本研究的目的為瞭解步幅、步頻與平均速度之相關，以參加92年全國中等學校運動會國女組、高女組與國男組、高男組百公尺預賽、複賽及決賽各組前三名選手，共計141人次全程百公尺比賽影片作為研究對象。使用SNOY攝影機（60Hz）全程拍攝選手從起跑開始至越過終點線整個百公尺跑的動作過程。以描述性統計、獨立樣本t考驗和Pearson積差相關進行分析。研究結果如下：一、從預賽至決賽的成績表現，高女組和高男組比國女組和國男組有較快之速度能力，乃由於較大之步幅和較高的步頻。二、本文國男、國女和高男、高女組的步幅和步頻皆為負相關，並達顯著水準（p＜ .05），顯示出步幅和步頻兩者關係十分密切，此乃因所跑距離均為100公尺所導致，跑時要求步頻快，而步幅過大將也直接影響步頻的快慢。三、男選手的步頻與平均速度達顯著水準（p＜ .05），步頻是影響男選手速度表現的重要因素。而女選手的步幅與平均速度達顯著水準（p＜ .05），步幅則是影響女選手速度表現的重要因素。四、高女組在步幅和步頻能力表現上均優於國女組，其中，以步頻能力差距較大，差距1.84％。國男組和高男組的步頻只有些微差距，步幅則由高男組優於國男組，兩組以步幅能力 為主要差距，差距2.95％。

The study based on the clip of the 2003 National-wide high School’s Track and Field Competition considers the target groups of 141 athletes, which were divided into junior high school male group, junior high school female group, senior high school male group and senior high school female group, form third place to first place in preliminary contests, semi-finals, and finals. The4 clip captured the whole movement of sprinters from the starting line to terminal line in 100 meters race by SONY camcorder (60Hz). On the other hand, the purpose of this study focuses on the influence among average speed, step length, and step frequency, and can be used as a supply references for training to coaches as well as athletes. The main statistical data are analysis of the differences between description statistics, t test and Pearson’s multiplication. The result shows: First, from preliminary contests to finals, female and male groups of high school have faster speed because of longer steps and faster step frequency. Second, in the study, the relationship between the male and female groups of junior high school and the male and female groups of senior high school is negative. Due to the same race distance of 100 meter, the value reaches the standard (p<.05). This shows step length is closely related with step frequency, presenting the length of step influences the speed of the step frequency. Third, the average speed and step frequency of male athletes reach the standard value of p<.05, showing the step frequency is the main factor for speed. Nevertheless, the average speed and step length of female athletes reach the standard value of p<.05, showing the step length is the main factor for speed. Forth, in the performance of step length and step frequency, senior high school female group has superiority over junior high school female group while the difference is 1.84% in step frequency ability. The difference in step frequency performance is slight between junior high school male group and senior high school male group. However, the senior high school male group is superior to junior high school male group in step length and the difference is 2.95%.