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The purpose of this study was to compare the step parameters, the Body Center of Mass (BCM) kinematics, as well as the angular and linear kinematics of the lower extremities' joints of prepubescent and adult sprinters of both sexes. A total of forty-two athletes were examined, including adult men (AM) and women (AF) as well as preadolescent boys (PPB) and girls (PPG). A 2D-DLT analysis was conducted on video recordings (sampling frequency: 100 fps) of the participants' maximum effort trial while in their maximum sprinting velocity phase. A 2 (age) × 2 (sex) ANOVA revealed significant (p < 0.05) effects of the factors age and sex, and an interaction of age × sex in the sprint running velocity. It was also found that the spatiotemporal structure of the step parameters was significantly (p < 0.05) different between AM and AF but not between PPB and PPG. Also, a significant (p < 0.05) main effect of age was evident mainly for the ankle joint of both legs, as well as for the angular kinematics of the swing leg's knee joint. In conclusion, apart from the possible disparities in training experience, differences due to age and sex exist in the step parameters and the kinematics of the sprinting technique due to differences in the technical elements related to coordination, strength application capability, and stiffness. [ABSTRACT FROM AUTHOR]

Recently, a variety of technical approaches in world-class pole-vaulters' behaviour have been observed. The aim of this study was to investigate the presence of subgroups using different technical approaches and to compare biomechanical performance differences. Biomechanical analysis of performances over 5.00 metres from 99 athletes were clustered with K-means methodology based on the relative position of the top hand at take-off and the direction of the top of the pole from take-off to the maximal pole bending. Analysis revealed four subgroups that were distinguished by higher and lower direction angle and relative position values. Despite differences in technique, the analysis did not reveal significant differences between these four groups in performance, take-off speed, or athlete anthropometrics. Nevertheless, these clusters showcased variations in pole–athlete interactions and pole bending, suggesting different strategies and physical requirements associated with each approach. Cluster 2 characterised the classical technique with a high direction angle and a take-off position close to the vertical plane. Cluster 4 displayed a technique with a low take-off angle, suggesting the influence of athletes like Lavillenie, in deviating from the conventional model. Understanding and categorising athletes based on their preferred technique can aid coaches in providing tailored instructions, leading to performance improvements. [ABSTRACT FROM AUTHOR]

Drop jump (DJ) performance gain with increasing drop height is well documented in adults, but there is still no clear evidence of such gain in children. This study aimed to examine the differences in DJ performance gain in male adults and prepubescent boys by comparing drop heights tailored to each individual's performance and expressed as a percentage of their squat jump (SJ) performance. Fifteen boys (9–11 y) and 15 men (19–27 y) executed DJs from drop heights that were set at 75%, 100%, 125%, and 150% of their best performance in SJ (DJ75, DJ100, DJ125, and DJ150, respectively). Vertical ground reaction force (vGRF), contact time and kinematics of the lower extremities were captured. The results showed that boys jumped significantly lower than adults in DJs, and both age groups presented jumping gain with increasing drop height, up to DJ125. Boys demonstrated longer total contact time, lower angular velocity and vGRF during the propulsive phase, as well as smaller knee flexion at touchdown and lower reactive strength index. vGRF in DJ75 and DJ100 was lower than in DJ125 and DJ150. The highest value for maximum knee flexion was also presented at DJ150. It is concluded that in prepubescent boys, the appropriate drop height for an effective DJ is linked to their performance in SJ and might be between 75% and 125% of their maximum SJ performance. [ABSTRACT FROM AUTHOR]

Drop jumping performance (DJP) is of high importance in order to achieve sporting performance in both team and individual sports. The purpose of the present study was to compare DJP among athletes from various sports. One hundred thirty-eight male athletes (age: 22.3 [+ or -] 3.6 years, body height: 1.87 [+ or -] 0.08 m, body mass: 81.8 [+ or -] 10.8 kg) from 6 different sports performed drop jumps from 60 cm (DJ60) on a force plate. Results revealed that volleyball players jumped higher (p < 0.001) than other athletes. However, track and field athletes produced higher peak force and higher power output using a shorter upward phase (p < 0.001). Further examination using principal components analysis (PCA) revealed that team sport athletes and single scull rowers exhibited DJP utilizing force and time parameters differently than track and field athletes. Conclusively, DJP was different among athletes of various sports. Furthermore, PCA can be a useful method for evaluating the above mentioned differences and for monitoring drop jumping training programs. KEY WORDS. factor analysis, soccer, volleyball, basketball, handball, rowing

In this study, three different methods of teaching the long jump were evaluated. One hundred and thirty-one students of fifth and sixth grade (Mage = 11.4 ± 0.47 years) were randomly assigned into three groups. The first intervention group (INT) followed a blended learning approach using interactive learning activity software, the second intervention group (INTVF) followed the same method with an added direct video feedback system and the control group (CON) was taught the traditional approach. A pre-post 2D kinematic analysis of the students' body segments' position was conducted. Α two-way mixed ANOVA analysis showed an improvement in all three groups. However, the INTVF group performed significantly better regarding leg joints angles, trunk inclination, and body mass center parameters at take-off, compared to the INT and CON groups. In conclusion, teaching using blended learning, new technologies and direct video feedback seems to support students in developing a more efficient take-off technique in long jump. [ABSTRACT FROM AUTHOR]

Softball was played in the 2020 Olympic Games, after being excluded for two Olympiads, but with almost half of the games played in each Olympiad from 1996 to 2008. Thus, it is of interest to investigate the game-related indicators that differentiate winning and losing teams as well as their contribution to scoring a run, in an attempt to comprehend contemporary Olympic Softball using data from a past Olympic Tournament in which a much larger number of games was played. The purpose of the study was to examine the offensive game-related parameters that distinguish winning and losing teams in Olympic Softball tournaments and to identify the impact of offensive tactical situations where a run is more likely to be scored. Based on a notational analysis scheme, 2,946 game instants were processed using the Sportscout STA v.3.2 software. Crosstabulation analysis with the chi-square tests established that winning teams had significantly (p < .05) more fly ball batting occasions, had less batted balls in the catcher's area and more batted balls directed in the center outfield, as well as larger counts of players on bases, stolen bases and runs batted-in. A decision tree analysis using Chi-squared automatic interaction detection (CHAID) revealed that loading the bases with base-runners, batting the ball in the outfield, stealing a base when advancing the base-runners around the bases and using fly ball batting technique were essential to score a run in Olympic Softball. In conclusion, optimum batting action, fast sprinting, enhanced tactical decision making in batting, base-running and base-stealing contribute to the efficiency of the offensive game-related parameters that contribute to achieve a win at an Olympic Softball game. [ABSTRACT FROM AUTHOR]

A practical assessment of the hurdle clearance technique was carried out applying the technique index (TINDEX), namely the difference between performance in a hurdle race and performance in a respective race without hurdles. The aim of the present study was to examine TINDEX of combined events athletes that competed in all World and European Indoor Athletics Championships. The analysis included the heptathletes who won (n = 84) or did not win (n = 192) a medal, the progress of TINDEX per decade (1990s: n = 75; 2000s: n = 97; 2010s: n = 104) and its correlation with performance (total points won) in heptathlon for a total of 276 cases from the heptathlon 60-m sprint and 60-m hurdle races held from 1993 to 2019. Results revealed that medal winners (median [interquartile range] = 0.99 [0.20] s) had significantly (p < 0.001) lower TINDEX compared to nonmedal winners (1.10 [0.24] s). No significant (p > 0.05) TINDEX differences were observed among the cases in the examined decades. Finally, a significant negative correlation (tb = -0.27, p < 0.001) was observed for TINDEX and performance in heptathlon. In conclusion, hurdle clearance with the minimum time loss is a precondition for success in indoor combined events. [ABSTRACT FROM AUTHOR]

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