricional de creciente interés para el control del peso y mejora de la salud metabólica. El objetivo del presente estudio fue evaluar el efecto de un protocolo de ayuno intermitente sobre la composición corporal, perfil lipídico y los biomarcadores de riesgo cardiovascular en estudiantes universitarios. En este estudio experimental participaron 30 sujetos varones y fueron divididos aleatoriamente en dos grupos, 15 sujetos constituían el grupo experimental (GE) (edad: 20,83±0,98 años) y 15 el grupo control (GC) (edad: 23,71±5,55 años). El GE realizó un protocolo de ayuno 16/8, dieciséis horas de ayuno y ocho horas de ingesta calórica sin limitaciones, dos días consecutivos a la semana durante cinco semanas. Se evaluó la composición corporal, la ingesta calórica, el perfil lipídico y los biomarcadores del riesgo cardiovascular al inicio, mitad y final del protocolo. Se observaron descensos significativos en el GE en pliegues cutáneos, perímetro cintura, porcentaje de grasa, perfil lipídico y biomarcadores del riesgo cardiovascular en comparación con GC (p<0,05). Se encontraron incrementos significativos en la ingesta de colesterol y ácidos grasos poliinsaturados en el GE al final del estudio (p<0,05). Se observaron descensos en el colesterol total, triglicéridos, lipoproteínas de baja densidad y biomarcadores del riesgo cardiovascular a lo largo del protocolo en el GE (p<0,05). Un protocolo de ayuno intermitente 16/8, dos días consecutivos por semana, durante cinco semanas, parece efectivo para mejorar parámetros de composición corporal y perfil lipídico, así como para mejorar los biomarcadores relacionados con el riesgo cardiovascular(AU)

Intermittent fasting is a nutritional strategy of high interest in weight control and improvement of metabolic health. The objective of this study was to evaluate the effect of an intermittent fasting protocol on body composition, lipid profile and biomarkers of cardiovascular risk in university students. In this experimental study thirty male subjects participated and were randomly divided into two groups; fifteen subjects constituted the experimental group (GE) (age: 20.83 ± 0.98 years) and fifteen the control group (GC) (age: 23.71 ± 5.55 years). The GE performed a fasting protocol 16/8, sixteen hours of fasting and eight hours of caloric intake without limitations, two consecutive days per week for five weeks. Body composition, calorie intake, lipid profile and biomarkers of cardiovascular risk were evaluated at the beginning, middle and at the end of the protocol. Significant decreases were found in GE in skinfolds, waist perimeter, % fat, lipid profile and biomarkers of cardiovascular risk as compared to GC (p <0.05). There were significant increases in the intake of cholesterol and polyunsaturated fatty acids in the GE at the end of the study (p <0.05). There were decreases in total cholesterol, triglycerides, low-density lipoproteins, and biomarkers of cardiovascular risk throughout the study in GE (p<0.05). An intermittent fasting protocol 16/8, two consecutive days per week, for five weeks, seems effective to improve parameters of body composition and lipid profile, as well as to improving biomarkers related to cardiovascular risk(AU)