Assessing Limb Dominance and Interlimb Asymmetries Over Multiple Angles During Change of Direction Speed Tests in Basketball Players

Determination of change of direction deficit thresholds across a spectrum of angles in basketball players

Change of direction deficit (CODD) offers valuable insights into a player's balance between linear and multidirectional speed. However, there are still no established reference values for CODD. The objectives of this study were to determine CODD thresholds for various change of direction angles in basketball players according to gender and analyse the relationships between CODD and execution time in speed tests. One hundred and thirty basketball players (46% female; age: 23.7 ± 5.29 years; height: 189.1 ± 11.1 cm; body mass: 84.3 ± 15.7 kg) undertook 10-m linear and change of direction speed test at 45º, 90º and 180º. A k-means cluster analysis was conducted to standardise CODD thresholds and a one-way analysis of variance to identify the differences between clusters. The results revealed angulation-specific CODD thresholds, ranging from 3% to 8%, 17% to 25% and 43% to 51% for 45º, 90º and 180º cutting angles, respectively for the pooled sample. Furthermore, differences inter-clusters (p < 0.05) were observed for execution time at all cutting angles for both genders. Therefore, strength and conditioning coaches are encouraged to assess CODD as a highly valid variable for evaluating change of direction performance and to use current CODD thresholds to tailor training programmes according to each athlete's needs.

The Influence of Functional Movement and Strength upon Linear and Change of Direction Speed in Male and Female Basketball Players

The present study aimed to analyse the relationship between functional movement and strength variables upon linear speed (Ls) and change of direction (COD) based on gender. It also aimed to identify the determinants of performance of Ls and COD according to gender. Fifty basketball players (54% female) completed the assessment in which the weight-bearing dorsiflexion test, the Y-balance test, the unilateral countermovement jump, the unilateral drop jump, the unilateral triple hop test, Ls and CODs were performed. Speed variables were divided according to time execution into "low-performance" and "high-performance" to establish a comparison between performance groups. Strength variables significantly influenced speed tests' performance in both genders (p < 0.05). For males, the greater the Ls, the higher the change of direction deficit (p < 0.001). Multiple regression analysis revealed that a long and vertical stretch-shortening cycle (SSC) was the most influential physical ability for speed performance in females (45-65% variance explained; p < 0.001), while in males, a short and horizontal SSC played a significant role (30-61% variance explained; p < 0.022). These results suggest that gender should be considered in programming strength training to improve speed, as each gender will benefit most from the application of different force-orientations and different SSC. Also, the faster the male players were in Ls, the less efficient they were in the COD performance. This is why for men, it would be recommended to perform eccentric exercises along with deceleration and technique drills to improve COD speed.

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.