Effects of eight weeks of bench press and squat power training on stable and unstable surfaces on 1RM and peak power in different testing conditions

BACKGROUND: The use of unstable training environments has been proposed to enhance the specific effects of movement through an increased activation of stabilizers and core muscles, but not for athletic or sport performance training requiring power. OBJECTIVE: The purpose of the study was to determine the effects in muscular strength and power outputs after eight weeks of stable and unstable resistance training in physically active subjects with maximal velocity of movement during concentric phase with the load of 50% of 1RM. METHODS: Seventy two male recreationally active subjects were divided into three groups (Unstable-UTG, Stable-STG and Control-CG). Unstable and Stable training groups trained twice a week for 8 weeks, bench press and squat exercises, 6 sets of 6 repetitions for each exercise. Pre and post-training measures included 1RM and peak power in stable and unstable conditions for bench press and squat. RESULTS: The results showed that there was a significant difference in main effects found with the training induced improvement between the training groups in pre- to post-test in squat 1RM, showing the transfer of specific unstable training exercises on 1RM squat. However, this was not the case in 1RM bench press. Both modalities (Stable and Unstable) produced statistically significant ([Formula: see text] 0.05) training effects on 1RM, with very small increases ranging from 3–7%. Significant main effects for peak power were found for bench press ([Formula: see text] 0.008) and squat ([Formula: see text] 0.025) exercises after the experimental program on both testing surfaces (stable and unstable). Both training programs produced greatest power gains on the surface on which the training was performed. The UTG improved significantly ([Formula: see text] 0.01) on peak power output on both the bench press and squat (12%) on unstable conditions. The STG improved significantly ([Formula: see text] 0.01) on peak power output on both the bench press and squat (7%) during stable conditions. CONCLUSION: The increase of 1RM in previously resistance untrained subjects is lesser than expected. The largest 1RM & peak power increases occurred after squat training on unstable surface, which suggests that unstable surface will not necessarily have negative effects on lower body performance.