Kinematic characteristics of novices’ sprint techniques at maximum velocity phase

Topics in Exercise Science and Kinesiology Volume 5: Issue 1, Article 2, 2024. Sprint performance is a crucial aspect of achieving high performance across a range of sports. However, previous studies analyzing the sprint technique of novices have yielded disparate findings regarding effective sprint techniques. For instance, Saito and Ito (1995) found no significant difference in the maximum thigh angle of the free leg between boys aged 7 to 12 and sprinters. Conversely, Katoh et al. (2001) reported that elementary school sprinters indicated a larger maximum thigh angle of the free leg than novice elementary children. Inconsistency like this makes it challenging for teachers to plan coaching strategies for refinement sprint techniques. This study aimed to clarify the kinematic characteristics of novices ranging from elementary school children to adults by reviewing previous articles. To comprehensively explore a broad range of English and Japanese articles analyzing sprint techniques of novices and athletes during the maximal velocity phase in sprint events, three search engines, namely CiNii Research, PubMed, and SPORTDiscus, were utilized. Mean values, correlation coefficients, and the results of group comparisons in these articles were compared. As the main results, novices exhibited a much smaller thigh angle of the free leg at touchdown compared to athletes. Novices indicated a larger minimum knee angle of the free leg than athletes, and this angle tended to decrease as sprint velocity increased from 5 m/s to 10 m/s. Novices exhibited a smaller maximum thigh angle of the free leg than athletes, and this angle tended to increase as sprint velocity increased from 5 m/s to 9 m/s

Angular momentum in skilled kicking pullover performed by elementary school children

Topics in Exercise Science and Kinesiology Volume 3: Issue 1, Article 2, 2022. This study aimed to clarify the differences in body positions and the role of the swing leg, support leg, and head-arm-trunk segment in generating and maintaining angular momentum of the whole body about a horizontal bar as well as how to improve the skill level of successful kicking pullover attempts. Two-dimensional kinematic parameters of successful kicking pullover attempts and body composition indices of 26 fifth-grade elementary school children were collected. Their techniques were classified into excellent and good groups based on the subjective evaluation of three evaluators. Although there were no significant differences in body composition indices between the two groups, the motion phase time during the 4th phase and the total time of the excellent group were significantly shorter compared with the good group. Also, the counterclockwise rotation of the angular momentum of the head-arm-trunk segment and the whole body during the 4th phase was significantly larger in the excellent group than in the good group. These results suggest that maintaining the angular momentum of the head-arm-trunk segment during the 4th phase leads to attempts with shorter time and improves skill levels from the good group to the excellent group. The good group was not able to maintain angular momentum of the whole body during the 4th phase because the peak of the angular momentum of the head-arm-trunk segment and support leg tended to appear earlier than in the excellent group. we newly clarified that teachers need to focus on the body position of the trunk and head during the 4th phase in order for elementary school children to succeed in kicking pullovers more beautifully at a higher level

Comparison of Physical Fitness between Sport and Non-Sport Groups among Elementary School Children

We compared physical fitness factors between sport and non-sport groups of elementary school children in all grades. The subjects of this study were 1,079 1st- to 6th-grade male elementary school children. Their parents completed a questionnaire examining whether the child attended sports lessons as a regular after-school activity. Physical fitness was evaluated by a new physical fitness test recommended by the Japanese Ministry of Education, Culture, Sports, Science, and Technology (4). The test consists of the following items: 1) Grip strength (kg); 2) Sit-ups (number completed in 30 sec); 4) Sitting front stretches (cm); 5) Side steps (number completed in 20 sec); 6) 20-m shuttle run (number of repetitions); 7) 50-m run (sec); 8) Standing long jump (m); 9) Softball throw (m); 10) Height (m); and 11) weight (kg). Point of application ＃1: In regards to the sit-ups, 20-m shuttle run, and softball throw, children who attend sports lessons after school showed a better performance compared to children who do not attend sport lessons, especially after the 3rd grade. Point of application ＃2: Performance in physical fitness that requires complex movements, such as the side steps and 50-m run, were susceptible to sports lessons. Point of application ＃3: Flexibility and performance in physical fitness that require simple movement, such as the grip strength and standing long jump, were not affected significantly by sport lessons during elementary school ages