Muscle force, explosive strength and vertical jump height are important parameters determining the performance of athletes. Traditionally, high intensity resistance training, explosive strength training and plyometric training are used to improve athletes' performance. Recently, whole body vibration training is recommended for increasing muscle force and explosive strength, because vibrating platform could provide high gravitational acceleration to activate muscle activation and sensory input to spinal reflex. Design: Prospective and randomized control study. Subjects: Healthy male subjects with regular training or competition at least 6 hours per week. Methods: H-reflex, V-wave, triceps surae activation level and rate of force development are measured at pre-training, mid-training (5th week) and post-training. Subjects will receive 8 weeks, 3 times/week, training programs including plyometric jumping or static squat on whole body vibration platform. Data analysis: Data will be analyzed using SPSS 13.0 software (SPSS Inc., Chicago, IL) and two-way ANOVA will be used for data analysis.

Inclusion Criteria:

• subjects who had not been engaged in systematic strength training and had no history of knee, leg, or ankle pain that caused a subject to seek medical help during the year prior to the recruitment.

Exclusion Criteria:

• Subjects who missed more than one training session or participated in any other type of fitness training were excluded.