Javier Sánchez

Pontifical University of Salamanca | UPSA · Departamento de Ciencias de la Actividad Física y del Deporte

The study aimed to assess the immediate effects of re-warm-up strategies using half-squats with elastic looped bands on the performance of youth soccer players. A cross-over study design with repeated measures was implemented in field youth male soccer players (n = 20, age 15.7 ± 0.8 years). Following the first 45-min of match play, players were su...

El objetivo principal de este estudio fue de analizar los efectos del desentrenamiento en función del nivel inicial de condición física determinado a través del Total Score of Athleticism (TSA) en jugadoras de fútbol. Catorce jugadoras de fútbol realizaron una evaluación pre y post periodo de desentrenamiento (i.e., 2 semanas) consistente en un tes...

We aimed to (1) compare external training loads obtained in futsal players during pre-season and in-season training weeks to explore how these loads are periodized by the coaching staff; and (2) compare the external training loads using the match day minus approach during the pre-season and in-season periods to determine how the within-microcycle t...

Basketball demands a sophisticated blend of tactical, technical, physical, and psychological skills, and various methods have been proposed to prepare players for these demands, including re-sistance training to enhance strength, power, speed, agility, and endurance. Complex training (CT) integrates diverse strength training methodologies by combin...

Objective: To analyze the effect of activation throughbilateral or unilateral strength and plyometric exercises onhorizontal jump performance. Methodology: The studyinvolved 15 highly trained male soccer players (age, 24.7± 3.1 years; height, 181.2 ± 4.7 cm; weight, 79.7 ± 3.4 kg)from the same team competing in the national league.Their regular tra...

Objetivo: Analizar el efecto de una activación realizada a través de ejercicios de fuerza y pliometría ejecutados de forma bilateral o unilateral sobre el rendimiento en salto horizontal. Metodología: En el estudio participaron 15 futbolistas masculinos, altamente entrenados (edad, 24.7 ± 3.1 años; altura, 181.2 ± 4.7 cm; peso, 79.7 ± 3.4 kg) pert...

Background Maximal strength may contribute to soccer players’ performance. Several resistance training modalities offer the potential to improve maximal strength. During recent years, a large number of plyometric jump training (PJT) studies showed evidence for maximal strength improvements in soccer players. However, a comprehensive summary of the...

The aim was to analyze the effect of two activation protocols based on exercises with bodyweight and elastic bands on the improvement of muscle power. Ten male university students of Physical Activity and Sports Sciences (age: 23.1±1.5 years) randomly completed with 48 hours of recovery between sessions, a control situation without warm-up (CON) an...

The aim was to analyze the effect of two activation protocols based on exercises with bodyweight and elastic bands on the improvement of muscle power. Ten male university students of Physical Activity and Sports Sciences (age: 23.1±1.5 years) randomly completed with 48 hours of recovery between sessions, a control situation without warm-up (CON) an...

Background: Small-sided games (SSG) are among the most frequently used training drill in soccer. Aim: to investigate if the type of game (i.e., game with goalkeepers vs. possession games without goalkeepers) and wildcard type (i.e., without vs. internal vs. external wildcard) impact the physiological (i.e., heart rate) and locomotor (i.e., total d...

Objective: To compare the physical performance and official match demands of soccer players following a warm-up session that involved small-sided games with weighted vests of varying loads. Equipment and methods: This study involved fifteen highly trained male soccer players (age: 17.8 ± 0.5 years; height: 173.4 ± 6.3 cm; body mass: 66.1 ± 7.4 kg;...

Purpose: To compare the effects of unilateral flywheel training (FT), using a rotational conical pulley, including multidirectional movements with either preplanned or random unanticipated/unexpected executions on functional performance in football players. Methods: A total of 32 young male football players were randomly assigned to an FT program i...

BACKGROUND: Education level is an item that is not usually considered when talking about injury prevention and treatment in football. Different education levels can influence the perception of the players about their careers and in consequence the risks they take in the field, and no studies are found about this influence. Injuries are considered i...

Purpose This study compares the effects of 6 weeks of pre-season cardiopulmonary- vs. neuromuscular-based high-intensity interval training (HIIT) in female basketball players’ physical fitness. Methods Overall, 16 female regional-level U19 basketball players were randomly allocated to a cardiopulmonary-based HIIT (C-HIIT) group ( n = 8; age: 17.9...

El objetivo fue analizar el efecto de la edad sobre las demandas físicas y fisiológicas de juegos reducidos con diferente espacio individual de interacción. Treinta jugadores de edad sub-12 (U12: n=10; edad, 11.2  0.8 años; altura, 145.4  6.4 cm; masa corporal, 37.5  3.9 kg), sub-14 (U14: n=10; edad, 13.5  0.6 años; altura, 163.7  5.9 cm; masa...

This study aimed to analyze the effects of a 16-week jump training program on the physical performance and lower extremities injury profile in semi-professional male soccer players. Participants were randomly assigned to the control group (CG; n=13; age = 21.7 ± 3.6 years) or the experimental group (EG; n=10; age = 22.3 ± 3.5 years). Countermovemen...

Background Youth female soccer players require high muscular power to overcome their opponents. Jump training can facilitate improvements in muscular power as has been demonstrated in youth male soccer players. However, studies in female players are comparatively scarce. Objective The aim of this study was to assess the effects of a jump-training...

El objetivo de este estudio fue analizar el valor de mercado (VM) de futbolistas profesionales de las 5 mejores ligas europeas de fútbol. Se analizó el efecto de las variables independientes sobre el VM de los futbolistas, mediante una ANOVA con un nivel de significación de p <0.01. Los futbolistas de la Premier League (PL) mostraron mayor VM en co...

We aimed to assess the effects of plyometric jump training (PJT) on female soccer player’s physical fitness. To this aim, a systematic review with meta-analysis (SRMA) was conducted. The electronic databases PubMed, MEDLINE,Web of Science, and SCOPUS were used. To qualify for inclusion, peer-reviewed studies must have included (i) a PJT programme o...

Repeated sprint training appears to be an efficient strategy for the simultaneous development of different fitness components in intermittent sport. The aim of this study was to analyze the effects of implement training with repeated sprint training on repeated sprint ability (RSA), reaction time in fatigue condition and jump height. Twenty-seven y...

The aim of this study was to quantify the acute impact of bouts duration and individual interaction space on physical and physiological demands and on physical performance. Ten young male soccer players (age: 14.8 ± 0.6 years) from the same team playing in the National U-16 Division participated. Physical (total distance [TD]; distance covered at d...

This study analyzed the effects of a training program based on Nordic Hamstring and sprint exercises on physical performance and hamstring injuries in young male soccer players. Forty-nine U19 players were randomly assigned to a control (CG; n = 26) or experimental group (EG; n = 23). Linear sprint and with change of direction (COD) were assessed b...

This study examined the effects of body mass-based resistance training (bmRT) on selected measures of physical fitness and injury incidence and burden in soccer players. Forty-six U16 male soccer players were randomly assigned to an control (CG; n = 26) or experimental group (EG; n = 20) Countermovement jump (CMJ), change of direction (CoD) (i.e.,...

Recent classifications of resistance training methods classify them in gravitational, to move the resistance we will have to apply an acceleration greater than the force of the gravity (9.81 m·s⁻¹), and non-gravitational methods that allow us to work in multiple directions, not being exclusively conditioned by gravity. Bodyweights training, also kn...

The aim of the study was to analyze variations in performance and subjective perception of well-being in young soccer players between menstrual (FM), follicular (FF) and luteal (FL) phases. Twelve female soccer players participated (16.18 ± 1.68 years; 164 ± 7.27 cm; 61.90 ± 6.37 kg) with 4 years of competitive experience and 3.1 ± 1 years with reg...

Efectos de un programa de entrenamiento basado en nordic hamstring vs programa de entrenamiento basado en sprints en jugadores jóvenes de fútbol. Resumen: El objetivo del presente estudio es analizar el efecto de dos programas de entrenamiento, Nordic Hamstring (NH) y Sprint (SP) sobre la condición física en jugadores jóvenes de fútbol. Participaro...

Small-sided games (SSGs) are a useful strategy to optimize the training process in soccer. The modification of some variables simultaneously implies several physical adaptations in soccer players. Thus, the aim of this study was to analyze the differences in the physical demands encountered by soccer players in different SSGs formats focusing on th...

Small-sided games (SSGs) are a useful strategy to optimize the training process in soccer. The modification of some variables simultaneously implies several physical adaptations in soccer players. Thus, the aim of this study was to analyze the differences in the physical demands encountered by soccer players in different SSGs formats focusing on th...

El objetivo de este estudio fue comparar la carga externa de las sesiones de un microciclo de entrenamiento en un equipo de fútbol semiprofesional, teniendo en cuenta el rol del jugador durante la competición y la localización del partido. Dieciocho futbolistas que competían en la tercera división española fueron monitorizados mediante sistemas de...

The aim of this study was to compare the external loads (i.e., displacement distances and velocities) of 10–11 years-old soccer players during Soccer-7 (i.e., seven-a-side), Soccer-8 (i.e., eight-a-side), and Soccer-11 (i.e., eleven-a-side) official matches. Male athletes (n = 133; age, 10.9 ± 0.8 years) were measured during official matches for to...

Background: This study aimed to quantify internal training load and changes in vertical jumping ability and endurance capacity of professional volleyball players during the preseason, and to explore relationships between players` physical qualities at the beginning of the preseason with internal training load accumulated during the first two weeks...

Background The aim of this study is to conduct a systematic review with meta-analysis to explore the effects of plyometric jump training (PJT) on the physical fitness of individual sport athletes (ISA). Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched through PubMed, Web of Science, a...

The aim of this study was to examine the effects of short-term (six weeks) preseason strength and jumping exercises distribution program on amateur adult soccer player’s indicators of physical fitness. Twenty male athletes (age 20.1±1.6 years) were randomly divided into two groups that completed a volume-equated training program differing only in e...

The aim of this study was to compare the effects of different warm-up conditioning intensities on the physical fitness (i.e., post-activation potentiation -PAP), of professional male field soccer players. Athletes (n = 10; age: 21.6 � 3.2 years) completed a control warm-up and warm-ups aimed to induce PAP, in random and counterbalanced order. After...

We aimed to assess the effects of plyometric jump training (PJT) on female soccer player’s physical fitness. To this aim, a systematic review with meta-analysis (SRMA) was conducted. The electronic databases PubMed, MEDLINE, Web Of Science, and SCOPUS were used. To qualify for inclusion, peer-reviewed studies must have included i) a PJT programme o...

Female family caregivers (FFCs) constitute one of the basic supports of socio-health care for dependence in developed countries. The care provided by FFCs may impact their physical and mental health, negatively affecting their quality of life. In order to alleviate the consequences of providing care on FFCs, the Spanish Public Health System has dev...

Eating disorders are associated with short and long-term consequences that can affect sports performance. The purposes of this study were to investigate whether female athletes, particularly gymnasts and footballers, exhibit more eating problems compared to female non-athletes, and to identify individual personality characteristics including anxiet...

Eating disorders are associated with short and long-term consequences that can affect sports performance. The purposes of this study were to investigate whether female athletes, particularly gymnasts and footballers, exhibit more eating problems compared to female non-athletes, and to identify individual personality characteristics including anxiet...

El objetivo fue analizar la influencia de las modalidades fútbol 7 (F7), fútbol 8 (F8) y fútbol 11 (F11) en categoría alevín, sobre el clima y orientación motivacional y el grado de diversión. 377 jugadores (10,910,76 años) completaron los cuestionarios PMCSQ-2, POSQ y CDPD. En todas las modalidades se obtuvieron valores altos para clima motivacio...

To assess the effects of plyometric jump training (PJT) in female soccer player’s vertical jump height, a review was conducted using the data sources PubMed, MEDLINE, Web Of Science, and SCOPUS. Only peer-review articles were included. To qualify for inclusion in the meta-analysis, studies must have included i) a PJT programme of at least 2 weeks,...

The aim of the study was to analyze the influence of the game modalities applied to the soccer competition in U-12 category on the technical-tactical demand. During the 2016-2017 season, 18 men's soccer matches in Spain were analyzed, 6 by modality (eleven-a-side, n = 6; seven-a-side, n = 6; eight-a-side, n = 6), recording a total of 7.275 technica...

Background: The aims of this study were: 1) to compare anthropometric and fitness variables of high-level beach handball players across Under-19 (U-19), Under-21 (U-21) and senior male categories, and between male and female senior players and; 2) to test the correlations among those measures. Methods: A total of 70 high-level players (53 male o...

El objetivo del presente estudio fue analizar el efecto de cuatro protocolos de activación pre-competición basados en contracciones excéntricas sobre el tiempo en 25-m de estilo libre en natación. Diez nadadores (20,8  4,7 años de edad; 175,2  9,3 cm de altura; 66,4  10,4 kg de peso) que competían en categoría nacional participaron en el estudio...

El objetivo de este estudio fue analizar la respuesta física de árbitros de fútbol 11 (AC11), asistentes de fútbol 11 (AA11) y árbitros de fútbol 7 (AC7) durante partidos oficiales, atendiendo a rangos absolutos de velocidad y al pico máximo de velocidad (Velmax) individualizado. En este estudio participaron 26 árbitros (25,6  4,7 años) los cuales...

The aim of this study was to examine the effects of short-term (six weeks) preseason strength and jumping exercises distribution program on amateur adult soccer player's measures of physical fitness. Male athletes (age, 20.1±1.6 years) were randomly divided into groups that completed a volume-equated training program differing only in exercises dis...

The aim of this study was to analyse the effects of two short-term training programs to prevent the negative effect of detraining on repeated sprint ability (RSA) performance. The study was carried out during a 2-wk midseason break without official matches. Forty-five youth soccer players (17.7 ± 0.8 yr, 175.4 ± 5.5 cm and 67.2 ± 5.1 kg) were split...

Aerobic fitness is a decisive performance factor in soccer players. Previous studies have correlated the distance travelled in an intervallic test (Yo-Yo IR test) with the distance covered in competition, demonstrating that a high aerobic capacity contributes to better recovery in high intensity intermittent exercises typical of training and soccer...

Purpose: The aim of this study was to examine the short and long-term effects of a simple strength training program on muscle injury prevention in soccer players. Methods: Twenty-seven U-19 elite male soccer players participated in the study. The investigation was conducted over two consecutive and similar seasons (e.g. the same staff, players, wee...

The aim of the study was to analyze the influence of the game modalities applied to the soccer competition in U-12 category on the technical-tactical demand. During the 2016-2017 season, 18 men's soccer matches in Spain were analyzed, 6 by modality (eleven-a-side, n = 6; seven-a-side, n = 6; eight-a-side, n = 6), recording a total of 7.275 technica...

To examine the effects of 10 weeks (2/week) resistance training on stable vs. unstable surfaces on selected measures of physical performance in young male soccer players, national-level U19 players participated in this study. They were randomly allocated to an unstable resistance training group (uRT, n=27) or a stable resistance training group (sRT...

The aim of this study was to assess the effect of an 8-week repeated sprint with change of direction training program on repeated sprint, intermittent endurance and change of direction performance in youth soccer players with different aerobic fitness level. Athletes were randomly assigned into a soccer-only (n=9; age, 14.9±0.4 yr) and soccer plus...

El objetivo fue analizar la influencia de las modalidades de juego aplicadas a la competición en categoría sub-12 sobre el regate. Se analizaron 18 partidos, 6 por modalidad, registrando 785 regates. Las variables dependientes fueron regates realizados (RT), ganados (RG) y perdidos (RP). Se registraron en función a zonas del campo: pasillos lateral...

El objetivo de este estudio fue describir y analizar el porcentaje de goles conseguidos respecto al número de acciones de tiro a portería y la probabilidad de éxito, relacionados con demarcación del jugador, región corporal con la que se ejecuta la acción y contexto espacial desde donde se realiza. Se analizaron y registraron 733 acciones de tiro (...

Objetivo: Analizar el efecto del entrenamiento de pretemporada sobre la condición física de futbolistas jóvenes en función de la demarcación ocupada en el campo. Método: En el estudio participaron 31 futbolistas jóvenes (edad: 15.5 ± 0.7 años; altura: 174.4 ± 6.3 cm; peso: 62.4 ± 13.4 kg; experiencia: 8.5 ± 1.3 años) que fueron divididos en tres gr...

El objetivo de este trabajo fue analizar la demanda física y el comportamiento técnico-táctico de futbolistas que juegan partidos frente a rivales con diferente nivel de oposición. En el estudio participaron 20 futbolistas de categoría sub14 (n=10; 13.6 ± 0.5 años de edad; 163.7 ± 5.9 cm de altura; 51.5 ± 6.0 kg de masa corporal) y sub16 (n=10; 15....

El objetivo de este trabajo fue analizar la demanda física y el comportamiento técnico-táctico de futbolistas que juegan partidos frente a rivales con diferente nivel de oposición. En el estudio participaron 20 futbolistas de categoría sub14 (n=10; 13.6 ± 0.5 años de edad; 163.7 ± 5.9 cm de altura; 51.5 ± 6.0 kgde masa corporal) y sub16 (n=10; 15.8...

The aim of this study was to compare the effects of different warm-up conditioning intensities on the physical fitness (i.e., post-activation potentiation -PAP), of professional male field soccer players. Athletes (n = 10; age: 21.6 ± 3.2 years) completed a control warm-up and warm-ups aimed to induce PAP, in random and counterbalanced order. After...

El objetivo de este estudio fue analizar el efecto del tipo de metodología sobre el tiempo de compromiso motor, conocimiento del juego, demanda fisiológica y física y grado de diversión correspondientes a una unidad didáctica (UD) de fútbol-sala. En el estudio participaron 24 alumnos de primero de bachillerato, asignados de forma aleatoria a un gru...

The purpose of this study was to analyse the physical demands and technical-tactical performance of football players who play matches against opponents with a different level of opposition. The study included 20 players in the U14 (n = 10; age: 13.6 ± 0.5 years old; height: 163.7 ± 5.9 cm; weight: 51.5 ± 6.0 kg) and U16 (n=10; age: 15.8 ± 0.4 years...

The effects of plyometric jump training on the physical fitness of male youth (age = 10–17 years) soccer players was examined in relation to inter-set recovery intervals and the maturity of the players in a single-blind, randomized-and controlled crossover trial. Jumping tests and kicking velocities were measured before (T0), after a 6 week control...

Background: The external load associated with different formats of SSGs has been well studied, however it is necessary to know the effect of little-analyzed variables such as directionality or order in the training session. Objectives: The objective of this study was to compare the physical demands of soccer small-sided games (SSGs) performed under...

The aim of this study was to compare changes in young soccer player’s fitness after traditional bilateral vs. unilateral combined plyometric and strength training. Male athletes were randomly divided in two groups; both received the same training, including strength training for knee extensors and flexors, in addition to horizontal plyometric train...

Aim: The aim of this study was to assess the external load of amateur male players during 4 consecutive training microcycles (M) at the beginning of the in-season according to the training session in absolute external load demands and in relation to the competition demands. Methods: Regional-level players (n = 10; age, 20.8 ± 1.7 years; height, 17...

The aim of this study was to compare the activity profile (external loads) during soccer-7 competition versus 6 vs 6 small-sided games (SSGs) in U12 players. Peak velocity (Vmax), total distance completed (DT), total distance relative to match duration, the percentage of DT in acceleration (%DAC) and in deceleration (%DEA), and the percentage of DT...

The aim of the study was to compare the effects of an in-season five weeks of high-intensity training (HIT) with a concurrent HIT eccentric overload training (CT) program on male amateur team-sports players’ fitness performance. Twenty-two athletes were randomly assigned to HIT (n=10) or CT (n=12). Both groups completed a HIT program. The CT group...

To better understand the detraining effects in soccer, the purpose of the study was to analyse if performance level of soccer players modulate repeated-sprint ability (RSA) and intermittent endurance changes during 2-weeks of detraining (i.e., in-season break). Seventeen professional and sixteen young elite soccer players of two different teams per...