Several studies have shown that force application is influenced by different neuromuscular mechanisms depending on the time of force application analysis in isometric knee extension test (IKE), and a countermovement jump (CMJ) has contributions from knee extension, so some CMJ variables could be indicators of such mechanisms. Purpose: The aim of this study was to determine the level of relationship of variables of IKE and bilateral CMJ tests. Methods: Male college soccer players (n = 25; corporal mass = 72 ± 8 kg; height = 171 ± 5 cm; age = 22 ± 2 years) performed the IKE at two angles (60° and 75°) on an isokinetic machine and the CMJ on two uniaxial force platforms. To determine the level of relationship, Pearson’s correlation coefficient was analyzed between the test variables. Results: Trivial to moderate correlations (r = −0.45 to 0.62; p < 0.05) were found between CMJ variables and IKE in both knee angles (60° and 75°); Conclusions: The variables of IKE have a trivial to moderate correlation with the variables of CMJ, so the variables of CMJ could not be considered interchangeably with those of IKE and therefore considered indicators of neuromuscular mechanisms isolated from the knee extensor function. Longitudinal design (fatigue or training protocols) should be realized to corroborate these results.

The running cycle is distinguished from the gait cycle by the presence of a flight phase and distinct biomechanical characteristics. Despite existing frameworks for the temporal segmentation of running, these models remain underutilized in comprehensive biomechanical analyses, particularly for delineating phases, subphases, and key events. This study aims to provide a review of historical and contemporary temporal models of the running cycle and to introduce a unified structure designed to enhance analytical precision. The proposed framework divides the running cycle into two primary phases: (a) contact (subdivided into braking and propulsion subphases) and (b) flight, together with three critical events: (1) initial contact, (2) transition of braking–propulsion, (3) toe-off. While leg swing is not considered a phase in this framework due to temporal overlap with other phases, its recognized importance in running mechanics warrants its integrated analysis under the proposed temporal phase delineation. Additionally, methodologies for identifying these events through dynamometry and motion capture are evaluated, emphasizing their role in contextualizing kinetic and kinematic data. By integrating this temporal structure, the study aims to standardize biomechanical assessments of running technique, fostering more consistent comparisons across studies. Such integration has the potential to not only refine interpretations of running mechanics but also to enable practical advancements in athletic training, injury mitigation, and performance optimization.

Objective: A systematized review was carried out to identify the studies that during the last ten years have used isokinetic equipment in sports in which the upper extremity is the basis of its practice, to provide an updated and detailed view of its use, methodologies and the variables used to express their results. Methods: A systematized search of 10 years of information was carried out, according to the PRISMA process, in the databases: Scopus, Web of Science, Pubmed, CINAHL, using combined terms: «isokinetic» «upper extremity», «upper limb», « sport», «exercises», «upper extremity». Results: 9406 articles were identified in the databases for review, of which only 46 were selected based on inclusion criteria. Among the sports evaluated, 25 articles correspond to sports with overhead throws (basketball, volleyball, baseball, handball, among others), followed by Paralympic sports with six articles (basketball and volleyball). Sports such as swimming, judo, weightlifting, water polo, or combined sports complete the list. The shoulder rotator muscles were the most evaluated and the concentric-concentric modality was the most used. The variable moment is the most reported, but the evaluation methodologies and selected speeds differ significantly between studies. Conclusion: The methodologies used are varied (i.e., selection of speed, type of muscular contraction, positioning, and dominance), and their selection was not always oriented toward the functionality of sports practice. In addition, it was observed that some studies needed to specify the isokinetic modality used, leaving a gap in relevant information within the study methods and affecting their future replicability. Keywords: Isokinetic evaluation; Isokinetic; upper extremity sports; upper limb.

Background: The high demands of professional soccer predispose players to musculoskeletal injuries. The primary challenge for identifying potential risk factors lies in determining the appropriate assessment methods and indicators to consider. Kinetic variables have been identified as potential indicators of injury risk. Objectives: To conduct a systematic review of the literature analyzing the relationship between kinetic variables and the risk of indirect musculoskeletal injuries of the lower limb in professional soccer players. Methods: A search was conducted on Web of Science, PubMed, and Scopus following the PRISMA guidelines. The search included articles that link kinetic variables assessed through dynamometry to indirect lower limb injuries. Sample characteristics, assessments, injury follow-ups, and statistical results were extracted for qualitative synthesis. Results: A total of 1096 studies were initially identified, of which 380 duplicates were removed. After screening 716 articles by title and abstract, 631 were excluded. Subsequently, 85 full-text articles were examined, resulting in 11 studies being included. Of the included articles, 10 used isokinetic dynamometry and the Nordic hamstring curl test to assess lower limb strength. Conclusions: The results of this review indicate that kinetic variables, particularly isokinetic strength measures at different angular velocities, are consistently associated with indirect musculoskeletal injury risk in professional soccer players. The most relevant indicators include eccentric hamstring force and concentric quadriceps torque, which help identify strength deficits and muscular disequilibrium. Monitoring these variables through validated assessments enables the development of targeted prevention strategies. Additionally, injury risk assessment should integrate kinetic data with contextual indicators such as well-being, fatigue, and training load.

BACKGROUND: Long-time judo training can lead athletes to develop upper limb asymmetry and shoulder asymmetry during force production, mainly in the action of pulling, pushing, and throwing; that requires higher strength and velocity of the internal a

Background/Aims: Asymmetry of the internal (IR) and external (ER) shoulder rotators can increase the risk of injuries in judokas. Discrete analyses are usually performed in time series data, but they can have biases by removing trends, so other approaches have been proposed to avoid these biases such as statistical parametric mapping (SPM) and principal component analysis (PCA). This study analyzed the asymmetry in the shoulder rotators in female judokas, comparing dominant (D) vs. non-dominant (ND) upper limbs. Methods: For this, 11 elite athletes (age: 20.1 ± 2.9 yrs.; experience: 4.0 ± 0.5 yrs.; body mass: 66.0 ± 14.6 kg; height: 1.6 ± 0.1 m; BMI: 24.8 ± 4.3 kg/m²), were evaluated in an isokinetic dynamometer (Cybex^® Humac/Norm Dynamometer CSMI, 502140, Stoughton, MA, USA). All participants performed the concentric (CON/CON) isokinetic evaluations of internal and external rotation of the shoulder in 60°/s and 180°/s angular velocities. Results: There was no significative asymmetry between IR vs. ER at 60°/s; similar results were observed at 180°/s when analyzed by PCA or SPM methods (p > 0.05 for all comparison). There was no difference between peak torque at 60°/s or 180°/s (p > 0.05 for all comparison). Conclusions: no asymmetry was observed in IR and ER in elite female athletes, regardless of the analysis method.