Ground Reaction Forces, Asymmetries and Performance of Change of Direction Tasks in Youth Elite Female Basketball Players.

The magnitude and direction of inter-limb asymmetries in a change of direction (COD) have increased interest in scientific research in recent years. This present study aimed to investigate the magnitude of asymmetries in an elite youth female basketball sample (n = 18, age = 17.79 ± 0.67 y) and determine its directionality using force platform technology. Participants performed 70° and 180° COD tests analyzing the following variables: time, ground contact time (GCT) and ground reaction forces (GRF) along the anterior-posterior, mediolateral, and vertical axes. Inter-limb asymmetries were evident in both COD tests, with substantial differences observed between limbs (p < 0.01). The asymmetry values ranged from 3.02% to 24.31% in COD 180° and from 1.99% to 21.70% in COD 70°, with anterior-posterior GRF consistently exhibiting the highest asymmetry magnitude. Additionally, the directionality exhibited variability between the tests, indicating poor agreement and suggesting the independent directionality of asymmetries across tasks. Moreover, players required more time to complete the COD 180°, the GCT was noticeably longer for the COD 180° than for the COD 70°, and GRF varied across the axis, suggesting that players adapt uniquely to the specific demands of each task. The utilization of force platforms presents a comprehensive approach to assess asymmetries and COD variables performance variables which are "angle-dependent", which could have important implications for COD screening and effective training interventions.

Effects of Exercise-Induced Neuromuscular Fatigue on Jump Performance and Lower-Limb Asymmetries in Youth Female Team Sport Athletes.

The objective of the present study was to examine the effect of acute neuromuscular fatigue on unilateral jump performance and inter-limb asymmetries. Thirty elite youth female team sport athletes (age: U-14 to U-18) performed the Unilateral Countermovement Jump (UCJ) and the Unilateral Drop Jump (UDJ) (18-cm box) tests before and approximately 10 minutes after the 30-15 intermittent fitness test (30-15 IFT). A paired samples t-test showed significant reductions in UCJ jump height in the right leg after the 30-15 IFT (p = 0.018; d = 0.33), but not in the left leg (p = 0.459; d = 0.48). For the UDJ, significant reductions in jump height were shown in both the right (p < 0.001; d = 0.33) and left (p < 0.001; d = 0.33) legs. In addition, for the reactive strength index (UDJ), significant reductions were seen in the left leg after the 30-15 IFT (p < 0.001; d = 0.31), but not in the right leg (p = 0.948; d < 0.001). Only UCJ inter-limb jump height asymmetries increased significantly post 30-15 IFT (p = 0.033; d = 0.46). In conclusion, the current study indicates that the 30-15 IFT provides a sufficient dose of activity for inducing acute fatigue in elite youth female team sport athletes. Therefore, monitoring jump height in unilateral jump testing is recommended given the tests' sensitivity to detect significant differences in physical performance and inter-limb asymmetries under acutely fatigued conditions in healthy youth female athletes.

Comparación de las variables de rendimiento en las principales ligas europeas de hockey sobre patines / Comparação das variáveis de rendimento nas principais ligas europeias de hóquei em patins / Comparison of performance variables in the main European rink hockey leagues

El presente estudio tuvo como objetivo comparar las variables de rendimiento del hockey patines en los campeonatos nacionales de la máxima categoría masculina en España (OK Liga), Portugal (Primeira Divisao) e Italia (Serie A1). Se analizaron un total de 1.665 partidos disputados entre las temporadas 2018-2019 y 2020-2021, correspondientes a la OK Liga (654), Primeira Divisao (497) y la Serie A1 (514). Se realizaron comparaciones utilizando el análisis de varianza (ANOVA) con post hoc de Bonferroni y la prueba t-Student para comparar las variables según la localización del partido. Los resultados muestran que en España se marcan menos goles por partido, que en Italia se marcan más goles por partido y que en Portugal hay más ejecuciones y goles de penalti y de falta directa, mayor cantidad de faltas y de tarjetas y un mayor porcentaje de goles de pelota parada respecto a los goles totales. En los tres campeonatos las variables de rendimiento asociadas a la victoria fueron favorables a los equipos locales. La comparación de los campeonatos puede permitir a los entrenadores tener un mejor conocimiento de las variables de rendimiento de cada competición y ayudar a las federaciones a conocer que competiciones están mejor asociadas con las variables determinantes del espectáculo deportivo, especialmente los goles, para diseñar propuestas de mejoras en los campeonatos pertinentes. (AU)

The present study aimed to compare the rink hockey performance variables in the top national championships of Spain (OK Liga), Portugal (Primeira Divisao), and Italy (Serie A1). A sample of 1,665 matches corresponding to the OK Liga (654), Primeira Divisao (497), and Serie A1 (514) played between the 2018-2019 and 2020-2021 seasons was analyzed. Comparisons were made using an analysis of the variance (ANOVA) followed by Bonferroni's post hoc multiple comparison test. Additionally, the t-Student test was used to compare each variable according to match location. The results show that in Spain, teams score fewer goals per match and inItaly more goals per match. In Portugal, we observe more set-piece shots, more goals, a higher percentage of goals coming from set-pieces compared to total goals, more fouls, and cards shown. Moreover, the performance variables associated with victory were favourable to the local teams in all three championships. Championship comparison enables coaches to understand better specific and contextual performance variables. Our research could also help governing bodies and federations know what competitions arebetter associated with several key performance indicators and design proposals to improve each championship. (AU)

O presente estudo teve como objetivo comparar as variáveis de rendimento do hóquei em patins nos campeonatos nacionais do escalão masculino mais alto em Espanha (OK Liga), Portugal (Primeira Divisão) e Itália (Série A1). Foram analisados 1.665 jogos disputados entre as épocas 2018-2019 e 2020-2021, correspondendo à OK Liga (654), Primeira Divisão (497) e Série A1 (514). As comparações foram feitas usando a análise de variância post hoc de Bonferroni (ANOVA) e o teste t de Student para comparar as variáveis de acordo com a localização do jogo. Os resultados mostram que em Espanha marcam-se menos golos por jogo e em Italia mais golos per jogo. Em Portugal há mais execuções e golos de grandes penalidades e livres diretos, mais faltas e cartões e uma maior percentagem de golos de bola parada em relação ao total de golos. Nos três campeonatos as variáveis de rendimento associadas à vitória foram favoráveis às equipas locais. A comparação dos campeonatos pode permitir que os treinadores tenham um melhor conhecimento das variáveis de rendimento de cada competição e ajudar as federações a saber quais competições estão mais associadas às variáveis determinantes do espetáculo desportivo, em especial os golos, para traçar propostas de melhora nos aspectos relevantes dos campeonatos. (AU)

Acute effects of jaw clenching while wearing a customized bite-aligning mouthguard on muscle activity and force production during maximal upper body isometric strength.

Background/objectives: The possible mechanisms supporting the relationship between the masticatory and the musculoskeletal systems have been recently investigated. It has been suggested that jaw clenching promotes ergogenic effects on prime movers through the phenomenon of concurrent activation potentiation (CAP). The purpose of this study was to analyse the effects of jaw clenching and jaw clenching while wearing mouthguard (MG) on muscle activity and force output during three upper body isometric strength tests. Methods: Twelve highly trained rink-hockey athletes were recruited for the study. A randomized, repeated measures within study design was carried out to compare the acute effects of three experimental conditions: jaw clenching while wearing MG (MG), jaw clenching without MG (JAW) and non-jaw clenching (NON-JAW). Results: Statistical analyses revealed significant higher force output (p < 0.05) in all tests for MG conditions with respect to NON-JAW. When comparing JAW and NON-JAW conditions an increased peak force was found in handgrip (p = 0.045, d = 0.26) and bench press (p = 0.018, d = 0.43) but not in biceps curl (p = 0.562, d = 0.13). When comparing MG and JAW conditions, no differences were observed in any force output. In terms of muscle activity, significant differences were found in the agonist muscles of the handgrip test for MG with respect to NON-JAW (p = 0.031-0.046, d = 0.25-1.1). Conclusion: This study demonstrated that jaw clenching, with and without MG, may be a good strategy to elicit the CAP phenomenon, which seems to promote ergogenic effects in upper body isometric force production. The non-significant differences observed between JAW and MG suggested that the use of MG doesn't make a difference in enhancing the isometric force production neither the muscle activity in upper body isometric strength.

Analysis of injuries during the 2019 Rink Hockey World Championship.

OBJECTIVES: The purpose of this study is to describe the incidence and characteristics of injuries at the 2019 Rink Hockey World Championship. METHODS: A cross-sectional study was performed among rink hockey athletes from three National Teams (Argentina, Portugal, and Spain). All injuries were reported by the medical staff of each National Team during the preparation period and the competition in the 2019 World Championship (Barcelona, Spain). Injury rate was calculated as the number of injuries per 1000 hours of player-hours of exposure. RESULTS: A total of 91 players (n = 61, 67% male; and n = 30, 33% female) participated in the study: 31 Senior Male (34%), 30 Senior Female (33%), and 30 Under-19 Male (33%). A total of 54 games were played by 9 teams from 3 countries, comprising of 4562 and 4380 hours of total athletic game and training exposure recorded, respectively. Fifty-one injuries (20 injuries with time-loss and 31 medical attention -injuries with no time-loss) were reported. The overall injury incidence rate was 11.2/1000 hours (95% CI, 8.5-14.7). The injury incidence during games (27.5; 95% CI, 11.6-65.2) was higher than the injury incidence during training sessions (3.4; 95% CI, 2-5.7). The incidence rate for game for the entire study period was 8.19 times higher (95% CI, 2.61-21.36) than that for training. The global injury burden was 45.4 days/1000 hours for a total exposure time. Acute was the most frequently documented onset and the non-contact was the most common mechanism. The most frequently reported injuries were head contusion (n = 5, 25%), followed by thigh injuries (n = 3, 15%). CONCLUSIONS: The injury incidence reported in a Rink Hockey international competition was 11.2/1000 hours. The risk of injury was higher during games than during training. Prevention strategies for injuries in these kinds of championships may be worth discussing. The craniofacial injuries were the most frequently reported.

Superimposed vibration on suspended push-ups.

Background: Superimposition of vibration has been proposed in sports training using several devices and methods to enhance muscle activation and strength adaptations. Due to the popularity of suspension training, vibration systems have recently been developed to increase the effects of this training method. The present cross-sectional study aims to examine the effects of superimposing vibration on one of the most popular exercises in strength and conditioning programs: push-ups. Methods: Twenty-eight physically active men and women executed push-ups in three suspended conditions (non-vibration, vibration at 25 Hz, and vibration at 40 Hz). OMNI-Res scale was registered, and surface electromyographic signals were measured for the activity of the right and left external oblique, anterior deltoid, triceps brachii, sternal, and clavicular heads of the pectoralis major. Results: A linear mixed model indicated a significant fixed effect for vibration at 25 Hz and 40 Hz on muscle activity. Suspended push-ups with superimposed vibration (25 Hz and 40 Hz) showed a significant higher activity on left (25 Hz: p = 0.036, d = 0.34; 40 Hz: p = 0.003, d = 0.48) and right external oblique (25 Hz: p = 0.004, d = 0.36; 40 Hz: p = 0.000, d = 0.59), anterior deltoid (25 Hz: p = 0.032, d = 0.44; 40 Hz: p = 0.003, d = 0.64), and global activity (25 Hz: p = 0.000, d = 0.55; 40 Hz: p = 0.000, d = 0.83) compared to non-vibration condition. Moreover, OMNI-Res significant differences were found at 25 Hz (6.04 ± 0.32, p = 0.000 d = 4.03 CI = 3.27, 4.79) and 40 Hz (6.21 ± 0.36 p = 0.00 d = 4.29 CI = 3.49, 5.08) compared to the non-vibration condition (4.75 ± 0.32). Conclusion: Superimposing vibration is a feasible strategy to enhance the muscle activity of suspended push-ups.

Relationship between Performance and Inter-Limb Asymmetries Using Flywheel Resistance Device in Elite Youth Female Basketball Players.

The purposes of this study were to quantify inter-limb asymmetries from unilateral jumps, change of direction (COD) speed, and flywheel resistance skill tests and to examine their relationship with physical performance in a sample of elite youth female basketball players. Eleven female basketball players (age = 17.56 ± 0.60 year; body mass = 75.13 ± 12.37 kg; height = 1.83 ± 0.08 m; BMI = 22.42 ± 2.28; sports experience = 6.31 ± 1.73 year; years post-peak height velocity = 4.79 ± 0.68 year) performed a battery of fitness tests in the post-season consisting of the Single Leg Countermovement Jump in vertical (SLCJ-V), horizontal (SLCJ-H), and lateral (SLCJ-L) directions, 135° and 90° COD tests, and four skills (acceleration step, deceleration step, sidestep, and crossover step) with an flywheel resistance device. The results showed significant differences between the higher performing and lower performing limbs across all tasks (p < 0.05). The mean asymmetry index values ranged from 1.26% (COD 135°) to 11.75% (SLC-V). Inter-limb asymmetries were greatest during the flywheel resistance skills. Spearman's correlations (ρ) for all tests were only significant for inter-limb asymmetries during the sidestep test and reduced performance in SLCJ-L (ρ = −0.61; p = 0.046) and all COD deficits (ρ range = −0.72 to −0.81). The findings of the present study showed that inter-limb asymmetries are task-specific in female youth basketball players and suggest that the use of flywheel devices can be included in the battery of tests to detect inter-limb asymmetry.

Return-to-sport following anterior cruciate ligament reconstruction in team sport athletes. Part II: Progressive framework

In the second part of this evidence- and experience-based guide, we present a progressive framework for return-to-sport following anterior cruciate ligament reconstruction in team sport athletes. This framework guides programs that return athletes to competition at maximum performance while minimizing risk of reinjury. We have built onto a framework typically used in team sports that proposes progress move from general to specific. The progression is accomplished through the use of motor learning principles and attention to hypercomplexity, which characterizes situation sports. The framework focuses on preparing players to withstand repeated high-intensity actions, combining jumps, accelerations, decelerations and changes of direction with dribbling, passing, receiving, shooting and/or reacting to their teammates and opponents while minimizing risk of reinjury.

Higher Vertical Jumping Asymmetries and Lower Physical Performance are Indicators of Increased Injury Incidence in Youth Team-Sport Athletes.

ABSTRACT: Fort-Vanmeerhaeghe, A, Milà-Villarroel, R, Pujol-Marzo, M, Arboix-Alió, J, and Bishop, C. Higher vertical jumping asymmetries and lower physical performance are indicators of increased injury incidence in youth team-sport athletes. J Strength Cond Res 36(8): 2204-2211, 2022-To date, the literature about the association between injury-risk factors and actual injury incidence in young elite team-sports athletes is scarce. The main objective of this study was to examine how modifiable factors may affect injury incidence. Eighty-one young elite team-sports athletes (age: under-14 to under-18) performed the countermovement jump (CMJ), a single leg CMJ (SLCMJ), the one-legged hop test (OLHT), a 30-m sprint test, the V-cut test, a repeated sprint ability, and the 30-15 intermittent fitness test (IFT) during the pre-season period. Interlimb asymmetries were calculated for SLCMJ and OLHT. Injuries were recorded prospectively for the entirety of the 2017-2018 season. Comparison of injury and noninjury data was performed using a two-way analysis of variance (ANOVA). Results of the ANOVA according to injury showed significant differences in CMJ ( p = 0.01), SLCMJ on the lowest performing limb ( p = 0.03), and SLCMJ asymmetry (<0.001). Sex × injury interaction was significant from CMJ ( p = 0.018) and 30-15 IFT ( p = <0.001). In conclusion, this study indicated that athletes with greater interlimb asymmetries, less vertical jump capacity, and lower intermittent aerobic fitness had a greater predisposition to injury. Therefore, monitoring CMJ, aerobic performance, and interlimb asymmetries is recommended given their sensitivity to detect significant differences between injured and healthy youth athletes.

The Influence of Individual Set-Pieces in Elite Rink Hockey Match Outcomes.

The main objective of this study was to analyze the influence of individual set-pieces (Free Direct Hits and Penalties) in elite rink hockey match outcomes in different game situations. A sample of 161 matches played between high-standard teams during ten consecutive seasons (2009-2010 to 2018-2019) were analyzed using a binary logistic regression. The full evaluated model was composed of an explanatory variable (set-pieces scored) and five potential confounding and interaction variables (match location, match level, match importance, extra time, and balanced score). However, the final model only included one significant interaction variable (balanced score). The results showed that scoring more individual set-pieces than the opponent was associated with victory (OR = 6.1; 95% CI: 3.7, 10.0) and was more relevant in unbalanced matches (OR = 19.5; 95% CI: 8.6, 44.3) than in balanced matches (OR = 2.3; 95% CI: 1.2, 4.5). These findings indicate that individual set-pieces are strongly associated with match outcomes in matches played between high-standard teams. Therefore, it is important for teams to excel in this aspect, and it is suggested that these data can encourage coaches to reinforce the systematic practice of individual set-pieces in their training programs. Additionally, it is suggested that teams have specialist players in this kind of action to mainly participate in these specific match moments.

Return-to-sport following anterior cruciate ligament reconstruction in team sport athletes. Part I: From initial injury to return-to-competition / Regreso al deporte después de la reconstrucción del ligamento cruzado anterior en atletas de deportes de equipo. Parte I: De la lesión inicial al regreso a la competencia

There is a high incidence of non-contact anterior cruciate ligament (ACL) injury in team sports, especially among adolescent females. This injury is associated with an increased risk of developing osteoarthritis later in life and a decrease in lifetime physical activity. Traditionally, return-to-sport (RTS) programs following ACL injury have focused on restoring the athlete's general health and tissue healing. We will propose a framework that views RTS as a two-part process: first, recovery of general health after ACL reconstruction (ACL-R) (rehabilitation) and then return to competition (RTC) after ACL-R, all of which occurs on a continuum. The objective of Part I is to stablish the foundation to propose an evidence- and experience-based guide on RTS following ACL reconstruction in athletes participating in team sports, specifically for later phases. First, we describe the causes of and risk factors associated with ACL injury. Next, we describe the specific characteristics of team sports that predispose athletes to ACL injury. Finally, we present a progressive framework to successfully return athletes to a pre-injury level of competition that also minimizes risk of reinjury. In Part II we will focus on how to put the proposed framework into practice when return team sport athletes to play following ACL-R.(AU)

Effects of wearing a customized bite-aligning mouthguard on powerful actions in highly trained swimmers.

BACKGROUND/OBJECTIVES: The potential advantages of wearing customized bite-aligning mouthguards on several performance parameters such as muscular strength, power and reaction time have been reported. Literature shows that the concurrent activation potentiation phenomenon, elicited by a powered and balanced jaw clenching, can provide athletes with several neuromuscular advantages. The aim of the present study was to investigate the acute effects of jaw clenching while wearing a customized bite-aligning mouthguard on swimming start, countermovement jump and swim bench test, in contrast to two other conditions: non-jaw clenching and jaw clenching without mouthguard. METHODS: A randomized, repeated measure within study design was used to compare the condition effect on eight highly trained elite male and female swimmers. RESULTS: Statistical analysis revealed a significant increase in the countermovement jump height (p = 0.041) when comparing the use of mouthguards with the non-jaw condition. In the swim bench, a significant greater time to peak force (p = 0.049) was found when comparing the use of mouthguards with the jaw condition. Although, non-significant effects, small differences were found in the start reaction time and 15-m freestyle swimming when comparing the use of mouthguards with the non-jaw condition. CONCLUSION: This study demonstrated that wearing customized, bite-aligning mouthguards had an ergogenic effect on specific measures of vertical jump and swim bench test, whereas non-meaningful but small differences were found in swimming start.

Detección de déficits neuromusculares a través del análisis del patrón de salto y aterrizaje en deportistas adolescentes / Detecção de déficits neuromusculares por meio da análise do padrão de saltos e aterrissagens em atletas adolescentes / Detection of neuromuscular deficits through jumping pattern analysis in adolescent athletes

El objetivo principal del presente estudio fue analizar el rendimiento de la técnica del salto y aterrizaje en deportistas adolescentes mediante la versión modificada del Tuck Jump Assessment (TJA). Como objetivo secundario se compararon los resultados obtenidos, según sexo. Se puntuó cada variable de la herramienta mediante el análisis en video de la prueba de los 75 participantes incluidos en el estudio. Las variables contempladas fueron la puntuación global del TJA y cada criterio del instrumento: 1) Valgo de la extremidad inferior en el aterrizaje; 2) Muslos no paralelos (punto máximo de salto); 3) Muslos no alineados durante la fase de vuelo; 4) Mala alineación de los pies con los hombros; 5) Posición de los pies no paralela (de la punta al talón); 6) Contacto desigual de los pies (aterrizaje asimétrico); 7) Demasiado ruido en el aterrizaje; 8) Pausa entre saltos; 9) La técnica empeora antes de los 10 segundos; 10) No aterriza en el mismo punto (salto consistente). Los valores promedios de la puntuación global de la versión modificada del TJA fueron 8.85±2.31 en el total de la muestra (8.85±2.63 hombres vs. 8.86±2.14 mujeres). Los resultados de la comparación según sexo indicaron diferencias significativas en el criterio 1 (χ2=10.288; p< 0.01), en el criterio 2 (χ2=20.788; p< 0.01), en el criterio 4 (χ2=22.587; p< 0.01) y en el criterio 10 (χ2=8.883; p< 0.01). En consecuencia, el análisis del patrón de salto y aterrizaje permite identificar alteraciones neuromusculares y biomecánicas del patrón de salto-aterrizaje. (AU)

The main objective of the present study was to analyze the performance of the jump and landing technique in adolescent team sports athletes through the modified version of the Tuck Jump Assessment, (TJA). As a secondary objective, the results obtained werecompared, according to sex. Each outcome measure of the tool was scored through video analysis of the test of the 75 participants included in the study. The main outcome measures were the total score of TJA and each of the ten items: Knee valgus at landing (1), thighs do not reach parallel (2), thighs not equal side-to-side (3), foot placement not shoulder width apart (4), foot placement not parallel (5), foot contact timing not equal (6), excessive landing contact noise (7), pause between jumps (8), technique declines prior to ten seconds (9), and does not land in same footprint (10). The variables contemplated were the global score of the TJA and the ten criteria of the instrument. The average values of the global score of the modified version of the TJA were 8.85±2.31 in the total sample (8.85±2.63 men vs. 8.86±2.14 women). The results of the gender comparison indicated significant differences in item 1(χ2=10.288; p< 0.01), item 2 (χ2=20.788; p<0.01), item 4 (χ2=22.587; p<0.01) and item 10 (χ2=8.883; p< 0.01). Consequently, the analysis of the jump and landing pattern makes it possible to identify neuromuscular and biomechanical alterations of the jump-landing pattern. (AU)

O objetivo principal do presente estúdio fue analisar o rendimiento da técnica do salto e aterrissagem em deportistas adolescentes mediante a versão modificada do Tuck Jump Assessment (TJA). Como objetivo secundário se comparar os resultados obtidos, según sexo. Se puntuó cada variável do herramienta mediante a análise no vídeo da prueba dos 75 participantes incluidos no estudio. As variáveis contempladas na versão global do TJA e cada critério do instrumento: 1) Valgo de la extremidad inferior en el aterrizaje; 2) Muslos no paralelos (ponto máximo de salto); 3) Muslos no alineados durante la fase de vuelo; 4) Mala alineación de los pies con los hombros; 5) Posición de los pies no paralela (de la punta al talón); 6) Contacto desigual de los pies (aterrizaje asimétrico); 7) Demasiado ruido en el aterrizaje; 8) Pausa entre saltos; 9) La técnica empeora antes de los 10 segundos; 10) No aterriza en el mismo punto (salto consistente). Os valores prometidos da versão global modificada do TJA fueron 8.85 ± 2.31 no total da muestra (8.85 ± 2.63 hombres vs. 8.86 ± 2.14 mujeres). Os resultados da comparação segundo sexo indicaron diferencias relevantes no critério 1 (χ2 = 10.288; p<0.01), no critério 2 (χ2 = 20.788; p<0.01), no critério 4 (χ2 = 22.587 ; p <0.01) e o critério 10 (χ2 = 8.883; p<0.01). Na sequência, a análise do patrón de salto y aterrizaje permite identificar alterações neuromusculares y biomecánicas del patrón de salto-aterrizaje. (AU)

sEMG Activity in Superimposed Vibration on Suspended Supine Bridge and Hamstring Curl.

Traditionally in strength and conditioning environments, vibration has been transmitted using platforms, barbells, dumbbells, or cables but not suspension devices. This study aimed to examine the effects on the lower limb of applying superimposed vibration on a suspension device. Twenty-one physically active men and women performed supine bridge and hamstring curl exercises in three suspended conditions (non-vibration, vibration at 25 Hz, and vibration at 40 Hz). In each exercise condition, the perceived exertion scale for resistance exercise (OMNI-Res) was registered, and the electromyographic signal was assessed for gastrocnemius (medialis and lateralis), biceps femoris, semitendinosus, gluteus maximus, and rectus femoris. A linear mixed model indicated a significant fixed effect for vibration at 25 Hz and 40 Hz on muscle activity in suspended supine bridge (p < 0.05), but no effect for suspended hamstring curl (p > 0.05). Likewise, the Friedman test showed a significant main effect for vibration at 25 Hz and 40 Hz in suspended supine bridge (p < 0.05) but not for suspended hamstring curl (p > 0.05) on OMNI-Res. Post hoc analysis for suspended supine bridge with vibration at 25 Hz showed a significant activation increase in gastrocnemius lateralis (p = 0.008), gastrocnemius medialis (p = 0.000), semitendinosus (p = 0.003) activity, and for semitendinosus under 40 Hz condition (p = 0.001) compared to the non-vibration condition. Furthermore, OMNI-Res was significantly higher for the suspended supine bridge at 25 Hz (p = 0.003) and 40 Hz (p = 0.000) than for the non-vibration condition. Superimposed vibration at 25 Hz elicits a higher neuromuscular response during the suspended supine bridge, and the increase in vibration frequency also raises the OMNI-Res value.

Assessing the Magnitude and Direction of Asymmetry in Unilateral Jump and Change of Direction Speed Tasks in Youth Female Team-Sport Athletes.

The direction of inter-limb asymmetries and the change of direction (COD) deficit are two aspects that have increased in recent years. The main objective of the present study was to assess the magnitude of neuromuscular asymmetries in an elite youth female team-sports sample and determine its directionality. Secondary objectives were to evaluate the relationship between COD deficit, linear speed and COD time performance. Elite female youth basketball and handball players (n = 33, age = 16 ± 1.17 y) performed the Single Leg Countermovement Jump in vertical (SLCJ-V), horizontal (SLCJ-H), and lateral (SLCJ-L) directions, the COD and the 10-m sprint. Results showed statistical differences between limbs in all the neuromuscular tests (p < 0.001). The Kappa coefficient showed poor to fair levels of agreement between tasks (K range = -0.087 to 0.233), indicating that asymmetries rarely favoured the same limb between skills. Additionally, small and non-significant correlations were found between the linear sprint capacity and the COD ability. The findings of the present study highlight the independent directionality of asymmetries across tests. The COD deficit does not appear to be much more advantageous than COD total time to measure asymmetry. Practitioners are encouraged to use a fitness testing battery to detect existing side differences and each ability should be specifically trained with functional tasks.

Analysis of the Individual Set-Pieces Influence on the Teams' Ranking in Rink Hockey.

The main objective of this research was to analyze the individual set-pieces influence on the final season ranking in rink hockey. For this purpose, 6,920 individual set-pieces from 1,680 matches corresponding to free direct hits (n = 4,332) and penalty shots (n = 2,588) were analyzed during seven consecutive seasons (2012-13 to 2018-19) in the First Spanish League (Ok Liga). The variables recorded were the following for each team: total points, free direct hits attempted, free direct hits scored, penalties attempted, penalties scored, total goals scored during the season, free direct hits received, goals received from free direct hits, penalties received, goals received from penalties and total goals received in the season. Results showed that 21.08% of the goals were scored by free direct hits and penalty shots (11.58% and 9.49%, respectively). Likewise, teams ranked in a better position achieved higher effectiveness in individual set-pieces and their goalkeepers were more effective in defending the free direct hits and penalties. Furthermore, results showed significant correlations between team season points and better performance in individual set-pieces variables. Therefore, the results of this study demonstrated the importance of systematic practice of free direct hits and penalty shots for teams' success in rink hockey. Additionally, it is suggested that teams possess special players to execute these particular elements of match play.

Seasonal variation of inter-limb jumping asymmetries in youth team-sport athletes.

The main objective of the present study was to provide seasonal variation data for inter-limb asymmetry in youth elite team-sport athletes. Fifty-nine players performed the single-leg countermovement jump (SLCMJ) and the one leg hop for distance (OLHT) tests during pre-season, mid-season and end-season. A repeated-measures analysis of variance was conducted to determine magnitude differences in asymmetry scores between time points. Kappa coefficients (κ) were calculated to determine the levels of agreement for the direction of asymmetry. When comparing inter-limb asymmetry magnitudes across the season, the SLCMJ test showed significantly higher asymmetries at mid-season in comparison with pre-season and end-season (p< 0.01, d= -1.03 for pre to mid; p< 0.01, d= 1.12 for pre to end). However, OLHT inter-limb asymmetry magnitude remained consistent throughout the season (ES range = -0.02 to -0.06). For the direction of asymmetry, levels of agreement ranged from poor to slight in the SLCMJ (k= -0.10 to 0.18) and in the OLHT (k= -0.21 to 0.18). No significant differences were found between mean asymmetry values at any time point or for either test when comparing males and females. In conclusion, jump height asymmetry during the SLCMJ was the only metric to show significant magnitude changes across the season.

Acute Effects of Wearing Bite-Aligning Mouthguards on Muscular Strength, Power, Agility and Quickness in a Trained Population: A Systematic Review.

The purpose of the present systematic review was to determine the acute effects of wearing bite-aligning mouthguards on muscle strength, power, agility and quickness in athletes. A search of the current literature was performed using the electronic databases (until 1 May 2021) Web of Science, Scopus and Medline. The inclusion criteria were: (1) descriptive design studies; (2) with randomized clinical trials; (3) examining the within-subject acute effects of wearing mouthguards on functional and neuromuscular performance parameters; (4) in physical active, recreational or high-standard athletes. Twenty-seven studies met the inclusion criteria. Sixteen reported positive effects in some of the variables assessed, two reported negative effects and the rest found no significant differences. Overall, the main findings described in the literature are inconclusive concerning the neuromuscular advantages of using mouthguards in muscle strength, power, agility and quickness. These discrepancies might be related to several factors such as differences in testing protocols, poor control of the jaw magnitude and improper mouthguard designs. Despite these differences, after conducting the present systematic review, the authors speculate that jaw clenching while wearing custom-made, bite-aligning oral devices might promote beneficial effects in lower limb power actions, especially in jump ability and knee extension movements. Thus, athletes might consider the use of mouthguards, not only for their protective role but also for the potential ergogenic effects in specific actions, mainly those for which lower limb muscular power are required.

Cardioembolic stroke: risk factors, clinical features, and early outcome in 956 consecutive patients

ABSTRACT Background: There is little information about the early clinical features of cardioembolic stroke before complementary examinations. Objective: The aim of this study was to identify risk factors, clinical features, and early outcomes of cardioembolic stroke. Methods: Retrospective study based on prospectively collected data available from a university medical center hospital-based stroke registry. Consecutive patients diagnosed with cardioembolic infarction were selected and compared to those diagnosed with an atherothrombotic stroke. Predictors of cardioembolic infarction were assessed by multivariate analysis. Results: From a cohort of 4597 consecutive patients, we studied 956 patients diagnosed with cardioembolic infarction (80 years [standard deviation (SD) 9.14]; 63% women) and 945 with atherothrombotic infarction (77.01 years [SD 9.75]; 49.8% women). The univariate comparative analysis reported that advanced age (≥ 85 years), female gender, atrial fibrillation (AF), ischemic heart disease, and congestive heart failure were significantly more frequent in the cardioembolic group, whereas hypertension, diabetes, peripheral vascular disease, heavy smoking, hyperlipidemia, and previous transient ischemic attack were significant in the atherothrombotic group. In the logistic regression model, AF (odds ratio [OR] 15.75, 95% confidence interval [CI]: 12.14-20.42), ischemic heart disease (OR 3.12, 95% CI: 2.16-4.5), female gender (OR 1.56, 95% CI: 1.22-2.00), and sudden-onset (OR 1.97, 95% CI: 1.54-2.51), were independent significant predictors of cardioembolic stroke. Conclusions: Potential cardioembolic stroke requires a comprehensive evaluation, since early classification and identification through predictors would improve effective management. (REV INVEST CLIN. 2021;73(1):23-30)

The Behaviour of Home Advantage during the COVID-19 Pandemic in European Rink Hockey Leagues.

The primary purpose of the present study was to compare the home advantage (HA) and the home team performance in the most relevant European rink hockey leagues (Spanish, Portuguese and Italian), considering the presence or absence of spectators in the competition venues due to the effect of COVID-19 restrictions. The sample was composed of 1665 rink hockey matches (654 from the Spanish league, 497 from the Portuguese league, and 514 from the Italian league) played between the 2018-2019 and 2020-2021 seasons. The HA and match variables comparisons were established using several negative binomial regression models. Results showed that the effect of HA did not disappear despite playing without spectators but decreased from 63.99% to 57.41% (p = 0.002). Moreover, the comparison of the match variables showed that playing with spectators benefited local teams' performance, especially in the Portuguese and Italian leagues. Playing with spectators favoured local team performance in rink hockey matches, which is more evident in some analysed leagues. However, as HA does not disappear entirely without spectators, it is necessary to study other relevant performance factors that are not directly or indirectly attributable to crowd behaviour in rink hockey performance analyses.