Eight weeks of instability resistance training effects on muscular outputs

The objective of this pilot study was to determine the differences in muscular outputs, such as power, force, and velocity, after 8 weeks of instability resistance training. It was hypothesized that instability resistance training would provide significant training gains in muscular outputs. For the purpose of this study, the dynamic bench press and squats were used, since they are some of the most widely performed exercises by athletes. The experimental group consisted of 10 male students, and none of them was a professional athlete, and had not taken part in organized and programmed resistance training in the past year. The participants trained two days per week under unstable conditions for 8 weeks. The unstable conditions were provided by a Swiss ball for the bench press, while barbell squats under unstable conditions were performed on a BOSU ball. Both exercises (the bench press and squat) were performed with a previously established 50% of one-repetition maximum (1RM). An analysis of the obtained results indicated that instability resistance training with 50% of 1RM provides sufficient stimuli to improve muscular outputs, and can significantly increase muscular power in previously untrained young individuals.