Effects of Two Different Volume-Equated Weekly Distributed Short-Term Plyometric Training Programs on Futsal Players' Physical Performance

Yanci, J, Castillo, D, Iturricastillo, A, Ayarra, R, and Nakamura, FY. Effects of two different volume-equated weekly distributed short-term plyometric training programs on futsal players' physical performance. J Strength Cond Res 31(7): 1787-1794, 2017-The aim was to analyze the effect of 2 different plyometric training programs (i.e., 1 vs. 2 sessions per week, same total weekly volume) on physical performance in futsal players. Forty-four futsal players were divided into 3 training groups differing in weekly plyometric training load: the 2 days per week plyometric training group (PT2D, n = 15), the 1 day per week plyometric training group (PT1D, n = 12), and the control group (CG, n = 12) which did not perform plyometric training. The results of this study showed that in-season futsal training per se was capable of improving repeat sprint ability (RSA) (effect size [ES] = -0.59 to -1.53). However, while change of direction ability (CODA) was maintained during the training period (ES = 0.00), 15-m sprint (ES = 0.73), and vertical jump (VJ) performance (ES = -0.30 to -1.37) were significantly impaired. By contrast, PT2D and PT1D plyometric training were effective in improving futsal players' 15-m sprint (ES = -0.64 to -1.00), CODA (ES = -1.83 to -5.50), and horizontal jump (ES = 0.33-0.64) performance. Nonetheless, all groups (i.e., PT2D, PT1D, and CG) presented a reduction in VJ performance (ES = -0.04 to -1.37). Regarding RSA performance, PT1D showed a similar improvement compared with CG (ES = -0.65 to -1.53) after the training intervention, whereas PT2D did not show significant change (ES = -0.04 to -0.38). These results may have considerable practical relevance for the optimal design of plyometric training programs for futsal players, given that a 1-day-per-week plyometric training program is more efficient than a 2-day-per-week plyometric training program to improve the futsal players' physical performance.

INFLUENCIA DEL VOLUMEN DE ENTRENAMIENTO PLIOMÉTRICO EN LA CARGA PERCIBIDA DIFERENCIADA DE FUTBOLISTAS DE ALTO NIVEL

Los objetivos del estudio fueron describir la carga percibida diferenciada (dRPE CE) en un equipo de fútbol durante seis semanas de entrenamiento, analizar si existen diferencias en la dRPE CE entre grupos que realizan dos entrenamientos de pliometría con distinto volumen y analizar la evolución a lo largo de las semanas de la dRPE en ambos grupos. Se registró la carga percibida mediante la percepción subjetiva del esfuerzo respiratorio (RPEres) y muscular (RPEmus) de catorce jugadores de fútbol de un equipo de 2.ª División B de la Liga de Fútbol Española, durante seis semanas. Los jugadores fueron divididos en dos grupos, realizando diferentes volúmenes de entrenamiento de fuerza. El primer grupo (G1FX, 24,42 ± 4,35 años, 1,80 ± 0,05 m, 77,32 ± 6,40 kg, 23,81 ± 1,49 kg/m2) realizó un entrenamiento de pliometría en el eje horizontal, y el segundo grupo (G2FX2, 22,43 ± 2,82 años, 1,82 ± 0,07 m, 76,65 ± 7,56 kg, 22,99 ± 1,13 kg/m2) realizó el mismo entrenamiento de fuerza pero con el doble de volumen. Los resultados obtenidos en el presente estudio no mostraron diferencias significativas entre ambos grupos en la dRPE CE en ninguna de las seis semanas registradas y tampoco se obtuvieron diferencias en ninguno de los dos grupos en dicho periodo, ni en el RPEres CE ni en el RPEmus CE. Realizar mayor volumen de entrenamiento de pliometría no implica que los jugadores que más volumen han realizado perciban un mayor RPEres CE ni RPEmus CE.

How does the ball influence the performance of change of direction and sprint tests in para-footballers with brain impairments? Implications for evidence-based classification in CP-Football

The aims of this study were: i) to analyze the reliability and validity of three tests that require sprinting (10 m, 25 m, 40 m), accelerations/decelerations (Stop and Go Test) and change of direction (Illinois Agility Test), with and without ball, in para-footballers with neurological impairments, and ii) to compare the performance in the tests when ball dribbling is required and to explore the practical implications for evidence-based classification in cerebral palsy (CP)-Football. Eighty-two international para-footballers (25.2 ± 6.8 years; 68.7 ± 8.3 kg; 175.3 ± 7.4 cm; 22.5 ± 2.7 kg·m-2), classified according to the International Federation of Cerebral Palsy Football (IFCPF) Classification Rules (classes FT5-FT8), participated in the study. A group of 31 players without CP was also included in the study as a control group. The para-footballers showed good reliability scores in all tests, with and without ball (ICC = 0.53-0.95, SEM = 2.5-9.8%). Nevertheless, the inclusion of the ball influenced testing reproducibility. The low or moderate relationships shown among sprint, acceleration/deceleration and change of direction tests with and without ball also evidenced that they measure different capabilities. Significant differences and large effect sizes (0.53 < ηp2 < 0.97; p < 0.05) were found when para-footballers performed the tests with and without dribbling the ball. Players with moderate neurological impairments (i.e. FT5, FT6, and FT7) had higher coefficients of variation in the trial requiring ball dribbling. For all the tests, we also obtained between-group (FT5-FT8) statistical and large practical differences (ηp2 = 0.35-0.62, large; p < 0.01). The proposed sprint, acceleration/deceleration and change of direction tests with and without ball may be applicable for classification purposes, that is, evaluation of activity limitation from neurological impairments, or decision-making between current CP-Football classes.

Competition Load Described by Objective and Subjective Methods During a Surfing Championship

Fernández-Gamboa, I, Yanci, J, Granados, C, Freemyer, B, and Cámara, J. Competition load described by objective and subjective methods during a surfing championship. J Strength Cond Res 32(5): 1329-1335, 2018-The aims of this study were to describe the competition load of surfers during a single heat through objective and subjective methods and to analyze the relationship between objective and subjective methods with the judges' score. Ten competitive surfers were fitted with a global positioning system (GPS) during a competitive heat. The GPS was synchronized with a chronometer and a stationary video camera to identify the surfer's specific actions. After the end of each heat, participants were assessed for the rating of perceived respiratory and muscular exertion (RPEres, RPEmus), and also, official scores from every participant were collected. A very large significant relationship between wave-riding distance and respiratory perceived exertion heat load (RPEres HL, r = 0.79; ±0.26 confidence limit [CL], p < 0.01, 99.5/0.4/0.1, very likely) was found. Active time was also very large and significantly related to both RPEres HL (r = 0.75; ±0.29 CL, p < 0.05, 99.0/0.8/0.2, very likely) and muscular perceived exertion heat load (RPEmus HL, r = 0.83; ±0.22 CL, p < 0.01, 99.8/0.2/0.0, most likely). Very large significant correlation was obtained between the RPEres and score (r = 0.83; ±0.22 CL, p < 0.01, 99.8/0.2/0.0, most likely). The subjective method seems to be a good instrument to assess the HL of a surf competition. Wave characteristics seem to be an important factor in perceived exertion during competitive surfing.

Effects of the off-Season Period on Field and Assistant Soccer Referees `Physical Performance

The evolution of referees’ physical fitness has been studied over one or several seasons, however, the variation of the physical performance between the end of the competitive season (T1) and the start of the following pre-season (T2) has not been ascertained. Therefore, the aim of this study was to analyze the effects of the transition period on physical performance variables (i.e. linear straight sprint, change of direction ability and endurance) in National Soccer Division referees. Forty-five Spanish referees volunteered to participate in this study. Participants were classified according to competitive status, field referees (FR, n = 23) and assistant referees (AR, n = 22). A loss of performance (p < 0.05) was observed in the 20 and 30 m linear straight sprint between T1 and T2 in both FR (1.64-1.56%, d = 0.29 to 0.32) and AR (2.01-3.41%, d = 0.33 to 0.60). In T2 the FR significantly improved the distance covered (p < 0.05, 13.11%, d = 0.39) in the Yo-Yo Intermittent Recovery test (YYIR1). Besides, significant differences were observed between FR and AR in the distance covered (p < 0.05, −23.55%, d = −0.97) in the YYIR1 test in T2. More research may be necessary to focus on the off-season period in order to implement specific training programs and consequently reduce the loss of sprint ability in field and assistant referees and the decrease in cardiovascular fitness in assistant referees.

The intensity and match load comparison between high spinal cord injury and non-spinal cord injury wheelchair basketball players: a case report

INTRODUCTION

This is a comparative case study between one high spinal cord injury (SCI) and two non-SCI players during an official wheelchair basketball (WB) match. The aim of the study was to calculate the differences in the absolute and relative HR responses and in the match load among one SCI and two non-SCI players in the same WB match.

CASE PRESENTATION

The study was conducted with first-division WB players in Vitoria-Gasteiz, Spain (2014). All of the participants had played the whole official WB match. Absolute heart rate (HR) in the test (10 m Yo-Yo Intermittent Recovery Test Level 1, YYIR1 10 m) as well as absolute and relative HR and match load (ML) were recorded for these three players in an official WB match.

DISCUSSION

The HRpeak and mean during the YYIR1 10 m test and the whole WB match were lower for the SCI player than the non-SCI players. However, as opposed to absolute HR values, relative HR values and ML reported very similar responses among SCI and non-SCI values. Moreover, in the high-intensity HR zone the values were similar among the three players but not in the low (<75% of HRpeak), moderate (75-85% of HRpeak) and maximal (>95% of HRpeak) HR zones. Although the absolute HR values were lower for the SCI player, the relative values and the ML were similar for all the players. Therefore, it could be necessary to use relative HR values to quantify the intensity of efforts in the WB matches.

Monitoring perceived respiratory and muscular exertions and physical fitness in young professional soccer players during a 32-week period

The aim of this study was to examine the association of perceived respiratory and muscular exertions and associated training load (TL) for monitoring changes in several aerobic fitness and neuromuscular performance parameters during 32 weeks of soccer training in young professional players. Twenty male soccer players (age=20.6±1.8 years, body height=1.80±.06 m, body mass=73.6±6.7 kg) belonging to the same reserve team of a Spanish La Liga Club participated in this study. Countermovement jump (CMJ), CMJ with arm swing, linear sprint running (over 5 m and 15 m) and an aerobic fitness running test were performed at the start of the pre-season (Test 1) and 32 weeks later (Test 2). During these eight months, after each training session and match, players rated their perceived exertion (sRPE) separately for respiratory (sRPEres) and leg musculature (sRPEmus) effort. Training load was calculated by multiplying the sRPE value by the duration of each training session or match. Accumulated training and match volume (i.e., time) and associated respiratory and muscular training loads were negatively correlated with the changes in aerobic&nbsp;fitness performance after 32 weeks of training (r=-.53/-.62). In addition, accumulated perceived respiratory load was negatively correlated with the changes in 15 m sprint performance (r=-.51/-.53). A high practice volume (time) and associated respiratory and leg muscular TL can impair the long-term improvement of aerobic fitness and sprint performance in professional soccer players.

Specificity of jumping, acceleration and quick change of direction motor abilities in soccer players

The purpose of this study was to determine the underlying structure of the stretch-shortening cycle (SSC) jumping, acceleration and change-of-direction (COD) abilities in soccer players using principal component factor analysis (PCA). Based on the results of recent studies on male college athletes, we hypothesized that slow SSC jumping, acceleration and COD represent independent motor abilities in soccer players. Forty two soccer players (23.2±2.36 yr) performed three tests for each group of rapid lower-body movements: a) three vertical slow SSC jumping tests ‒ squat jump (SJ), countermovement jump (CMJ) and arm swing countermovement jump (CMJAS), b) three acceleration tests ‒ 5, 10 and 15 meter sprint times (ACC5, ACC10 and ACC15), and c) three COD tests ‒ modified agility test free (MATF), the 505 agility test (505) and 20 yard agility test (Y20). PCA was applied to establish the relationships among the factors (i.e. motor abilities) underlying the included manifest variables (i.e. performance tests). This procedure reduced all variables to a smaller number of independent latent dimensions. The results indicated three separate factors that may correspond to slow SSC jumping, acceleration and COD abilities. The magnitude of the correlation coefficients among the three motor abilities extracted was r&lt;.56. Therefore, it is suggested that slow SSC jumping, acceleration and COD abilities represent independent motor abilities and consequently these should be trained and evaluated separately to assess soccer players’ physical profiles.

Relación entre la capacidad cardiovascular y la capacidad de esprints repetidos en árbitros de fútbol de alto nivel

Los objetivos de este estudio fueron por un lado, describir el rendimiento en una prueba de rendimiento cardiovascular realizada en laboratorio y en otra de esprints repetidos (RSA) en árbitros de fútbol de alto nivel, y por otro lado, analizar la asociación entre los resultados obtenidos en ambas pruebas. Doce árbitros de fútbol de alto nivel (Divisiones 1ª, 2ª y 2ª B, 28,8±5,1 años, 73,2±6,6 kg, 1,8±0,1 m 22,82±1,38 kg·m-2) participaron en el estudio. Los árbitros obtuvieron un consumo máximo de oxígeno (VO2max) de 59,50±4,56ml·kg-1·min-1. El tiempo medio de los esprints repetidos (RSAMedia) en 15 y 30 m fue de 2,54±0,09 s y 4,43±0,14 s, respectivamente, tardando 15,26±0,53 s y 26,60±0,82 s en completar los seis esprints (RSATotal). Los índices de fatiga en 15 y 30 m fueron de 2,25±1,05% y 3,33±1,59% (RSASdec) y de 3,45±2,92% y 6,31±4,63% (RSACambio).Se obtuvieron asociaciones positivas entre distintas variables cardiovasculares y de tiempo en RSA. Por el contrario, el consumo de oxígeno en las intensidades de umbral ventilarorio 1 (VT1) y  umbral ventilatorio 2 (VT2) correlacionó negativamente con el índice de fatiga RSASdec.Una mayor capacidad cardiovascular en árbitros de fútbol, a pesar de poder producir un efecto negativo sobre el tiempo empleado en el RSA, puede minimizar la fatiga durante los esprints repetidos.

Effects of horizontal plyometric training volume on soccer players' performance

The aim of this study was to examine the dose response effect of strength and conditioning programmes, involving horizontally oriented plyometric exercises, on relevant soccer performance variables. Sixteen soccer players were randomly allocated to two 6-week plyometric training groups (G1 and G2) differing by imposed (twice a week) training volume. Post-training G1 (4.13%; d = 0.43) and G2 (2.45%; d = 0.53) moderately improved their horizontal countermovement jump performance. Significant between-group differences (p < 0.01) in the vertical countermovement jump for force production time (T2) were detected post-training. No significant and practical (p > 0.05, d = trivial or small) post-training improvements in sprint, change of direction ability (CODA) and horizontal arm swing countermovement jump were reported in either group. Horizontal plyometric training was effective in promoting improvement in injury prevention variables. Doubling the volume of a horizontal plyometric training protocol was shown to have no additional effect over functional aspects of soccer players' performance.

Relación entre la capacidad de aceleración, cambio de dirección y salto horizontal en atletas jóvenes

El objetivo de este estudio fue analizar la asociación existente entre la capacidad de aceleración en línea recta, la capacidad de cambiar de dirección (CODA) y la capacidad de salto horizontal (SH) en jóvenes atletas. En este estudio participaron un total de 264 jóvenes atletas de entre 8 y 16 años (10,2 ± 2,6 años; 37,5 ± 11,7 kg; 1,4 ± 0,1 m, 17,7 ± 2,4 kg·m-2). Se evaluó la capacidad de aceleración en línea recta en los test de 5 y 15 m, la CODA en el test 505 (505) y en el modified agility test (MAT) y la capacidad de SH con contra movimiento (HCMJ) y manos libres (HCMJAS). La asociación entre la capacidad de aceleración en 5 m y los test de CODA (505: r = 0,54, p < 0,01 y MAT: r = 0,62, p < 0,01) o salto horizontal (HCMJ: r = -0,64, p < 0,01 y HCMJAS: r = -0,67, p > 0,05) fue más consistente que la asociación entre la aceleración en 15 m y los test de CODA o SH. La asociación entre el test MAT y el SH (HCMJ: r = -0,73, p < 0,01 y HCMJAS: r = -0,74, p < 0,01) fue mayor que la relación observada entre el 505 y el HCMJ (r = -0,63, p < 0,01) o el HCMJAS (r = -0,61, p < 0,01). El tipo, la duración y la naturaleza de los test de campo utilizados, condicionan las asociaciones observadas entre las distintas habilidades motoras.

Objective and subjective methods for quantifying training load in wheelchair basketball small-sided games

The aim of the present study was to analyse the training load in wheelchair basketball small-sided games and determine the relationship between heart rate (HR)-based training load and perceived exertion (RPE)-based training load methods among small-sided games bouts. HR-based measurements of training load included Edwards' training load and Stagno's training impulses (TRIMP_MOD) while RPE-based training load measurements included cardiopulmonary (session RPEres) and muscular (session RPEmus) values. Data were collected from 12 wheelchair basketball players during five consecutive weeks. The total load for the small-sided games sessions was 67.5 ± 6.7 and 55.3 ± 12.5 AU in HR-based training load (Edwards' training load and TRIMP_MOD), while the RPE-based training loads were 99.3 ± 26.9 (session RPEres) and 100.8 ± 31.2 AU (session RPEmus). Bout-to-bout analysis identified greater session RPEmus in the third [P < 0.05; effect size (ES) = 0.66, moderate] and fourth bouts (P < 0.05; ES = 0.64, moderate) than in the first bout, but other measures did not differ. Mean correlations indicated a trivial and small relationship among HR-based and RPE-based training loads. It is suggested that HR-based and RPE-based training loads provide different information, but these two methods could be complementary because one method could help us to understand the limitations of the other.

Bilateral and unilateral vertical ground reaction forces and leg asymmetries in soccer players

The purposes of this study were to assess unilateral and bilateral vertical jump performance characteristics, and to compare the vertical ground reaction force characteristics of the impulse and landing phase of a vertical jump between the dominant and non-dominant leg in soccer players. The sample consisted of 20 male soccer players (22.80 ± 2.71 years, 1.88 ± 0.06 m, 76.47 ± 8.80 kg) who competed in the third division of the Spanish football league. Vertical jump performance was determined by testing the impulse and landing phase of a bilateral vertical jump, dominant leg vertical jump and non-dominant leg vertical jump. Significant differences (p < 0.05) between dominant and non-dominant legs were found in counter movement jump (CMJ) flight time (LA = -2.38%, d = 0.33), CMJ flight height (LA = -4.55%, d = 0.33) and CMJ speed take-off (LA = -2.91%, d = 0.42). No significant differences were found between the dominant and non-dominant leg in the F1 and F2 magnitudes during the landing phase, the time from the first contact of the foot with the ground to the production of F1, the time from the second contact of the foot with the ground to the production of F2, and the time to stabilization of the landing phase. Although differences were found between the dominant and non-dominant leg in the impulse phase of the jump, no significant differences were found between dominant and non-dominant legs in the landing phase of vertical jump variables.

Change of direction ability test differentiates higher level and lower level soccer referees

This report examines the agility and level of acceleration capacity of Spanish soccer referees and investigates the possible differences between field referees of different categories. The speed test consisted of 3 maximum acceleration stretches of 15 metres. The change of direction ability (CODA) test used in this study was a modification of the Modified Agility Test (MAT). The study included a sample of 41 Spanish soccer field referees from the Navarre Committee of Soccer Referees divided into two groups: i) the higher level group (G1, n = 20): 2ndA, 2ndB and 3rd division referees from the Spanish National Soccer League (28.43 ± 1.39 years); and ii) the lower level group (G2, n = 21): Navarre Provincial League soccer referees (29.54 ± 1.87 years). Significant differences were found with respect to the CODA between G1 (5.72 ± 0.13 s) and G2 (6.06 ± 0.30 s), while no differences were encountered between groups in acceleration ability. No significant correlations were obtained in G1 between agility and the capacity to accelerate. Significant correlations were found between sprint and agility times in the G2 and in the total group. The results of this study showed that agility can be used as a discriminating factor for differentiating between national and regional field referees; however, no observable differences were found over the 5 and 15 m sprint tests.

Anthropometry and Performance in Wheelchair Basketball

This study investigated whether anthropometric characteristics, generic and specific sprinting, agility, strength, and endurance capacity could differentiate between First-Division and Third-Division wheelchair basketball (WB) players. A First-Division WB team (n = 8; age = 36.05 ± 8.25 years, sitting body height = 91.38 ± 4.24 cm, body mass = 79.80 ± 12.63 kg) and a Third-Division WB team (n = 11; age = 31.10 ± 6.37 years, sitting body height = 85.56 ± 6.48 cm, body mass = 71.18 ± 17.63 kg) participated in the study. Wheelchair sprint, agility, strength, and endurance tests were performed. The First-Division team was faster (8.7%) in 20 m without the ball, more agile (13-22%), stronger (18-33%), covered more distance (20%) in the endurance test, and presented higher values of rate of perceived exertion for the exercise load (48%) than the Third-Division team. Moreover, the individual 20-m sprint time values correlated inversely with the individual strength/power values (from r = -0.54 to -0.77, p ≤ 0.05, n = 19). Wheelchair basketball coaches should structure strength and conditioning training to improve sprint and agility and evaluate players accordingly, so that they can receive appropriate training stimuli to match the physiological demands of their competitive level.

Change of Direction Ability Performance in Cerebral Palsy Football Players According to Functional Profiles

The aims of the present study were to evaluate the validity and reliability of the two different change of direction ability (CODA) tests in elite football players with cerebral palsy (CP) and to analyse the differences in performance of this ability between current functional classes (FT) and controls. The sample consisted of 96 international cerebral palsy football players (FPCP) and 37 football players. Participants were divided into four different groups according to the International Federation of Cerebral Palsy Football (IFCPF) classes and a control group (CG): FT5 (n = 8); FT6 (n = 12); FT7 (n = 62); FT8 (n = 14); and CG (n = 37). The reproducibility of Modified Agility Test (MAT) and Illinois Agility Test (IAT) (ICC = 0.82-0.95, SEM = 2.5-5.8%) showed excellent to good values. In two CODA tests, CG performed faster scores compared with FPCP classes (p < 0.01, d = 1.76-3.26). In IAT, FT8 class comparisons regarding the other classes were: FT5 (p = 0.047, d = 1.05), FT6 (p = 0.055, d = 1.19), and FT7 (p = 0.396, d = 0.56). With regard to MAT, FT8 class was also compared with FT5 (p = 0.006, d = 1.30), FT6 (p = 0.061, d = 0.93), and FT7 (p = 0.033, d = 1.01). No significant differences have been found between FT5, FT6, and FT7 classes. According to these results, IAT and MAT could be useful and reliable and valid tests to analyse CODA in FPCP. Each test (IAT and MAT) could be applied considering the cut point that classifiers need to make a decision about the FT8 class and the other FT classes (FT5, FT6, and FT7).

Rating of muscular and respiratory perceived exertion in professional soccer players

This study investigated, in male professional players: (a) fluctuations in rating of local-muscular (sRPEmus) and central-respiratory (sRPEres) perceived exertion measured after the completion of each training and competitive session, over a 9-week competitive period and (b) the influence of quantitative assessment of different training and competition modes on changes in physical performance. sRPEres, sRPEmus, and heart rate were measured in 21 players in 847 individual training and competitive sessions. Training load was calculated by multiplying sRPEmus or sRPEres by the duration of the training or competition sessions. A test battery (vertical jump, sprint, and endurance running) was performed before and after the studied period. At the end of official matches, average sRPEmus was higher (7.4 ± 0.6; p ≤ 0.05) than sRPEres (6.4 ± 1.3). Significant negative correlations were observed between the values of total training and competition time (r = -0.62; p < 0.01) or total added sRPEmus (r = -0.59; p ≤ 0.05), and vertical jump or sprint running velocity changes, respectively. This suggests that sRPEmus should be considered the main fatigue rating during a soccer match. Training and competition volume may have negative effects on the muscle power performance gains of the legs.

Football match officials do not attain maximal sprinting speed during matches

The aims of this study were, first, to analyse the differences between referees and assistant referees in 20- and 30-metre straight line sprinting test performance and in the maximum speeds registered in football matches; and, second, to analyse the differences between the maximum speeds registered in matches and in the straight line sprinting test. Twenty referees from the Spanish Third Football Division participated in this study. Participants were classified as field referees (FR; n=12, age=30.0±6.7 years; body height=178.1±6.6 cm; body mass=73.7±8.3 kg; BMI=23.2±1.8 kg·m-2) and assistant referees (AR; n=8, age=26.0±7.9 years; body height=177.2±7.3 cm; body mass=75.1±8.8 kg; BMI=23.9±3.1 kg·m-2). The maximum speed of each referee during an official competition match (Vmax match) and during a straight line sprint test (SLST) (Vmax 30 m sprint) was recorded using a global positioning system (GPS). The results show that no significant differences were found between FR and AR in the SLST (p&gt;.05, d=.13-.14). However, large effect sizes were found in the maximum speeds recorded in matches (p&lt;.076, d=.96). Furthermore, the maximum speeds of the FR and AR in the matches were significantly lower than the maximum speeds registered in the 30-m SLST (p&lt;.01, d=2.32-2.51). Bearing in mind that field referees and assistant referees do not achieve the maximum speed registered in a 30-metre sprint test in actual football matches, the performance in such accreditation tests does not reflect the characteristics of actions they perform during matches.

The influence of soccer match play on physiological and physical performance measures in soccer referees and assistant referees

The aim of this study was to quantify the acute impact of soccer match officiating on selected physiological and physical performance measures. Twenty-four officials from the Spanish National 3rd Division participated in this study. External global positioning system and internal (heart rate) load data were collected for each match official during 8 official matches. Pre- and post-matches, the referees were assessed for tympanic temperature, blood lactate, 15- and 30-m sprint speeds and unilateral (dominant and non-dominant legs) and bilateral vertical jump performances. For referees, the acute physiological and physical performance effects of officiating (post-match value minus pre-match value) were large increases in blood lactate (1.7 mmol · l(-1); ±90% confidence limit, 0.9 mmol · l(-1); effect size, ES = 4.35), small increases in 15-m sprint (0.09; ±0.04 s; ES = 0.53) and 30-m sprint speeds (0.14; ±0.08 s; ES = 0.39) and a small increase in non-dominant leg jump performance (2.1; ±1.4 cm; ES = 0.31). For assistant referees, there was a small decrease in tympanic temperature (-0.3°C; ±0.2°C; ES = -0.65) and small increases in blood lactate (0.4; ±0.3 mmol · l(-1); ES = 0.66), 15-m sprint speed (0.06; ±0.04 s; ES = 0.47), 30-m sprint speed (0.11; ±0.16 s; ES = 0.49) and bilateral countermovement jump height (3.4; ±1.5 cm; ES = 0.45). Taken together, these data demonstrate that the physical demands of soccer officiating are sufficient to elicit increases in blood lactate and small decrements in sprint performance and, thereby, provide some evidence for match-related fatigue.

Diferencias entre jugadores de fútbol, baloncesto y tenis de mesa en la capacidad de salto vertical y horizontal

Los objetivos de este estudio fueron analizar las diferencias existentes en la capacidad de salto vertical y horizontal en función del deporte practicado (futbol, baloncesto y tenis de mesa) y determinar si existía algún tipo de relación entre las capacidades de salto horizontal y vertical. 37 deportistas de 16-18 años (16 jugadores de fútbol, 11 de baloncesto y 10 de tenis de mesa) fueron evaluados en la capacidad de salto vertical y horizontal, tanto bilateral como unilateral. No se encontraron diferencias significativas en la capacidad de salto vertical, pero si en la capacidad de salto horizontal, siendo los jugadores de baloncesto los que más saltaban. Se encontró una correlación significativa entre el salto horizontal y vertical a dos piernas (r = 0,724, p < 0,01). A pesar de los resultados obtenidos, son necesarios más estudios donde se analicen las diferencias en la capacidad de salto horizontal entre distintos deportes con el fin de corroborar los resultados obtenidos.

The Functional Classification and Field Test Performance in Wheelchair Basketball Players

Wheelchair basketball players are classified in four classes based on the International Wheelchair Basketball Federation (IWBF) system of competition. Thus, the aim of the study was to ascertain if the IWBF classification, the type of injury and the wheelchair experience were related to different performance field-based tests. Thirteen basketball players undertook anthropometric measurements and performance tests (hand dynamometry, 5 m and 20 m sprints, 5 m and 20 m sprints with a ball, a T-test, a Pick-up test, a modified 10 m Yo-Yo intermittent recovery test, a maximal pass and a medicine ball throw). The IWBF class was correlated (p<0.05) to the hand dynamometry (r= 0.84), the maximal pass (r=0.67) and the medicine ball throw (r= 0.67). Whereas the years of dependence on the wheelchair were correlated to the velocity (p<0.01): 5 m (r= -0.80) and 20 m (r= -0.77) and agility tests (r= -0.77, p<0.01). Also, the 20 m sprint with a ball (r= 0.68) and the T-test (r= -0.57) correlated (p<0.05) with the experience in playing wheelchair basketball. Therefore, in this team the correlations of the performance variables differed when they were related to the disability class, the years of dependence on the wheelchair and the experience in playing wheelchair basketball. These results should be taken into account by the technical staff and coaches of the teams when assessing performance of wheelchair basketball players.

Negative Associations between Perceived Training Load, Volume and Changes in Physical Fitness in Professional Soccer Players

The purpose of this study was to examine the usefulness of the rating of perceived exertion training load for monitoring changes in several aerobic fitness and neuromuscular performance variables during 9 weeks of soccer training in young professional players. Nineteen male soccer players (20.2 ± 1.9 years) belonging to the same reserve team of a Spanish La Liga Club participated in this study. Countermovement jump (CMJ), CMJ arm swing, single leg CMJ, a sprint running test (i.e., 5 m and 15 m times) and an aerobic fitness running test were performed at the start of the pre-season (Test 1) and 9 weeks later (Test 2). During 9 weeks, after each training session and match, players reported their rating of perceived exertion (RPE) separately for respiratory (RPEres) and leg musculature (RPEmus) effort. The training load (TL) was calculated by multiplying the RPE value by the duration in minutes of each training session or match. Accumulated RPEmus, and associated TL, as well as accumulated training volume were negatively correlated with the changes in most physical fitness attributes after 9 weeks of training (r = -0.51 to -0.64). Present results suggest that a high perception of leg muscular effort associated with training sessions and matches, as well as an excessive accumulation of training volume (time), can impair the improvement in several physical fitness variables believed to be relevant for on-field soccer performance. Therefore, the independent assessment of leg muscular effort to quantify TL can be an interesting additional monitoring measure in soccer training. Key pointsThe purpose of this study was to examine the usefulness of the perceived exertion-derived TL for monitoring changes in several aerobic fitness and neuromuscular parameters during 9 weeks of soccer training in young professional players.A high perception of leg muscular effort associated with training and matches, as well as an excessive accumulation of training volume (time), can impair several physical fitness factors believed to be relevant for on-field soccer performance.The independent assessment of muscular effort to quantify TL can be an interesting additional monitoring measure in soccer training.

Relación entre distintos test de campo de condición física en jugadores de fútbol amateur

El objetivo de este estudio fue analizar la relación entre distintos test de campo en jugadores de futbol. 28 jugadores de fútbol amateur fueron evaluados en la capacidad de aceleración en línea recta (5 m y 15 m), cambio de dirección (modified agility test libre, MATF), salto horizontal y vertical con contra movimiento y resistencia aeróbica (versión Level 1 del test Yo-Yo). La asociación encontrada entre la capacidad de aceleración en 15 m y el MATF (r=0,727, p<0,01), fue mayor que la obtenida entre la aceleración en 5 m y el MATF (r=0,559 p<0,01). Se observó una mejor correlación en la aceleración en 15 m que en 5 m con la capacidad tanto del salto vertical como horizontal. Posiblemente el tipo de test pueda condicionar las relaciones obtenidas entre las distintas pruebas de rendimiento. 

Effects of different agility training programs among first-grade elementary school students

The aim of the study was to determine which agility training program (low, moderate or high contextual interference) was more effective in first-grade primary school students to provide reliable information to physical education teachers for designing more effective agility programs. A total of 57 first-grade elementary school students participated in the present study. They were randomized into three groups to compare the effects of three different agility training programs based on contextual interference: low contextual interference (N = 19), moderate contextual interference (N = 19), and high contextual interference (N = 19). Contextual interference refers to the relative amount of interference created when integrating two or more tasks into a particular aspect of a training session. Significant improvements in agility were found in the low (p < 0.01, ES = 1.79) and moderate (p < 0.05, ES = 0.61) contextual interference groups after a 4-week training period. These improvements were higher in the low contextual interference group. The high contextual interference group showed no improvements (p > 0.05, ES = 0.28) after the intervention program. Our results suggested that the low contextual interference program is still more effective than the moderate contextual interference program in this group of primary school students.

Changes in Body Composition and Physical Performance in Wheelchair Basketball Players During a Competitive Season

The present study analyzed the changes in body composition and physical performance in wheelchair basketball (WB) players during one competitive season. Players from a WB team competing in the first division of the Spanish League (n = 8, age: 26.5 ± 2.9 years, body mass: 79.8 ± 12.6 kg, sitting height: 91.4 ± 4.4 cm) participated in this research. The upper limbs showed a decrease in subcutaneous adipose tissue and there was an improvement in physical abilities such as sprinting with the ball (5 and 20 m), handgrip and aerobic capacity. However, the changes in physical fitness concerning sprinting without the ball and agility tests were low. It would be interesting to study the effects of implementing specific programs to improve physical performance in WB and to establish more test sessions to monitor the effects of the programs followed.

Sprint, agility, strength and endurance capacity in wheelchair basketball players

The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm) belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball) agility (T-test and pick-up test) strength (handgrip and maximal pass) and endurance (Yo-Yo 10 m recovery test) were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94). The WB players' results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s) and maximal pass (8.39 ± 1.77 m), players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB.

Correlation between agility and sprinting according to student age

The purposes of the study were to assess sprinting and agility performance characteristics and to determine the relationship between these two motor skills in elementary education students. Sprinting and agility performance were assessed in 176 children (88 boys and 88 girls) divided into three groups: Group 1 (G1, N = 98; 48 boys and 50 girls), from the first year of elementary education; Group 2 (G2, N = 38; 15 boys and 23 girls), from the second year of elementary education; Group 3 (G3, N = 40; 25 boys and 15 girls), from the third year of elementary education. Significant differences (p < 0.001) were found in agility ability among the groups and between G1-G3 and G2-G3 in the 5 and 15 m sprint. Regarding gender of the students of the same age, significant differences (p < 0.001) between boys and girls in group G1 and G2 were obtained in the 5 and 15 m sprint. The correlation between agility and acceleration was significant but moderate (0.3 < r < 0.7) in all groups (G1, G2, and G3), in most cases. When the gender factor was included, the results were heterogeneous. Assessing this correlation according to age and gender produced heterogeneous results. For this reason, we think that both are independent qualities and that age and gender are two factors that influence the correlation results.

Jump landing characteristics in elite soccer players with cerebral palsy

The aim of the present study was to analyse the parameters that characterize the vertical ground reaction force during the landing phase of a jump, and to determine the relationship among these parameters in elite soccer players with cerebral palsy (CP). Thirteen male members of the Spanish national soccer team for people with CP (mean age: 27.1 ± 4.7 years) volunteered for the study. Each participant performed three counter movement jumps. The characteristics of the first peak of the vertical ground reaction force during the landing phase of a jump, which corresponds to the forefoot contact with the ground, were similar to the results obtained in previous studies. However, a higher magnitude of rearfoot contact with the ground (F2) was observed in participants with CP than in participants without CP. Furthermore, a significant correlation between F2 magnitude and the elapsed time until its production (T2) was not observed (r = -0.474 for p = 0.102). This result implies that a landing technique based on a delay in the production of F2 might not be effective to reduce its magnitude, contrary to what has been observed in participants without CP. The absence of a significant correlation between these two parameters in the present study, and the high magnitude of F2, suggest that elite soccer players with CP should use footwear with proper cushioning characteristics.

Effects of different contextual interference training programs on straight sprinting and agility performance of primary school students

The aim of this study was to evaluate the effect of a different degree of contextual interference (CI) training program on the change of direction ability (CODA) itself and on the straight sprinting (SSP) performance (5 m and 15 m) in students in the first year of primary school. It also evaluated which CI training program was more effective. Eighty eight students (6.42 ± 0.38 yr) volunteered as participants for the present study. Participants were randomized into 5 different CI training programs (LCI: low contextual interference, MCI: moderate contextual interference, HCI: high contextual interference, VCI: variable contextual interference, and CG: control group) during a 3 week period. Significant CODA improvements (p < 0.05) in pre-post-test were found in MCI (4.39%, ES 0.41) and VCI (9.37%, ES 1. 12) groups. Furthermore, LCI, MCI and HCI groups ameliorated their SSP performance, both in 5 m (5. 92%, ES 0.81; 6.67%, ES 0.90; 8.05%, ES 1.33 respectively) and 15 m SSP (5.86%, ES 0.76; 6.47%, ES 0.80; 2.47% ES 0.41 respectively). These results suggest that training through games of tag (VCI) was the most effective in improving the CODA and training with moderate contextual interference (MCI) was the only type which induced improvements in both capacities (SSP and CODA). Key PointsWe investigated the CODA and SSP performance of students in the first year of primary school and the influence of 5 different training programs on their CODA and SSP ability.Training through games of tag (VCI) was the most effective in improving the CODATraining with moderate contextual interference (MCI) was the only one which induced improvements in both capacities (SSP and CODA).