異なるジャンプ動作における反応時間と床反力

抄録

The purpose of this study was to examine reaction times and ground reaction force in different vertical jumps. Fifteen healthy adult males were given the following tasks ; “Jump as quickly as possible when a lamp lights, and then touch the target in succession”. The participants jumped vertically ; (1) with a counter movement jump (CMJ), (2) after relaxing and bending both knees as in the technique from old Japanese martial (Hiza-nuki J) (3) hop and jump (HJ) and (4) from a static squatting position (SJ). The parameters were reaction time, maximum vertical ground reaction force and maximum vertical ground reaction force per weight. Results are summarized as follows ; 1. The reaction time in Hiza-nuki J was the shortest except for SJ. 2. The maximum vertical ground reaction force and the maximum vertical ground reaction force per weight in Hiza-nuki J and HJ were larger than CMJ and SJ. 3. There were correlations between HJ and CMJ (r = 0.677, p < 0.05), SJ and HJ (r = 0.701, p < 0.05) in the reaction time. 4. There were correlations between Hiza-nuki J and HJ (r = 0.662, p < 0.05) in the maximum vertical ground reaction force. 5. There were correlations between SJ and CMJ (r = 0.643, p < 0.05) in the maximum vertical ground reaction force per weight. 6. There were negative correlations between the reaction time and the maximum vertical ground reaction force, CMJ (r = -0.736, p < 0.05), Hiza-nuki J (r = -0.615, p < 0.05), SJ (r = -0.543, p < 0.05). There were negative correlations between the reaction time and the maximum vertical ground reaction force per weight, CMJ (r = -0.741, p < 0.05), Hiza-nuki J (r = -0.671, p < 0.05), SJ (r = -0.640, p < 0.05). As the reaction time shortens, the maximum vertical ground reaction force and the maximum vertical ground reaction force per weight tend to increase except for HJ. In conclusion, the results of this study indicate that Hiza-nuki J is a movement that helps jump the quickest, compared with the other movements. In addition, Hiza-nuki J, CMJ, and SJ showed a tendency that the shorter the reaction time, the larger the ground reaction force becomes.