Can Lowering the Guidance Force of Robot-Assisted Gait Training Induce a Sufficient Metabolic Demand in Subacute Dependent Ambulatory Patients With Stroke?

Abstract Objective To assess the effects of guidance force (GF) and gait speed (GS) on cardiorespiratory responses and energy cost in subacute dependent ambulatory patients with stroke. Design Cross-sectional study. Setting University rehabilitation hospital. Participants Patients with subacute stroke (N=10; mean age, 64.50±19.20y) who were dependent ambulators (functional ambulation category ≤2). Interventions Patients participated in cardiorespiratory tests during robot-assisted gait training. Subjects walked at a fixed percentage (50%) of body weight support and various percentages of GF (100%, 80%, and 60%) and GS (1.4 and 1.8km/h). The therapist encouraged patients to maximize their locomotor ability. Main Outcome Measures During the cardiorespiratory tests, oxygen consumption ( V ˙ o2 ), heart rate, and respiratory exchange ratio were measured continuously to assess cardiometabolic demands. Results There were no significant differences in cardiometabolic demands according to GS (1.4 vs 1.8km/h). There were no significant differences in cardiometabolic demands according to GF at a GS of 1.4km/h. However, lowering GF decreased V ˙ o2 when comparing GFs of 100% (6.89±2.38mL/kg/min), 80% (6.46±1.73mL/kg/min), and 60% (5.77±1.71mL/kg/min) at a GS of 1.8km/h ( P =.03). Conclusions Lowering the GF of robot-assisted gait training at a higher GS cannot induce a sufficient cardiometabolic demand for subacute dependent ambulatory patients with stroke. This implies that it is important to take the patient's functional ability into consideration when choosing training protocols.