A longitudinal study of sprinting performance and starting reaction time from elementary school to junior high school boys and girls

[出版社版]This longitudinal study investigated the biomechanical analysis of sprinting performance from elementary school to junior high school. The subjects were 45 boys and girls who aged 6 to 15 (the 1st form at elementary school to the 3rd form at junior high school). They were filmed in VTR picture during 50m sprinting, with a pole located every 10m. Using the VTR pictures, starting reaction time; average speed; stride frequency; stride length between the start point and the marked distance point of each were calculated. The results obtained were as follows: 1 Times of 50m sprinting decreased from the 1st form at elementary to the 3rd form at junior high school in boys, and decreased from the 1st form at elementary to the 3rd form at junior high school though there is no change at some forms in girls. 2 In boys, the starting reaction times decreased from the 1st form to the 6th form. They slowed when it was in the 1st form at junior high school, and quickened when it was in the 2nd form and in the 3rd form of junior high school in boys. On the other hand, they quickened when it was in the 3rd form of junior high school though the change was not seen through the whole in girls. 3 The stride frequency was a decreasing tendency from the 1st form at elementary to the 1st form at junior high school, then increased when it was more in the 2nd and 3rd form of junior high school in boys and girls. 4 The stride length increased from the 1st form at elementary to the 3rd form at junior high school in boys. On the other hand, they increased from the 1st to the 6th form, and there is no change from the 6th form to the 3rd form at junior high school in girls. 5 The height ratio stride was high value in the 1st and the 2nd form at junior high school in boys, and was high value in the 5th form at elementary school in girls