Dynamic Weight Shifting Adaptation Using Exaggerated and Restricted Gait Trajectories with the Morning Walk® End-effector Rehabilitation Robot: A Proof-of-concept Study in Non-impaired Individuals

Research Objectives: To investigate the adaptation of dynamic weight shifting using exaggerated (E) versus restricted (R) leg gait trajectories generated by the Morning Walk® end-effector rehabilitation robot in non-impaired individuals, and to identify its immediate effect on weight shifting during overground walking.

Design: A proof-of-concept study employing a repeated measures design to compare the adaptation of E and R gait trajectories on dynamic weight shifting using the Morning Walk® (CUREXO Inc., South Korea), and to assess the immediate effect of weight shifting on overground walking.

Setting: A controlled laboratory environment equipped with an end-effector robot capable of generating independent dominant and non-dominant leg gait trajectories.

Participants: Fourteen non-impaired individuals (8 females, 6 males; mean age 24.9 ± 3.6 years).

Interventions: Participants performed 15 minutes of asymmetrical walking using the Morning Walk® end-effector lower limb robot, which restricted the dominant leg and guided the exaggerated gait trajectories of the non-dominant leg.

Main Outcome Measures: The primary outcome measure was the peak vertical ground reaction forces (vGRF), assessed using the Tekscan In-shoe system during walking with the Morning Walk. Weight-shifting adaptation was measured over 10 steps at initial (2 mins), middle (8 mins), and late (14 mins) intervals. The vGRF was normalized to body weight (lb). Secondary measures included weight shift differences between the E and R legs, compared pre- and post-Morning Walk sessions during overground walking.

Results: For the Morning Walk session, a one-way repeated measures ANOVA identified a significant reduction in weight shifting on the E leg (F(2, 26) = 9.22, p < 0.001), with no significant change on the R leg (F(2, 26) = 2.70, p = 0.086). Bonferroni tests indicated that vGRF during the final measurements was significantly lower than the initial measurements (p = 0.029), but not significantly different from the middle measurements (p = 0.303). A paired t-test showed that weight shifting occurred significantly more on the R leg than the E leg after the Morning Walk session (t(13) = 2.21, p = 0.046).

Conclusions: The study demonstrates that dynamic weight adaptation on the E leg became significant by the final measurement during the Morning Walk session. There was immediate greater weight shifting on the R leg during overground walking after a 15-minute Morning Walk session.

Author(s) Disclosures: I have received a sponsorship grant from CUREXO Inc. for my research, and the sponsor company provides the Morning Walk® end-effector rehabilitation robot used in this study.