Source of improvement in balance control after a training program for ankle proprioception

Previous research on healthy individuals reported improvements in balance control following a purported ankle proprioception-training program. The training may have resulted in a general rather than a specific enhancement of ankle proprioception. To test this hypothesis, subjects were constrained at the hips and trunk with a custom-made thoracolumbosacral orthosis and performed a one-leg standing test with eyes closed and head tilted back, so that they had to rely primarily on their ankle musculature to keep their balance. Subjects were retested after training on the BAPS three times a week for 4 weeks, following the training recommendations of the manual. Subjects' bodies were not constrained during the training. Analysis showed that subjects made improvements during training in performing more difficult tasks on the board. On the one-leg test, however, there were no improvements in sway velocity, number of touchdowns, or falls relative to pretest scores. Improvements observed during training likely resulted from diffuse enhancement of proprioception in other body segments such as the knees, hips, spine, and upper extremities. A training program in control of general balance does not specifically target ankle proprioception.