Validity and Test-Retest Reliability of the TIVRE-Basket Test for the Determination of Aerobic Power in Elite Male Basketball Players.

The aims of this study were to (a) determine the relationship between performance on the court-based TIVRE-Basket test and peak aerobic power determined from a criterion laboratory-based incremental treadmill test and (b) to examine the test-retest reliability of the TIVRE-Basket test in elite male basketball players. To address aim 1, 36 elite male basketball players (age: 25.2 ± 4.7 years, weight: 94.1 ± 11.4 kg, height: 195.83 ± 9.6 cm) completed a graded treadmill exercise test and the TIVRE-Basket within 72 hours. The mean distance recorded during the TIVRE-Basket test was 4001.8 ± 176.4 m, and mean VO2 peak was 54.7 ± 2.8 ml · kg(-1) · min(-1), and the correlation between the 2 parameters was r = 0.824 (p ≤ 0.001). Linear regression analysis identified TIVRE-Basket distance (in meters) as the only unique predictor of VO2 peak in a single variable plus constant model: VO2 peak = 2.595 + (0.13 × TIVRE-Basket distance [in meters]). Performance on the TIVRE-Basket test accounted for 67.8% of the variance in VO2 peak (t = 8.466, p ≤ 0.001, 95% confidence interval: 0.01-0.016, SEE: 1.61). To address aim 2, 20 male basketball players (age: 26.7 ± 4.2 years, height: 1.94 ± 0.92 cm, weight: 94.0 ± 9.1 kg) performed the TIVRE-Basket test on 2 occasions. There was no significant difference in total distance covered between trial 1 (4138.8 ± 677.3 m) and trial 2 (4188.0 ± 648.8 m; t = 0.5798, p = 0.5688). Mean difference between trials was 49.2 ± 399.5 m, with an intraclass correlation coefficient of 0.85 suggesting a moderate level of reliability. Standardized typical error of measurement was 0.88%, representing a moderate degree of trial-to-trial error, and the Coefficient of Variation (CV) was 6.3%. The TIVRE-Basket test therefore represents a valid and moderately reliable court-based sport-specific test of aerobic power for use with individuals and teams of elite-level male basketball players. Future research is required to ascertain its validity and reliability in other basketball populations, for example, across age groups, at different levels of competition, in females and in different forms of the game, for example, wheelchair basketball.

Validation of a new method to measure contact and flight times during treadmill running.

The purpose of this study was to validate a new method to measure contact and flight times during treadmill running and to test its reliability and sensitivity. Fifteen well-trained runners performed 7 sets of running at different speeds (from 10 to 22 km·h). Contact and flight times were simultaneously recorded by a high-speed video system (gold standard method) and a new method based on laser technology (SportJump System Pro). Athletes were classified according to their foot strike pattern (rearfoot vs. midfoot and forefoot). The new method overestimated the contact time and underestimated the flight time with respect to the gold standard method (p < 0.001). However, relationships and intraclass correlation coefficients (ICCs) between both systems were very strong (r and ICC > 0.99, p < 0.001). Contact time differences between the 2 systems depended on running speed (p < 0.001) but not on foot strike pattern or runners' body mass. This allowed to correct the differences in contact time and flight time. The new method was sensitive for detecting small differences in contact time (<20 ms) when the running speed increased and when the type of foot strike patterns changed. Additionally, a low intraindividual step variability (coefficient of variation = 2.0 ± 0.5%) and high intra- (ICC = 0.998) and interobserver (ICC = 0.977) reliability were shown. In conclusion, the new method was validated, being reliable and sensitive for detecting small differences in contact and flight times during treadmill running. Therefore, it could be used to compare biomechanical variables between groups in cross-sectional studies and to verify the influence of some independent variables (i.e., training, running economy, or performance) on running biomechanics.

The type of mat (Contact vs. Photocell) affects vertical jump height estimated from flight time.

The purposes of this study were to analyze the validity and reliability of 2 photocell mats and to probe the possible influence of the type of mat (contact vs. photocell) on vertical jump height estimated from flight time. In 2 separate studies, 89 and 92 physical students performed 3 countermovement jumps that were simultaneously registered by a Force Plate (gold standard method), 2 photocell mats (SportJump System Pro and ErgoJump Plus), and a contact mat (SportJump-v1.0). The first study showed that the 2 photocell mats underestimated the vertical jump height (1.3 ± 0.2 cm and 5.9 ± 5.2 cm, respectively), but only SportJump System Pro showed a high correlation with the Force Plate (r = 0.999 and 0.676, respectively) and good intraday reliability (coefficient of variation = 2.98 and 15.94%, intraclass correlation coefficients = 0.95-0.97 and 0.45-0.57, respectively). The second study demonstrated a strong correlation (r = 0.994) between the 2 technologies (contact vs. photocell mats) with differences in vertical jump height of 2.0 ± 0.8 cm (95% confidence interval = 1.9-2.1 cm), which depended on both flight time and subjects' body mass. In conclusion, SportJump System Pro was a valid and reliable device. The new devices to measure vertical jump height from flight time should be validated. The type of mat (contact vs. photocell) affected approximately 6% the vertical jump height (approximately 2 cm in this study), which should be considered in further studies. The use of validated photocell mats instead of the contact mats was recommended.

Validity, Reliability, and Sensitivity of a Volleyball Intermittent Endurance Test.

PURPOSE: To analyze the concurrent and construct validity of a volleyball intermittent endurance test (VIET). The VIET's test-retest reliability and sensitivity to assess seasonal changes was also studied. METHODS: During the preseason, 71 volleyball players of different competitive levels took part in this study. All performed the VIET and a graded treadmill test with gas-exchange measurement (GXT). Thirty-one of the players performed an additional VIET to analyze the test-retest reliability. To test the VIET's sensitivity, 28 players repeated the VIET and GXT at the end of their season. RESULTS: Significant (P < .001) relationships between VIET distance and maximal oxygen uptake (r = .74) and GXT maximal speed (r = .78) were observed. There were no significant differences between the VIET performance test and retest (1542.1 ± 338.1 vs 1567.1 ± 358.2 m). Significant (P < .001) relationships and intraclass correlation coefficient (ICC) were found (r = .95, ICC = .96) for VIET performance. VIET performance increased significantly (P < .001) with player performance level and was sensitive to fitness changes across the season (1458.8 ± 343.5 vs 1581.1 ± 334.0 m, P < .01). CONCLUSIONS: The VIET may be considered a valid, reliable, and sensitive test to assess the aerobic endurance in volleyball players.

Validation of a tactical analysis methodology for the study of pick and roll in basketball

El objetivo de esta investigación se centra en el diseño y validación de una propuesta metodológica de análisis táctico para el estudio del bloqueo directo en baloncesto, aplicando los principios de la metodología observacional y el registro contextualizado de acciones. Se han desarrollado tres fases: Fase 1) Identificación y selección de variables, donde se han definido y catalogado las variables conductuales (bloqueo directo), contextuales (zona del campo, tiempo de posesión y periodo de juego) y evaluativas (resultado de la acción). Fase 2) Creación ad hoc de instrumentos de registro, en la que se ha adaptado una herramienta informática (software VA-Sports: Baloncesto) para atender a las particularidades y necesidades específicas del estudio de acciones de bloqueo directo. Fase 3) Control de la calidad del dato, en la que se fijaron los criterios de selección de la muestra, se desarrolló el proceso de entrenamiento de observadores, y se verificó el nivel de acuerdo interno o concordancia intraobservador, para evaluar la fiabilidad de la propuesta metodológica. Fueron analizadas un total de 192 acciones de bloqueo directo correspondientes a 6 partidos completos de la Liga ACB española. Se pudo constatar una elevada fiabilidad de la propuesta metodológica diseñada que, en su conjunto obtuvo un elevado valor promedio de Kappa (0.994), lo que permite concluir que las variables de análisis propuestas resultan precisas, en su definición y categorización para estudiar acciones de bloqueo directo. Las variables tiempo de posesión, periodo de juego y resultado de la acción, han evidenciado un nivel de concordancia máximo (valor Kappa de 1.000), al tiempo que las variables bloqueo directo y zona del campo, también han evidenciado un grado de objetividad elevado (valores de Kappa de .990 y .981 respectivamente) (AU)

This study examines the design and validation of a tactical analysis methodology proposal for the study of pick and roll in basketball, applying the principles of observational methodology and the recording of actions in their natural context. We have developed three phases: Phase 1) Identification and selection of analysis variables, in which behavioral variables have been identified and cataloged (pick and roll), contextual analysis variables (court area, time of possession and period of play) and evaluative analysis variables (result of the action); Phase 2) Ad hoc creation of recording instruments, in which a computer tool was adapted (VA-Sports Software: Basketball) to address the particularities and specific needs of the study of the pick and roll situations.; and Phase 3) Quality control of the data, in which selection criteria were set for the sample, the training process of the observers was carried out, and the level of internal agreement and intraobserver concordance were verified in order to assess the reliability of the methodological approach. A total of 192 pick and roll situations corresponding to 6 games of the Spanish ACB League were analyzed in this study. The results suggest a high level of reliability of the methodology designed; as a whole it earned a high average Kappa value (.994), leading to the conclusion that the proposed analysis variables are precise in their definition and categorization in order to study pick and roll situations. The analysis variables; time of possession, period of play and results of the action showed a maximum level of agreement (Kappa value 1.000), while the analysis variables; pick and roll and court area also show a high degree of objectivity (Kappa values of .990 and .981 respectively) (AU)