Training for balance and improved muscle coordination using the Bosu®

Researchers and trainers that promote training on unstable platforms claim that utilizing equipment like the Stability Ball, wobble board and BOSU® Balance Trainer provide a greater stress to the overall musculature. It has been hypothesized that performing exercise in an unstable environment stresses the synergistic and stabilizing muscles around a joint system for any given movement providing a more specific and functional form of training. Studies documenting improved neuromuscular control of balance following such training using floor and BOSU® exercise has yet to be documented. This study examined improvements in balance and neural coordination of muscles involved in balance and standing posture following a five week training program in middle aged females. Sixteen females (mean age = 46.9 ± 8.7 yrs; height 161.1 ± 6.0cm; weight 65.4 ± 11.2 kg) participated in a repeated measures design, with pre and post training measures of balance using the Stork Stand with both eyes open and eyes closed. Muscle recruitment was determined using root mean squared EMG activity in internal oblique, rectus abdominis, errector spinae and biceps femoris muscles. Paired T-tests were used to compare both eyes open and closed conditions, and pre-post for each muscle group. Training included a progression from floor to BOSU® unstable surface, eyes open to eyes closed, static to dynamic exercise, from two to one foot, and progressed to the inclusion off-centred forces (torque). Stork stand balance scores significantly improved for the eyes closed condition (p=0.01) following training. For each muscle group (except the internal oblique pre-training condition (p=0.11)) subjects had a significantly greater muscle activation (p<0.02) during the eyes closed condition as compared to eyes open both pre and post training. Muscle activity was reduced post-training in all muscles in each condition although not all significantly. Rectus abdominis and erector spinae activity was significantly reduced post training in the eyes closed (p<0.02) but not in the eyes open (p>0.05) condition; Biceps femoris activity significantly decreased (p<0.04) in both eyes open and closed conditions. Standing balance improved post training, with favourable changes in stabilizing muscles. Reduced biceps femoris activity suggest that improved coordination of muscles involved in balance reduced body sway; the core muscles were able to control body position with less activity post training suggesting improved muscle coordination and efficiency. These results suggest that progressive BOSU® balance training can improve standing balance in middle aged women, particularly in the more challenging eyes closed condition.