The long-term goal of this project is to reduce falls in older adults by improving their ability to recover equilibrium during a slip or trip. The proposed strategy is to use AMES, an FDA-cleared, non-invasive intervention that has been shown to enhance motor performance in able-bodied adults and to reduce sensorimotor impairment in both the upper and lower limbs of people with CNS injuries. Based on results from previous studies, we now hypothesize that the AMES intervention can reduce falls in near-frail older adults (ages 65-95 years) by increasing leg strength, reducing reaction time, and improving leg and axial motor coordination. This project has the following specific aims: (1) to modify the hardware and software of the AMES device to deliver the testing and training proposed in this study, and (2) to test the proof-of-concept, that 9 hours of AMES training on each leg is sufficient to reduce falls in the study participants receiving AMES. In the proposed proof-of-concept study, an AMES device will be used to train both legs of 10 near-frail older residents in the Arkansas Veterans' Home of Fayetteville (Test Group). Another comparable group of 10 participants will also be enrolled, but will not receive AMES training (Control Group). At baseline, all 20 participants will be able to ambulate independently, with or without assistive devices. All participants will be evaluated for sensorimotor impairments (i.e., ankle strength, ankle range of motion and joint position control, and ankle proprioception) and motor function (i.e., balance and gait) at the beginning and end of a 3-month period during which the Test Group will receive AMES training and the Control group will not. During this 3- month period and also in the 3 months that follow (i.e., for a total of 6 months), the incidence of falls in all participants will be tracked. Participants in the Test Group are expected to experience an increase in leg strength, a decrease in leg reaction time, and an improvement in leg proprioception and, in parallel, a reduction in leg impairment and improvement in leg function. Participants in the Test Group are also expected to experience fewer falls over the 6-month tracking period, compared to the number of falls in the Control Group over this same time period.
Our goal is to improve the ability of near-frail older adults to recover equilibrium after losing balance by providing training with AMES, a robotically delivered intervention, with the expectation that this intervention will increase leg strength, decrease reaction time to perturbations, and improve the overall coordination of the lower body.
