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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. 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

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.

Introduction Two of the main modifiable risk factors for suffering an injury in the anterior cruciate ligament are known to be the Hamstring-to-Quadriceps (H/Q) Ratio and neuromuscular fatigue. The main purpose of this research was to study the effect of neuromuscular fatigue on the H/Q Ratio and the maximum isometric strength of the quadriceps and hamstrings in teenage female basketball and handball players. Material and methods This is an experimental, pre-post intervention study with a sample of 19 female basketball players and 11 female handball players (17.02 ± 1.19 yo, 177.8 ± 7.2 cm and 68.6 ± 9.3 kg). To assess muscle strength, a maximum isometric strength test was performed in a 90° hip and 60° knee position. The H/Q Ratio was then calculated. The 30–15 Intermittent Fatigue Test (30–15 IFT) was used to induce fatigue, measured using the Rating of Perceived Exertion (RPE) scale. A descriptive analysis and a Student's t-test were performed to study the differences in the H/Q Ratio, muscle strength and pre-post intervention fatigue. Results Although the H/Q Ratio decreased after the 30–15 IFT, the differences were not statistically significant. Regarding strength values, the right and left quadriceps presented strength reductions of 4.52% and 5.55%, respectively. The reduction in strength was statistically significant (p ≤ 0.05), especially in the right hamstring (7.3%) and in the left hamstring (7.5%). The study conclusions suggest that leg muscular strength decreases after a fatigue test and that there is a tendency for the H/Q Ratio to decrease also.

Font-Llado, R, Lopez-Ros, V, Montalvo, AM, Sinclair, G, Prats Puig, A, and Fort-Vanmeerhaeghe, A. A pedagogical approach to integrative neuromuscular training to improve motor competence in children: a RCT. J Strength Cond Res 34(11): 3078-3085, 2020-To assess the effectiveness of a pedagogical approach to an integrative neuromuscular training (INT) program as a warm-up in physical education (PE) lessons in healthy children: (a) to improve the level of motor competence (MC) and (b) to master fundamental motor skills (FMS) patterns, considering the baseline MC level and the time spent when performing different motor tasks. One hundred ninety students (7.43 ± 0.32 years; 52% girls) were included in this randomized controlled trail and grouped up according to MC basal levels (L1-L4). Motor competence and FMS patterns (CAMSA protocol) were assessed before and after the intervention in a group-based INT warm-up (n = 97) and a group-based conventional warm-up (n = 93). The INT program improved MC (p < 0.001; d = 0.71) and FMS (p < 0.001, d = 0.52). The independent predictors of MC change were: baseline MC level (β = -196; p < 0.012), time spent to perform the task (β = -0.235 p < 0.003), and participation in the INT program (β = 0.201; p < 0.005), explaining 71% of its variability. The INT warm-up shows correlations between improvements in MC in relation to time reduction (L1 p = 0.016, d, L2 p = 0.001, and L4 = 0.001) and FMS patterns (L1 p < 0.001, L2 p < 0.003, L3 p < 0.005, and L4 < 0.001) Moreover, only L3, it showed correlation between changes in time and FMS mastery (p = 0.001). Our results showed that a pedagogical approach to an INT program developed as a warm-up in primary school PE lessons can improve MC and FMS patterns in all subjects, independent of the initial MC level. More interestingly, only in L3, the improvement in MC can be explained by the balance in time required to perform the task and the level of improvement in FMS patterns.

Madruga-Parera, M, Bishop, C, Fort-Vanmeerhaeghe, A, Beltran-Valls, MR, Gonzalo-Skok, O, and Romero-Rodriguez, D. Interlimb asymmetries in youth tennis players: relationships with performance. J Strength Cond Res 34(10): 2815-2823, 2020-Change of direction speed (CODS) has been highlighted as a critical component of tennis. Interlimb asymmetries have been commonly studied in jump tests, but less attention given to the topic during CODS. The aim of this study was to quantify interlimb asymmetries in jumping and CODS (during traditional and isoinertial tests) and establish their relationship with measures of physical performance. Twenty-two elite youth tennis players (16.3 ± 1.4 years) performed single-leg countermovement jump (SLCMJ), single-leg broad jump, and single-leg lateral jump, a double 180° turn CODS test, and shuffle lateral step and crossover step with an isoinertial resistance device. Paired-samples t-tests revealed significant differences between limbs for all tests (p < 0.05). Interlimb asymmetry scores ranged from 1.83 to 15.03%, and a 1-way repeated-measures analysis of variance showed significant differences between interlimb asymmetry scores across multiple tests (p < 0.05). Spearman's rank order r correlations showed significant negative relationships between CODS asymmetry and SLCMJ performance on both limbs (r = -0.50; p = 0.02 and r = -0.53; p = 0.01) and CODS performance on both limbs (r = 0.50; p = 0.02 and r = 0.63; p = 0.002). These results show the test-specific nature of asymmetries in youth tennis athletes, with the SLCMJ presenting the greatest magnitude of asymmetry. Furthermore, interlimb differences during CODS were associated with reduced performance during jumping and CODS tests, suggesting the monitoring of asymmetries within this population may therefore be warranted.

Madruga-Parera, M, Bishop, C, Fort-Vanmeerhaeghe, A, Beato, M, Gonzalo-Skok, O, and Romero-Rodriguez, D. Effects of 8-weeks of Isoinertial vs. Cable-resistance Training on Motor Skills Performance and Interlimb Asymmetries. J Strength Cond Res XX(X): 000–000, 2020—The aim of this study was to compare the effects of 8 weeks of isoinertial vs. cable-resistance training on motor skills performance and interlimb asymmetries in handball players. Thirty-four young male handball players (mean ± SD: age: 15.96 ± 1.39 years; height: 1.74 ± 0.73 m; body mass: 70.5 ± 13.3 kg) participated in a randomized trial. The players performed an isoinertial program using a portable flywheel device or a cable-resistance device. Performance variations and interlimb asymmetries in dominant (D) and nondominant (ND) limb means of the unilateral countermovement jump (UCMJ), the unilateral lateral jump (ULJ), the unilateral broad jump (UBJ), handball throwing (HT), change of direction speed (COD180), the linear sprint (S20), the V-CUT test, and the repeated change of direction (RCOD) were recorded. Significant interactions were shown in RCODD (p = 0.003, ηp = 0.25), HT (p = 0.015, ηp = 0.17) and UCMJASY (p = 0.037, ηp = 0.13). Post-hoc testing revealed higher effect sizes in the isoinertial group (p < 0.05) for the performance improvements in RCODD (−1.35 large vs. −0.22, small) and HT (0.88, moderate vs. 0.00, trivial), in addition to interlimb asymmetry reductions in UCMJASY (−0.70 moderate vs. −0.32, small). Significant main effects of time in COD180, RCOD, UCMJ, and UBJ for both limbs (p < 0.05, from moderate to large effect size), and in ULJND (p < 0.001, large), UCMJASY (p < 0.001, moderate), V-CUT (p = 0.014, small), and HT (p = 0.015, large) were found. The effect sizes revealed greater magnitudes in the isoinertial group. In conclusion, although both resistance training programs improve players' to physical performance and reduce interlimb asymmetries, greater improvements were recorded with the isoinertial resistance training than with the cable-resistance methodology.

Background Eccentric hamstring strength seems important in reducing the odds of future hamstring injuries. While age and previous injury are well-known risk factors for future hamstring injuries, the association of age and previous hamstring injury with eccentric hamstring strength in the following season is unknown. Purpose To investigate the association of age and previous hamstring injury with preseason eccentric hamstring strength in soccer players, and to investigate the association between previous hamstring injury duration and preseason eccentric hamstring strength. Study design Descriptive, cross-sectional study. Methods A convenience sample of 284 male amateur soccer players (age 18-38 years) was included in the analyses. Self-reported information about previous season hamstring injury and its duration (three weeks or less; more than three weeks) was collected. Preseason eccentric hamstring strength was obtained during the Nordic hamstring exercise using a field-based device. Results Age had a negative association with preseason eccentric hamstring strength with 0.9% reduction per year. Players with a previous hamstring injury duration of more than three weeks (n=27) had 13% lower preseason eccentric hamstring strength compared to players without previous hamstring injury. Conclusion Older players have lower preseason eccentric hamstring strength than younger players. Players with a previous hamstring injury duration of more than three weeks have lower preseason eccentric hamstring strength than the rest of the players. These results highlight the need to monitor and address the identified weaknesses in eccentric hamstring strength in amateur soccer players, with specific emphasis on older players with a previous hamstring injury of longer duration. Level of evidence 2b.

Context: Understanding how neuromuscular and biomechanical deficits that are associated with knee injuries change as youth mature may improve injury prevention strategies in this population. Objective: To investigate sex and maturation differences in jump-landing technique performance in youths using a practical clinical tool. Design: Cross-sectional study. Setting: High Performance Center Laboratory. Participants: A total of 165 youth athletes were included in this study. Main Outcome Measures: The main outcome measures were each of the 10 items of the modified tuck jump assessment and the total score. These measures include (1) knee valgus at landing, (2) thighs do not reach parallel, (3) thighs not equal side to side, (4) foot placement not shoulder width apart, (5) foot placement not parallel, (6) foot contact timing not equal, (7) excessive landing contact noise, (8) pause between jumps, (9) technique declines prior to 10 seconds, and (10) does not land in same footprint. Results: Only knee valgus at landing had a significant sex × maturation interaction. The main effect of maturation was significant for items 2, 3, 6, 7, 9, and total score. Plyometric technique performance improved with increasing maturation. The main effect of sex was significant for items 1 and 9, with males performing better than females. Conclusions: Female athletes demonstrate increased knee valgus at landing and fatigue relative to males during jump-landing performance. Overall, there was a trend of improved jump-landing performance with maturation.

The magnitude of inter-limb asymmetries has been reported in several studies in different team sports but only some of them have analysed their effects on sports performance. The main purpose of this cross-sectional study was to determine inter-limb asymmetries and examine their relationship with different physical performance tests in rink hockey players. Nineteen rink hockey players (age: 23.37 &plusmn, 4.82 years, body height: 1.75 &plusmn, 0.06 cm, body mass: 73.16 &plusmn, 9.87 kg) performed a mid-season battery of fitness tests consisting of 30 m sprint, countermovement jump (CMJ), and half back squat. Inter-limb asymmetries were assessed using the single leg vertical countermovement jump test (SLCJ-V), single leg horizontal countermovement jump test (SLCJ-H), and 180&deg, change of direction test (COD). Results show a significant relationship between asymmetry in the SLCJ-H test, 30 m sprint (r = 0.63, p &lt, 0.01) and CMJ performances (r = &minus, 0.52, p &lt, 0.05). Additionally, asymmetry in the SLCJ-V showed a significant relationship with CMJ performance (r = &minus, 0.46, p &lt, 0.05). These findings suggest that training programs should aim to reduce the inter-limb asymmetries in rink hockey players to improve their performance. Practitioners and coaches can use this information to assess the potential impact of asymmetries on physical performance in rink hockey players.

The aims of this study were to investigate changes in selected performance measures during an off-season period, their association, and the potential role of age and previous hamstring injury in semi-professional and amateur football players. Seventy-four male players (age: 25 ± 4 years, stature: 178.0 ± 6.6 cm, body mass: 74.9 ± 8.1 kg) were assessed at the beginning and end of the off-season summer-period for sprint, change-of-direction performance and eccentric hamstring strength. Small to medium increases in sprint times were observed at 5 (d = 0.26, p = 0.057), 10 (d = 0.42, p < 0.001) and 30 m (d = 0.64, p < 0.001). Small (d = −0.23, p = 0.033) improvements were observed for COD performance, and no changes in eccentric hamstring strength (d = 0.10, p = 0.317). The changes in the outcomes were not affected by age (p = 0.449 to 0.928) or previous hamstring injury (p = 0.109 to 0.995). The impaired sprint performance was not related to changes in eccentric hamstring strength (r = −0.21 to 0.03, p = 0.213 to 0.856), instead, changes in COD performance were associated with changes in eccentric hamstring strength (r = −0.42, p = 0.008).

This study aimed to understand the acute responses on the muscular activity of primary movers during the execution of a half-squat under different unstable devices. Fourteen male and female high-standard track and field athletes were voluntarily recruited. A repeated measures design was used to establish the differences between muscle activity of the primary movers, the body centre of mass acceleration and the OMNI-Perceived Exertion Scale for Resistance Exercise (OMNI-Res) in a half-squat under four different stability conditions (floor, foam, BOSU-up and BOSU-down). A significant correlation was found between the highest performance limb muscle activity and body centre of mass acceleration for half-squat floor (r = 0.446, p = 0.003), foam (r = 0.322, p = 0.038), BOSU-up (r = 0.500, p = 0.001), and BOSU-down (r = 0.495, p = 0.001) exercises. For the exercise condition, the half-squat BOSU-up and BOSU-down significantly increased the muscle activity compared to half-squat floor (vastus medialis: p = 0.020, d = 0.56, vastus lateralis: p = 0.006, d = 0.75, biceps femoris: p = 0.000&ndash, 0.006, d = 1.23&ndash, 1.00) and half-squat foam (vastus medialis: p = 0.005&ndash, 0.006, d = 0.60&ndash, 1.00, vastus lateralis: p = 0.014, d = 0.67, biceps femoris: p = 0.002, d = 1.00) activities. This study contributes to improving the understanding of instability training, providing data about the acute muscular responses that an athlete experiences under varied stability conditions. The perturbation offered by the two BOSU conditions was revealed as the most demanding for the sample of athletes, followed by foam and floor executions.

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.

Objectives The aim of this study was to quantify and analyze the presence and type of self-acknowledged limitations (SALs) in a sample of manual therapy (MT) randomized controlled trials. Study Design and Setting We randomly selected 120 MT trials. We extracted data related to SALs from the original reports and classified them into 12 categories. After data extraction, specific limitations within each category were identified. A descriptive analysis was performed using frequencies and percentages for qualitative variables. Results The number of SALs per trial article ranged from 0 to 8, and more than two-thirds of trials acknowledged at least two different limitations. Despite its small proportion, 9% of trials did not report SALs. The most common limitation declared, in almost half of our sample, related to sample size (47.5%) followed by limitations related to study length and follow-up (33.3%) and inadequate controls (32.5%). Conclusion Our results indicate that at least two different limitations are consistently acknowledged in MT trial reports, the most common being those related to sample size, study length, follow-up, and inadequate controls. Analysis of the reasons behind the SALs gives some insights about the main difficulties in conducting research in this field and may help develop strategies to improve future research.

Actually, there is scarce literature looking for the relationship between inter-limb asymmetries and performance in youth elite team sports. The main purpose of this cross-sectional study was to examine the relationships between inter-limb asymmetries and physical performance in youth elite team-sports players. A secondary objective was to evaluate the presence of between-sexes differences in inter-limb asymmetries in elite youth team sports players. Eighty-one young elite team-sports athletes (age: u-14 to u-18) performed the star excursion balance test in the anterior direction (SEBT ANT), a single leg vertical countermovement jump test (SLCMJ), the one leg hop test for distance (OLHT), a 30 m sprint test, and the V-cut test. Inter-limb asymmetries were calculated for SEBT ANT, SLCMJ and OLHT. Pearson r was used to analyse the relationships between inter-limb asymmetries and physical performance. Results showed significant (p < 0.05) but small (r = 0.26) relationships between SLCMJ asymmetries and 30 m sprint time for the total group. Significant negative correlations with small to moderate magnitude of correlation were also found between SLCMJ asymmetries and SLCMJ performance on the lowest performing limb for the total group (p < 0.05; r = -0.26), males (p < 0.01; r = -0.48) and females (p < 0.05; r = -0.30). Moreover, significant negative correlations with moderate and large magnitude were also present between OLHT asymmetries and OLHT performance on the lowest performing limb for the total group (p < 0.01; r = -0.44), males (p < 0.01; r = -0.56) and females (p < 0.01; r = -0.64). No correlations were observed between asymmetries and either the V-cut test or SEBT ANT performance. No correlation were observed between SEBT ANT asymmetries and physical performance. In addition, when comparing asymmetry values between sexes there were no significant differences in vertical (p = 0.06) and horizontal (p = 0.61) jumping tests. However, there were significant differences in asymmetry between sexes in the ANT SEBT (p = 0.04). In conclusion, the current study indicated that jumping asymmetries were associated with decrements in sprint speed and jumping performance. Therefore, assessing inter-limb asymmetries would be recommended to improve training interventions for youth elite team-sports athletes.

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.

El objetivo de este trabajo fue comparar y cuantificar las asimetrías neuromusculares entre las extremidades inferiores que presentan los jugadores de hockey sobre patines. Un objetivo secundario fue correlacionar el índice de asimetrías (ASI) entre las diferentes pruebas neuromusculares testadas. Un total de 27 jugadores de sexo masculino de hockey sobre patines (edad = 20,59 ± 3,81 años) realizaron diferentes pruebas neuromusculares de forma unilateral: 1) Test de salto vertical con contra-movimiento (SLCJ), 2) Batería de saltos horizontales (Hop test: single, triple y crossover hop test) y 3) Prueba de velocidad con cambio de dirección (COD test). Se observaron diferencias significativas (p 10% en el test de SLCJ, situación considerada como posible factor de riesgo de lesión. Solamente se obtuvo una correlación significativa entre el SLCJ y el COD test. En consecuencia, y con el objetivo de identificar las asimetrías entre miembros inferiores, es importante considerar la valoración de las diferencias capacidades neuromusculares. Abstract The aim of the current study was to compare and quantify the neuromuscular lower limb asymmetries present in roller hockey players and its link to high risk of injury. A secondary purpose was to correlate the index of asymmetries (ASI) between the different neuromuscular tests performed. 27 male roller hockey players (age = 20.59 ± 3.81 years) performed the single leg countermovement jump (SLCJ), the Hop Test battery (single hop test, triple hop test and crossover hop test) and the change of direction test (COD test). Significant differences were observed (p 10% in the SLCJ, a situation considered as an injury risk factor. Only a significant correlation was obtained between the SLCJ and the COD test. Consequently, it is suggested that the complete neuromuscular profile between lower limbs be evaluated with the different tests, for both in the conditioning programs and in the injury prevention and return-to- play.

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.

Introduction Monitoring load has been a key point in team sports during last years. This study aimed to determine the relationship between the external and internal training load during full basketball practices in elite female youth basketball players. Material and methods Thirteen elite female youth basketball players (age 16.3±1 years, height 181.7±5.8cm and body mass 71.2±9.6kg) had physical and physiological monitored over seven weeks. Players’ internal load was assessed using the session-rating of perceived exertion (sRPE), the Edward's summated heart rate zones model (SHRZ) and, the Banister's training impulse (TRIMPB). The external load was determined through: 1) total accelerations (TA); the sum of all accelerations and decelerations; 2) maximal accelerations and decelerations (TAMax); 3) total accelerations per minutes (TA·min−1); 4) accelerations per minute (Acc·min−1); and 5) decelerations per minute (Dec·min−1). Heart rate-based and accelerometry models were assessed via Polar Pro technology. Results Correlations between variables revealed different magnitudes. SHRZ model showed a positive correlation with TA (0.63); the TRIMPB model showed a high degree of correlation with TA (0.78); the sRPE model also presented a high correlation with TA (0.62). Conclusion Our study establishes different levels of association between external and internal load models in elite female youth basketball players. However, we cannot assume that a high relationship between internal and external loads exists, as both models should be considered as different constructs.

Madruga-Parera, M, Bishop, C, Beato, M, Fort-Vanmeerhaeghe, A, Gonzalo-Skok, O, and Romero-Rodriguez, D. Relationship between inter-limb asymmetries and speed and change of direction speed in youth handball players. J Strength Cond Res XX(X): 000-000, 2019-The aims of the present study were to quantify interlimb asymmetry from jumping, change of direction speed (CODS), and iso-inertial tests and to establish the association between those asymmetry scores and performance during speed and CODS tests in youth handball athletes. Twenty-six youth handball players (age: 16.2 ± 0.9 years) volunteered to participate in this study and performed single-leg countermovement jumps, single-leg broad jumps, single-leg lateral jumps, CODS tests at 180° (CODS180) and 90° (CODS90), change of direction actions with iso-inertial overload (crossover step [CRO] and lateral shuffle step), and a 20-m sprint test. Excellent intraclass correlation coefficient (ICC) values were found for all tests (ICC = 0.96-1.00) with the exception of the dominant limb during the CODS90 test (ICC = 0.69). Interlimb asymmetry scores ranged from 3.66 to 12.67%. Iso-inertial asymmetry values were higher than those found during jumping tasks (9.8-12.7% vs. 3.66-8.76%). Spearman's r correlations showed significant relationships between CRO asymmetry and CODS90 performance on both limbs (r = 0.48-0.51; p < 0.05) and CODS180 (r = 0.41-0.51; p < 0.05) and a sprint test (r = 0.46; p < 0.05). These results show the test-specific nature of asymmetries in youth handball players, with iso-inertial device and CODS deficit presenting the greatest magnitude of asymmetries. Furthermore, interlimb differences during iso-inertial device (CRO) were associated with reduced CODS and sprint performance. These results suggest that the use of iso-inertial devices for the detection of interlimb asymmetry may be more effective than the total time during traditional CODS tests and that larger imbalances are associated with reduced athletic performance in youth handball players.

Objective The aim of this review was to evaluate a selection of major reporting aspects in manual therapy (MT) trials, before and after the publication of the CONSORT extension for nonpharmacological trials (CONSORTnpt) Study Design and Setting We randomly selected 100 MT trials published between 2000 and 2015 and divided them into a pre-CONSORTnpt (n = 50) and a post-CONSORTnpt (n = 50) group. We extracted data on relevant issues of internal validity, reliability, and description of interventions. Two authors extracted data independently. Percentages were used for descriptive analyses, and Fisher’s exact test and the chi-square test were used for group comparisons. Results Six different types of MT interventions with up to 20 controls were analyzed. The most common populations/conditions studied were healthy subjects and subjects with lower back or neck pain. Over 70% of studies included multi-session interventions, and 42% of studies reported long-term followup. The only significant differences between groups were the inclusion of a flowchart diagram, the estimated effect size, precision descriptions, and the description of intervention procedures. Conclusion Our findings suggest that trials in MT show poor reporting even after the availability of standardized guidelines.

Neuromuscular asymmetries have been previously associated with reduced performance. Similarly, maturation has shown that youth athletes may experience a loss of motor control, which could also lead to compromised physical performance. The present study aimed to evaluate and quantify the level of asymmetry among chronological and maturational groups. Forty-one youth tennis players performed the single leg countermovement jump (SLCMJ), star excursion balance test (SEBT) and a change of direction speed (CODS) test. Differences were found between the strongest and weakest limbs across all tests (p &lt, 0.001), and also for SEBT in the posteromedial direction (p = 0.02), SEBT composite score (p &lt, 0.01) in maturation groups, and for SEBT posterolateral direction (p = 0.03) and SEBT composite score (p = 0.01) in chronological groups. The SLCMJ showed the largest inter-limb asymmetries for the circa peak height velocity (PHV) group (19.31 &plusmn, 12.19%) and under-14 (U14) group (17.55 &plusmn, 9.90%). Chronological and maturation groups followed similar trends for inter-limb asymmetries, but the biological index showed larger asymmetry scores in the jumping test at PHV compared to that found in the chronological group (U14). These results show that inter-limb differences may be heightened during PHV. Practitioners can use this information to inform the decision-making process when prescribing training interventions in youth tennis players.

THE SECOND PART OF THIS REVIEW PROVIDES A FLEXIBLE APPROACH TO INTEGRATIVE NEUROMUSCULAR TRAINING (INT) WITH THE GOALS TO IMPROVE INJURY RESILIENCE AND TO ENHANCE SPORT AND MOTOR PERFORMANCE ABILITIES IN YOUTH POPULATIONS. THE PROPOSED MODEL OF INT IN THIS MANUSCRIPT PRESENTS 6 ESSENTIAL COM

Article published in Strength and Conditioning Journal on 01 June 2016 (online), available at: https://doi.org/10.1519/SSC.0000000000000229.

Suspension training is an adjunct to traditional strength and conditioning. The effect of added instability on muscle activation during traditional exercises is unclear and depends on the exercise and type of instability. The purpose of this review was to compare the activations of different muscles in suspension training exercises and their traditional counterparts. A search of the current literature was performed without language restrictions using the electronic databases PubMed (1969-12 January 2017), SPORTDiscus (1969-12 January 2017) and Scopus (1969-12 January 2017). The inclusion criteria were: (1) descriptive studies; (2) physically active participants; and (3) studies that analysed muscle activation using normalised electromyographic signals during different suspension training exercises. Eighteen studies met the inclusion criteria. For the push-up, inverted row, prone bridge and hamstring curl in suspension, the activation of upper-body and core muscles ranged between moderate (21-40% maximum voluntary isometric contraction (MVIC)) and very high (>60% MVIC). Muscle activation in these same muscle groups was greater with suspension exercises relative to comparable traditional exercises, except for the inverted row. Muscle activation in the upper extremity and core muscles varied greatly amongst studies.

Objectives Compare the ability of commonly used comparison models to detect neuromuscular asymmetries. A secondary purpose was to determine which neuromuscular task(s) has the greatest sensitivity to identify asymmetries based on the ASI (asymmetry index) calculation. Methods Elite female youth basketball players (N = 29, age = 15.7 ± 1.34 y) performed the single leg countermovement jump in vertical, horizontal, and lateral directions, the star excursion balance test in the anterior, posteromedial, and posterolateral directions, and the sprint test with change of direction. Paired t-tests compared right and left limbs, the dominant (DL) and non-dominant (NDL) limbs, and the more/less skillful limbs. Results The coincident identification between the more skillful leg and the leg subjectively described as the DL was low for all of the tasks performed (35%–52%). There were significant differences between the more and less skillful legs for all tasks, while performances between the right and left limbs and DL and NDL differed significantly for only one task each. The largest ASI detected in this study was found in the vertical single leg countermovement jump (14.11%). Conclusions The skillful limb model of comparison may be more useful than other models to detect neuromuscular asymmetries.

Rationale and objectives The quantity and quality of research in physiotherapy has increased exponentially during the past decades. However, retrieving publications associated with this field of research is difficult. The aim of this study is to identify and describe controlled clinical trials (CCT) published in Spanish physiotherapy journals using electronic and handsearching strategies. Method Observational study through which we identified eligible journals in order to retrieve CCTs using electronic and handsearching strategies, as proposed by the Cochrane Collaboration. A descriptive analysis of the main characteristics of these CCTs was completed. Results Seventy-eight CCTs were identified in 10 eligible journals, none of which were indexed in the major databases. 16.7% of the identified studies were multicentric. Traumatology and orthopaedics was the most studied field (33.3%) followed by neurology (15.4%). The most researched health problems were back pain (17.24%) fibromyalgia, arthrosis and stroke (6.8% each). Measured outcomes varied greatly, including pain control, functional mobility and quality of life. Most CCTs (64.1%) had a high risk of bias. Conclusions The number of CCTs published in Spanish physiotherapy journals is limited. Handsearching these journals is essential, since none is indexed in major databases. In general, the identified CCTs carry a high risk of bias.

Objectives To assess the efficacy of an exercise program on a whole-body vibration platform (WBV) in improving body balance and muscle performance and preventing falls in institutionalized elderly people. Design/Setting/Participants A multicentre randomized parallel assessor-blinded clinical trial was conducted in elderly persons living in nursing homes. Interventions Participants were randomized to an exercise program performed either on a whole body vibratory platform (WBV plus exercise group) or on a stationary surface (exercise group). The exercise program for both groups consisted of static and dynamic exercises (balance and strength training over a 6-week training period of 3 sessions per week). The frequency applied on the vibratory platform was 30 to 35 Hz and amplitude was 2 to 4 mm. Measurements The primary outcome measurement was static/dynamic body balance. Secondary outcomes were muscle strength and number of falls. Efficacy was analyzed on an intention-to-treat basis and per protocol. The effects of the intervention were evaluated using the t test, Mann-Whitney test, or chi-square test, depending on the type of outcome. Follow-up measurements were collected 6 weeks and 6 months after randomization. Results A total of 159 participants from 10 centers were included: 81 in the WBV plus exercise group and 78 in the control group. Mean age was 82 years, and 67.29% were women. The Tinetti test score showed a significant overall improvement in both groups ( P P = .890) or month 6 ( P = .718). The Timed Up and Go test did not improve ( P = .599) in either group over time, and no significant differences were found between groups at week 6 ( P = .757) or month 6 ( P = .959). Muscle performance results from the 5 Sit-To-Stand tests improved significantly across time ( P = .001), but no statistically significant differences were found between groups at week 6 ( P = .709) or month 6 ( P = .841). A total of 57 falls (35.8%) were recorded during the follow-up period, with no differences between groups ( P = .406). Conclusion Exercise program on a vibratory platform provides benefits similar to those with exercise program on a stationary surface in relation to body balance, gait, functional mobility, and muscle strength in institutionalized elderly people. Longer studies in larger samples are needed to assess falls.

Objective The primary aim of this systematic review was to determine if inertial flywheel resistance training is superior to gravity-dependent resistance training in improving muscle strength. The secondary aim was to determine whether inertial flywheel resistance training is superior to gravity-dependent resistance training in improving other muscular adaptations. Design A systematic review with meta-analyses of randomised and non-randomised controlled trials. Methods We searched MEDLINE, Scopus, SPORTDiscus, Web of Science and Cochrane Central Register of Controlled Trials with no publication date restrictions until November 2016. We performed meta-analyses on randomised and non-randomised controlled trials to determine the standardized mean difference between the effects of inertial flywheel and gravity-dependent resistance training on muscle strength. A total of 76 and 71 participants were included in the primary and secondary analyses, respectively. Results After systematic review, we included three randomised and four non-randomised controlled trials. In the primary analysis for the primary outcome muscle strength, the pooled results from randomised controlled trials showed no difference (SMD = −0.05; 95%CI −0.51 to 0.40; p = 0.82; I 2 = 0%). In the secondary analyses of the primary outcome, the pooled results from non-randomised controlled trials showed no difference (SMD = 0.02; 95%CI −0.45 to 0.49; p = 0.93; I 2 = 0%; and SMD = 0.03; 95%CI −0.43 to 0.50; p = 0.88; I 2 = 0%). Meta-analysis on secondary outcomes could not be performed. Conclusion Based on the available data, inertial flywheel resistance training was not superior to gravity-dependent resistance training in enhancing muscle strength. Data for other strength variables and other muscular adaptations was insufficient to draw firm conclusions from.

Gual, G, Fort-Vanmeerhaeghe, A, Romero-Rodríguez, D, and Tesch, PA. Effects of in-season inertial resistance training with eccentric overload in a sports population at risk for patellar tendinopathy. J Strength Cond Res 30(7): 1834-1842, 2016-Volleyball and basketball players can be considered as a population at risk for patellar tendinopathy. Given the paradox that eccentric training elicits therapeutic benefits yet might provoke such injury, we investigated the influence of a weekly bout of inertial squat resistance exercise offering eccentric overload on lower limb muscle power and patellar tendon complaints. Players of 8 (4 basketball and 4 volleyball) teams (38 women and 43 men) were randomly assigned to either the intervention (IG) or control (CG) group. Although IG and CG maintained scheduled in-season training routines over 24 weeks, IG, in addition, performed 1 weekly session of eccentric overload by 4 sets of 8 repetitions of the squat using flywheel inertial resistance. Victorian Institute of Sports Assessment patellar tendinopathy questionnaire (VISA-p), vertical countermovement jump, and squat power, both concentric (Squat-Con) and eccentric (Squat-Ecc), tests were performed before (T1), during (T2), and after (T3) the 24 weeks of intervention. Neither group suffered from patellar tendinopathy during the study period. VISA-p displayed no differences across groups at any measurement period. Countermovement jump scores significantly (p ≤ 0.05) differed between groups in favor of the IG. Both Squat-Con and Squat-Ecc mean scores from the IG were significantly (p0.01) higher than the CG. Adding a weekly eccentric overload squat training bout to a regular basketball and volleyball exercise routine enhances lower limb muscle power without triggering patellar tendon complaints. Future studies, using the current exercise paradigm, aim to explore its efficacy to prevent or combat patellar tendinopathy in sports calling for frequent explosive jumps.

Introducción y objetivos: Estudio de intervención de diseño longitudinal con una duración de 6 meses, de grupo único con evaluación antes-después, que pretende evaluar la eficacia de un programa propioceptivo como método de prevención de lesiones de extremidad inferior en jóvenes deportistas. Métodos: La muestra de estudio fueron 28 jugadores de voleibol de ambos sexos (15-18 años). Se tomaron datos durante el primer trimestre sin intervención y durante el siguiente trimestre con entrenamiento. El entrenamiento propioceptivo utilizado siguió las bases de la terapia reequilibradora del aparato locomotor (TRAL). Se midió semanalmente el dolor mediante la escala analógica del dolor y la incidencia de lesiones en la extremidad inferior de la temporada de estudio y en las mismas fechas de la temporada anterior. Resultados: Durante el período de entrenamiento propioceptivo se produjo una reducción significativa del dolor de tobillo en ambos sexos ­en el caso del dolor de rodilla sólo en chicas­ y una tendencia a la disminución de la incidencia de lesiones deportivas de la extremidad inferior en ambos sexos, especialmente de tobillo. Conclusiones: El entrenamiento propioceptivo disminuye la presencia y la intensidad de dolor de rodilla en el caso de las chicas, tiende a la mejora en los chicos; mejora la presencia y la intensidad de dolor de tobillo en ambos sexos; y en el caso de la incidencia de lesiones deportivas existe una clara tendencia a la disminución de lesiones de tobillo.

Background Institutionalized older persons have a poor functional capacity. Including physical exercise in their routine activities decreases their frailty and improves their quality of life. Whole-body vibration (WBV) training is a type of exercise that seems beneficial in frail older persons to improve their functional mobility, but the evidence is inconclusive. This trial will compare the results of exercise with WBV and exercise without WBV in improving body balance, muscle performance and fall prevention in institutionalized older persons. Methods/Design An open, multicentre and parallel randomized clinical trial with blinded assessment. 160 nursing home residents aged over 65 years and of both sexes will be identified to participate in the study. Participants will be centrally randomised and allocated to interventions (vibration or exercise group) by telephone. The vibration group will perform static/dynamic exercises (balance and resistance training) on a vibratory platform (Frequency: 30-35 Hz; Amplitude: 2-4 mm) over a six-week training period (3 sessions/week). The exercise group will perform the same exercise protocol but without a vibration stimuli platform. The primary outcome measure is the static/dynamic body balance. Secondary outcomes are muscle strength and, number of new falls. Follow-up measurements will be collected at 6 weeks and at 6 months after randomization. Efficacy will be analysed on an intention-to-treat (ITT) basis and 'per protocol'. The effects of the intervention will be evaluated using the "t" test, Mann-Witney test, or Chi-square test, depending on the type of outcome. The final analysis will be performed 6 weeks and 6 months after randomization. Discussion This study will help to clarify whether WBV training improves body balance, gait mobility and muscle strength in frail older persons living in nursing homes. As far as we know, this will be the first study to evaluate the efficacy of WBV for the prevention of falls. Trial Registration ClinicalTrials.gov: NCT01375790

Background Whole-body vibration (WBV) may be a complementary training to standard physical rehabilitation programmes and appears to have potential benefits in the sensorimotor system performance of patients with neurodegenerative diseases. Objectives The aim of this review was to examine the efficacy of WBV to improve functional performance according to basic activities of daily living (ADL) in neurodegenerative diseases. Additionally, we wanted to assess the possible effect on signs and symptoms of the disease, body balance, gait, muscle performance, quality of life and adverse events. Search methods We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2011 Issue 4), MEDLINE (1964 to 6 May 2011; via PubMed), EMBASE (1980 to 6 May 2011; via Ovid), PeDro (1929 to May 2011; via website), CINAHL (to September 2011; via Ovid) and PsycINFO (1806 to 6 May 2011; via Ovid). Selection criteria We included randomised controlled trials comparing single or multiple sessions of WBV to a passive intervention, any other active physical therapy or WBV with different vibration parameters. Data collection and analysis Two review authors independently selected trials for inclusion, assessed trial quality and extracted data. Disagreement was resolved by discussion or, if necessary, referred to a third review author. Main results We included 10 trials, of which six focused on Parkinson's disease and four on multiple sclerosis. None of the studies reported data on the primary outcome (functional performance). In Parkinson's disease, after pooling two studies, a single session of WBV caused a significant improvement of gait measured using the Timed Up and Go test (TUG) in comparison to standing exercises (mean difference -3.09, 95% confidence interval -5.60 to -0.59; P = 0.02; I2 = 0%). Nevertheless, longer duration of WBV did not show significant results in comparison with physical therapy in body balance or signs and symptoms measured with the Unified Parkinson's Disease Rating Scale (UPDRS). In multiple sclerosis there was no evidence of a short-term or long-term effect of WBV on body balance, gait, muscle performance or quality of life. Adverse events were reported in few trials. In those trials that reported them, the intervention appeared to be safe. Authors' conclusions There is insufficient evidence of the effect of WBV training on functional performance of neurodegenerative disease patients. Also, there is insufficient evidence regarding its beneficial effects on signs and symptoms of the disease, body balance, gait, muscle strength and quality of life compared to other active physical therapy or passive interventions in Parkinson's disease or multiple sclerosis. More studies assessing other functional tests and accurately assessing safety are needed before a definitive recommendation is established.