Learning Patterns of Pivoting Neuromuscular Control Training-Towards a Learning Model

Learning Patterns of Pivoting Neuromuscular Control Training-Towards a Learning Model 307 172 IEEE Transactions on Biomedical Engineering (TBME)

Learning Patterns of Pivoting Neuromuscular Control Training-Towards a Learning Model

Over the last decades, lower limb therapy using locomotion devices has gained popularity in clinics to improve lower limb functions; however, from these studies, how the learning patterns over the course of a long-term training program change are unknown. Especially, pivoting neuromuscular control is important to reduce injury risks associated with pivoting related injuries and to improve lower limb functions among patients with pivoting related movement disorders. Thereby, the purpose of this study was to investigate the learning patterns in leg pivoting neuromuscular control performance over six-week pivoting neuromuscular control training (POINT) and to estimate how many sessions at beginning are needed to estimate the overall pivoting neuromuscular control learning curve. Twenty subjects participated in 18 sessions of POINT (three sessions per week for six weeks) program using an off-axis elliptical trainer. Performance measures including pivoting instability and stepping speed were quantified for each study session during a stepping task while subjects were asked to control pivoting movements under a slippery condition. Learning curve relating the pivoting instability to training sessions was quantified by the power law and by the exponential curve as a function of sessions or days with three parameters: the limit of learning, rate of learning, and learning capacity. Our results indicated that the power and exponential learning models characterized the learning curves similarly with no differences in R2. No significant sex differences were found in the limit of learning, rate of learning, and learning capacity. Based on R2 and RMSE, data from the first three study sessions might be enough to estimate the pivoting neuromuscular performance over the whole training period. The findings showed that subjects’ motor skills to improve pivoting instability followed the learning curve models. The findings and models can potentially be used to develop more effective and economical subject-specific therapy scheduling and gait therapy protocol.