Author(s): FURUHASHI, Y., MURATOMI, K., YOSHIDA, T., TANIGAWA, S., MAEMURA, H., Institution: UNIVERSITY OF TSUKUBA, Country: JAPAN, Abstract-ID: 493

INTRODUCTION:
Attentional focus strategy (AFS) can promote a neutral (NEUT), internal (INT), or external focus of attention (EXT) and improves various sports performance. Drop jump (DJ) is a plyometric training that enhances the stretch-shortening cycle in lower limb muscles and is commonly used by S&C coaches and athletes. Furuhashi et al. 1) showed that DJ performance can be improved by NEUT for DJ experienced athletes and EXT for DJ inexperienced athletes. Thus, it is clear that AFS can be effective coaching method in DJ. However, all these studies are limited to examining the immediate effects of AFS on DJ, and the effects of AFS on motor learning of DJ have not yet been clarified. These findings provide the necessary knowledge for DJ inexperienced athletes to use DJ as training.
METHODS:
24 DJ inexperienced female college student were randomly divided into 3 groups (NEUT, INT, and EXT). They performed 6 sets of 5 DJ trainings (total 30 trials) using each focus of attention. Pre-test and post-test were performed before and after training, followed 3 days later by Retention-test 1 and 7 days later by Retention-test 2 to perform 2 trials DJ without instruction. The instructions for each condition were as follows: NEUT: "Perform the jump to the best of your ability", INT: "Step off the box, land on the balls of your feet, then fully and explosively extend your ankles, knees, and hips to jump as high as possible", EXT: "Step off the box, jump fast, imagine the ground is hot, get off the ground quickly, imagine you are a stiff spring, and focus on jumping to the roof." Three-dimensional coordinates of the 12 retroreflective markers fixed on each subject’s body were obtained using a Vicon T20 system (Vicon Motion Systems Ltd.) with 10 cameras operating at 250 Hz. Ground reaction force was measured by a force platform at a rate of 1000 Hz. From the measured data, reactive strength index (RSI), contact time (CT), jump height (JH), joint torque, joint power, angular of the lower leg joints were calculated.
RESULTS:
In all groups, DJ performance improved from Set 1 to Set 6 during the training session. All groups also improved DJ performance from Pre-test to Post-test. On the Retention-test, the EXT group showed higher DJ performance than the other groups. In addition, EXT group performed rational force exertion and movement to improve DJ performance.
CONCLUSION:
These results showed that AFS is effective for DJ motor learning. In particular, it has been shown that EXT can be used by DJ inexperienced athletes to effectively learn reasonable force exertion and movement to improve DJ performance. S&C coaches may benefit from using plyometrics instruction with AFS to improve the performance of athletes at a wide range of levels.

REFFERENCES:
1) Furuhashi Y, Hioki Y, Yoshimoto S, and Hayashi R. Effect of Neutral, Internal, and External Focus on Drop Jump Performance: Is Drop Jump Performance Affected by Plyometric Training Experience? J. Strength Cond. Res. 36: 3319-3323, 2022.