Scandinavian Journal of Medicine & Science in Sports, 2017
Article type : Original Article Serum IL-15 and IL-15Rα levels are decreased in lean and obese ph... more Article type : Original Article Serum IL-15 and IL-15Rα levels are decreased in lean and obese physically active humans.
Valadés, D., Palao, J.M. El radar como instrumento de control del entrenamiento RESUMEN El radar ... more Valadés, D., Palao, J.M. El radar como instrumento de control del entrenamiento RESUMEN El radar es un instrumento capaz de medir de forma directa e inmediata la velocidad de los objetos en movimiento en las actividades deportivas. Su empleo permite valorar de forma indirecta la fuerza que el deportista es capaz de transferir al móvil. Su uso no requiere colocar al deportista implementos externos. El presente trabajo muestra los conceptos y protocolos para el empleo del radar como elemento del control indirecto del trabajo de fuerza. Su utilización permitir controlar si las actividades realizadas dentro del entrenamiento son un estímulo adecuado para los deportistas a nivel de aplicación de fuerza. Su uso permitir integrar el trabajo realizado por los preparadores físicos con el trabajo realizado por los entrenadores, evolucionando de situaciones simplificadas a gestos específicos de juego en situaciones reales.
Official Drill Bulletin of the american VOlleyBall cOaches assOciatiOn | VOlume nO. 23, issue nO.... more Official Drill Bulletin of the american VOlleyBall cOaches assOciatiOn | VOlume nO. 23, issue nO. 5 PowerTips march 7, 2012 T he spike is the technical action that achieves the most points in the game . from the mechanical view point, there are three aspects that define spike success : a) hit height, b) ball speed, and c) ball direction. hit height depends on the technical execution of the spike and lower body strength. Ball speed depends on the technical execution of the spike and upper body strength. Ball direction depends on the technical and tactical execution of the spike. the focus of this article is on how to improve and monitor the speed of the spike.
The purpose of this study was to give reference values for serve speed peaks. A retrospective ana... more The purpose of this study was to give reference values for serve speed peaks. A retrospective analysis of the 10-20 fastest serves in men´s and women´s World Tour beach volleyball from the 2005 to the 2012 seasons was done. A total of 136 serves from the men´s competition and 141 serves from the women's competition was included in the study. The results show: 1) for males, the average serve speed peak was 98.3 ± 4.3 km·h-1, and the serve speed peak was 114.0 km·h-1; and 2) for females, the average serve speed peak found was 80.0 ± 2.7 km·h-1 and the serve speed peak was 86.5 km·h-1. No significant differences were found between the first four years and the next four years in the men´s competition, there were significant differences between the first four years and the second four years in the women´s competition. Significant differences were found between men and women in speed serve peaks. The data found can help coaches establish the reference values of serve speed for the pow...
International Journal of Performance Analysis in Sport
The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest time ... more The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest time for women's beach volleyball players in relation to their in-game role. The sample of this study was composed of 2,708 rallies played by 48 female beach volleyball players, which corresponded to 69 sets of the 2008 Olympic Games. The variables recorded were: ball contacts, jumps, hits, work time, rest time, and player's role (defense specialist, blocker, or no specialization). A significantly higher number of jumps were performed by blockers. No differences were found in the number of contacts or hits. The work : rest ratio was 1 : 5. This paper discusses how the data can be used to create game-like situations in practices regarding physical demands in women's beach volleyball.
The objectives of the present study were: a) to assess normative profiles for the serve speed of ... more The objectives of the present study were: a) to assess normative profiles for the serve speed of peak-performance volleyball players in order to guide practice sessions for men´s teams (study 1) and women´s teams (study 2), and b) to establish the possibilities and the ranges of speed that a volleyball throwing machine can offer for working on reception in volleyball (study 3).
The purpose of this paper was to study the ranges in height, weight, age, spike reach, and block ... more The purpose of this paper was to study the ranges in height, weight, age, spike reach, and block reach of volleyball players in relation to the player position and the level of their respective teams in peak performance. The analysed sample included 1454 male and 1452 female players who participated in the volleyball competitions of the Olympic Games and World Championships in the 2000-2012 period. A descriptive, correlational, and longitudinal design was used. The variables studied were: the player position, body height, weight, body mass index, spike reach, block reach, age, and team level. The results show differences between body height, spike and block reaches, and the age of the players by their position. These differences are related to the needs of the different positions with regard to the actions they execute. Middle-blockers, outside-hitters, and opposites have the characteristics that are most suitable for blocking and spiking, and the setters and liberos appear to have characteristics conducive to setting and receiving as well as digging, respectively. The differences found in the studied variables with regard to the playing position are related to players' needs regarding the actions they perform. Player´s age was a variable that differentiated first teams at this level of competition for males, and physical capacities (body height, weight, spike reach, and block reach) were variables that differentiated first teams at this level of competition for females.
The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest ratio... more The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest ratio in male beach volleyball players in relation to their tactical roles. The sample of this study included 6970 rallies played by 91 beach volleyball players, which corresponded to 179 sets of the 2008 Men's Beach Volleyball World Tour (FIVB). We analyzed: ball contacts, jumps, hits, work time, rest time, set (first, second or third), and player's tactical role (e.g., defense specialist, blocker, or no specialization). A significantly higher number of jumps were executed by blockers. No differences were found in the third set for any of the physical variables studied. This paper provides references about the physical demands (e.g., contacts, jumps, and hits for blockers and defense specialists) and temporal patterns of the beach volleyball game (i.e., work and rest time) for two-set matches and three-set matches.
After the 2000 Olympic Games, the Fédération Internationale de Volleyball (FIVB) modified the sco... more After the 2000 Olympic Games, the Fédération Internationale de Volleyball (FIVB) modified the scoring system used in beach volleyball from side-out to a rally point system. The goal was to facilitate the comprehension of the game and to stabilize match duration. The purpose of this study was to assess the duration and number of rallies in men´s and women´s beach volleyball matches ). Data from 14,432 men´s matches and 14,175 women´s matches of the 2000-2010 World Tour were collected. The variables studied were: match duration, total rallies per set and match, number of sets, team that won the set and match, type of match (equality in score), and gender. The average match duration in beach volleyball is stable, ranging from 30 to 64 minutes, regardless of the number of sets, the stage of the tournament (qualifying round or main draw), or gender. The average number of rallies per match were 78-80 for two-set matches and 94-96 for three-set matches. Matches from the main draw are more balanced than matches from the qualifying round. More balanced matches (smaller point difference between teams) have longer durations. It is not clear why there is no relationship between the number of rallies and match duration. Future studies are needed to clarify this aspect. The results can serve as a reference to guide beach volleyball training (with regard to duration and number of rallies) and to help understand the effect of the rule change.
To determine the effects of a caffeine-containing energy drink on female volleyball players&a... more To determine the effects of a caffeine-containing energy drink on female volleyball players' performance. Thirteen elite female volleyball players ingested 3 mg/kg of caffeine with an energy drink or the same drink without caffeine (placebo drink) in a double-blind and randomized study. Then, participants performed: standing spike, jumping spike, spike jump, blocking jump, squat jump, countermovement jump, manual dynamometry and the agility T-test. A simulated volleyball game was played, videotaped and notated afterwards. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the standing spike (19.2 ± 2.1 vs. 19.7 ± 1.9 m·s; P= 0.023) and in the jumping spike (17.9 ± 2.2 vs. 18.8 ± 2.2 m·s; P= 0.038); and jump height in the squat jump (28.1 ± 3.2 vs. 29.4 ± 3.6 cm; P= 0.028), countermovement jump (32.0 ± 4.6 vs. 33.1 ± 4.5 cm; P= 0.018), spike jump (43.3 ± 4.7 vs. 44.4 ± 5.0 cm; P= 0.025) and block jump (35.2 ± 5.1 vs. 36.1 ± 5.1 cm; P= 0.044). Furthermore, the caffeinated energy drink decreased the time needed to complete the agility T-test (11.1 ± 0.5 vs. 10.9 ± 0.3 s; P= 0.036). During the game, the volleyball actions categorized as successful were more frequent with the caffeinated energy drink (34 ± 9 vs. 45 ± 9%; P< 0.001) while imprecise actions decreased (28 ± 7 vs. 14 ± 9%; P< 0.001) when compared to the placebo drink. Commercially available energy drinks can significantly improve physical performance in female volleyball players. Increased physical performance leaded to improved accuracy during an actual volleyball match.
International Journal of Sports Physiology and Performance, 2014
There are no scientific data about the effects of caffeine intake on volleyball performance. The ... more There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.
Scandinavian Journal of Medicine & Science in Sports, 2017
Article type : Original Article Serum IL-15 and IL-15Rα levels are decreased in lean and obese ph... more Article type : Original Article Serum IL-15 and IL-15Rα levels are decreased in lean and obese physically active humans.
Valadés, D., Palao, J.M. El radar como instrumento de control del entrenamiento RESUMEN El radar ... more Valadés, D., Palao, J.M. El radar como instrumento de control del entrenamiento RESUMEN El radar es un instrumento capaz de medir de forma directa e inmediata la velocidad de los objetos en movimiento en las actividades deportivas. Su empleo permite valorar de forma indirecta la fuerza que el deportista es capaz de transferir al móvil. Su uso no requiere colocar al deportista implementos externos. El presente trabajo muestra los conceptos y protocolos para el empleo del radar como elemento del control indirecto del trabajo de fuerza. Su utilización permitir controlar si las actividades realizadas dentro del entrenamiento son un estímulo adecuado para los deportistas a nivel de aplicación de fuerza. Su uso permitir integrar el trabajo realizado por los preparadores físicos con el trabajo realizado por los entrenadores, evolucionando de situaciones simplificadas a gestos específicos de juego en situaciones reales.
Official Drill Bulletin of the american VOlleyBall cOaches assOciatiOn | VOlume nO. 23, issue nO.... more Official Drill Bulletin of the american VOlleyBall cOaches assOciatiOn | VOlume nO. 23, issue nO. 5 PowerTips march 7, 2012 T he spike is the technical action that achieves the most points in the game . from the mechanical view point, there are three aspects that define spike success : a) hit height, b) ball speed, and c) ball direction. hit height depends on the technical execution of the spike and lower body strength. Ball speed depends on the technical execution of the spike and upper body strength. Ball direction depends on the technical and tactical execution of the spike. the focus of this article is on how to improve and monitor the speed of the spike.
The purpose of this study was to give reference values for serve speed peaks. A retrospective ana... more The purpose of this study was to give reference values for serve speed peaks. A retrospective analysis of the 10-20 fastest serves in men´s and women´s World Tour beach volleyball from the 2005 to the 2012 seasons was done. A total of 136 serves from the men´s competition and 141 serves from the women's competition was included in the study. The results show: 1) for males, the average serve speed peak was 98.3 ± 4.3 km·h-1, and the serve speed peak was 114.0 km·h-1; and 2) for females, the average serve speed peak found was 80.0 ± 2.7 km·h-1 and the serve speed peak was 86.5 km·h-1. No significant differences were found between the first four years and the next four years in the men´s competition, there were significant differences between the first four years and the second four years in the women´s competition. Significant differences were found between men and women in speed serve peaks. The data found can help coaches establish the reference values of serve speed for the pow...
International Journal of Performance Analysis in Sport
The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest time ... more The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest time for women's beach volleyball players in relation to their in-game role. The sample of this study was composed of 2,708 rallies played by 48 female beach volleyball players, which corresponded to 69 sets of the 2008 Olympic Games. The variables recorded were: ball contacts, jumps, hits, work time, rest time, and player's role (defense specialist, blocker, or no specialization). A significantly higher number of jumps were performed by blockers. No differences were found in the number of contacts or hits. The work : rest ratio was 1 : 5. This paper discusses how the data can be used to create game-like situations in practices regarding physical demands in women's beach volleyball.
The objectives of the present study were: a) to assess normative profiles for the serve speed of ... more The objectives of the present study were: a) to assess normative profiles for the serve speed of peak-performance volleyball players in order to guide practice sessions for men´s teams (study 1) and women´s teams (study 2), and b) to establish the possibilities and the ranges of speed that a volleyball throwing machine can offer for working on reception in volleyball (study 3).
The purpose of this paper was to study the ranges in height, weight, age, spike reach, and block ... more The purpose of this paper was to study the ranges in height, weight, age, spike reach, and block reach of volleyball players in relation to the player position and the level of their respective teams in peak performance. The analysed sample included 1454 male and 1452 female players who participated in the volleyball competitions of the Olympic Games and World Championships in the 2000-2012 period. A descriptive, correlational, and longitudinal design was used. The variables studied were: the player position, body height, weight, body mass index, spike reach, block reach, age, and team level. The results show differences between body height, spike and block reaches, and the age of the players by their position. These differences are related to the needs of the different positions with regard to the actions they execute. Middle-blockers, outside-hitters, and opposites have the characteristics that are most suitable for blocking and spiking, and the setters and liberos appear to have characteristics conducive to setting and receiving as well as digging, respectively. The differences found in the studied variables with regard to the playing position are related to players' needs regarding the actions they perform. Player´s age was a variable that differentiated first teams at this level of competition for males, and physical capacities (body height, weight, spike reach, and block reach) were variables that differentiated first teams at this level of competition for females.
The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest ratio... more The purpose of this study was to assess the ball contacts, jumps, hits, work time, and rest ratio in male beach volleyball players in relation to their tactical roles. The sample of this study included 6970 rallies played by 91 beach volleyball players, which corresponded to 179 sets of the 2008 Men's Beach Volleyball World Tour (FIVB). We analyzed: ball contacts, jumps, hits, work time, rest time, set (first, second or third), and player's tactical role (e.g., defense specialist, blocker, or no specialization). A significantly higher number of jumps were executed by blockers. No differences were found in the third set for any of the physical variables studied. This paper provides references about the physical demands (e.g., contacts, jumps, and hits for blockers and defense specialists) and temporal patterns of the beach volleyball game (i.e., work and rest time) for two-set matches and three-set matches.
After the 2000 Olympic Games, the Fédération Internationale de Volleyball (FIVB) modified the sco... more After the 2000 Olympic Games, the Fédération Internationale de Volleyball (FIVB) modified the scoring system used in beach volleyball from side-out to a rally point system. The goal was to facilitate the comprehension of the game and to stabilize match duration. The purpose of this study was to assess the duration and number of rallies in men´s and women´s beach volleyball matches ). Data from 14,432 men´s matches and 14,175 women´s matches of the 2000-2010 World Tour were collected. The variables studied were: match duration, total rallies per set and match, number of sets, team that won the set and match, type of match (equality in score), and gender. The average match duration in beach volleyball is stable, ranging from 30 to 64 minutes, regardless of the number of sets, the stage of the tournament (qualifying round or main draw), or gender. The average number of rallies per match were 78-80 for two-set matches and 94-96 for three-set matches. Matches from the main draw are more balanced than matches from the qualifying round. More balanced matches (smaller point difference between teams) have longer durations. It is not clear why there is no relationship between the number of rallies and match duration. Future studies are needed to clarify this aspect. The results can serve as a reference to guide beach volleyball training (with regard to duration and number of rallies) and to help understand the effect of the rule change.
To determine the effects of a caffeine-containing energy drink on female volleyball players&a... more To determine the effects of a caffeine-containing energy drink on female volleyball players' performance. Thirteen elite female volleyball players ingested 3 mg/kg of caffeine with an energy drink or the same drink without caffeine (placebo drink) in a double-blind and randomized study. Then, participants performed: standing spike, jumping spike, spike jump, blocking jump, squat jump, countermovement jump, manual dynamometry and the agility T-test. A simulated volleyball game was played, videotaped and notated afterwards. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the standing spike (19.2 ± 2.1 vs. 19.7 ± 1.9 m·s; P= 0.023) and in the jumping spike (17.9 ± 2.2 vs. 18.8 ± 2.2 m·s; P= 0.038); and jump height in the squat jump (28.1 ± 3.2 vs. 29.4 ± 3.6 cm; P= 0.028), countermovement jump (32.0 ± 4.6 vs. 33.1 ± 4.5 cm; P= 0.018), spike jump (43.3 ± 4.7 vs. 44.4 ± 5.0 cm; P= 0.025) and block jump (35.2 ± 5.1 vs. 36.1 ± 5.1 cm; P= 0.044). Furthermore, the caffeinated energy drink decreased the time needed to complete the agility T-test (11.1 ± 0.5 vs. 10.9 ± 0.3 s; P= 0.036). During the game, the volleyball actions categorized as successful were more frequent with the caffeinated energy drink (34 ± 9 vs. 45 ± 9%; P< 0.001) while imprecise actions decreased (28 ± 7 vs. 14 ± 9%; P< 0.001) when compared to the placebo drink. Commercially available energy drinks can significantly improve physical performance in female volleyball players. Increased physical performance leaded to improved accuracy during an actual volleyball match.
International Journal of Sports Physiology and Performance, 2014
There are no scientific data about the effects of caffeine intake on volleyball performance. The ... more There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.
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