The effect of match fatigue in elite badminton players using plantar pressure measurements and the implications to injury mechanisms

[EN] The purpose of this study was to investigate the differences in plantar pressure under the lead and trail foot between two lunge tasks to the net in the dominant (LD) and non-dominant (LND) directions, and to explore how fatigue affects the plantar pressure patterns whilst performing movements before and after a competitive match. Peak and mean pressure were measured with the Biofoot-IBV in-shoe system from five repetitions of each task, with sensors positioned under the calcaneus, midfoot and phalanges on the lead and trail foot. Data were collected pre and immediately post playing an official 1st national league competition match. The study was conducted with a sample of thirteen 1st league badminton players. A 2x2 repeated ANOVA found significant differences between the two tasks and between pre and post match (fatigued state). Players also had different foot pressure distributions for the LD and LND tasks, which indicated a difference in loading strategy. In a fatigued state the plantar pressure shifted to the medial aspect of the midfoot in the trail limb, indicating a reduction in control and a higher injury risk during non-dominant lunge tasks.SIGeneralitat Valenciana ACIF121/2015Universidad Católica de Valencia San Vicente Márti

An exploration of the effect of proprioceptive knee bracing on biomechanics during a badminton lunge to the net, and the implications to injury mechanisms

[EN] The aim of this study was to determine changes in knee biomechanics during badminton lunges due to fatigue, lunge strategy and knee bracing. Kinetic and kinematic data were collected from sixteen experienced right-handed badminton players. Three factor repeated measures ANOVAs (lunge direction – fatigue – brace) were performed with Least Significant Difference pairwise comparisons. In addition, clinical assessments including; Y-balance test, one leg hop distance and ankle dorsiflexion range of motion were performed pre and post fatigue. The knee showed significantly greater flexion during the forehand lunge compared to backhand. In contrast, the internal rotation velocity and the knee extension moment were greater during backhand. Knee angular velocity in the sagittal plane, peak knee moment and range of moment in the coronal plane and stance time showed significantly lower values post fatigue. In addition, the peak knee adduction moment showed significantly lower values in the braced condition in both the fatigued and non-fatigues states, and no significant differences were seen for peak vertical force, loading rate, approach velocity, or in any of the clinical assessment scores. There appears to be greater risk factors when performing a backhand lunge to the net compared to a forehand lunge, and proprioceptive bracing appears to reduce the loading at the knee.SIThis work was supported by Generalitat Valenciana ACIF projects [Grants number ACIF2016/121 and BEFPI 2017/014] and Valencia Catholic University ‘San Vicente Mártir’ pre-competitive grants for research groups

Badminton World Championship stress zones and performance factors: The key to success through log-linear analysis

The main purpose was to analyse the frequency and effectiveness of different kind of shots and players’ footwork performed by single men badminton players on World Championship depending on court zone. 18 matches were randomly selected and evaluated with a total of 1,273 points and 5,710 play actions. The most stressed court zone is Z5 and Z8 (middle zone) followed by Z10 (deep and lateral zone), while the most successful areas are Z8 (left middle zone) and Z10. When analysing footwork depending on distance covered by players, large footwork is performed mostly to Z1 and Z2. Hitting the shuttlecock with no previous movement is the most common situation from Z4 and Z5. When gathering in three court zones, the most stressed one is middle zone with similar values for Net and deep court zone. On the contrary, the most successfully gathered court zone is deep one, followed by middle and Net zones.We gratefully acknowledge the support of Generalitat Valenciana ACIF projects [Grant number 2016/121]; Universidad Católica de Valencia “San Vicente Mártir” project: Estudios en el deporte de élite desde los Mixed Methods (fase II). Análiss del Bádminton; Prevención Lesional (UCV2019/230/001)

Badminton World Championship stress zones and performance factors: The key to success through log-linear analysis

[EN] The main purpose was to analyse the frequency and effectiveness of different kind of shots and players’ footwork performed by single men badminton players on World Championship depending on court zone. 18 matches were randomly selected and evaluated with a total of 1,273 points and 5,710 play actions. The most stressed court zone is Z5 and Z8 (middle zone) followed by Z10 (deep and lateral zone), while the most successful areas are Z8 (left middle zone) and Z10. When analysing footwork depending on distance covered by players, large footwork is performed mostly to Z1 and Z2. Hitting the shuttlecock with no previous movement is the most common situation from Z4 and Z5. When gathering in three court zones, the most stressed one is middle zone with similar values for Net and deep court zone. On the contrary, the most successfully gathered court zone is deep one, followed by middle and Net zones.SIGeneralitat Valenciana ACIF projects [Grant number 2016/121], Universidad Católica de Valencia “San Vicente Mártir” project, Estudios en el deporte de élite desde los Mixed Methods, técnicas de análisis de estudios comparativos [UCV2017/230/002

2015 Badminton World Championship: Singles final men’s vs women’s behaviours

[EN] The purpose of the current study was to identify players’ behaviours and to assess differences between genders at final singles matches of 2015 Badminton World Championship, focusing on time events, shots and court movements. Final men’s (MS) and women’s (WS) singles matches of 2015 Yakarta World Championship were analysed (150 points and 967 actions). Official videos from Badminton World Federation were used to carry out the post-event analysis. Variables analyzed were: ‘timing factors’, type of ‘shots’ and players’ trajectories executed during the match. Descriptive (mean and % of distribution) and comparative analysis between gender and result of events (successful vs. unsuccessful) were carried out. Generally speaking, time-related variables show higher figures in the men’s final than in the women’s. Smash, net and lob shots occur more frequently in the men’s final, whereas clear, drop and drive shots are used more often in the women’s final. The hitting of the shuttlecock without any previous movement redominates over the rest or movements for both genders. In the training field, these findings may be used by coaches in order to improve athletes’ performance. In research field, it could be a new way to obtain information that had not been previously taken into account.SIThis research has been made possible thanks to funding from the Generalitat Valenciana through the scholarship for hiring research personnel in training of VALi+d programme

Players’ On-Court Movements and Contextual Variables in Badminton World Championship

[EN] This study aimed to analyze the elite badminton players’ on-court movements related to contextual variables (game, round, and match status). A total of 18 matches of the Jakarta 2015 World Championship (1,273 points and 5,710 play actions) were examined by univariate and bivariate analyses. Significant differences were found when comparing the players’ on-court movements related to game, round, and match status (p < 0.05). All movements were executed more frequently in game 2, with the exception of diagonal large backward left (DLBL), diagonal short backward left (DSBL), diagonal short backward right (DSBR), and longitudinal short backward (LSB). The results obtained related to the round showed that longitudinal large backward (LLB) was the most frequent footwork in R1/16 and R1/2, diagonal short forward left (DSFL) was the most frequent one for R1/4, and transversal short right (TSR) was the most used movement for the final round. According to match status, no movement (NM) was the most common situation before hitting the shuttlecock at any moment during the match. This study shows how contextual variables modulate the elite players’ on-court movements. This information could be valuable for coaches and players, allowing them to better understand the players’ behavior in a competition, which could be used to design more specific training tasks and prepare match strategies in order to improve the players’ performance in competitions.SIGeneralitat Valenciana ACIF2016/121Universidad Católica de Valencia San Vicente Márti

Players’ on-court movements and contextual variables in Badminton World Championship

This study aimed to analyze the elite badminton players’ on-court movements related to contextual variables (game, round, and match status). A total of 18 matches of the Jakarta 2015 World Championship (1,273 points and 5,710 play actions) were examined by univariate and bivariate analyses. Significant differences were found when comparing the players’ on-court movements related to game, round, and match status (p < 0.05). All movements were executed more frequently in game 2, with the exception of diagonal large backward left (DLBL), diagonal short backward left (DSBL), diagonal short backward right (DSBR), and longitudinal short backward (LSB). The results obtained related to the round showed that longitudinal large backward (LLB) was the most frequent footwork in R1/16 and R1/2, diagonal short forward left (DSFL) was the most frequent one for R1/4, and transversal short right (TSR) was the most used movement for the final round. According to match status, no movement (NM) was the most common situation before hitting the shuttlecock at any moment during the match. This study shows how contextual variables modulate the elite players’ on-court movements. This information could be valuable for coaches and players, allowing them to better understand the players’ behavior in a competition, which could be used to design more specific training tasks and prepare match strategies in order to improve the players’ performance in competitions.We gratefully acknowledge the support of the Generalitat Valenciana ACIF projects (Grant Number 2016/121) and the support of Universidad Católica de Valencia “San Vicente Mártir” project: Estudios en el deporte de élite desde los Mixed Methods (fase II). Análisis del bádminton: Prevención Lesional (UCV2019/230/001).Ciencias de la Actividad Física y del Deport

Quantitative and associative analysis of the badminton lunge and hits at the 2015 Yakarta World Championships

[ES] Los jugadores de bádminton realizan diversos tipos de desplazamientos para golpear el volante y volver al centro de la pista lo antes posible, a esperar la devolución por el jugador contrario. Para ello, necesitan moverse de forma acíclica por la pista, y realizar un excelente trabajo de pies, que les permita un amplio rango de movimientos en todas las direcciones. El objetivo de este trabajo es cuantificar los lunges de bádminton, hacia la red y al fondo de la pista, realizados en el Campeonato del Mundo de bádminton 2015 e identificar los tipos de golpeos asociados a estos desplazamientos. Para ello, mediante la metodología observacional y el uso de la herramienta BOT, se analizaron 18 partidos, llevándose a cabo análisis descriptivos univariados y bivariados por medio del test de independencia chi-cuadrado y un análisis de correspondencias simples. Los resultados muestran que los desplazamientos más comunes fueron el diagonal hacia atrás largo a derecha e izquierda (Z5Z10 y Z8Z1), mientras que los menos realizados fueron el diagonal hacia delante izquierda largo y diagonal atrás derecha corto (Z5Z12 y Z5Z1). En los desplazamientos hacia el fondo de la pista, predominaron los golpes de mano alta, mientras que, en los desplazamientos hacia la zona de la red, los más empleados fueron los golpes de mano baja y aquellos considerados más técnicos. Estas consideraciones pueden ser tenidas en cuenta por los entrenadores y jugadores para realizar una mejor preparación táctica de los encuentros.[EN] Badminton players perform different kind of court movements for hit the shuttlecock and back to court centre as fast as possible and wait for the opponent shot to hit the shuttle back. For that reason, they need to move around the court in acyclic way and perform an excellent footwork that enables them a wide range of movements in every direction. The aim of this work is quantify badminton lunges (to the net and to the deep court zone) performed on Badminton World Championship and identify shots associated to the court movements. For that purpose, 18 matches were analysed using the Badminton Observational Tool (BOT). It was carried out a univariate and bivariate descriptive analysis through chi-square test and simple correspondence analysis. Results show left and right large diagonal backward lunges as the commonest court movements (Z5Z10 and Z8Z1), while left large diagonal forward and right short diagonal backward were the least common court movements (Z5Z12 and Z5Z1). High-hand shots were performed predominately when player plays the shuttle from the deep zone court, while for the net zone court, the most commons shots performed were those which low-hand is needed and the most skilled ones considered. These considerations could be taken into account by coaches and players to perform better tactical training.S

Effect of vibration vs non-vibration foam rolling techniques on flexibility, dynamic balance and perceived joint stability after fatigue

[EN] Foam roller and vibration techniques are currently used to assist in recovery after fatigue. The main purpose of this study was to determine the effects of the use of a foam roller with and without vibration on dynamic balance, ankle dorsiflexion, hamstring and lumbar spine flexibility, and perceived knee and ankle stability after an induced fatigue protocol. 24 healthy recreationally active participants (17 males and 7 females) were recruited to a randomized cross over trial consisting of: no treatment (NT), foam roller treatment (FR) and vibration foam roller treatment (VFR). The assessments included; the Sit & Reach test, Y balance test, and post-treatment perceived knee and ankle stability. Measurements were taken after a standardised warm up (baseline), and repeated following an exercise-induced muscle fatigue protocol consisting of repeated lunges until volitional fatigue. The three treatment conditions were assessed on three separate days in a randomized order. A 3×3 repeated measures ANOVA was used to investigate differences between the three treatments over the three time points, and a one factor repeated measures ANOVA was used to determine any differences between treatments using the Global Rate of Change scale when considering perceived stability. FR and VFR treatment conditions both showed a greater ankle dorsiflexion ROM (p<0.001), greater posteromedial and posterolateral reach distances (p<0.001) and a better knee and ankle perceived stability (p<0.001) when compared to the NT condition. A trend toward significance was observed in the hamstring and lumbar spine flexibility (p=0.074) in both treatment conditions when compared to the NT condition. However, no differences were seen between the FR and VFR treatment conditions. Both foam roller treatment conditions seem to assist in exercise-induced muscle fatigue recovery with improvements in range of motion, balance and perceived stability.SIUniversidad Católica de Valencia San Vicente MártirGeneralitat Valencian

2015 Badminton World Championship: Singles final men’s vs women’s behaviours

The purpose of the current study was to identify players’ behaviours and to assess differences between genders at final singles matches of 2015 Badminton World Championship, focusing on time events, shots and court movements. Final men’s (MS) and women’s (WS) singles matches of 2015 Yakarta World Championship were analysed (150 points and 967 actions). Official videos from Badminton World Federation were used to carry out the post-event analysis. Variables analyzed were: ‘timing factors’, type of ‘shots’ and players’ trajectories executed during the match. Descriptive (mean and % of distribution) and comparative analysis between gender and result of events (successful vs. unsuccessful) were carried out. Generally speaking, time-related variables show higher figures in the men’s final than in the women’s. Smash, net and lob shots occur more frequently in the men’s final, whereas clear, drop and drive shots are used more often in the women’s final. The hitting of the shuttlecock without any previous movement redominates over the rest or movements for both genders. In the training field, these findings may be used by coaches in order to improve athletes’ performance. In research field, it could be a new way to obtain information that had not been previously taken into account.This research has been made possible thanks to funding from the Generalitat Valenciana through the scholarship for hiring research personnel in training of VALi+d programme