Procedure
BBS
Table Tabulation of the experimental protocol for day 1 and day 2.Graphical Abstract of the Experimental Protocol for Day 1 and Day 2 (top and bottom row, respectively).Day 1 consisted of an intake interview and collection of baseline anthropometrics, functional measurements, and cognitive measurements. Functional measures included the 4-Stage Balance test, Falls Efficacy Scale—International (FES-I), Berg Balance Scale (BBS), and Short Physical Performance Battery (SPPB). For 4-Stage Balance test, the following parameters were measured: (1) Feet Side-by-Side, (2) Semi-tandem Stand, (3) Tandem Stand, and (4) One-foot stand.Cognitive measurements included the Montreal Cognitive Assessment (MOCA) and Trail Making Test Parts A and B (TMT-A, TMT-B). In addition, participants were assessed by the Symbol Digit Modalities Test (SDMT) with the following parameters measured: SDMT-60s (SDMT-60), SDMT-90s (SDMT-90), and SDMT time to complete (SDMT-C). Baseline vitals were also obtained, including systolic and diastolic blood pressure and heart rate.Day 2 consisted of training with the mTPAD, a mobile robotic platform that applies timed forces to the pelvisThe mTPAD experimental protocol consisted of 5 trials: Gait Baseline, Test Pre, Training, Test Post, and Gait Post. Participants walked on the Zeno Walkway at their preferred pace throughout all 5 trials. The Zeno Walkway, created by Protokinetics, is a durable pressure-sensitive walkway mat equipped with multiple sensors to analyze gait and balance during walking (This study changed the perturbation forces based on the protocol condition, including lateral, superior/inferior, and diagonal in the frontal plane. These directions were selected to challenge lateral stability during overground gait. A square wave pulse was used for the perturbations for these three force conditions. The square wave had a low value of 0 Newtons, with a high value being the magnitude of the goal force applied during the experiment. The pulse width was 100 ms, and the timing between pulses was random to mitigate learning effects.