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.

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 were compared, 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 the 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. 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.

Neuromuscular and biomechanical imbalances that exist in jumping and landing actions should be examined in order to intervene to decrease the risk of ACL injury. The main aim of this study was to analyse and compare, by chronological age, jumping and landing deficits in young female handball players using the Tuck Jump Assessment (TJA). A secondary aim was to relate the qualitative asymmetry values detected using the TJA to the quantitative asymmetry values detected starting from the single leg countermovement jump (SL-CMJ). Sixty-one young female handball players (age: 14.3 ± 1.5 years) were distributed into three groups: U12, U14 and U16 and performed the TJA test and the single leg countermovement jump (SL-CMJ). The female U12 category players obtained the highest scores in the TJA and there were significant differences between the U12 (12.11 ± 1.97) and U14 (10.89 ± 1.74) categories (p = 0.017; ES = 0.374). In the U12 category, the female players presented larger interlimb asymmetry magnitudes in the SL-CMJ test; they also obtained higher scores in the qualitative criteria of the TJA test that referred to asymmetry (r = 0.43; p = 0.027). The analysis of the jumping and landing pattern using TJA allowed us to identify that the lower extremity valgus at landing, foot contact timing not equal and landing contact noise are the main biomechanical deficits in young female handball players. Furthermore, the asymmetry values assessed qualitatively (TJA) are associated with the asymmetry values assessed quantitatively (difference in jump achieved with each limb in the SL-CMJ test) in younger categories.