Instruction of the Rhythm of the Approach Run
in the Long Jump Class and the High Jump Class
2018 Volume 38 Issue 1 Pages 39-51
Details
2018 Volume 38 Issue 1 Pages 39-51
The purpose of this study was to examine the efficiency of the instruction focused on the rhythm of last three steps in the approach run in the long jump class and the high jump class of junior high school. The unit of 7 long jump classes and 8 high jump classes were focused on the rhythm up last three steps in the approach run, and the take-off movement in the first class and the last class were compared kinematically. Subjects in this study were 1st, 2nd and 3rd grade junior high school students, the number of students in the long jump class was 17 and that the high jump class was 22 .<br>
To evaluate the take-off movement quantitatively, two analysis items were used. In long jump, takeoff index which is defined as the value of the vertical velocity at take-off divided by the deceleration of the horizontal velocity during take-off movement, and in high jump, velocity conversion rate which is defined as the value of the vertical velocity at take-off divided by the horizontal velocity at the starting point of take-off movement.<br>
The main results were as follows: (1) In both classes, the record was significantly improved (Long jump:pre 3.19±0.56m, post 3.42±0.57m; p<0.01, High jump: pre 1.09±0.16m, post 1.18±0.14m; p<0.01). (2) In long jump, take-off index was decreased because the deceleration of the horizontal velocity during take-off movement was increased (pre −0.63±0.22m/s, post −0.81±0.20m/s; p<0.01) and the vertical velocity was unchanged (pre 1.87±0.31m/s, post 1.91±0.18m/s; n.s.). (3) In high jump, velocity conversion rate was increased because the horizontal velocity at take-off was decreased (pre 4.88±0.52m/s, post 4.58±0.33m/s; p<0.01) and the vertical velocity was unchanged (pre 2.59±0.46m/s, post 2.56±0.47m/s; p<0.01).<br>
From these result, it suggested that the instruction focused on the rhythm of last three steps in the approach run was effective for high jump, whereas ineffective for long jump.
