著者
内藤 景 苅山 靖 宮代 賢治 山元 康平 尾縣 貢 谷川 聡
出版者
一般社団法人 日本体育学会
雑誌
体育学研究 (ISSN:04846710)
巻号頁・発行日
vol.58, no.2, pp.523-538, 2013 (Released:2013-12-07)
参考文献数
32

The purpose of this study was to clarify the step characteristics during the acceleration phase (0—30 m) of a 100-m sprint with reference to the step-type of sprinters. 59 male collegiate sprinters (season best time: 10.68±0.22 s) were recorded running in 100-m races using 10 high-speed video cameras (300 fps). The step variables, such as step-frequency (SF), step-length (SL), contact time, and flight time of each step in the acceleration phase (0—30 m) and maximum speed phase (30—60 m) were calculated. Cluster analysis was used to classify the subjects according to step-type as indicators for the ratio of SF and SL in the 30—60 m section. In addition, each of the step-type groups was divided into two sub-groups (good and poor sprinters) according to the mean speed in the 30—60 m section. The main results were as follows: (1) Sprinters were classifiable into 3 step-type groups; SL-type (n=22), SF-type (n=24), and Mid-type (n=13). (2) Among these groups, there were no differences in the 100-m race times and mean speeds during the 0—30, 30—60, and 60—100 m sections, although SL-type sprinters were taller and had a higher SLindex than SF-type sprinters. SF-type sprinters took a larger numbers of steps over the 100-m distance and showed a higher SFindex than SL-type and Mid-type sprinters. (3) In the 0—30 m and 30—60 m sections, the contact and flight times of SL-type sprinters were longer than those of SF-type sprinters. (4) In SL-type sprinters, the SF of good sprinters was higher than that of poor sprinters at the 5th step, and the SL of good sprinters was longer than that of poor sprinters from the 7th to 15th steps, and in the 30—60 m section. (5) SF-type sprinters showed no significant differences in the SL, but the SF of good sprinters was higher than that of poor sprinters from the 7th to 16th steps and in the 30—60 m section. These results indicate that there are differences in step characteristics during the acceleration phase according to step-type, and that the step characteristics during the acceleration phase may affect the acceleration ability needed to develop a maximum sprint speed. These findings could be useful for devising training methods for improvement of 100-m sprint performance according to step-type.
著者
山元 康平 宮代 賢治 内藤 景 木越 清信 谷川 聡 大山卞 圭悟 宮下 憲 尾縣 貢
出版者
一般社団法人 日本体育学会
雑誌
体育学研究 (ISSN:04846710)
巻号頁・発行日
vol.59, no.1, pp.159-173, 2014 (Released:2014-06-13)
参考文献数
39

This study was conducted to clarify the relationship between race pattern and performance in the men's 400-m race. Using several video cameras, 154 male 400-m sprinters (45-46 s: 26, 47 s: 35, 48 s: 58, 49 s: 35) in official competitions were videotaped at a sampling rate of 59.94 Hz from the start to the finish. The split time at every 50 m from the start was calculated using the Overlay method, which analyzes the split time by superimposing an image of the 400-m race onto an image of the hurdles in a 400-m hurdle race. Each segment was defined as follows: First segment, from the start to the 100-m mark; 2nd segment, from the 100-m mark to the 200-m mark; 3rd segment, from the 200-m mark to the 300-m mark; 4th segment, from the 300-m mark to the finish. The results of regression analysis revealed significant correlations between the 400-m race time and the all of the segment times (r=0.589-0.887, p<0.001), the ratio of the time for the 3rd segment (r=0.290, p<0.001) to that of the 4th segment (r=0.218, p<0.01), the rate of change in running speed from the 1st to the 2nd segments (r=−0.317, p<0.001), and that from the 2nd to the 3rd segments (r=−0.271, p<0.01). However, the relationship between the 400-m race time and the deceleration index (the slope of the linear relationship between running speed and the number of segments from the peak running speed to the finish) was not significant (r=0.154, p=0.056). These results suggest that it is important to maintain running speed in the 2nd and 3rd 100-m segments to achieve high performance in the 400-m sprint.
著者
梶谷 亮輔 前村 公彦 山元 康平 関 慶太郎 尾縣 貢 木越 清信
出版者
一般社団法人 日本体育学会
雑誌
体育学研究 (ISSN:04846710)
巻号頁・発行日
vol.63, no.1, pp.139-149, 2018-06-10 (Released:2018-06-20)
参考文献数
20
被引用文献数
1

The aim of this study was to examine the validity, reliability, and utility of a method for evaluating the characteristics of the counter movement jump. Fifty-two male track and field athletes (sprinters or decathletes) jumped from a 30-cm platform and consciously changed their counter movement times. This study determined the counter movement time required to achieve the highest jump. The results are summarized as follows: 1. The waveform between the counter movement time and jumping height was an inverted U-shape. 2. It is normally accepted that the optimum counter movement time is determined via the jump test. 3. There was a significant correlation between the first test and the re-test in terms of the counter movement time. 4. Participants were classified into 5 groups based on their optimum counter movement times and highest jumping heights. These results suggest that the newly developed jumping test discussed in this study is a valid method for evaluating the characteristics of counter movement.